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Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common forms of muscular dystrophy, affecting individuals across the lifespan with variable severity. Advances in genetic understanding and therapeutic development have led to an era of promising disease-modifying strategies. In this episode, Katie Grouse, MD FAAN, speaks with Renatta N. Knox, MD, PhD, author of the article “Facioscapulohumeral Muscular Dystrophy” in the Continuum® October 2025 Muscle and Neuromuscular Junction Disorders issue. Dr. Grouse is a Continuum® Audio interviewer and a clinical assistant professor at the University of California San Francisco in San Francisco, California. Dr. Knox is an assistant professor of neurology in the Division of Pediatric Neurology and Neuromuscular Section at Washington University School of Medicine in St. Louis, Missouri. Additional Resources Read the article: Facioscapulohumeral Muscular Dystrophy Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN  Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Grouse: This is Dr Katie Grouse. Today I'm interviewing Dr Renatta Knox about her article on fascioscapulohumeral muscular dystrophy, which appears in the October 2025 Continuum issue on muscle and neuromuscular junction disorders. Welcome to the podcast, and please introduce yourself to our audience. Dr Knox: Hi Katie, thank you so much for the invitation for the audio interview. I'm looking forward to our conversation. As she mentioned, my name is Renata Knox. It's a pleasure to be here today. Dr Grouse: I'd like to start by asking, what is the key message that you hope your readers will take from your article? Dr Knox: I would say two things. The first is an appreciation and understanding of the unique genetic mechanism that leads to FSHD. And the second is the really exciting therapy landscape that we find ourselves in. So, we're hopeful that there will actually be disease-modifying therapies for FSHD soon. Dr Grouse: We're really looking forward to learning more about that. Now, before we get to that piece, could you just remind us of the clinical manifestations and features that are specific to FSHD? Dr Knox: So, one of the most unique things about FSHD that we see clinically is the pattern of weakness. So, one of the first features is that it's asymmetric. And then there are certain muscle groups that typically are affected, and that's partly where the name comes from. So, we see effects in the face, the limbs, the trunk; and so, those are some of the unique features that we see clinically. Dr Grouse: I'd love it if you could walk us through how you approach diagnosing a patient who presents with proximal weakness where FSHD is in your differential. Dr Knox: Yeah, it's a really great question. So, I would say it depends. So, I actually focus on FSHD in my clinical practice. So, many times patients are referred to me because there's a very high suspicion or there's a known family history of FSHD. So, that's one category of cases. I would say the other category of case is where it's, as you said, maybe more proximal weakness more broadly. Someone that’s before me who has a known family history, they really have some of the characteristic physical features---which I'm pretty attuned to, as this is, you know, part of my subspecialty---I'll actually go directly to FSHD genetic testing. And that is one of the unique features of this disease, that the next-generation sequencing panels that are typically used for some of our other muscle diseases, FSHD is not captured on those. So, we actually have to send targeted testing for FSHD to diagnose it. So, that is one category where, again, I have a very high suspicion either based on their clinical presentation and/or a known family history, then I will actually go directly to FSHD-targeted genetic testing. In the second case, where it is one of the conditions that I'm considering among others, I will do more broad testing. So, I will get a CK level to see if there's evidence of muscle breakdown. I'll likely also do one of the next-generation sequencing panels that we have access to, which will allow us to identify, potentially, one to two hundred potential muscle diseases. And then again, if FSHD is higher on my differential in that second group of patients, then I will also send targeted FSHD-specific testing. Dr Grouse: That's really helpful. And I'm wondering if you have any thoughts about common pitfalls that you've seen when providers are trying to work this up? Dr Knox: I don't know if I would say pitfalls. I think I would acknowledge that it's challenging. My subspecialty training in neuromuscular medicine and also gene therapy. And so FSHD is pretty high on my radar. But I would say in neurology in general---and then, you know, the general medical population---,it really isn't something that many people are seeing. So, I would say what patients will communicate to us sometimes is some frustration that maybe it took time to make the diagnosis, but I just have a deep understanding that it's not something that is on many people's radars. And I think, again, it's tricky because it's not picked up on these next-generation sequencing panels, which many of us can send pretty easily. It will be missed. And I will say the biggest pitfall is, again, if you're not thinking about it and you don't send that testing, you actually- it's very difficult to diagnose it. Dr Grouse: Thank you so much for highlighting that. I think there are many people who are not aware that those different panels really aren't picking that up and that they have to test specifically. So, I think that's a great thing for all of us to keep in mind. Are there any tips or tricks to the diagnosis, other than the genetic issues that you mentioned, that sometimes can really bring this diagnosis to the forefront? Dr Knox: I think things that really tip me off to having a higher suspicion for FSHD is facial weakness that we can detect on our exam. Scapular winging---again, there's a small subset of disorders which can impact that. Someone who's presenting with foot drop, you know, with facial weakness, I think definitely about FSHD more. Also, clinically, kind of the presentation or things that they're beginning to have difficulty with is a tip-off. So, if someone is an athlete, like, they're a volleyball player or basketball player and they say, oh, I'm having difficulties, you know, with movements that require them to elevate their arm, which can be a sign of the shoulder weakness that we classically see. Or someone who says, oh, I'm having a harder time shampooing my hair or combing my hair. So those can be tip-offs again, which are basically referencing the type of weakness that they have. Another feature of FSHD which isn't necessarily as broadly appreciated is that pain and fatigue are very common. So, if someone is coming in and saying, actually, I also have a significant amount of fatigue as well or a lot of pain, that's something that can tip me off to it. Hearing loss is something that we can also see in up to 20% of patients with FSHD. So, if they are having those symptoms or saying they're ringing in their ears, these are some things that will make me begin to think about it more. Dr Grouse: Oh, really helpful. I also found it really fascinating reading some of the very FSHD-specific clinical signs, some interesting- some diagrams and pictures as well, that are very specific to the pattern of weakness that develops in FSHD. So, I encourage our listeners to check that out. But are there any highlights from those little clinical pearls that you'd like to point out? Dr Knox: I think the poly-hill sign---so, these are these literal hills that we can see in the shoulders of patients with FSHD---is pretty classic. Popeye arms, which is this older term that we still use that has to do with which muscle groups are preserved versus those that have atrophy. So that's a common feature. And then I would say, really, the asymmetry is something that is a unique feature in FSHD. And again, we did our best to provide good representative images. So again, as you mentioned, Katie, I would really encourage people to look at those images and then think about cases that they may have seen and how similar they are so they can begin to recognize those signs as well. Dr Grouse: Now going back to the genetic topic, the complex genetic underpinnings of FSHD are really well-explained in your article; and again, worth taking a look at to remind ourselves of everything that's of that pathology. Now, I was wondering though, if you could give us a brief overview of how we should approach genetic testing in a suspected case of FSHD? You mentioned some specific panels, but it does sound like there's some more complexity to it as well. Dr Knox: Yes, and I'll just kind of briefly explain that complexity. Part of the thing that we're detecting in the genetic testing is the repeat number. And so, we're actually looking for a contraction in a repeat number. So, not an expansion, which were typical for some of the diseases that we think about, the trinucleotide repeat disorders. And this is why it’s not captured in the next-generation sequencing panels, because they do not currently have the ability to do that. And so, again, what the type of testing that I do really depends on my suspicion. So again, if my suspicion is very

While genetic testing has replaced muscle biopsy in the diagnosis of many genetic myopathies, clinical assessment and the integration of clinical and laboratory findings remain key elements for the diagnosis and treatment of muscle diseases. In this episode, Casey Albin, MD, speaks with Margherita Milone, MD, PhD, FAAN, FANA, author of the article “A Pattern Recognition Approach to Myopathy” in the Continuum® October 2025 Muscle and Neuromuscular Junction Disorders issue. Dr. Albin is a Continuum® Audio interviewer, associate editor of media engagement, and an assistant professor of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia. Dr. Milone is a professor of neurology and the director of the Muscle Pathology Laboratory at Mayo Clinic College of Medicine and Science in Rochester, Minnesota. Additional Resources Read the article: A Pattern Recognition Approach to Myopathy Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @caseyalbin Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Albin: Hello, this is Dr Casey Albin. Today I'm interviewing Dr Margherita Milone on her article on a pattern recognition approach to myopathy, which appears in the October 2025 Continuum issue on muscle and neuromuscular junction disorders. Welcome to the podcast, Dr Milone. Thank you so much for joining us. I'll start off by having you introduce yourself to our listeners. Dr Milone: Hello Casey, thank you so much for this interview and for bringing the attention to the article on muscle diseases. So, I'm Margherita Milone. I'm one of the neuromuscular neurologists at Mayo Clinic in Rochester. I have been interested in muscle disorders since I was a neurology resident many years ago. Muscle diseases are the focus of my clinical practice and research interest. Dr Albin: Wonderful. Thank you so much. When I think about myopathies, I generally tend to think of three large buckets: the genetic myopathy, the inflammatory myopathies, and then the necrotizing myopathies. Is that a reasonable approach to conceptualizing these myopathies? Dr Milone: Yeah, the ideology of the myopathies can be quite broad. And yes, we have a large group of genetic muscle diseases, which are the most common. And then we have immune-mediated muscle diseases, which include inflammatory myopathies as well as some form of necrotizing myopathies. Then we have some metabolic myopathies, which could be acquired or could be genetic. And then there are muscle diseases that are due to toxins as well as to infection. Dr Albin: Wow. So, lots of different etiologies. And that really struck me about your article, is that these can present in really heterogeneous ways, and some of them don't really read the rule book. So, we have to have a really high level of suspicion, for someone who's coming in with weakness, to remember to think about a myopathy. One of the things that I like to do is try to take us through a little bit of a case to sort of walk us through how you would approach if someone comes in. So, let's say you get, you know, a forty-year-old woman, and she's presenting with several months of progressive weakness. And she says that even recently she's noted just a little bit of difficulty swallowing. It feels to her like things are getting stuck. What are some of the things when you are approaching the history that would help you tease this to a myopathy instead of so many other things that can cause a patient to be weak? Dr Milone: Yes. So, as you mentioned, people who have a muscle disease have the muscle weakness often, but the muscle weakness is not just specific for a muscle disease. Because you can have a mass weakness in somebody who has a neurogenic paralysis. The problem with diagnosis of muscle diseases is that patients with these disorders have a limited number of symptom and sign that does not match the large heterogeneity of the etiology. So, in someone who has weakness, that weakness could represent a muscle disease, could represent an anterior horn cell disease, could represent a defect of neuromuscular junction. The clinical history of weakness is not sufficient by itself to make you think about a muscle disease. You have to keep that in the differential diagnosis. But your examination will help in corroborating your suspicion of a muscle disease. Let's say if you have a patient, the patient that you described, with six months’ history of progressive weakness, dysphagia, and that patient has normal reflexes, and the patient has no clinical evidence for muscle fatigability and no sensory loss, then the probability that that patient has a myopathy increases. Dr Albin: Ah, that's really helpful. I'm hearing a lot of it is actually the lack of other findings. In some ways it's asking, you know, have you experienced numbness and tingling? And if not, that’s sort of eliminating that this might not be a neuropathy problem. And then again, that fatigability- obviously fatigability is not specific to a neuromuscular junction, but knowing that is a hallmark of myasthenia, the most common of neuromuscular disorders. Getting that off the table helps you say, okay, well, it's not a neuromuscular junction problem, perhaps. Now we have to think more about, is this a muscle problem itself? Are there any patterns that the patients describe? I have difficulty getting up from a chair, or I have difficulty brushing my hair. When I think of myopathies, I historically have thought of, sort of, more proximal weakness. Is that always true, or not so much? Dr Milone: Yeah. So, there are muscle diseases that involve predominantly proximal weakness. For example, the patient you mentioned earlier could have, for example, an autoimmune muscle disease, a necrotizing autoimmune myopathy; could have, perhaps, dermatomyositis if there are skin changes. But a patient with muscle disease can also present with a different pattern of weakness. So, myopathies can lead to this weakness, and foot drop myopathies can cause- can manifest with the weakness of the calf muscles. So, you may have a patient presenting to the clinic who has no the inability to stand on tiptoes, or you may have a patient who has just facial weakness, who has noted the difficulty sealing their lips on the glasses when they drink and experiencing some drooling in that setting, plus some hand weakness. So, the muscle involved in muscle diseases can vary depending on the underlying cause of the muscle disease. Dr Albin: That's really helpful. So, it really is really keeping an open mind and looking for some supporting features, whether it's bulbar involvement, extraocular eye muscle involvement; looking, you know, is it proximal, is it distal? And then remembering that any of those patterns can also be a muscle problem, even if sometimes we think of distal being more neuropathy and proximal myopathy. Really, there's a host of ranges for this. I really took that away from your article. This is, unfortunately, not just a neat way to box these. We really have to have that broad differential. Let me ask another question about your history. How often do you find that patients complain of, sort of, muscular cramping or muscle pain? And does that help you in terms of deciding what type of myopathy they may have? Dr Milone: Many patients with muscle disease have muscle pain. The muscle pain could signal a presence of inflammation in skeletal muscle, could be the result of overuse from a muscle that is not functioning normally. People who have myotonia experience muscle stiffness and muscle pain. Patients who have a metabolic myopathy usually have exercise-induced muscle pain. But, as we know, muscle pain is also very nonspecific, so we have to try to find out from the patient in what setting the pain specifically occurs. Dr Albin: That's really helpful. So, it's asking a little bit more details about the type of cramping that they have, the type of pain they may be experiencing, to help you refine that differential. Similarly, one of the things that I historically have always associated with myopathies is an elevation in the CK, or the creatinine kinase. How sensitive and specific is that, and how do you as the expert sort of take into account, you know, what their CK may be? Dr Milone: So, this is a very good point. And the elevation of creatine kinase can provide a clue that the patient has a muscle disease, but it is nonspecific for muscle disease because we know that elevation of creatine kinase can occur in the setting of a neurogenic process. For example, we can see elevation of the creatine kinase in patients who have ALS or in patients who have spinal muscular atrophy. And in these patients---for example, those with spinal muscular atrophy---the CK elevation can be also of significantly elevated up to a couple of thousand. Conversely, we can have muscle diseases where the CK elevation does not occur. Examples of these are some genetic muscle disease, but also some acquired muscle diseases. If we think of, for example, cases where inflammation in the muscle occurs in between muscle fibers, more in the interstitium of the muscle, that disease may not lead to significant elevation of the CK. Dr Albin: That's super helpful. So, I'm hearing you say CK may be helpful, but it's neither completely sensitive nor completely specific when we're thinking about myopathic disorders. Dr Milone:

Functional movement disorders are a common clinical concern for neurologists. The principle of “rule-in” diagnosis, which involves demonstrating the difference between voluntary and automatic movement, can be carried through to explanation, triage, and evidence-based multidisciplinary rehabilitation therapy. In this episode, Gordon Smith, MD, FAAN speaks Jon Stone, PhD, MB, ChB, FRCP, an author of the article “Multidisciplinary Treatment for Functional Movement Disorder” in the Continuum® August 2025 Movement Disorders issue. Dr. Smith is a Continuum® Audio interviewer and a professor and chair of neurology at Kenneth and Dianne Wright Distinguished Chair in Clinical and Translational Research at Virginia Commonwealth University in Richmond, Virginia. Dr. Stone is a consultant neurologist and honorary professor of neurology at the Centre for Clinical Brain Sciences at the University of Edinburgh in Edinburgh, United Kingdom. Additional Resources Read the article: Multidisciplinary Treatment for Functional Movement Disorder Subscribe to Continuum®: shop.lww.com/Continuum Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @gordonsmithMD Guest: @jonstoneneuro Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. This exclusive Continuum Audio interview is available only to you, our subscribers. We hope you enjoy it. Thank you for listening. Dr Smith: Hello, this is Dr Gordon Smith. Today I've got the great pleasure of interviewing Dr Johnstone about his article on the multidisciplinary treatment for functional neurologic disorder, which he wrote with Dr Alan Carson. This article will appear in the August 2025 Continuum issue on movement disorders. I will say, Jon, that as a Continuum Audio interviewer, I usually take the interviews that come my way, and I'm happy about it. I learn something every time. They're all a lot of fun. But there have been two instances where I go out and actively seek to interview someone, and you are one of them. So, I'm super excited that they allowed me to talk with you today. For those of our listeners who understand or are familiar with FND, Dr Stone is a true luminary and a leader in this, both in clinical care and research. He's also a true humanist. And I have a bit of a bias here, but he was the first awardee of the Ted Burns Humanism in Neurology award, which is a real honor and reflective of your great work. So welcome to the podcast, Jon. Maybe you can introduce yourself to our audience. Dr Stone: Well, thank you so much, Gordon. It was such a pleasure to get that award, the Ted Burns Award, because Ted was such a great character. I think the spirit of his podcasts is seen in the spirit of these podcasts as well. So, I'm a neurologist in Edinburgh in Scotland. I'm from England originally. I'm very much a general neurologist still. I still work full-time. I do general neurology, acute neurology, and I do two FND clinics a week. I have a research group with Alan Carson, who you mentioned; a very clinical research group, and we've been doing that for about 25 years. Dr Smith: I really want to hear more about your clinical approach and how you run the clinic, but I wonder if it would be helpful for you to maybe provide a definition. What's the definition of a functional movement disorder? I mean, I think all of us see these patients, but it's actually nice to have a definition. Dr Stone: You know, that's one of the hardest things to do in any paper on FND. And I'm involved with the FND society, and we're trying to get together a definition. It's very hard to get an overarching definition. But from a movement disorder point of view, I think you're looking at a disorder where there is an impairment of voluntary movement, where you can demonstrate that there is an automatic movement, which is normal in the same movement. I mean, that's a very clumsy way of saying it. Ultimately, it's a disorder that's defined by the clinical features it has; a bit like saying, what is migraine? You know? Or, what is MS? You know, it's very hard to actually say that in a sentence. I think these are disorders of brain function at a very broad level, and particularly with FND disorders, of a sort of higher control of voluntary movement, I would say. Dr Smith: There's so many pearls in this article and others that you've written. One that I really like is that this isn't a diagnosis of exclusion, that this is an affirmative diagnosis that have clear diagnostic signs. And I wonder if you can talk a little bit about the diagnostic process, arriving at an FND diagnosis for a patient. Dr Stone: I think this is probably the most important sort of “switch-around” in the last fifteen, twenty years since I've been involved. It's not new information. You know, all of these diagnostic signs were well known in the 19th century; and in fact, many of them were described then as well. But they were kind of lost knowledge, so that by the time we got to the late nineties, this area---which was called conversion disorder then---it was written down. This is a diagnosis of exclusion that you make when you've ruled everything out. But in fact, we have lots of rule in signs, which I hope most listeners are familiar with. So, if you've got someone with a functional tremor, you would do a tremor entrainment test where you do rhythmic movements of your thumb and forefinger, ask the patient to copy them. It's very important that they copy you rather than make their own movements. And see if their tremor stops briefly, or perhaps entrains to the same rhythm that you're making, or perhaps they just can't make the movement. That might be one example. There's many examples for limb weakness and dystonia. There's a whole lot of stuff to learn there, basically, clinical skills. Dr Smith: You make a really interesting point early on in your article about the importance of the neurological assessment as part of the treatment of the patient. I wonder if you could talk to our listeners about that. Dr Stone: So, I think, you know, there's a perception that- certainly, there was a perception that that the neurologist is there to make a diagnosis. When I was training, the neurologist was there to tell the patient that they didn't have the kind of neurological problem and to go somewhere else. But in fact, that treatment process, when it goes well, I think begins from the moment you greet the patient in the waiting room, shake their hand, look at them. Things like asking the patient about all their symptoms, being the first doctor who's ever been interested in their, you know, horrendous exhaustion or their dizziness. You know, questions that many patients are aware that doctors often aren't very interested in. These are therapeutic opportunities, you know, as well as just taking the history that enable the patient to feel relaxed. They start thinking, oh, this person's actually interested in me. They're more likely to listen to what you've got to say if they get that feeling off you. So, I'd spend a lot of time going through physical symptoms. I go through time asking the patient what they do, and the patients will often tell you what they don't do. They say, I used to do this, I used to go running. Okay, you need to know that, but what do they actually do? Because that's such valuable information for their treatment plan. You know, they list a whole lot of TV shows that they really enjoy, they're probably not depressed. So that's kind of useful information. I also spend a lot of time talking to them about what they think is wrong. Be careful, that they can annoy patients, you know. Well, I've come to you because you're going to tell me what's wrong. But what sort of ideas had you had about what was wrong? I need to know so that I can deal with those ideas that you've had. Is there a particular reason that you're in my clinic today? Were you sent here? Was it your idea? Are there particular treatments that you think would really help you? These all set the scene for what's going to come later in terms of your explanation. And, more importantly, your triaging of the patient. Is this somebody where it's the right time to be embarking on treatment, which is a question we don't always ask yourself, I think. Dr Smith: That's a really great point and kind of segues to my next question, which is- you talked a little bit about this, right? Generally speaking, we have come up with this is a likely diagnosis earlier, midway through the encounter. And you talked a little bit about how to frame the encounter, knowing what's coming up. And then what's coming up is sharing with the patient our opinion. In your article, you point out this should be no different than telling someone they have Parkinson's disease, for instance. What pearls do you have and what pitfalls do you have in how to give the diagnosis? And, you know, a lot of us really weren't trained to do this. What's the right way, and what are the most common land mines that folks step on when they're trying to share this information with patients? Dr Stone: I've been thinking about this for a long time, and I've come to the conclusion that all we need to do with this disorder is stop being weird. What goes wrong? The main pitfall is that people think, oh God, this is FND, this is something a bit weird. It's in a different box to all of the other things and I have to do something weird. And people end up blurting out things like, well, your scan was normal or, you haven't got epilepsy or, you haven't got Parkinson's disease. That's not what you normally do. It's weird. What you normally do is you take a deep breath and you say, I'm sorry to tell you've got Parkinson's disease or, you have this type of dystonia. That's what you normal

Paroxysmal movement disorders refer to a group of highly heterogeneous disorders that present with attacks of involuntary movements without loss of consciousness. These disorders demonstrate considerable and ever-expanding genetic and clinical heterogeneity, so an accurate clinical diagnosis has key therapeutic implications. In this episode, Kait Nevel, MD, speaks with Abhimanyu Mahajan, MD, MHS, FAAN, author of the article “Paroxysmal Movement Disorders” in the Continuum® August 2025 Movement Disorders issue. Dr. Nevel is a Continuum® Audio interviewer and a neurologist and neuro-oncologist at Indiana University School of Medicine in Indianapolis, Indiana. Dr. Mahajan is an assistant professor of neurology and rehabilitation medicine at the James J. and Joan A. Gardner Family Center for Parkinson’s Disease and Movement Disorders at the University of Cincinnati in Cincinnati, Ohio. Additional Resources Read the article: Paroxysmal Movement Disorders Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @IUneurodocmom Guest: @MahajanMD Full episode transcript available here Dr Jones: This is Doctor Lyell Jones, editor in chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Nevel: Hello, this is Dr Kait Nevel. Today I'm interviewing doctor Abhi Mahajan about his article on diagnosis and management of paroxysmal movement disorders, which appears in the August 2025 Continuum issue on movement disorders. Abhi, welcome to the podcast and please introduce yourself to the audience. Dr Mahajan: Thank you, Kait. Thank you for inviting me. My name is Abhi Mahajan. I'm an assistant professor of neurology and rehabilitation medicine at the University of Cincinnati in Cincinnati, Ohio. I'm happy to be here. Dr Nevel: Wonderful. Well, I'm really excited to talk to you about your article today on this very interesting and unique set of movement disorders. So, before we get into your article a little bit more, I think just kind of the set the stage for the discussion so that we're all on the same page. Could you start us off with some definitions? What are paroxysmal movement disorders? And generally, how do we start to kind of categorize these in our minds? Dr Mahajan: So, the term paroxysmal movement disorders refers to a group of highly heterogeneous disorders. These may present with attacks of involuntary movements, commonly a combination of dystonia and chorea, or ataxia, or both. These movements are typically without loss of consciousness and may follow, may follow, so with or without known triggers. In terms of the classification, these have been classified in a number of ways. Classically, these have been classified based on the trigger. So, if the paroxysmal movement disorder follows activity, these are called kinesigenic, paroxysmal, kinesigenic dyskinesia. If they are not followed by activity, they're called non kinesigenic dyskinesia and then if they've followed prolonged activity or exercise they're called paroxysmal exercise induced dyskinesia. There's a separate but related group of protogynous movement disorders called episodic attacks here that can have their own triggers. Initially this was the classification that was said. Subsequent classifications have placed their focus on the ideology of these attacks that could be familiar or acquired and of course understanding of familiar or genetic causes of paroxysmal movement disorders keeps on expanding and so on and so forth. And more recently, response to pharmacotherapy and specific clinical features have also been introduced into the classification. Dr Nevel: Great, thank you for that. Can you share with us what you think is the most important takeaway from your article for the practicing neurologist? Dr Mahajan: Absolutely. I think it's important to recognize that everything that looks and sounds bizarre should not be dismissed as malingering. Such hyperkinetic and again in quotations, “bizarre movements”. They may appear functional to the untrained eye or the lazy eye. These movements can be diagnosed. Paroxysmal movement disorders can be diagnosed with a good clinical history and exam and may be treated with a lot of success with medications that are readily available and cheap. So, you can actually make a huge amount of difference to your patients’ lives by practicing old-school neurology. Dr Nevel: That's great, thank you so much for that. I can imagine that scenario does come up where somebody is thought to have a functional neurological disorder but really has a proximal movement disorder. You mentioned that in your article, how it's important to distinguish between these two, how there can be similarities at times. Do you mind giving us a little bit more in terms of how do we differentiate between functional neurologic disorder and paroxysmal movement disorder? Dr Mahajan: So clinical differentiation of functional neurological disorder from paroxysmal movement disorders, of course it's really important as a management is completely different, but it can be quite challenging. There's certainly an overlap. So, there can be an overlap with presentation, with phenomenology. Paroxysmal nature is common to both of them. In addition, FND and PMD's may commonly share triggers, whether they are movement, physical exercise. Other triggers include emotional stimuli, even touch or auditory stimuli. What makes it even more challenging is that FND’s may coexist with other neurological disorders, including paroxysmal movement disorders. However, there are certain specific phenom phenotypic differences that have been reported. So specific presentations, for example the paroxysms may look different. Each paroxysm may look different in functional neurological disorders, specific phenotypes like paroxysmal akinesia. So, these are long duration episodes with eyes closed. Certain kinds of paroxysmal hyperkinesia with ataxia and dystonia have been reported. Of course. More commonly we see PNES of paroxysmal nonepileptic spells or seizures that may be considered paroxysmal movement disorders but represent completely different etiology which is FND. Within the world of movement disorders, functional jerks may resemble propiospinal myoclonus which is a completely different entity. Overall, there are certain things that help separate functional movement disorders from paroxysmal movement disorders, such as an acute onset variable and inconsistent phenomenology. They can be suggestibility, distractibility, entrainment, the use of an EMG may show a B-potential (Bereitschaftspotential) preceding the movement in patients with FND. So, all of these cues are really helpful. Dr Nevel: Great, thanks. When you're seeing a patient who's reporting to these paroxysmal uncontrollable movements, what kind of features of their story really tips you off that this might be a proximal movement disorder? Dr Mahajan: Often these patients have been diagnosed with functional neurological disorders and they come to us. But for me, whenever the patient and or the family talk about episodic movements, I think about these. Honestly, we must be aware that there is a possibility that the movements that the patients are reporting that you may not see in clinic. Maybe there are obvious movement disorders. Specifically, there's certain clues that you should always ask for in the history, for example, ask for the age of onset, a description of movements. Patients typically have videos or families have videos. You may not be able to see them in clinic. The regularity of frequency of these movements, how long the attacks are, is there any family history of or not? On the basis of triggers, whether, as I mentioned before, do these follow exercise? Prolonged exercise? Or neither of the above? What is the presentation in between attacks, which I think is a very important clinical clue. Your examination may be limited to videos, but it's important not just to examine the video which represents the patient during an attack, but in between attacks. That is important. And of course, I suspect we'll get to the treatment, but the treatment can follow just this part, the history and physical exam. It may be refined with further testing, including genetic testing. Dr Nevel: Great. On the note of genetic testing, when you do suspect a diagnosis of paroxysmal movement disorder, what are some key points for the provider to be aware of about genetic testing? How do we go about that? I know that there are lots of different options for genetic testing and it gets complicated. What do you suggest? Dr Mahajan: Traditionally, things were a little bit easier, right, because we had a couple of genes that have been associated with the robust movement disorders. So, genetic testing included single gene testing, testing for PRRT2 followed by SLC2A. And if these were negative, you said, well, this is not a genetic ideology for paroxysmal movement disorders. Of course, with time that has changed. There's an increase in known genes and variants. There is increased genetic entropy. So, the same genetic mutation may present with many phenotypes and different genetic mutations may present with the similar phenotype. Single gene testing is not a high yield approach. Overall genetic investigations for paroxysmal movement disorders use next generation sequencing or whole exome sequence panels which allow for sequencing of multiple genes simultaneously. The reported diagnostic yield with let's say next generation sequencing is around 3

Tics are movements or sounds that are quick, recurrent, and nonrhythmic. They fluctuate over time and can be involuntary or semivoluntary. Although behavioral therapy remains the first-line treatment, modifications to comprehensive behavioral intervention have been developed to make treatment more accessible. In this episode, Casey Albin, MD, speaks with Jessica Frey, MD, author of the article “Tourette Syndrome and Tic Disorders” in the Continuum® August 2025 Movement Disorders issue. Dr. Albin is a Continuum® Audio interviewer, associate editor of media engagement, and an assistant professor of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia. Dr. Frey is an assistant professor of neurology, Movement Disorders Fellowship Program Director, and Neurology Student Clerkship Director at the Rockefeller Neuroscience Institute in the department of neurology at West Virginia University in Morgantown, West Virginia. Additional Resources Read the article: Tourette Syndrome and Tic Disorders Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @caseyalbin Transcript Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Albin: Hi all, this is Dr Casey Albin. Today I'm interviewing Dr Jessica Frey about her article Tourette Syndrome and Tic Disorders, which appears in the August 2025 Continuum issue on movement disorders. Dr Frey, thank you so much for being here, and welcome to the podcast. I'd love for you to briefly introduce yourself to our audience. Dr Frey: Thank you for having me here today. My name is Jessica Frey, and I am a movement disorder specialist at West Virginia University. I'm also the movement disorder fellowship director, as well as the neurology clerkship student director. Dr Albin: Dr. Frey, I feel like this was one of the things I actually had no exposure to as a resident. For trainees that kind of want to get a better understanding of how these are managed, what kind of counseling you do, what kind of interventions you're using, how can they get a little bit more exposure? Dr Frey: That's a great question, and I actually had a similar experience to you. I did not see that many patients with Tourette syndrome while I was in my residency training. I got a lot more exposure during my fellowship training, and that's when I actually fell in love with that patient population, caring for them, seeing them be successful. I think it depends on the program that you're in. During the pediatric neurology rotation might be your best bet to getting exposure to patients with Tourette syndrome, since a lot of them are going to be diagnosed when they're quite young, and sometimes they'll even continue to follow through young adulthood in the pediatric neurology clinic. However, up to 20% of patients with Tourette syndrome will have persistent tics during adulthood. And so, I think it is important for neurology trainees to understand how to manage them, understand what resources are out there. So, if you have an interest in that, absolutely try to follow either in the pediatric neurology department, or if you have a movement disorder program that has a Tourette clinic or has a movement disorder specialist who has an interest in Tourette syndrome, definitely try to hang out with them. Get to know that patient population, and educate yourself as much as you're able to educate the patients as well. Dr Albin: Yeah, I think that's fantastic advice. You wrote a fantastic article, and it covers a lot of ground. And I think let's start at some of the basics. When I think of Tourette syndrome and tics, I think of Tourette syndrome having tics, but maybe not all patients who have tics have Tourette syndrome. And so, I was wondering, A, if you could confirm that's true; and then could you tell us a little bit about some of the diagnostic criteria for each of these conditions? Dr Frey: Sure. So, a tic is a phenomenological description. So basically, what you're seeing is a description of a motor or phonic tic, which is a particular type of movement disorder. Tourette syndrome is a very specific diagnosis, and the diagnostic criteria for Tourette syndrome at this point in time is that you need to have had at least one phonic tic and two or more motor tics over the course of at least a year before the age of eighteen. Dr Albin: Got it. So, there's certainly more specific and a lot more criteria for having Tourette syndrome. I was struck in reading your article how many myths there are surrounding Tourette syndrome and tic disorders kind of in general. What's known about the pathophysiology of Tourette syndrome, and what are some common misconceptions about patients who have this disorder? Dr Frey: Yeah, so I think that's a really excellent question because for so many years, Tourette syndrome and tic disorders in general were thought to be psychogenic in origin, even dating back to when they were first described. The history of Tourette syndrome is quite interesting in that, when Tourette---who, you know, it’s named after---was working with Charcot, a lot of the initial descriptors were of actual case reports of patients who had more psychogenic descriptions, and eventually they became known as tic disorders as well. It wasn't until the discovery of Haldol and using Haldol as a treatment for tic disorders that people started to change their perception and say, okay, maybe there is actually a neurologic basis for Tourette syndrome. So, in terms of the pathophysiology, it's not completely known, but what we do know about it, we think that there is some sort of hyperactivity in the corticostriatal-thalamocortical circuits. And we think that because of this hyperactivity, it leads to the hyperactive movement disorder. We think similar circuitry is involved in conditions like OCD, or obsessive compulsive disorder; as well as ADHD, or attention deficit hyperactivity disorder. And because of that, we actually do tend to see an overlap between all three of these conditions in both individuals and families. Dr Albin: And hearing all of that, does this all come back to, sort of, dopamine and, sort of, behavioral motivation, or is it different than that? Dr Frey: It's probably more complex than just dopamine, but there is the thought that dopamine does play a role. And even one of the hypotheses regarding the pathophysiology is actually that these tics might start as habits, and then when the habits become more common, they actually reshape the dopaminergic pathways. And each time a tic occurs, there's a little bit of a dopaminergic reward. And so over time, that reshapes those hyperactive pathways and changes the actual circuitry of the brain, leading it to be not just a habit but part of their neurologic makeup. Dr Albin: It's fascinating to hear how that actually might play into our neural circuitry and, over time, rewire our brain. Fascinating. I mean, this is just so interesting how movement disorders play into such behavioral regulation and some comorbid conditions like ADHD and OCD. I thought it would be really helpful, maybe, to our listeners to kind of think through a case that I suspect is becoming more common. So, if it's okay with you, I'll present sort of a hypothetical. Dr Frey: Absolutely. Dr Albin: This is a father bringing in his seventeen-year-old daughter. She's coming into the clinic because she's been demonstrating, over the past four to six weeks, some jerking movement in her right arm. And it's happened multiple times a day. And it was a pretty sudden onset. She had not had any movement like this before, and then several weeks ago, started moving the right hand. And then it became even more disruptive: her right leg was involved, she had some scrunching her face. This is all happening at a time where she was dealing with some stress, maybe a little bit of applications around college that she was having a lot of anxiety about. How do you sort of approach this case if this is someone who comes to your office? Dr Frey: Sure. So, I think the first thing that you want to get is a good solid history, trying to understand, what is the origin of these abnormal movements and what led to the abnormal movements. Now, a key thing here is that in Tourette syndrome, and most physiologic tic syndromes, there's a pretty early onset. So, in Tourette syndrome, the expected age of onset is between the ages of five and seven years old. So, to have kind of acute new abnormal movements as a seventeen-year-old would be very unusual for a new-onset diagnosis of Tourette syndrome. However, there's a couple of things from the history that could help you. One would be, were there ever tics in the past? Because sometimes, when you think retrospectively, a lot of these patients might have had a simple eye-blinking tic or a coughing tic when they were a child. And perhaps they did have Tourette syndrome, a very mild case of it. But because the tics were never that pronounced, they never went to see anyone about it and it was never known that they had Tourette syndrome in the first place. If there is no history like that and the movements are completely new, out of the blue, of course you want to rule out anything acute that could be going on that could be causing that. Looking at the phenomenology of the movements can also be very helpful. When you're looking at abnormal tic movements, you would expect most cases of som

Ataxia is a neurologic symptom that refers to incoordination of voluntary movement, typically causing gait dysfunction and imbalance. Genetic testing and counseling can be used to identify the type of ataxia and to assess the risk for unaffected family members. In this episode, Katie Grouse, MD, FAAN, speaks with Theresa A. Zesiewicz, MD, FAAN, author of the article “Ataxia” in the Continuum® August 2025 Movement Disorders issue. Dr. Grouse is a Continuum® Audio interviewer and a clinical assistant professor at the University of California San Francisco in San Francisco, California. Dr. Zesiewicz is a professor of neurology and director at the University of South Florida Ataxia Research Center, and the medical director at the University of South Florida Movement Disorders Neuromodulation Center at the University of South Florida and at the James A. Haley Veteran’s Hospital in Tampa, Florida. Additional Resources Read the article: Ataxia Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Grouse: This is Dr Katie Grouse. Today I'm interviewing Dr Theresa Zesiewicz about her article on ataxia, which appears in the August 2025 Continuum issue on movement disorders. Welcome to the podcast, and please introduce yourself to our audience.  Dr Zesiewicz: Well, thank you, Dr Grouse. I'm Dr Theresa Zesiewicz, otherwise known as Dr Z, and I'm happy to be here. Dr Grouse: I have to say, I really enjoyed reading your article. It was a really great refresher for myself as a general neurologist on the topic of ataxia and a really great reminder on a great framework to approach diagnosis and management. But I wanted to start off by asking what you feel is the key message that you hope our listeners will take away from reading your article. Dr Zesiewicz: Yes, so, thanks. I think one of the key messages is that there has been an explosion and renaissance of genetic testing in the past 10 years that has really revolutionized the field of ataxia and has made diagnosis easier for us, more manageable, and hopefully will lead to treatments in the future. So, I think that's a major step forward for our field in terms of genetic techniques over the last 10 years, and even over the last 30 years. There's just been so many diseases that have been identified genetically. So, I think that's a really important take-home message. The other take-home message is that the first drug to treat Friedreich's ataxia, called omaveloxolone, came about about two years ago. This was also a really landmark discovery. As you know, a lot of these ataxias are very difficult to treat. Dr Grouse: Now pivoting back to thinking about the approach to diagnosis of ataxia, how does the timeline of the onset of ataxia symptoms inform your approach? Dr Zesiewicz: The timeline is important because ataxia can be acute, subacute or chronic in nature. And the timeline is important because, if it's acute, it may mean that the ataxia took place over seconds to hours. This may mean a toxic problem or a hypoxic problem. Whereas a chronic ataxia can occur over many years, and that can inform more of a neurodegenerative or more of a genetic etiology. So, taking a very detailed history on the patient is very important. Sometimes I ask them, what is the last time you remember that you walked normal? And that can be a wedding, that can be a graduation. Just some timeline, some point, that the patient actually walked correctly before they remember having to hold onto a railing or taking extra steps to make sure that they didn't fall down, that they didn't have imbalance. That sometimes that's a good way to ask the patient when is the last time they had a problem. And they can help you to try to figure out how long these symptoms have been going on. Dr Grouse: I really appreciate that advice. I will say that I agree, it can sometimes be really hard to get patients to really think back to when they really started to notice something was different. So, I like the idea of referencing back to a big event that may be more memorable to them. Now, given that framework of, you know, thinking through the timeline, could you walk us through your approach to the evaluation of a patient who presents to your clinic with that balance difficulties once you've established that? Dr Zesiewicz: Sure. So, the first thing is to determine whether the patient truly has ataxia. So, do they have imbalance? Do they have a wide base gait? That's very important because patients come in frequently to your clinic and they'll have balance problems, but they can have knee issues or hip issues, neuropathy, something like that. And sometimes what we say to the residents and the students is, usually ataxia or cerebellar symptoms go together with other problems, like ocular problems are really common in cerebellar syndromes. Or dysmetria, pass pointing, speech disorder like dysarthria. So, not only do you need to look at the gait, but you should look at the other symptoms surrounding the gait to see if you think that the patient actually has a cerebellar syndrome. Or do they have something like a vestibular ataxia which would have more vertigo? Or do they have a sensory ataxia, which would occur if a person closes his eyes or has more ataxia when he or she is in the dark? So, you have to think about what you're looking at is the cerebellar syndrome. And then once we look to see if the patient truly has a cerebellar syndrome, then we look at the age, we look at---as you said before, the timeline. Is this acute, subacute, or chronic? And usually I think of ataxia as falling into three categories. It's either acquired, it's either hereditary, or it's neurodegenerative. It can be hereditary. And if it's not hereditary, is it acquired, or is it something like a multiple system atrophy or a parkinsonism or something like that? So, we try to put that together and start to narrow down on the diagnosis, thinking about those parameters. Dr Grouse: That's really a helpful way to think through it. And it is true, it can get very complex when patients come in with balance difficulties. There's so many things you need to think about, but that is a great way to think about it. Of course, we know that most people who come in to the Movements Disorders clinic are getting MRI scans of their brains. But I'm curious, in which cases of patients with cerebellar ataxia do you find the MRI to be particularly helpful in the diagnosis? Dr Zesiewicz: So, an MRI can be very important. Not always, but- so, something like multiple system atrophy type C where you may see a hot cross bun sign or a pontine hyperintensity on the T2-weighted image, that would be helpful. But of course, that doesn't make the diagnosis. It's something that may help you with the diagnosis. In FXTAS, which is fragile X tremor/ataxia syndrome, the patient may have the middle cerebellar peduncle sign or the symmetric hyperintensity in the middle cerebellar peduncles, which is often visible but not always. Something like Wernicke’s, where you see an abnormality of the mammillary bodies. Wilson's disease, which is quite rare, T2-weighted image may show hyperintensities in the putamen in something like Wilson's disease. Those are the main MRI abnormalities, I think, with ataxia. And then we look at the cerebellum itself. I mean, that seems self-evident, but if you look at a sagittal section of the MRI and you see just a really significant atrophy of the cerebellum, that's going to help you determine whether you really have a cerebellar syndrome. Dr Grouse: That's really encouraging to hear a good message for all of us who sometimes feel like maybe we're missing something. It's good to know that information can always come up down the line to make things more clear. Your article does a great review of spinal cerebellar ataxia, but I found it interesting learning about the more recently described syndrome of SCA 27B. Would you mind telling us more about that and other really common forms of SCA that's good to keep in mind? Dr Zesiewicz: Sure. So, there are now 49 types of spinal cerebellar ataxia that have been identified. The most common are the polyglutamine repeat diseases: so, spinocerebellar ataxia type 3 or type 2, type 6, are probably the most common. One of the most recent spinocerebellar ataxias to be genetically identified and clinically identified is spinocerebellar ataxia 27B. This is caused by a GAA expansion repeat in the first intron of the fibroblast growth factor on chromosome 13. And the symptoms do include ataxia, eye problems, downbeat nystagmus, other nystagmus, vertical, and diplopia. It appears to be a more common form of adult-onset ataxia, and probably more common than was originally thought. It may account for a substantial number of ataxias, like, a substantial percentage of ataxias that we didn't know about. So, this was really a amazing discovery on SCA 27B. Dr Grouse: Now a lot of us I think feel a little anxious when we think about genetic testing for ataxia simply because there's so many forms, things are changing quickly. Do you have a rule of thumb or a kind of a framework that we can think of as we approach how we should be thinking about getting genetic testing for the subset of patients? Dr Zesiewicz: Sure. And I think that this is where age comes into play a lot. So, if you have a child who's 10, 11, or

Chorea describes involuntary movements that are random, abrupt, and unpredictable, flowing from one body part to another. The most common cause of genetic chorea in adults is Huntington disease, which requires comprehensive, multidisciplinary care as well as support for care partners, who may themselves be diagnosed with the disease. In this episode, Aaron Berkowitz, MD, PhD FAAN speaks with Kathryn P. L. Moore, MD, MSc, author of the article “Huntington Disease and Chorea” in the Continuum® August 2025 Movement Disorders issue. Dr. Berkowitz is a Continuum® Audio interviewer and a professor of neurology at the University of California San Francisco in the Department of Neurology in San Francisco, California. Dr. Moore is an assistant professor and director of the Parkinson’s Disease and Movement Disorders Fellowship in the department of neurology at Duke University in Durham, North Carolina. Additional Resources Read the article: Huntington Disease and Chorea Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @AaronLBerkowitz Guest: @KatiePMooreMD Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Berkowitz: This is Dr Aaron Berkowitz with Continuum Audio, and today I'm interviewing Dr Kathryn Moore about her article on diagnosis and management of Huntington disease and chorea, which appears in the August 2025 Continuum issue on movement disorders. Welcome to the podcast, Dr Moore. Could you please introduce yourself to our audience? Dr Moore: Yeah, thank you so much. I'm so excited to be here. I'm Dr Moore. I'm an assistant professor of neurology at Duke University, where I work as a movement disorder specialist. I run our fellowship there and help with our residency program as well. So, I'm excited to speak with our listeners about chorea today. Dr Berkowitz: Fantastic. And we're excited to talk to you about chorea. So, as a general neurologist myself, I only see chorea pretty rarely compared to other movement disorders like tremor, myoclonus, maybe the occasional tic disorder. And like anything I don't see very often, I always have to look up the differential diagnosis and how to evaluate a patient with chorea. So, I was so glad to read your article. And next time I see a patient with chorea, I know I'll be referring to your article as a great reference to have a framework for how to approach it. I hope our readers will look at all these helpful tables on differential diagnosis based on distribution of chorea in the body, potential etiologies, time course of onset and evolution, associated drug-induced causes, what tests to send. So, I highly recommend our listeners read the article. Keep those tables handy for when a patient comes in with chorea. I'm excited to pick your brain about some of these topics today. First, how do you go about distinguishing chorea from other hyperkinetic movement disorders when you see a patient that you think might have chorea? Dr Moore: One of the wonderful things about being a movement disorder specialist is we spend a lot of time looking at movements and training our brain to make these distinctions. The things that I would be looking out for chorea is involuntary, uncontrolled movements that appear to be brief and flowing from one part of the body to another. So, if you can watch a patient and predict what movements they're going to do, this probably isn't chorea. And it should be flowing from one part of the body to another. So, not staying just in one part of the body or having sustained movements. It can be difficult to distinguish between a tic or dystonia or myoclonus. Those things tend to be more predictable and repetitive than the chorea, which tends to be really random and can look like dancing. Dr Berkowitz: That's very helpful. So, once you've decided the patient has chorea, what's your framework for thinking about the differential diagnosis of the cause of the patient's chorea? Dr Moore: Well, that could be really challenging. The differential for chorea is very broad, and so the two things that I tend to use are age of the patient and acuity of onset. And so, if you're thinking about acute onset of chorea, you're really looking at a structural lesion like a stroke or a systemic issue like infection, hyperglycemia, etc. Where a gradually progressive chorea tends to be genetic in nature. When you're thinking about the difference between a child and an adult, the most common cause of chorea in a child is Sydenham's chorea. And actually, the most common cause of chorea that I tend to see is Parkinson's disease medication. So, if anybody's seen dyskinesia in Parkinson's disease, you've seen chorea. But it's those two things that I'm using, the age of the patient and the acuity. Somewhere in the middle, though---so, if you have subacute onset of chorea---it's important to remember to think about autoimmune conditions or paraneoplastic conditions because these are treatable. Dr Berkowitz: That's very helpful. So, like in any chief concern in neurology, we're using the context like the age and then the time course. And then a number of other helpful points in your article about the distribution of chorea in the body. Any comments you'd like to make about- we have this very helpful table that I thought was very interesting. So, you really get deep into the nuances of chorea and the movement disorder specialist expert level. Are there any aspects of parts of the body affected by chorea or distribution of chorea across the body that help you hone your differential diagnosis? Dr Moore: Certainly. I think where the chorea is located in the body can be helpful, but not as helpful as other conditions where you're localizing a lesion or that sort of thing. Because you can have a systemic cause of chorea that causes a hemichorea; that you can have hyperglycemia causing a hemichorea, or even Sydenham's chorea being a hemichorea. But things that we think about, if the forehead is involved, I would think about Huntington’s disease, although this is not pathognomonic. And if it's involving the face or the mouth, you can think about neuroacanthocytosis or, more commonly, tardive dyskinesia. Hemichorea would make me think about some of those systemic issues like hyperglycemia, Sydenham's chorea, those sorts of things, but I would rely more on the historical context and the acuity of presentation than the distribution itself. Dr Berkowitz: Got it. That's very helpful. So those can be helpful features, but not sort of specific for any particular condition. Dr Moore: Exactly. Dr Berkowitz: Yeah, I often see forehead chorea mentioned as sort of specific to Huntington's disease. Since I don't see much Huntington's disease myself, what does forehead chorea look like? What is the forehead doing? How do you recognize that there is chorea of the forehead? It's just sort of hard for me to imagine what it would look like. Dr Moore: It's really tricky. I think seeing the eyebrows go up and down or the brows furrow in an unpredictable way is really what we're looking for. And that can be hard if you're having a conversation. My forehead is certainly animated as we're talking about one of my favorite topics here. One of the tricks that I use with the fellows is to observe the forehead from the side, and there you can see the undulation of the forehead muscles. And that can be helpful as you're looking for these things. I think where it's most helpful to use the forehead is if you're trying to determine if someone with a psychiatric history has tardive dyskinesia or Huntington's disease, because there can be quite a lot of overlap there. And unfortunately, patients can have both conditions. And so, using the forehead movement can be helpful to maybe direct further testing for Huntington's disease. Dr Berkowitz: Oh, wow, that's a very helpful pearl. So, if you see, sort of, diffuse chorea throughout the body and the forehead is involved, to my understanding it may be less specific. But in the context of wondering, is the neuropsychiatric condition and movement disorder related by an underlying cause in the case of seeing orofacial dyskinesias, is the relationship a drug having caused a tardive dyskinesia or is the whole underlying process Huntington's, the absence of forehead might push you a little more towards tardive dyskinesia, presuming there is an appropriate implicated drug and the presence of forehead chorea would really clue you in more to Huntington's. Did I understand that pearl? Dr Moore: That's exactly right, and I'm glad you brought up the point about making sure, if you're considering tardive dyskinesia, that there has been an appropriate drug exposure. Because without that you can't make that diagnosis. Dr Berkowitz: That's a very helpful and interesting pearl, looking at the forehead from the side. That is a movement disorders pearl for sure. Sort of not just looking at the forehead from one angle and trying to figure out what it's doing, but going to look at the patient in profile and trying to sort it out. I love that. Okay. So, based on the differential diagnosis you would have crafted based on whether this is sort of acute, subacute, chronic, the age of the patient, whether it's unilateral, bilateral, which parts of the body. How do you go about the initial evaluation in terms of laboratory testing, imaging, etc.? Dr Moore: Well, certainly in an acute-onset patient, you're going to g

Progressive supranuclear palsy and corticobasal syndrome are closely related neurodegenerative disorders that present with progressive parkinsonism and multiple other features that overlap clinically and neuropathologically. Early recognition is critical to provide appropriate treatment and supportive care. In this episode, Teshamae Monteith, MD, FAAN speaks with Nikolaus R. McFarland, MD, PhD, FAAN, author of the article “Progressive Supranuclear Palsy and Corticobasal Syndrome” in the Continuum® August 2025 Movement Disorders issue. Dr. Monteith is the associate editor of Continuum® Audio and an associate professor of clinical neurology at the University of Miami Miller School of Medicine in Miami, Florida. Dr. McFarland is an associate professor of neurology at the University of Florida College of Medicine at the Norman Fixel Institute for Neurological Diseases in Gainesville, Florida. Additional Resources  Read the article: Progressive Supranuclear Palsy and Corticobasal Syndrome Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @headacheMD Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Monteith: Hi, this is Dr Teshamae Monteith. Today I'm interviewing Dr Nikolaus McFarland about his article on progressive supranuclear palsy and cortical basilar syndrome, which appears in the August 2025 Continuum issue on movement disorders. Welcome, how are you? Dr Farland: I'm great. Thank you for inviting me to do this. This is a great opportunity. I had fun putting this article together, and it’s part of my passion. Dr Monteith: Yes, I know that. You sit on the board with me in the Florida Society of Neurology and I've seen your lectures. You're very passionate about this. And so why don't you first start off with introducing yourself, and then tell us just a little bit about what got you interested in this field. Dr Farland: I'm Dr Nicholas McFarlane. I'm an associate professor at the University of Florida, and I work at the Norman Fixel Institute for Neurological Diseases. I am a director of a number of different centers. So, I actually direct the cure PSP Center of Care and the MSA Center of Excellence at the University of Florida; I also direct the Huntington's clinic there as well. But for many years my focus has been on atypical parkinsonisms. And, you know, I've treated these patients for years, and one of my focuses is actually these patients who suffer from progressive supranuclear palsy and corticobasal syndrome. So that's kind of what this review is all about. Dr Monteith: You probably were born excited, but I want to know what got you interested in this in particular? Dr Farland: So, what got me interested in this in particular was really the disease and the challenges that's involved in it. So, Parkinson's disease is pretty common, and we see a lot of that in our clinic. Yet many times, roughly about 10 to 15% of my patients present with these atypical disorders. And they're quite fascinating. They present in different ways. They're fairly uncommon. They're complex disorders that progress fairly rapidly, and they have multiple different features. They're sort of exciting to see clinically as a neurologist. I think they're really interesting from an academic standpoint, but also in the standpoint of really trying to bring together sort of a team. We have built a multidisciplinary team here at the University of Florida to take care of these patients. They require a number of folks on that team to take care of them. And so, what's exciting, really, is the challenge of treating these patients. There are very limited numbers of therapies that are available, and the current therapies that we have often really aren't great and over time they fail. And so, part of the challenge is actually doing research. And so, there's actually a lot of new research that's been going on in this field. Recently, there's been some revisions to the clinical criteria to help diagnose these disorders. So, that's really what's exciting. The field is really moving forward fairly rapidly with a number of new diagnostics, therapeutics coming out. And hopefully we can make a real difference for these patients. And so that's what really got me into this field, the challenge of trying to treat these patients, help them, advocate for them and make them better. Dr Monteith: And so, tell me what the essential points of this article. Dr Farland: So, the essential points, really, of this article is: number one, you know, just to recognize the new clinical criteria for both PSP and corticobasal syndrome, the diagnosis for these disorders or the phenotypic spectrum has really expanded over the years. So, we now recognize many different phenotypes of these disorders, and the diagnosis has gotten fairly complicated. And so, one of the goals of this article was to review those new diagnostic criteria and the different phenotypic ways these diseases present. I wanted to discuss, also, some of the neuropathology and clinicopathological overlap that's occurred in these diseases as well as some of the new diagnostic tests that are available. That's definitely growing. Some of the new studies that are out, in terms of research and clinical trials. And then wanted to review some of the approaches for treatment for neurologists. Particularly, we're hoping that, you know, this article educates folks. If you're a general neurologist, we're hoping that recognizing these diseases early on will prompt you to refer these patients to specialty clinics or movement disorder specialists early on so they can get appropriate care, confirm your diagnosis, as well as get them involved in trials if they are available. Dr Monteith: And how has the clinical criteria for PSP and cortical basilar syndrome changed? Dr Farland: I think I already mentioned there's been an evolution of the clinical criteria for PSP. There's new diagnostic criteria that were recently published, and it recognizes the multiple clinical phenotypes and the spectrum of the disease that's out there, which is much broader than we thought about. Corticobasal clinical criteria are the Dr Armstrong criteria from 2013. They have not been updated, but they are in the works of being updated. But it does recognize the classic presentation of corticobasal syndrome, plus a frontal executive predominant and then a variant that actually overlaps with PSP. So, there's a lot more overlap in these two diseases than we originally recognized. Dr Monteith: And so, you spoke a bit about FTD spectrum. So why don't you tell us a little bit about what that is? I know you mentioned multiple phenotypes. Dr Farland: What I really want to say is that both PSP and corticobasal syndrome, they're relatively rare, and what- sort of as to common features, they both are progressive Parkinson disorders, but they have variable features. While they're commonly associated with Parkinson's, they also fit within this frontotemporal lobar spectrum, having features that overlap both clinically and neuropathologically. I just want folks to understand that overlap. One of this pathological overlap here is the predominant Tau pathology in the brain, an increasing recognology- recognition of sort of the pathological heterogeneity within these disorders. So, there's an initial description, a classic of PSP, as Richardson syndrome. But now we recognize there are lots of different features to it and there are different ways it presents, and there's definitely a lot of clinical pathological overlap. Dr Monteith: Why don't we just talk about some red flags for PSP? Dr Farland: Yeah, sure. So, some of the red flags for PSP and even corticobasal syndrome are: number one is rapid progression with early onset of falls, gait difficulty, falling typically backwards, early speech and swallow problems that are more prominent than you see in Parkinson's disease, as well as eye gaze issues. So, ocular motor features, particularly vertical gaze palsy. In particular what we talk about is the supranuclear gaze palsy, and one of the most sensitive features that we've seen with these is downgaze limitation or slowed downgaze, and eventually a full vertical gaze palsy and followed supranuclear gaze palsy. So, there's some of the red flags that we see. So, while we think about the lack of response to levodopa frequently as something that's a red flag for Parkinson's, there are many times that we see Parkinson's patients, and about a quarter of them don't really respond. There's some features that don't respond to levodopa that may not be so specific, but also can be helpful in this disease. Dr Monteith: And what about the red flags for cortical basilar syndrome? Dr Farland: So, for cortical basilar syndrome, some of the red flags again are this rapidly depressive syndrome tends to be, at least in its classical present presentation, more asymmetric in its presentation of parkinsonism, with features including things like dystonic features, okay? For limb dystonia and apraxias---so, inability to do a learned behavior. One of those red flags is a patient who comes in and says, my hand doesn't work anymore, which is something extremely uncommon that you hear in Parkinson's disease. Most of those patients will present, say, I might have a tremor, but they very rarely will tell you that I can't use my hand. So look out for that sign. Dr Monteith: And let's talk a little bit

Multiple system atrophy is a rare, sporadic, adult-onset, progressive, and fatal neurodegenerative disease. Accurate and early diagnosis remains challenging because it presents with a variable combination of symptoms across the autonomic, extrapyramidal, cerebellar, and pyramidal systems. Advances in brain imaging, molecular biomarker research, and efforts to develop disease-modifying agents have shown promise to improve diagnosis and treatment. In this episode, Casey Albin, MD speaks with Tao Xie, MD, PhD, author of the article “Multiple System Atrophy” in the Continuum® August 2025 Movement Disorders issue. Dr. Albin is a Continuum® Audio interviewer, associate editor of media engagement, and an assistant professor of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia. Dr. Xie is director of the Movement Disorder Program, chief of the Neurodegenerative Disease Section in the department of neurology at the University of Chicago Medicine in Chicago, Illinois. Additional Resources Read the article: Multiple System Atrophy Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @caseyalbin Full episode transcript available here Dr. Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Albin: Hello everyone, this is Dr Casey Albin. Today I'm interviewing Dr Tao Xie about his article on diagnosis and management of multiple system atrophy, which appears in the August 2025 Continuum issue on movement disorders. Welcome to the podcast, and please introduce yourself to our audience. Dr Xie: Thank you so much, Dr Albin. My name is Tao Xie, and sometimes people also call me Tao Z. I'm a mood disorder neurologist, professor of neurology at the University of Chicago. I'm also in charge of the mood disorder program here, and I'm the section chief in the neurodegenerative disease in the Department of Neurology at the University of Chicago Medicine. Thank you for having me, Dr Albin and Dr Okun and the American Academy of Neurology. This is a great honor and pleasure to be involved in this education session. Dr Albin: We are delighted to have you, and thank you so much for the thoughtful approach to the diagnosis and management. I really want to encourage our listeners to check out this article. You know, one of the things that you emphasize is multiple system atrophy is a fairly rare condition. And I suspect that clinicians and trainees who even have a fair amount of exposure to movement disorders may not have encountered that many cases. And so, I was hoping that you could just start us off and walk us through what defines multiple system atrophy, and then maybe a little bit about how it's different from some of the more commonly encountered movement disorders. Dr Xie: This is a really good question, Dr Albin. Indeed, MSA---multisystem atrophy----is a rare disease. It is sporadic, adult-onset, progressive, fatal neurodegenerative disease. By the name MSA, multisystem atrophy. Clinically, it will present with multiple symptoms and signs involving multiple systems, including symptoms of autonomic dysfunction and symptoms of parkinsonism, which is polyresponsive to the levodopa treatment; and the symptom of cerebellar ataxia, and symptom of spasticity and other motor and nonmotor symptoms. And you may be wondering, what is the cause- underlying cause of these symptoms? Anatomically, we can find the area in the basal ganglia striatonigral system, particularly in the putamen and also in the cerebellar pontine inferior, all of the nuclear area and the specific area involved in the autonomic system in the brain stem and spinal cord: all become smaller. We call it atrophy. Because of the atrophy in this area, they are responsible for the symptom of parkinsonism if it is involved in the putamen and the cerebral ataxia, if it's involved in the pons and cerebral peduncle and the cerebellum. And all other area, if it's involved in the autonomic system can cause autonomic symptoms as well. So that's why we call it multisystem atrophy. And then what's the underlying cellular and subcellular pathological, a hallmark that is in fact caused by misfolded alpha-synuclein aggregate in the oligodontia site known as GCI---glial cytoplasmic increasing bodies---in the cells, and sometimes it can also be found in the neuronal cell as well in those areas, as mentioned, which causes the symptom. But clinically, the patient may not present all the symptoms at the same time. So, based on the predominant clinical symptom, if it's mainly levodopa, polyresponsive parkinsonism, then we call it MSAP. If it's mainly cerebellar ataxia, then we call it MSAC. But whether we call it MSP or MSC, they all got to have autonomic dysfunction. And also as the disease progresses, they can also present both phenotypes together. We call that mixed cerebellar ataxia and parkinsonism in the advanced stage of the disease. So, it is really a complicated disease. The complexity and the similarity to other mood disorders, including parkinsonism and the cerebellar ataxia, make it really difficult sometimes, particularly at the early stages of disease, to differentiate one from the other. So, that was challenging not only for other professionals, general neurologists and even for some movement disorder specialists, that could be difficult particularly if you aim to make an accurate and early diagnosis. Dr Albin: Absolutely. That is such a wealth of knowledge here. And I'm going to distill it just a little bit just to make sure that I understand this right. There is alpha-synuclein depositions, and it's really more widespread than one would see maybe in just Parkinson's disease. And with this, you are having patients present with maybe one of two subtypes of their clinical manifestations, either with a Parkinson's-predominant movement disorder pattern or a cerebellar ataxia type movement disorder pattern. Or maybe even mixed, which really, you know, we have to make things quite complicated, but they are all unified and having this shared importance of autonomic features to the diagnosis. Have I got that all sort of correct? Dr Xie: Correct. You really summarize well. Dr Albin: Fantastic. I mean, this is quite a complicated disease. I would pose to you sort of a case, and I imagine this is quite common to what you see in your clinic. And let's say, you know, a seventy-year-old woman comes to your clinic because she has had rigidity and poor balance. And she's had several falls already, almost always from ground level. And her family tells you she's quite woozy whenever she gets up from the chair and she tends to kind of fall over. But they noticed that she's been stiff,and they've actually brought her to their primary care doctor and he thought that she had Parkinson's disease. So, she started levodopa, but they're coming to you because they think that she probably needs a higher dose. It's just not working out very well for her. So how would you sort of take that history and sort of comb through some of the features that might make you more concerned that the patient actually has undiagnosed multiple systems atrophy? Dr Xie: This is a great case, because we oftentimes can encounter similar cases like this in the clinic. First of all, based on the history you described, it sounds like an atypical parkinsonism based on the slowness, rigidity, stiffness; and particularly the early onset of falls, which is very unusual for typical Parkinson disease. It occurs too early. If its loss of balance, postural instability, and fall occurred within three years of disease onset---usually the motor symptom onset---then it raises a red flag to suspect this must be some atypical Parkinson disorders, including multiple system atrophy. Particularly, pou also mentioned that the patient is poorly responsive to their levodopa therapy, which is very unusual because for Parkinson disease, idiopathic Parkinson disease, we typically expect patients would have a great response to the levodopa, particularly in the first 5 to 7 years. So to put it all together, this could be atypical parkinsonism, and I could not rule out the possibility of MSA. Then I need to check more about other symptoms including autonomic dysfunction, such as orthostatic hypertension, which is a blood pressure drop when the patient stands up from a lying-down position, or other autonomic dysfunctions such as urinary incontinence or severe urinary retention. So, in the meantime, I also have to put the other atypical Parkinson disorder on the differential diagnosis, such as PSP---progressive supranuclear palsy---and the DLBD---dementia with Lewy body disease.---Bear this in mind. So, I want to get more history and more thorough bedside assessment to rule in or rule out my diagnosis and differential diagnosis. Dr Albin: That's super helpful. So, looking for early falls, the prominence of autonomic dysfunction, and then that poor levodopa responsiveness while continuing to sort of keep a very broad differential diagnosis? Dr Xie: Correct. Dr Albin: One of the things that I just have to ask, because I so taken by this, is that you say in the article that some of these patients actually have preservation of smell. In medical school, we always learn that our Parkinson's disease patients kind of had that early loss of smell. Do you find that to be clinically relevant? Is that- does that anecdotally help? Dr Xie: This is a very interesting point because we know th

Essential tremor is the most common movement disorder, although it is often misdiagnosed. A careful history and clinical examination for other neurologic findings, such as bradykinesia, dystonia, or evidence of peripheral neuropathy, can reveal potential alternative etiologies. Knowledge about epidemiology and associated health outcomes is important for counseling and monitoring for physical impairment and disability. In this episode, Lyell Jones, MD, FAAN, speaks with Ludy C. Shih, MD, MMSc, FAAN, author of the article “Essential Tremor” in the Continuum® August 2025 Movement Disorders issue. Dr. Jones is the editor-in-chief of Continuum: Lifelong Learning in Neurology® and is a professor of neurology at Mayo Clinic in Rochester, Minnesota. Dr. Shih is clinical director of the Parkinson's Disease and Movement Disorders Center at Beth Israel Deaconess Medical Center in Boston, Massachusetts. Additional Resources Read the article: Essential Tremor Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @LyellJ Guest: @ludyshihmd Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum: Lifelong Learning in Neurology. Today, I'm interviewing Dr Ludy Shih, who recently authored an article on essential tremor for our latest issue of Continuum on movement disorders. Dr Shih is an associate professor of neurology at Harvard Medical School and the clinical director of the Parkinson's Disease and Movement Disorder Center at Beth Israel Deaconess Medical Center in Boston. Dr Shih, welcome, and thank you for joining us today. Why don't you introduce yourself to our listeners? Dr Shih: Thank you, Dr Jones, for having me. It's a real pleasure to be here on the podcast with you. I'm a neurologist, I trained in movement disorders fellowship, and I currently see patients and conduct clinical research. We offer a variety of treatments and diagnostic tests for our patients with movement disorders. And I have developed this interest, a clinical research interest in essential tremor. Dr Jones: And so, as an expert in essential tremor, the perfect person to write such a really spectacular article. And I can't wait for our listeners to hear more about it and our subscribers to read it. And let's get right to it. If you had, Dr Shih, a single most important message for our listeners about caring for patients with essential tremor, what would that message be? Dr Shih: Yeah, I think the takeaway that I've learned over the years is that people with essential tremor do develop quite a few other symptoms. And although we propose that essential tremor is this pure tremor disorder, they can experience a lot of different comorbidities. Now, there is some debate as to whether that is expected for essential tremor or is this some part of another syndrome, which we may talk about later in the interview. But the fact of the matter is, it's not a benign condition and people do experience some disability from it. Dr Jones: And I think that speaks to how the name of this disorder has evolved over time. right? You point out in your article, it used to be called benign essential tremor or benign familial tremor. But it's really not so straightforward as it. And fairly frequently these symptoms, the patient's tremor, can be functionally limiting, correct? Dr Shih: That is correct. In fact, the reason I probably started getting interested in essential tremor was because our center had been doing a lot of deep brain stimulation for essential tremor, which is remarkably effective, especially for tremor that reaches an amplitude that really no oral medication is going to satisfyingly treat. And if you have enough upper limb disability from this very large-amplitude tremor, a surgical option may make a lot of sense for a lot of patients. And yet, how did they get to that point? Do they continue to progress? These were the sort of interesting questions that got raised in my mind as I started to treat these folks. Dr Jones: We'll come back to treatment in just a minute here, because there are many options, and it sounds like the options are expanding. To start with the diagnosis- I mean, this is an extraordinarily common disorder. As you point out, it is the most common movement disorder in the US and maybe the world, and yet it seems to be underrecognized and frequently misdiagnosed. Why do you think that is? Dr Shih: Great question. It's been pretty consistent, with several case series over the decades showing a fairly high rate of quote/unquote “misdiagnosis.” And I think it speaks to two things, probably. One is that once someone sees a postural and kinetic tremor of the arms, immediately they think of essential tremor because it is quite common. But there's a whole host of things that it could actually be. And the biggest one that we also have to factor in is also the heterogeneity of the presentation of Parkinson's disease. Many people, and I think increasingly now these days, can present with not a whole lot of the other symptoms, but may present with an atypical tremor. And it becomes actually a little hard to sort out, well, do they have enough of these other symptoms for me to suspect Parkinson's, or is the nature of their tremor suspicious enough that it would just be so unusual that this stays essential tremor and doesn't eventually develop into Parkinson’s disease? And I think those are the questions that we all still grapple with from time to time in some of our clinics. Dr Jones: Probably some other things related to it with, you know, our understanding of the pathophysiology and the availability of tests. And I do want to come back to those questions here in just a minute, but, you know, just the nomenclature of this disorder… I think our clinical listeners are familiar with our tendency in medicine to use words like essential or idiopathic to describe disorders or phenomena where we don't understand the precise underlying mechanism. When I'm working with our trainees, I call these “job-security terms” because it sounds less humbling than “you have a tremor and we don't know what causes it,” right? So, your article does a really nice job outlining the absence of a clear monogenic or Mendelian mechanism for essential tremor. Do you think we'll ever have a eureka moment in neurology for this disorder and maybe give it a different name? Dr Shih: It's a great question. I think as we're learning with a lot of our neurologic diseases---and including, I would even say, Parkinson's disease, to which ET gets compared to a lot---there's already now so much more known complexity to something that has a very specific idea and concept in people's minds. So, I tend to think we'll still be in an area where we'll have a lot of different causes of tremor, but I'm hopeful that we'll uncover some new mechanisms for which treating or addressing that mechanism would take care of the tremor in a way that we haven't been able to make as much progress on in the last few decades as maybe we would have thought given all the advances in in technology. Dr Jones: That's very helpful, and we'll be hopeful for that series of discoveries that lead us to that point. I think many of our listeners will be familiar with the utility---and, I think, even for most insurance companies, approval---for DAT scans to discriminate between essential tremor and Parkinsonian disorders. What about lab work? Are there any other disorders that you commonly screen for in patients who you suspect may have essential tremor? Dr Shih: Yeah, it's a great question. And I think, you know, I'm always mindful that what I'm seeing in my clinic may not always be representative of what's seen in the community or out in practice. I'll give an example. You know, most of the time when people come to the academic Medical Center, they're thinking, gosh, I've tried this or that. I've been on these medicines for the last ten years. But I've had essential tremor for twenty years. We get to benefit a little bit from all that history that's been laid down. And so, it's not as likely you're going to misdiagnose it. But once in a while, you'll get someone with tremor that just started a month ago or just started, you know, 2 or 3 months ago. And you have to still be thinking, well, I’ve got to get out of the specialist clinic mindset, and think, well, what else really could this be? And so, while it's true for everybody, moreso in those cases, in those recent onset cases, you really got to be looking for things like medications, electrolyte abnormalities, and new-onset thyroid disorder, for example, thyroid toxicosis. Dr Jones: Very helpful. And your article has a wonderful list of the conditions to consider, including the medications that might be used for those conditions that might result or unmask a tremor of a different cause. And I think being open-minded and not anchoring on essential tremor just because it's common, I think is a is a key point here. And another feature in your article that I really enjoyed was your step-by-step approach to tremor. What are those steps? Dr Shih: Well, I think you know first of all, tremor is such common terminology that even lay people, patients, nonclinicians will use the word “tremor.” And so, it can be tempting when the notes on your schedule says referred for tremor to sort of immediately jump to that. I think the first step is

Parkinson disease is a neurodegenerative movement disorder that is increasing in prevalence as the population ages. The symptoms and rate of progression are clinically heterogenous, and medical management is focused on the individual needs of the patient. In this episode, Kait Nevel MD, speaks with Ashley Rawls, MD, MS, author of the article “Parkinson Disease” in the Continuum® August 2025 Movement Disorders issue. Dr. Nevel is a Continuum® Audio interviewer and a neurologist and neuro-oncologist at Indiana University School of Medicine in Indianapolis, Indiana. Dr. Rawls is an assistant professor at the University of Florida Health, Department of Neurology at the Norman Fixel Institute for Neurological Diseases in Gainesville, Florida Additional Resources Read the article:  Parkinson Disease Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @IUneurodocmom Guest: @DrRawlsMoveMD Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Nevel: Hello, this is Dr Kait Nevel. Today I'm interviewing Dr Ashley Rawls about her article on Parkinson disease, which appears in the August 2025 Continuum issue on movement disorders. Ashley, welcome to the podcast, and please introduce yourself to the audience. Dr Rawls: Thank you, Kait. Hello everyone, my name is Dr Ashley Rawls. I am a movement disorder specialist at the University of Florida Fixel Institute for Neurologic Diseases in Gainesville, Florida. It's a pleasure to be here. Dr Nevel: Awesome. To start us off talking about your article, can you share what you think is the most important takeaway for the practicing neurologist? Dr Rawls: Yes. I would say that my most important takeaway for this article is that Parkinson disease remains a clinical diagnosis. I think the field has really been advancing and trying to find a biomarker to help with diagnosis through ancillary testing. For example, with the dopamine transporter, the DAT scan, an alpha-synuclein skin biopsy, an alpha-synuclein amplification assay that can happen in blood and CSF. However, I think it's so critical to make sure that you have a very strong history and a very thorough physical exam and use those biomarkers or other testing to help with, kind of, bolstering your thoughts on what's going on with the patient. Dr Nevel: Great. And I can't wait to talk a little bit more about the ancillary testing and how you use that. Before we get to that, can you review with us some of the components of the clinical diagnosis of Parkinson disease? Dr Rawls: Yes. So, when I think about a person that comes in that might have a neurodegenerative disease, I think about two different features, mainly: both motor and Manon motor. So, for my motor features, I'm thinking about resting tremor, bradykinesia---which is fullness of movement with decrement over time---rigidity, and then a specific gait disturbance, a Parkinsonian gait, involving stooped posture, decreased arm swing. They can also have reemergent tremor while walking if they do have tremor as part of their disease process, and also in-block turning as they are walking down the hallway. So, those are my motor features that I look for. So now, when we're talking about a specific diagnosis of Parkinson disease, the one motor feature that you need to have is bradykinesia. The reason why I make sure to speak about bradykinesia, which is slowness of movement with decrement over time, is because people can still have Parkinson disease without having tremor, a resting tremor. So even though that's one of the core cardinal features that most of us will be able to notice very readily, you don't have to necessarily have a resting tremor to be diagnosed with Parkinson' disease. When I talk about nonmotor features, those are going to be the three, particularly the prodromal features that can occur even ten years before people have motor features, can be very prominent early on in the disease process. For example, hyposmia or anosmia for decrease or lack of sense of smell. Another one that we really look for is going to be RBD, or rapid eye movement behavior disorder; or REM behavior disorder, the person acting out their dreams, calling out, flailing their limbs, hitting their bed partner. And then the other one is going to be severe constipation. So those three prodromal nonmotor symptoms of hyposmia/anosmia, RBD or REM behavior disorder, and severe constipation can also make me concerned as a red flag that there is a sort of neurodegenerative issue like a Parkinson disease that may be going on with the patient. Dr Nevel: Great, thank you so much for that overview. While we're talking about the diagnosis, do you mind kind of going back to what you mentioned in the beginning and talking about the ancillary tests that sometimes are used to kind of help, again, bolster that diagnosis of Parkinson disease? You know, like the DAT or the alpha-synuclein skin biopsy. When should we be using those? Should we be getting these on everyone? And what scenarios should we really consider doing one of those tests? Dr Rawls: The scenario in which I would order one of the ancillary testing, particularly like a DAT scan or a skin biopsy, looking for alpha-synuclein is going to be when there are potential red flags or a little bit of confusion in regard to the history and physical that I need to have a little bit more clarification on. For example, if I have a patient that has a history of using dopamine blocking agents, for example, for severe depression; or they have a history of cancer diagnosis and they've been on a dopamine agent like metoclopramide; those I want to be mindful because if they're coming in to see me and they're having the symptoms of Parkinsonism---which is going to be resting tremor, bradykinesia rigidity, or gait disturbance---I need to try to figure out is it potentially due to a medication effect, particularly if they're still on the dopamine blockade medication, or is it something where they're actually having a neurodegenerative illness underneath it, like a Parkinson disease? The other situation that would make me order a DAT skin or a skin biopsy is going to be someone who is coming in that maybe has elements of essential tremor, they have more of a postural or an intention tremor that's very flapping and larger amplitude, and maybe have some mild symptoms and Parkinsonism that might be difficult to distinguish between other musculoskeletal things like arthritis, other imbalance issues from, you know, hip problems or knee problems and what have you. Then I might say, okay, let's see if there is some sort of neurodegeneration underneath this; that may be- that there could be, you know, potentially two elements like a central tremor and Parkinson disease going on. Or is this someone who actually really has Parkinson disease, but there's other factors that are kind of playing into that. Dr Nevel: Great, thank you for that. Gosh, things have really changed over the past fifteen years or so where we have this ancillary testing that we're able to use more, because what you read in the textbook isn't always what you see in clinic. And as you described, there are patients who… it's not as clear cut, and these tests can be helpful. Could you tell us more about the levodopa challenge test? How is this useful in clinical practice? And what are some key points that we should know about when utilizing this strategy for patients who we think have Parkinson disease? Dr Rawls: So, before we had all this ancillary testing with the DAT scan, the skin biopsy, the alpha-synuclein amplification assay, many times if you had a suspicion that a person that had Parkinson disease, but you weren't entirely sure, you would say, hey, listen, let us give you back the dopamine that your body may be missing and see if you have an improvement, in particular in your motor symptom. So, when I talk with my patients, I say, listen, I might have a strong suspicion that you have Parkinson disease. Doing a levodopa trial can not only be diagnostic, but also can be therapeutic as well. So, with this levodopa trial, what I end up doing is saying, okay, we're going to start the medication at a low dose because we are looking to see if you have improvement in three of the main cardinal motor symptoms. Obviously, tremor is much easier for us to see if it gets better. It's very obvious on exam, and the patients are more readily able to see it. Whereas stiffness and slowness is much harder to quantify and try to figure out. Am I stiff and slow because of potential muscle tightness from Parkinson disease, or is it something that's more of a musculoskeletal issue? So, I will tell persons, okay, we're looking for improvement in these three cardinal motor symptoms, and things that we're looking for is getting into and out of a car, into and out of a chair, turning over in bed, seeing how do we navigate ourselves in our daily lives? I give people the example of going through the grocery store, going through a busy airport. Are we able to move better and respond better to different changes in our environment which can give us a better clue of if our stiffness and slowness in particular are being improved with the medication? The other part of this is talking about potential side effects of the carbidopa- of the levodopa in particular. One big thing that I think limits people initially is going to be the nausea, vomiting

In this episode, Lyell K. Jones Jr, MD, FAAN, speaks with Michael S. Okun, MD, FAAN, who served as the guest editor of the August 2025 Movement Disorders issue. They provide a preview of the issue, which publishes on August 1, 2025. Dr. Jones is the editor-in-chief of Continuum: Lifelong Learning in Neurology® and is a professor of neurology at Mayo Clinic in Rochester, Minnesota. Dr. Okun is the director at Norman Fixel Institute for Neurological Diseases and distinguished professor of neurology at University of Florida in Gainesville, Florida. Additional Resources Read the issue: continuum.aan.com Subscribe to Continuum®: shop.lww.com/Continuum Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @LyellJ Guest: @MichaelOkun Full episode transcript available here: Dr Jones: Our ability to move through the world is one of the essential functions of our nervous system. Gross movements like walking ranging down to fine movements with our eyes and our hands, our ability to create and coordinate movement is something many of us take for granted. So what do we do when those movements stop working as we intend? Today I have the opportunity to speak with one of the world's leading experts on movement disorders, Dr Michael Okun, about the latest issue of Continuum on Movement Disorders. Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about subscribing to the journal, listening to verbatim recordings of the articles, and exclusive access to interviews not featured on the podcast. Dr Jones: This is Dr Lyle Jones, Editor-in-Chief of Continuum: Lifelong Learning in Neurology. Today, I'm interviewing Dr Michael Okun, who is Continuum's guest editor for our latest issue on movement disorders. Dr Okun is the Adelaide Lackner Distinguished Professor of Neurology at the University of Florida in Gainesville, where he's also the director of the Norman Fixel Institute for Neurological Diseases. Dr Okun, welcome, and thank you for joining us today. Why don't you introduce yourselves to our listeners?  Dr Okun: It's great to be here today. And I'm a neurologist. Everybody who knows me knows I'm pretty simple. I believe the patient's the sun and we should always orbit around the person with disease, and so that's how I look at my practice. And I know we always participate in a lot of research, and I've got a research lab and all those things. But to me, it's always the patients and the families first. So, it'll be great to have that discussion today.  Dr Jones: Yeah, thank you for that, Dr Oaken. Obviously, movement disorders is a huge part of our field of neurology. There are many highly prevalent conditions that fit into this category that most of our listeners will be familiar with: idiopathic Parkinson's disease, essential tremor, tic disorders and so on. And having worked with trainees for a long time, it's one of the areas that I see a lot of trainees gravitate to movement disorders. And I think it's in part because of the prevalence; I think it's in part because of the diversity of the specialty with treatment options and DBS and Botox. But it's also the centrality of the neurologic exam, right? That's- the clinical examination of the patient is so fundamental. And we'll cover a lot of topics today with some questions that I have for you about biomarkers and new developments in the field. But is that your sense too, that people are drawn to just the old-fashioned, essential focus on the neurologic encounter and the neurologic exam? Dr Okun: I believe that is one of the draws to the field of movement. I think that you have neurologists from all over the world that are really interested and fascinated with what things look like. And when you see something that's a little bit, you know, off the normal road or off the normal beaten path… and we are always curious. And so, I got into movement disorders, I think, accidentally; I think even as a child, I was looking at people who had abnormal movements and tremors and I was very fascinated as to why those things happened and what's going on in the brain. And, you know, what are the symptoms and the signs. And then later on, even as my own career developed, that black bag was so great as a neurologist. I mean, it makes us so much more powerful than any of the other clinicians---at least in my biased opinion---out on the wards and out in the clinic. And, you know, knowing the signs and the symptoms, knowing how to do a neurological examination and really walking through the phenomenology, what people look like, you know, which is different than the geno- you know, the genotypes, what the genes are. What people look like is so much more important as clinicians. And so, I think that movement disorders is just the specialty for that, at least in my opinion. Dr Jones: And it helps bring it back to the patient. And that's something that I saw coming through the articles in this issue. And let's get right to it. You've had a chance to review all these articles on all these different topics across the entire field of movement disorders. As you look at that survey of the field, Dr Okun, what do you think is the most exciting recent development for patients with movement disorders?  Dr Okun: I think that when you look across all of the different specialties, what you're seeing is a shift. And the shift is that, you know, a lot of people used to talk in our generation about neurology being one of these “diagnose and adios” specialties. You make the diagnosis and there's nothing that you can do, you know, about these diseases. And boy, that has changed. I mean, we have really blown it out of the water. And when you look at the topics and what people are writing about now and the Continuum issue, and we compare that the last several Continuum issues on movement disorders, we just keep accumulating a knowledge base about what these things look like and how we can treat them. And when we start thinking about, you know, all of the emergence of the autoimmune disorders and identifying the right one and getting something that's quite treatable. Back in my day, and in your day, Lyle, we saw these things and we didn't know what they were. And now we have antibodies, now we can identify them, we can pin them down, and we can treat many of them and really change people's lives. And so, I'm really impressed at what I see in changes in identification of autoimmune disorders, of channelopathies and some of the more rare things, but I'm also impressed with just the fundamental principles of how we're teaching people to be better clinicians in diseases like Parkinson’s, Huntington's, ataxia, and Tourette. And so, my enthusiasm for this issue of Continuum is both on, you know, the cutting edge of what we're seeing based on the identification on our exams, what we can do for these people, but also the emergence of how we're shifting and providing much better care across a continuum for folks with basal ganglia diseases. Dr Jones: Yeah, I appreciate that perspective, Dr Okun. One of the common themes that I saw in the issue was with these new developments, right, when you have new tools like new diagnostic biomarker tools, is the question of if and when and how to integrate those into daily clinical practice, right? So, we've had imaging biomarkers for a while, DAT scans, etc. For patients with idiopathic Parkinson disease, one of the things that I hear a lot of discussion and controversy about are the seed amplification assays as diagnostic biomarkers. What can you tell us about those? Are those ready for routine clinical use yet?  Dr Okun: I think the main bottom-line point for folks that are out there trying to practice neurology, either in general clinics or even in specialty clinics, is to know that there is this movement toward, can we biologically classify a disease? One of the things that has, you know, really accelerated that effort has been the development of these seed amplification assays, which---in short for people who are listening---are basically, we “shake and bake” these things. You know? We shake them for like 20 hours and we use these prionlike proteins, and we learn from diseases like prion disease how to kind of tag these things and then see, do they have degenerative properties? And in the case of Parkinson's disease, we're able to do this with synuclein. That is the idea of a seed amplification assay. We're able to use this to see, hey, is there synuclein present or not in this sample? And people are looking at things like cerebrospinal fluid, they're looking at things like blood and saliva, and they're finding it. The challenge here is that, remember- and one of the things that's great about this issue of Continuum is, remember, there are a whole bunch of different synucleinopathies. So, Dr Jones, it isn't just Parkinson's disease. So, you've got Parkinson's disease, you've got Lewy body, you know, and dementia with Lewy bodies. You've got, you know, multiple system atrophy is within that synucleinopathy, you know, group primary autonomic failure… so not just Parkinson's disease. And so, I think we have to tap the brakes as clinicians and just say, we are where we are. We are moving in that direction. And remember that a seed amplification assay gives you some information, but it doesn't give you all the information. It doesn't forgive you looking at a person over time, examining them in your clinic, seeing how they progress, seeing their response to dopamine- and by the way, several of these genes that are associated with Parkinson; and there's, you know, less than 20% of Parkinson is genetic, but several of these genes, in a solid third---and in some ca

With the increase in the public’s attention to all aspects of brain health, neurologists need to understand their role in raising awareness, advocating for preventive strategies, and promoting brain health for all. To achieve brain health equity, neurologists must integrate culturally sensitive care approaches, develop adapted assessment tools, improve professional and public educational materials, and continually innovate interventions to meet the diverse needs of our communities. In this BONUS episode, Casey Albin, MD, speaks with Daniel José Correa, MD, MSc, FAAN and Rana R. Said, MD, FAAN, coauthors of the article “Bridging the Gap Between Brain Health Guidelines and Real-world Implementation” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Albin is a Continuum® Audio interviewer, associate editor of media engagement, and an assistant professor of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia. Dr. Correa is the associate dean for community engagement and outreach and an associate professor of neurology at the Albert Einstein College of Medicine Division of Clinical Neurophysiology in the Saul Korey Department of Neurology at the Montefiore Medical Center, New York, New York. Dr. Said is a professor of pediatrics and neurology, the director of education, and an associate clinical chief in the division of pediatric neurology at the University of Texas Southwest Medical Center in Dallas, Texas. Additional Resources Read the article: Bridging the Gap Between Brain Health Guidelines and Real-world Implementation Subscribe to Continuum®: shop.lww.com/Continuum Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @caseyalbin Guests: @NeuroDrCorrea, @RanaSaidMD Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. This exclusive Continuum Audio interview is available only to you, our subscribers. We hope you enjoy it. Thank you for listening. Dr Albin: Hi all, this is Dr Casey Albin. Today I'm interviewing Dr Daniel Correa and Dr Rana Said about their article on bridging the gap between brain health guidelines and real-world implementation, which they wrote with Dr Justin Jordan. This article appears in the June 2025 Continuum issue on disorders of CSF dynamics. Thank you both so much for joining us. I'd love to just start by having you guys introduce yourselves to our listeners. Rana, do you mind going first? Dr Said: Yeah, sure. Thanks, Casey. So, my name is Rana Said. I'm a professor of pediatrics and neurology at the University of Texas Southwestern Medical Center in Dallas. Most of my practice is pediatric epilepsy. I'm also the associate clinical chief and the director of education for our division. And in my newer role, I am the vice chair of the Brain Health Committee for the American Academy of Neurology. Dr Albin: Absolutely. So just the right person to talk about this. And Daniel, some of our listeners may know you already from the Brain and Life podcast, but please introduce yourself again. Dr Correa: Thank you so much, Casey for including us and then highlighting this article. So yes, as you said, I'm the editor and the cohost for the Brain and Life podcast. I do also work with Rana and all the great members of the Brain Health Initiative and committee within the AAN, but in my day-to-day at my institution, I'm an associate professor of neurology at the Albert Einstein College of Medicine in the Montefiore Health System. I do a mix of general neurology and epilepsy and with a portion of my time, I also work as an associate Dean at the Albert Einstein College of Medicine, supporting students and trainees with community engagement and outreach activities. Dr Albin: Excellent. Thank you guys both so much for taking the time to be here. You know, brain health has really become this core mission of the AAN. Many listeners probably know that it's actually even part of the AAN’s mission statement, which is to enhance member career fulfillment and promote brain health for all. And I think a lot of us have this kind of, like, vague idea about what brain health is, but I'd love to just start by having a shared mental model. So, Rana, can you tell us what do you mean when you talk about brain health? Dr Said: Yeah, thanks for asking that question. And, you know, even as a group, we really took quite a while to solidify, like, what does that even mean? Really, the concept is that we're shifting from a disease-focused model, which we see whatever disorder comes in our doors, to a preventative approach, recognizing that there's a tremendous interconnectedness between our physical health, our mental health, cognitive and social health, you know, maintaining our optimal brain function. And another very important part of this is that it's across the entire lifespan. So hopefully that sort of solidifies how we are thinking about brain health. Dr Albin: Right. Daniel, anything else to add to that? Dr Correa: One thing I've really liked about this, you know, the evolution of the 2023 definition from the AAN is its highlight on it being a continuous state. We're not only just talking about prevention of injury and a neurologic condition, but then really optimizing our own health and our ability to engage in our communities afterwards, and that there's always an opportunity for improvement of our brain health. Dr Albin: I love that. And I really felt like in this article, you walked us through some tangible pillars that support the development and maintenance of this lifelong process of maintaining and developing brain health. And so, Daniel, I was wondering, you know, we could take probably the entire time just to talk about the five pillars that support brain health. But can you give us a pretty brief overview of what those are that you outlined in this article? Dr Correa: I mean, this was one of the biggest challenges and really bundling all the possibilities and the evidence that's out there and just getting a sense of practical movement forward. So, there are many organizations and groups out there that have formed pillars, whether we're calling them seven or eight, you know, the exact number can vary, but just to have something to stand on and move forward. We've bundled one of them as physical and sleep health. So really encouraging towards levels of activity and not taking it as, oh, that there's a set- you know, there are recommendations out there for amount of activity, but really looking at, can we challenge people to just start growing and moving forward at their current ability? Can we challenge people to look at their sleep health, see if there's an aspect to improve, and then reassess with time? We particularly highlight the importance of mental health, whether it's before a neurologic condition or a brain injury occurs or addressing the mental health comorbidities that may come along with neurologic conditions. Then there's of course the thing that everyone thinks about, I think, with brain health in terms of is cognitive health. And you know, I think that's the first place that really enters either our own minds or as we are observers of our elder individuals in our family. And more and more there has been the highlight on the need for social interconnectedness, community purpose. And this is what we include as a pillar of social health. And then across all types of neurologic potential injuries is really focusing on the area of brain injury. And so, I think the area that we've often been focused as neurologists, but also thinking of both the prevention along with the management of the condition or the injury after it occurs. Dr Albin: Rana, anything else to add to that? That’s a fantastic overview. Dr Said: Daniel, thank you for- I mean, you just set it up so beautifully. I think the other thing that maybe would be important for people to understand is that as we're talking through a lot of these, these are individual. These sound like very individual-basis factors. But as part of the full conversation, we also have to understand that there are some factors that are not based on the individual, and then that leads to some of the other initiatives that we'll be talking about at the community and policy levels. So, for example, if an individual is living in an area with high air pollution. Yes, we want them to be healthy and exercise and sleep, but how do we modify those factors? What about lead leaching from our aging pipes or even infectious diseases? So, I think that outside of our pillars, this is sort of the next step is to understand what is also at large in our communities. Dr Albin: That's a really awesome point. I love that the article really does shine through and that there are these individual factors, and then there there's social factors, there’s policy factors. I want to start just with that individual because I think so many of our patients probably know, like, stress management, exercise, sleep, all of that stuff is really important. But when I was reading your article, what was not so obvious to me was, what's the role that we as neurologists should play in advocating? And really more importantly, like, how should we do that? And again, it struck me that there are these kind of two issues at play. And one is that what Daniel was saying that, you know, a lot of our patients are coming because they have a problem, right? We are used to operating in this disease-based care, and there's just limited time, competing clinical demands. If they're not coming to talk about prevention, how do we bring that in? And so Rana, maybe I'll start with you just for that question, you know, for the patients who are seeing us with a disease complaint or they're coming for the management of a

Childhood-onset hydrocephalus encompasses a wide range of disorders with varying clinical implications. There are numerous causes of symptomatic hydrocephalus in neonates, infants, and children, and each predicts the typical clinical course across the lifespan. Etiology and age of onset impact the lifelong management of individuals living with childhood-onset hydrocephalus. In this episode, Casey Albin, MD, speaks with Shenandoah Robinson, MD, FAANS, FAAP, FACS, author of the article “Childhood-onset Hydrocephalus” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Albin is a Continuum® Audio interviewer, associate editor of media engagement, and an assistant professor of neurology and neurosurgery at Emory University School of Medicine in Atlanta, Georgia. Dr. Robinson is a professor of neurosurgery, neurology, and pediatrics at Johns Hopkins University School of Medicine in Baltimore, Maryland. Additional Resources Read the article: Childhood-onset Hydrocephalus Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @caseyalbin Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Albin: Hi, this is Dr Casey Albin. Today I'm interviewing Dr Shenandoah Robinson about her article on childhood onset hydrocephalus, which appears in the June 2025 Continuum issue on disorders of CSF dynamics. Dr Robinson, thank you so much for being here. Welcome to the podcast. I'd love to start by just having you briefly introduce yourself to our audience. Dr Robinson: I'm a pediatric neurosurgeon at Johns Hopkins, and I'm very fortunate to care for kids and children from the neonatal intensive care unit all the way up through young adulthood. And I have a strong interest in developing better treatments for hydrocephalus. Dr Albin: Absolutely. And this was a great article because I really do think that understanding how children with hydrocephalus are treated really does inform how we can care for them throughout the continuum of their lifespan. You know, I was shocked in reading your article about the scope of the problem for childhood onset hydrocephalus. Can you walk our listeners through what are the most common reasons why CSF diversion is needed in the pediatric population? Dr Robinson: For the United States, and Canada too, the most common reasons are spina bifida---so, a baby that's born with a myelomeningocele and then develops associated hydrocephalus---and then about equally as common is posthemorrhagic hydrocephalus of prematurity, congenital causes such as from aquaductal stenosis, and other genetic causes are less common. And then we also have kids that develop hydrocephalus after trauma or meningitis or tumors or other sort of acquired problems during childhood. Dr Albin: So, it's a really diverse and sort of heterogeneous causes that across sort of the, you know, the neonatal period all the way to, you know, young adulthood. And I'm sure that those etiologies really shift based on sort of the subgroup population that you're talking about. Dr Robinson: Yes, they definitely shift over time. Fortunately for our kids that are born with problems that raise concerns, such as myelomeningocele or if they're born preterm, they sort of declare themselves by the time they're a year old. So, if you're an adult provider, they should have defined themselves and it's unlikely that they will suddenly develop hydrocephalus as a teenager or older adult. Dr Albin: Totally makes sense. I think many of the listeners to this podcast are adult neurologists who are probably very familiar with external ventriculostomies for temporary CSF diversion, and with the more permanent ventricular peritoneal shines or ventricular atrial or plural shines that are needed when there's the need for permanent diversion. But you described in your article two procedures that provide temporary CSF diversion that I think many of our listeners are probably not as familiar with, which is the ventricular access devices and ventriculosubgaleal shunts. Can you briefly describe what those procedures provide? Who are the candidates for them? And then what complications neurologists may need to think about if they're consulted for comanagement in one of these complex patients? Dr Robinson: Well, the good thing is that if as an adult neurologist you encounter someone with, you know, residual tubing from one of these procedures, you are unlikely to need to do anything about it. So, we put in ventricular access device or ventriculosubgaleal shunts, usually in newborns or infants. And sometimes when they no longer need the device, we just leave it in because that saves them an extra surgery. So, if you encounter one later on, it's most likely you won't need to do anything. Often if the baby goes on to show that they need a permanent shunt, we go ahead and put in that permanent shunt. We may or may not go back and take out the reservoir or the subgaleal shunt. The reservoir and subgaleal shunts are often put in the frontal location. Sometimes we'll put the permanent shunt in the occipital location and just leave the residual tubing there. So, you're very unlikely to need to intervene with a reservoir or subgaleal shunt if you encounter an older child or adult with that left in. We use these in the small babies because the external ventricular drains that we're very familiar with have a very high complication rate in this population. In the adult ICU, you often see these, and maybe there's, you know, a few percent risk of infection. It actually heads into 20 to 25% in our preterm infants and other newborns that require one of these devices for drainage. So, we try not to use external ventricular drains like we use in older patients. We use the internalized device: either the ventricular reservoir with a little area for us to tap every day, every other day; or the ventriculosubgaleal shunt, which diverts the spinal fluid to a pocket in the scalp. So, we use these in preterm infants that are too tiny for a permanent shunt. And for some of our babies that are born, for example, with an omphalocele, that we can't use their peritoneal cavity and so we need some temporizing device to manage their CSF. Dr Albin: Totally makes sense. And so just to clarify, I mean, this is a tube that's placed into the ventricles of the brain and then it's tunneled into the subgaleal space and the collection, the CSF, just builds up there, like? Dr Robinson: Yeah. Dr Albin: And over time either, you know, the baby will learn how to account for that extra CSF, and then I guess it's just reabsorbed? Dr Robinson: Yeah. When it's present, though, it looks like maybe, I don't know if you're familiar with like a tissue expander. There is this bubble of fluid under the scalp, but it's prominent, it can be several centimeters in diameter. Dr Albin: Wow, that's just absolutely fascinating. And I don't think I've ever had the opportunity to see this in clinical practice. I've really learned quite a bit about this. I assume that these children are going to go on to get some sort of permanent diversion. And then, you know, over time, those permanent shunts do create a lot of problems. And so, I was hoping you could kind of walk us through, you know, what are some of the things that you're seeing that you're concerned about? And then if you've just inherited a patient who had a shunt placed at, say, a different institution, how do you go about figuring out what kind of shunt it is and if they're still dependent on it? Dr Robinson: There's a few things that, fortunately, technology is helping with. So, it is much easier now for patients to get their images uploaded to image-sharing software, and then we can download their images into our institutional software, which is very helpful. Another option is that we are strongly encouraging our families to use a app such as HydroAssist that's available from the Hydrocephalus Association. So that's an app that goes on your phone, and you can upload the images from an MRI or a CT scan or x-rays from a shunt series. And then that you can take if you're traveling and you have to go to emergency department or you're establishing care with a new provider, you can have your information right there and not be under stress to remember it. It also has areas so you can record the type of valve. And all of our valves have pluses and minuses, they all tend to malfunction a little bit. And they can be particularly helpful with different types of hydrocephalus. I really doubt that we're going to narrow down from the fifteen or so valves we have access to now. And so, recording your valve type, the manufacturer as well as the setting, is very helpful when you're transferring care or if you're traveling and then have to, unfortunately, stop in the emergency department. Dr Albin: Yeah, I thought that was a really great pearl that, like, families now are empowered to sort of take control of understanding sort of the devices that they have, the settings that they're using. And what an incredible thing for providers who are going to care for these patients who, you know, unfortunately do end up in centers that are not their primary center. The other challenge that I find… I practice as a neurointensivist, and sometimes patients come in and they have a history of being shunt dependent and they present with a neurologic change. And I think that we as neurologists can be a little quick

Normal pressure hydrocephalus (NPH) is a pathologic condition whereby excess CSF is retained in and around the brain despite normal intracranial pressure. MRI-safe programmable shunt valves allow for fluid drainage adjustment based on patients’ symptoms and radiographic images. Approximately 75% of patients with NPH improve after shunt surgery regardless of shunt type or location. In this episode, Aaron Berkowitz, MD, PhD, FAAN, speaks with Kaisorn L. Chaichana, MD, author of the article “Management of Normal Pressure Hydrocephalus” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Berkowitz is a Continuum® Audio interviewer and a professor of neurology at the University of California San Francisco in the Department of Neurology in San Francisco, California. Dr. Chaichana is a professor of neurology in the department of neurological surgery at the Mayo Clinic in Jacksonville, Florida. Additional Resources Read the article: Management of Normal Pressure Hydrocephalus Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @LyellJ Guest: @kchaichanamd Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Berkowitz: This is Dr Aaron Berkowitz, and today I'm interviewing Dr Kaisorn Chaichana about his article on management of normal pressure hydrocephalus, which he wrote with Dr Jeremy Cutsforth-Gregory. The article appears in the June 2025 Continuum issue on disorders of CSF dynamics. Welcome to the podcast, and please introduce yourself to our audience. Dr Chaichana: Yeah, thank you for having me. I'm Kaisorn Chaichana. I'm a neurosurgeon at Mayo Clinic in Jacksonville, Florida. Part of my practice is doing hydrocephalus care, which includes shunts for patients with normal pressure hydrocephalus. Dr Berkowitz: Fantastic. Well, before we get into shunt considerations and NPH specifically, which I know is the focus of your article, I thought it would be a great opportunity for a neurologist to pick a neurosurgeon's brain a bit about shunts. So, to start, can you lay out for us the different types of shunts and shunt procedures, the advantages, disadvantages of each type of shunt, how you think about which shunt procedure should be used for which patient, that type of thing? Dr Chaichana: Yeah. So, there are different types of shunts, and the most common one that is used is called a ventricular peritoneal shunt. So, it has a ventricular catheter, it has a catheter that tunnels underneath the skin and it goes into the peritoneum where the fluid goes from the ventricular system into the peritoneum. Typically, the shunts are in the ventricle because that is the largest fluid-filled space in the brain. Other terminal areas include the atrium, which is really the jugular vein, and those are called ventricular atrial shunts. You can also have ventricular pleural shunts, which end in the pleural space and drain flui into the pleural space. Those are pretty much the most common ventricular shunts. There's also a lumboperitoneal shunt that drains from the lumbar spine, similar to a lumbar drain into the peritoneum. For the lumbar shunts, we don't typically have a lumbar pleural or lumbar atrial shunt just because of the pressure dynamics, because the lumbar spine is below the lung and as well as the atrium. And so, the drainage pattern is very different than ventricular peritoneal which is top to bottom. The most common shunt, why we use the ventricular peritoneal shunt the most, is because it has the most control. So, the peritoneum is set at a standard pressure in the intraabdominal pressure, whereas the ventricular atrial shunt depends on your venous return or venous pressure and your ventricular pleural shunt varies with inspiration and expiration. So, the easiest way for us to control the fluid, the ventricular system is through the ventricular peritoneal shunt. And that's why that's our most common shunt that we use. Dr Berkowitz: Fantastic. So, as you mention in the article, neurologists may be reluctant to offer a shunt to patients with NPH because many patients may not improve, or they improve only transiently; and out of fear of shunt complications. So, of course, as neurologists, we often only hear about a patient’s shunt when there is a problem. So, we have this sort of biased view of seeing a lot of shunt malfunction and shunt infection. Of course, we might not see the patient if their shunt is working just fine. How common are these complications in practice, and how do you as a neurosurgeon weigh the risks against the often uncertain or transient benefits of a shunt in a patient with NPH who may be older and multiple medical comorbidities? How do you think about that and talk about it with patients? Dr Chaichana: When you hear about shunt complications, most of the shunt complications you hear about are typically in patients with congenital hydrocephalus. Those patients often require several shunt revisions just from either growing or the shunt stays in for a long time or the ventricular caliber is a lot less than some with normal pressure hydrocephalus. So, we don't really see a lot of complications with normal pressure hydrocephalus. So that shunt placement in these patients is typically pretty safe. The procedure’s a relatively short procedure, around 30 minutes to 45 minutes to place a shunt, and we can control the pressure within the shunt setting so that we don't overdrain---which means too much fluid drains from the ventricular system---which can cause things like a subdural, which is probably the most common complication associated with normal pressure hydrocephalus. So, to obviate those risks, what we do is typically insert the shunt and then keep the shunt setting at a high setting. The higher the setting, the less it drains, and then we bring it slowly down based on the patient's symptoms to try to minimize the risk of this over drainage in the subdural hematoma while at the same time benefiting the patient. So, there's a concern for shunt in patients with normal pressure hydrocephalus. The concern or the complication risks are very low. The problem with normal pressure hydrocephalus, though, is that over time these patients benefit less and less from drainage or their disease process takes over. So, I do recommend placing this shunt as soon as possible just so that we can maximize their quality of life for that period of time. Dr Berkowitz: So, if I'm understanding you, then the risk of complication is more sort of due to the mechanical factors in patients with congenital hydrocephalus or sort of outgrowing the shunt, their pressure dynamics may be changing over time. And in your experience, an older patient with NPH, although they may have more medical comorbidities, the procedure itself is relatively quick and low-risk. And the actual complications due to mechanical factors, my understanding, are just much less common because the patient is obviously fully grown and they're getting one sort of procedure at one point in time and tend to need less revision, have less complication. Is that right? Dr Chaichana: Yeah, that's correct. The complication risk for normal hydrocephalus is a lot less than other types of hydrocephalus. Dr Berkowitz: That's helpful to know. While we're talking about some of these complications, let's say we're following a patient in neurology with NPH who has a shunt. What are some of the symptoms and signs of shunt malfunction or shunt infection? And what are the best studies to order to evaluate for these if we're concerned about them? Dr Chaichana: Yeah. So basically, for shunt malfunction, it’s basically broken down into two categories. It's either overdrainage or underdrainage. So, underdrainage is where the shunt doesn't function enough. And so basically, they return to their state before the shunt was placed. So that could be worsening gait function, memory function, urinary incontinence are the typical symptoms we look for in patients with normal pressure hydrocephalus and underdrainage, or the shunt is not working. For patients that are having overdrainage, which is draining too much, the classic sign is typically headaches when they stand up. And the reason behind that is when there's overdrainage, there's less cerebrospinal fluid in their ventricular system, which means less intracranial pressure. So that when they stand up, the pressure differential between their head and the ground is more than when they're lying down. And because of that pressure differential, they usually have worsening headaches when standing up or sitting up. The other thing are severe headaches, which would be a sign of a subdural hematoma or focality in their neurological symptoms that could point to a subdural hematoma, such as weakness, numbness, speaking problems, depending on the hemisphere. How we work this up is, regardless if you're concerned about overdrainage or underdrainage, we usually start with a CAT scan or an MRI scan. Typically, we prefer a CAT scan because it's quicker, but the CAT scan will show us if the ventricular caliber is the same and/or the placement of the proximal catheter. So, what we look for when we see that CAT scan or that MRI to see the location of the proximal catheter to make sure it hasn't changed from any previous settings. And then we see the caliber of the ventricles. If the caliber of the ventricles is smaller, that could be a sign of overdrainage.

 Normal pressure hydrocephalus (NPH) is a clinical syndrome of gait abnormality, cognitive impairment, and urinary incontinence. Evaluation of CSF dynamics, patterns of fludeoxyglucose (FDG) uptake, and patterns of brain stiffness may aid in the evaluation of challenging cases that lack typical clinical and structural radiographic features. In this episode, Katie Grouse, MD, FAAN, speaks with Aaron Switzer, MD, MSc, author of the article “Radiographic Evaluation of Normal Pressure Hydrocephalus” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Grouse is a Continuum® Audio interviewer and a clinical assistant professor at the University of California San Francisco in San Francisco, California. Dr. Switzer is a clinical assistant professor of neurology in the department of clinical neurosciences at the University of Calgary in Calgary, Alberta, Canada. Additional Resources Read the article: Radiographic Evaluation of Normal Pressure Hydrocephalus Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Grouse: This is Dr Katie Grouse. Today I'm interviewing Dr Aaron Switzer about his article on radiographic evaluation of normal pressure hydrocephalus, which he wrote with Dr Patrice Cogswell. This article appears in the June 2025 Continuum issue on disorders of CSF dynamics. Welcome to the podcast, and please introduce yourself to our audience. Dr. Switzer: Thanks so much for having me, Katie. I'm a neurologist that's working up in Calgary, Alberta, Canada, and I have a special interest in normal pressure hydrocephalus. So, I'm very happy to be here today to talk about the radiographic evaluation of NPH. Dr Grouse: I'm so excited to have you here today. It was really wonderful to read your article. I learned a lot on a topic that is not something that I frequently evaluate in my clinic. So, it's really just a pleasure to have you here to talk about this topic. So, I'd love to start by asking, what is the key message that you hope for neurologists who read your article to take away from it? Dr. Switzer: The diagnosis of NPH can be very difficult, just given the clinical heterogeneity in terms of how people present and what their images look like. And so, I'd like readers to know that detailed review of the patient's imaging can be very helpful to identify those that will clinically improve with shunt surgery. Dr Grouse: There's another really great article in this edition of Continuum that does a really great job delving into the clinical history and exam findings of NPH. So, I don't want to get into that topic necessarily today. However, I'd love to hear how you approach a case of a hypothetical patient, say, where you're suspicious of NPH based on the history and exam. I'd love to talk over how you approach the imaging findings when you obtain an MRI of the brain, as well as any follow-up imaging or testing that you generally recommend. Dr. Switzer: So, I break my approach down into three parts. First, I want to try to identify ventriculomegaly and any signs that would support that, and specifically those that are found in NPH. Secondly, I want to look for any alternative pathology or evidence of alternative pathology to explain the patient's symptoms. And then also evaluate any contraindications for shunt surgery. For the first one, usually I start with measuring Evans index to make sure that it's elevated, but then I want to measure one of the other four measurements that are described in the article, such as posterior colossal angle zed-Evans index---or z-Evans index for the American listeners---to see if there's any other features that can support normal pressure hydrocephalus. It's very important to identify whether there are features of disproportionately enlarged subarachnoid space hydrocephalus, or DESH, which can help identify patients who may respond to shunt surgery. And then if it's really a cloudy clinical picture, it's complicated, it's difficult to know, I would usually go through the full evaluation of the iNPH radscale to calculate a score in order to determine the likelihood that this patient has NPH. So, the second part of my evaluation is to rule out evidence of any alternative pathology to suggest another cause for the patient's symptoms, such as neurodegeneration or cerebrovascular disease. And then the third part of my evaluation is to look for any potential contraindications for shunt surgery, the main one being cerebral microbleed count, as a very high count has been associated with the hemorrhagic complications following shunt surgery. Dr Grouse: You mentioned about your use of the various scales to calculate for NPH, and your article does a great job laying them out and where they can be helpful. Are there any of these scales that can be reasonably relied on to predict the presence of NPH and responsiveness to shunt placement? Dr. Switzer: I think the first thing to acknowledge is that predicting shunt response is still a big problem that is not fully solved in NPH. So, there is not one single imaging feature, or even combination of imaging features, that can reliably predict shunt response. But in my view and in my practice, it's identifying DESH, I think, is really important---so, the disproportionately enlarged subarachnoid space hydrocephalus---as well as measuring the posterior colossal angle. I find those two features to be the most specific. Dr Grouse: Now you mentioned the concept of the NPH subtypes, and while this may be something that many of our listeners are familiar with, I suspect that, like myself when I was reading this article, there are many who maybe have not been keeping up to date on these various subtypes. Could you briefly tell us more about these NPH subtypes? Dr. Switzer: Sure. The Japanese guidelines for NPH have subdivided NPH into three different main categories. So that would be idiopathic, delayed onset congenital, and secondary normal pressure hydrocephalus. And so, I think the first to talk about would be the secondary NPH. We're probably all more familiar with that. That's any sort of pathology that could lead to disruption in CSF dynamics. These are things like, you know, a slow-growing tumor that is obstructing CSF flow or a widespread meningeal process that's reducing absorption of CSF, for instance. So, identifying these can be important because it may offer an alternative treatment for what you're seeing in the patient. The second important one is delayed onset congenital. And when you see an image of one of these subtypes, it's going to be pretty different than the NPH because the ventricles are going to be much larger, the sulcal enfacement is going to be more diffuse. Clinically, you may see that the patients have a higher head circumference. So, the second subtype to know about would be the delayed onset congenital normal pressure hydrocephalus. And when you see an image of one of these subtypes, it's going to be a little different than the imaging of NPH because the ventricles are going to be much larger, the sulcal enfacement is going to be more diffuse. And there are two specific subtypes that I'd like you to know about. The first would be long-standing overt ventriculomegaly of adulthood, or LOVA. And the second would be panventriculomegaly with a wide foramen of magendie and large discernomagna, which is quite a mouthful, so we just call it PAVUM. The importance of identifying these subtypes is that they may be amenable to different types of treatment. For instance, LOVA can be associated with aqueductal stenosis. So, these patients can get better when you treat them with an endoscopic third ventriculostomy, and then you don't need to move ahead with a shunt surgery. And then finally with idiopathic, that's mainly what we're talking about in this article with all of the imaging features. I think the important part about this is that you can have the features of DESH, or you can not have the features of DESH. The way to really define that would be how the patient would respond to a large-volume tap or a lumbar drain in order to define whether they have this idiopathic NPH. Dr Grouse: That's really helpful. And for those of our listeners who are so inclined, there is a wonderful diagram that lays out all these subtypes that you can take a look at. I encourage you to familiarize yourself with these different subtypes. Now it was really interesting to read in your article about some of the older techniques that we used quite some time ago for diagnosing normal pressure hydrocephalus that thankfully we're no longer using, including isotope encephalography and radionuclide cisternography. It certainly made me grateful for how we've come in our diagnostic tools for NPH. What do you think the biggest breakthrough in diagnostic tools that are now clinically available are? Dr. Switzer: You know, definitely the advent of structural imaging was very important for the evaluation of NPH, and specifically the identification of disproportionately enlarged subarachnoid space hydrocephalus, or DESH, in the late nineties has been very helpful for increasing the specificity of diagnosis in NPH. But some of the newer technologies that have become available would be phase-contrast MRI to measure the CSF flow rate through the aqueduct has been very helpful, as well as high spatial resolution T2 imaging to actually

Normal pressure hydrocephalus (NPH) is a clinical syndrome characterized by the triad of gait apraxia, cognitive impairment, and bladder dysfunction in the radiographic context of ventriculomegaly and normal intracranial pressure. Accurate diagnosis requires consideration of clinical and imaging signs, complemented by tests to exclude common mimics. In this episode, Lyell Jones, MD, FAAN speaks with Abhay R. Moghekar, MBBS, author of the article “Clinical Features and Diagnosis of Normal Pressure Hydrocephalus” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Jones is the editor-in-chief of Continuum: Lifelong Learning in Neurology® and is a professor of neurology at Mayo Clinic in Rochester, Minnesota. Dr. Moghekar is an associate professor of neurology at Johns Hopkins University School of Medicine in Baltimore, Maryland. Additional Resources Read the article: Clinical Features and Diagnosis of Normal Pressure Hydrocephalus Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @LyellJ Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum: Lifelong Learning in Neurology. Today I'm interviewing Dr Abhay Moghekar, who recently authored an article on the clinical features and diagnosis of normal pressure hydrocephalus for our first-ever issue of Continuum dedicated to disorders of CSF dynamics. Dr Moghekar is an associate professor of neurology and the research director of the Cerebrospinal Fluid Center at Johns Hopkins University in Baltimore, Maryland. Dr Moghekar, welcome, and thank you for joining us today. Why don't you introduce yourself to our listeners? Dr Moghekar: Thank you, Dr Jones. I'm Abhay Moghekar. I'm a neurologist at Hopkins, and I specialize in seeing patients with CSF disorders, of which normal pressure hydrocephalus happens to be the most common. Dr Jones: And let's get right to it. I think most of our listeners who are neurologists in practice have encountered normal pressure hydrocephalus, or NPH; and it's a challenging disorder for all the reasons that you outline in your really outstanding article. If you were going to think of one single most important message to our listeners about recognizing patients with NPH, what would that be? Dr Moghekar: I think I would say there are two important messages. One is that the triad is not sufficient to make the diagnosis, and the triad is not necessary to make the diagnosis. You know these three elements of the triad: cognitive problems, gait problems, bladder control problems are so common in the elderly that if you pick 10 people out in the community that have this triad, it's unlikely that even one of them has true NPH. On the other hand, you don't need all three elements of the triad to make the diagnosis because the order of symptoms matters. Often patients develop gait dysfunction first, then cognitive dysfunction, and then urinary incontinence. If you wait for all three elements of the triad to be present, it may be too late to offer them any clear benefit. And hence, you know, it's neither sufficient nor necessary to make the diagnosis. Dr Jones: That's a really great point. I think most of our listeners are familiar with the fact that, you know, we're taught these classic triads or pentads or whatever, and they're rarely all present. In a way, it's maybe a useful prompt, but it could be distracting or misleading, even in a way, in terms of recognizing the patient. So what clues do you use, Dr Moghekar, to really think that a patient may have NPH? Dr Moghekar: So, there are two important aspects about gait dysfunction. Say somebody comes in with all three elements of the triad. You want to know two things. Which came first? If gate impairment precedes cognitive impairment, it's still very likely that NPH is in the differential. And of the two, which are more- relatively more affected? So, if somebody has very severe dementia and they have a little bit of gait problems, NPH is not as likely. So, is gait affected earlier than cognitive dysfunction, and is it affected to a more severe degree than cognitive dysfunction? And those two things clue me in to the possibility of NPH. You still obviously need to get imaging to make sure that they have large ventricles. One of the problems with imaging is large ventricles are present in so many different patients. Normal aging causes large ventricles. Obviously, many neurodegenerative disorders because of cerebral atrophy will cause large ventricles. And there's an often-used metric called as the events index, which is the ratio of the bitemporal horns- of the frontal horns of the lateral ventricles compared to the maximum diameter of the skull at that level. And if that ratio is more than 0.3, it's often used as a de facto measure of ventriculomegaly. What we've increasingly realized is that this ratio changes with age. And there's an excellent study that used the ADNI database that looked at how this ratio changes by age and sex. So, in fact, we now know that an 85-year-old woman who has an events index of 0.37 which would be considered ventriculomegaly is actually normal for age and sex. So, we need to start adopting these more modern age- and sex-appropriate age cutoffs of ventriculomegaly so as not to overcall everybody with big ventricles as having possible NPH. Dr Jones: That's very helpful. And I do want to come back to this challenge that we've seen in our field of overdiagnosis and underdiagnosis. But I think most of us are familiar with the concept of how hydrocephalus could cause neurologic deficits. But what's the latest on the mechanism of NPH? Why do some patients get this and others don't? Dr Moghekar: Very good question. I don't think we know for sure. And it for a long time we thought it was a plumbing issue. Right? And that's why shunts work. People thought it was impaired CSF absorption, but multiple studies have shown that not to be true. It's likely a combination of impaired cerebral blood flow, biomechanical factors like compliance, and even congenital factors that play a role in the pathogenesis of NPH. And yes, while putting in shunts likely drains CSF, putting in a shunt also definitely changes the compliance of the brain and affects blood flow to the subcortical regions of the brain. So, there are likely multiple mechanisms by which shunts benefit, and hence it's very likely that there's no single explanation for the pathogenesis of NPH. Dr Jones: We explored this in a recent Continuum issue on dementia. Many patients who have cognitive impairment have co-pathologies, multiple different causes. I was interested to read in your article about the genetic risk profile for NPH. It's not something I'd ever really considered in a disorder that is predominantly seen in older patients. Tell us a little more about those genetic risks. Dr Moghekar: Yeah, everyone is aware of the role genetics plays in congenital hydrocephalus, but until recently we were not aware that certain genetic factors may also be relevant to adult-onset normal pressure hydrocephalus. We've suspected this for a long time because nearly half of our patients who come to us to see us in clinic with NPH have head circumferences that are more than 90th percentile for height. And you know, that clearly indicates that this started shortly at the time after birth or soon afterwards. So, we've suspected for a long time that genetic factors play a role, but for a long time there were not enough large studies or well-conducted studies. But recently studies out of Japan and the US have shown mutations in genes like CF43 and CWH43 are disproportionately increased in patients with NPH. So, we are discovering increasingly that there are genetic factors that underlie even adult onset in patients. There are many more waiting to be discovered. Dr Jones: Really fascinating. And obviously getting more insight into the risk and mechanisms would be helpful in identifying these patients potentially earlier. And another thing that I learned in your article that I thought was really interesting, and maybe you can tell us more about it, is the association between normal pressure hydrocephalus and the observation of cervical spinal stenosis, many of whom require decompression. What's behind that association, do you think? Dr Moghekar: That's a very interesting study that was actually done at your institution, at Mayo Clinic, that showed this association. You know, as we all get older, you know, the incidence of cervical stenosis due to osteoarthritis goes up, but the incidence of significant, clinically significant cervical stenosis in the NPH population was much higher than what we would have expected. Whether this is merely an association in a vulnerable population or is it actually causal is not known and will need further study. Dr Jones: It's interesting to speculate, does that stenosis affect the flow of CSF and somehow predispose to a- again, maybe a partial degree for some patients? Dr Moghekar: Yeah, which goes back to the possible hydrodynamic theory of normal pressure hydrocephalus; you know, if it's obstructing normal CSF flow, you know, are the hydrodynamics affected in the brain that in turn could lead to the development of hydrocephalus. Dr Jones: One of the things I really enjoyed about your article, Abhay, was the very strong clinical focus, right? We can't j

Idiopathic intracranial hypertension (IIH), a condition of increased intracranial pressure (ICP), causes debilitating headaches and, in some, visual loss. The visual defects are often in the periphery and not appreciated by the patient until advanced; therefore, monitoring visual function with serial examinations and visual fields is essential. In this episode, Kait Nevel, MD speaks with John J. Chen, MD, PhD, and Susan P. Mollan, MBChB, PhD, FRCOphth, authors of the article “Treatment and Monitoring of Idiopathic Intracranial Hypertension” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Nevel is a Continuum® Audio interviewer and a neurologist and neuro-oncologist at Indiana University School of Medicine in Indianapolis, Indiana. Dr. Chen is a professor of ophthalmology and neurology at the Mayo Clinic in Rochester, Minnesota. Dr. Mollan is an honorary professor of metabolism and systems science in the department of neuro-ophthalmology at University Hospitals Birmingham in Birmingham, United Kingdom. Additional Resources Read the article: Treatment and Monitoring of Idiopathic Intracranial Hypertension Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @IUneurodocmom Guests: @chenmayo, @DrMollan Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Nevel: Hello, this is Dr Kate Nevel. Today, I'm interviewing Drs John Chen and Susan Mollan about their article on treatment and monitoring of idiopathic intracranial hypertension, which appears in the June 2025 Continuum issue on disorders of CSF dynamics. Drs Chen and Mollan, welcome to the podcast. And please, could you introduce yourselves to the audience? Dr Chen: Hello, everyone. I'm John Chen, one of the neuro-ophthalmologists at the Mayo Clinic. Thanks for having us here. Dr Mollan: Yeah, it's great to be with you here. I'm Susan Mollan. I'm a consultant neuro-ophthalmologist in Birmingham, England. Dr Nevel: Wonderful. So great to have you both here today, and our listeners. To start us off, talking about your article, can you share with us what you think is the most important takeaway from your article for the practicing neurologist out there? Dr Chen: Yeah, so our article talked about the treatment and monitoring of IIH. And I think one takeaway point is, IIH is becoming much more prevalent now that there's this worldwide obesity epidemic with obesity having- essentially being the largest risk factor for IIH other than female. It's really important to monitor vision because vision loss is often peripheral vision loss at first, which the patient may be completely unaware of. And so, it's important to pair up with an ophthalmologist so you can monitor the papilledema of the visual fields and make sure they don't get permanent vision loss. And in the article, we also talk about- there's been changes in the treatment of severe IIH, where traditionally, we used VP shunts; but there's been a trend toward using more venous sinus stenting in addition to the traditional surgeries. Dr Nevel: Great, thank you. I think probably most of our listeners or a lot of neurologists out there have a pretty good understanding of kind of the basics of the IIH. But can you kind of just go over a few key characteristics of IIH, and maybe some things that are less commonly known or things that are maybe just been kind of better understood over the past decade, perhaps? Dr Mollan: Yes, certainly. I think, as Dr Chen said, it's because this condition is becoming more prevalent, people recognize it. I think it's- we like to go back to the diagnostic criteria so that we're making a very accurate diagnosis. So, the patients may come in to the emergency room with, say, papilledema that's been identified elsewhere or crashing headaches. And it's important to go through that sort of diagnostic pathway, taking a blood pressure, taking a full blood count to make sure the patient is anemic, and then moving forward with that confirmation of papilledema into urgent neuroimaging, whether it's CT or MRI, but including venography to exclude a venous sinus thrombosis. And then if you have no structural lesion that's causing the raised ICP, it's moving forward with your lumbar puncture and carefully checking those pressures. But the patients may not only have crashing headache, they often have pulsatile tinnitus and neck pain. I think some of the features that we're now recognizing is the systemic metabolic effects that are unique to IIH. And so, there's an increased risk of cardiometabolic disease that's over and above what is conferred by obesity. Also, our patients have a sort of maternal health burden where they get impaired fertility, gestational diabetes and preeclampsia. And there's also an associated mental health burden, amongst other things. So we're really starting to understand the spectrum of the disease a bit more. Dr Nevel: Yeah, thank you for that. And that really struck me in your article, how important it is to be aware of those things so that we're making sure that we're managing our whole patient and connecting them with the appropriate providers for some of those other issues that may be associated. For the practicing neurologist out there without all the neuro-ophthalmology equipment, if you will, what should our bedside exam focus on to help us get maybe an early but accurate picture of the patient's visual function when we suspect IIH to be at play, perhaps before they can get in with the neuro-ophthalmologist? Dr Chen: Yeah, I think at the bedside you can still check visual acuity and confrontational visual fields, you know, with finger counting. Of course, you have to know that those are, kind of, crude kind of ways of screening. With papilledema, oftentimes the visual acuity is intact. And the confrontational visual fields aren't as sensitive as automated perimetry. Another important thing will be to do your direct ophthalmoscope and look at the amount of papilledema. If it's grade one or two papilledema on the more mild side, it's actually not vision threatening. It's the higher degrees of papilledema that can cause rapid vision loss. And so, if you look in and you see grade one papilledema, obviously you need to do the full workup, the MRI, MRV, lumbar puncture. But in terms of rapidly getting to an ophthalmologist to screen for vision loss, it's not going to be as important because you're not going to have vision loss at that low grade. If you look in and you see this rip-roaring papilledema, grade five papilledema, that patient is going to be at very severe risk of vision loss. So, I think that exam, looking at the optic nerve can be very helpful. And of course, talking to the patient about symptoms; is there decreased vision Is there double vision from a sixth nerve palsy? Are there transient visual obscurations which would indicate at least a higher degree of papilledema? That'd be helpful as well. Dr Nevel: Great, thank you. And when the patient does get in with a neuro-ophthalmologist, you talk in your article and, of course, in clinical practice, how OCT testing is important to monitor in this condition. Can you provide for the listeners the definition of OCT and how it plays a role in monitoring patients with IIH? Dr Mollan: Sure. So, OCT is short for optical coherence tomography imaging, and really the eye has been at the forefront of OCT alone. Our sort of cardiology colleagues are catching up on the imaging of blood vessels. But what it allows us to do is give us really good cross-sectional, anatomical-level changes that we can see both in the retina and also at the optic nerve head. And it gives us some really good measurements. It's not so good at sort of saying, is this definitely papilledema or not? That sort of lower end of disc elevation. But it is very good at ruling out what we call the pseudopapilledema. So, things like drusens or these other little masses we find underneath the optic nerve head. But in terms of monitoring, because we can longitudinally take these images and the reproducibility is pretty good at the optic nerve head, it allows us to see whether there's direct changes: either the papilledema getting worse or the papilledema getting better at the optic nerve head. It also gives us some indication of what's going on in the ganglion cell layer complex. And that can be helpful when we're thinking about sort of looking at structure versus function. So, ophthalmologists in general, we love OCT; and we spend much more time nowadays looking at the OCT than we really do the back of the eye. And it's just become critical for patients with papilledema to be able to be very accurate from visit to visit to see what's changing. Dr Nevel: How do you determine how frequently somebody needs to see the neuro-ophthalmologist with IIH and how often they need that OCT evaluation? Dr Chen: Once the diagnosis of IIH is made, how often they need to be seen and how frequent they need to be seen depends on the degree of papilledema. And again, OCT is really nice. You can quantify it and then different providers can actually use the same OCT numbers, which is super helpful. But again, if it's grade three papilledema or higher, or article thickness of 200 or higher, I tend to follow them a little bit more closely, trying to treat them more aggressively. Try to get the papilledema down into a safer zone. If it's grade one or two papilledema, we see the

Idiopathic intracranial hypertension (IIH) is characterized by symptoms and signs of unexplained elevated intracranial pressure (ICP) in an alert and awake patient. The condition has potentially devastating effects on vision, headache burden, increased cardiovascular disease risk, sleep disturbance, and depression.  In this episode, Teshamae Monteith, MD, FAAN speaks with Aileen A. Antonio, MD, FAAN, author of the article “Clinical Features and Diagnosis of Idiopathic Intracranial Hypertension” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Monteith is the associate editor of Continuum® Audio and an associate professor of clinical neurology at the University of Miami Miller School of Medicine in Miami, Florida. Dr. Antonio is an associate program director of the Hauenstein Neurosciences Residency Program at Trinity Health Grand Rapids and an assistant clinical professor at the Michigan State University College of Osteopathic Medicine in Lansang, Michigan. Additional Resources Read the article: Clinical Features and Diagnosis of Idiopathic Intracranial Hypertension Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Host: @headacheMD Guest: @aiee_antonio Full episode transcript available here Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Monteith: Hi, this is Dr Teshamae Monteith. Today I'm interviewing Dr Aileen Antonio about her article on clinical features and diagnosis of idiopathic intracranial hypertension, which appears in the June 2025 Continuum issue on disorders of CSF dynamics.  Hi, how are you? Dr Antonio: Hi, good afternoon. Dr Monteith: Thank you for being on the podcast. Dr Antonio: Thank you for inviting me, and it's such an honor to write for the Continuum. Dr Monteith: So why don't you start off with introducing yourself? Dr Antonio: So as mentioned, I'm Aileen Antonio. I am a neuro-ophthalmologist, dually trained in both ophthalmology and neurology. I'm practicing in Grand Rapids, Michigan Trinity Health, and I'm also the associate program director for our neurology residency program. Dr Monteith: So, it sounds like the residents get a lot of neuro-ophthalmology by chance in your curriculum. Dr Antonio: For sure. They do get fed that a lot. Dr Monteith: So why don't you tell me what the objective of your article was? Dr Antonio: Yes. So idiopathic intracranial hypertension, or IIH, is a condition where there's increased intracranial pressure, but without an obvious cause. And with this article, we want our readers---and our listeners right now---to recognize that the typical symptoms and learning about the IIH diagnostic criteria are key to avoiding errors, overdiagnosis, or sometimes even misdiagnosis or underdiagnosis. Thus, we help make the most of our healthcare resources. Early diagnosis and management are crucial to prevent disability from intractable headaches or even vision loss, and it's also important to know when to refer the patients to the appropriate specialists early on. Dr Monteith: So, it sounds like your central points are really getting that diagnosis early and managing the patients and knowing how to triage patients to reduce morbidity and complications. Is that correct? Dr Antonio: That is correct and very succinct, yes. Dr Monteith: And so, are there any more recent advances in the diagnosis of IIH? Dr Antonio: Yes. And one of the tools that we've been using is what we call the optical coherence tomography. A lot of people, neurologists, physicians, PCP, ER doctors; how many among those physicians are well-versed in doing an eye exam, looking at the optic disc? And this is a great tool because it is noninvasive, it is high resolution imaging technique that allows us to look at the optic nerve without even dilating the eye. And we can measure that retinal nerve fiber layer, or RNFL; and that helps us quantify the swelling that is visible or inherent in that optic nerve. And we can even follow that and monitor that over time. So, this gives us another way of looking at their vision and getting that insight as to how healthy is their vision still, along with the other formal visual tests that we do, including perimetry or visual field testing. And then all of these help in catching potentially early changes, early worsening, that may happen; and then we can intervene more easily. Dr Monteith: Great. So, it sounds like there's a lot of benefits to this newer technology for our patients. Dr Antonio: That is correct. Dr Monteith: So, I read in the article about the increased incidence of IIH, and I have to say that I completely agree with you because I'm seeing so much of it in my clinic, even as a headache specialist. And I had a talk with a colleague who said that the incidence of SIH and IIH are similar. And I was like, there's no way. Because I see, I can see several people with IIH just in one day. That's not uncommon. So, tell me what your thoughts are on the incidence, the rising incidence of IIH; and we understand that it's the condition associated with obesity, but it sounds like you have some other underlying drivers of this problem. Dr Antonio: Yes, that is correct. So, as you mentioned, IIH tends to affect women of childbearing age with obesity. And it's interesting because as you've seen that trend, we see more of these IIH cases recently, which seem to correlate with that rising rate of obesity. And the other thing, too, is that this trend can readily add to the burden of managing IIH, because not only are we dealing with the headaches or the potential loss of vision, but also it adds to the burden of healthcare costs because of the other potential comorbidities that may come with it, like cardiovascular risk factors, PCOS, and sleep apnea. Dr Monteith: So why don't we just talk about the diagnosis of IIH? Dr Antonio: IIH, idiopathic intracranial hypertension, is also called pseudotumor cerebri.  It’s essentially a condition where a person experiences increased intracranial pressure, but without any obvious cause. And the tricky part is that the patients, they're usually fully awake and alert. So, there's no obvious tumor, brain tumor or injury that causes the increased ICP. It's really, really important to rule out other conditions that might cause these similar symptoms; again, like brain tumors or even the cerebral venous sinus thrombosis. Many patients will have headaches or visual disturbances like transient visual obscurations---we call them TVOs---or double vision or diplopia. The diplopia is usually related to a sixth nerve palsy or an abducens palsy. Some may also experience some back pain or what we call pulsatile tinnitus, which is that pulse synchronous ringing in their ears. The biggest sign that we see in the clinic would be that papilledema; and papilledema is a term that we only use, specifically use, for those optic nerve edema changes that is only associated with increased intracranial pressure. So, performing of endoscopy and good eye exam is crucial in these patients. We usually use the modified Dandy criteria to diagnose IIH. And again, I cannot emphasize too much that it's really important to rule out other secondary causes to that increased intracranial pressure. So, after that thorough neurologic and eye evaluation with neuroimaging, we do a lumbar puncture to measure the opening pressure and to analyze the cerebrospinal fluid. Dr Monteith: One thing I learned from your article, really just kind of seeing all of the symptoms that you mentioned, the radicular pain, but also- and I think I've seen some papers on this, the cognitive dysfunction associated with IIH. So, it's a broader symptom complex I think than people realize. Dr Antonio: That is correct. Dr Monteith: So, you mentioned TVOs. Tell me, you know, if I was a patient, how would you try and elicit that from me? Dr Antonio: So, I would usually just ask the patient, while you're sitting down just watching TV---some of my patients are even driving as this happens---they would suddenly have these episodes of blacking out of vision, graying out of vision, vision loss, or blurred vision that would just happen, from seconds to less than a minute, usually. And they can happen in one eye or the other eye or both eyes, and even multiple times a day. I had a patient, it was happening 50 times a day for her. It's important to note that there is no pain associated with it most of the time. The other thing too is that it's different from the aura that patients with migraines would have, because those auras are usually scintillating and would have what we call the positive phenomena: the flashing lights, the iridescence, and even the fortification that they see in their vision. So definitely TVOs are not the migraine auras. Sometimes the TVOs can also be triggered by sudden changes in head positions or even a change in posture, like standing up quickly. The difference, though, between that and, like, the graying out of vision or the tunneling vision associated with orthostatic hypotension, is that the orthostatic hypotension would also have that feeling of lightheadedness and dizziness that would come with it. Dr Monteith: Great. So, if someone feels lightheaded, less likely to be a TVO if they're bending down and they have that grain of vision. Dr Antonio: That is correct. Dr Monteith: Definitely see patients like that in clinic. And if they have fluoride IIH, I'm like, I'll call it a TVO; if they don't, I’m like, it's pr

Recently, sophisticated myelographic techniques to precisely subtype and localize CSF leaks have been developed and refined. These techniques improve the detection of various types of CSF leaks thereby enabling targeted therapies. In this episode, Katie Grouse, MD, FAAN, speaks with Ajay A. Madhavan, MD, author of the article “Radiographic Evaluation of Spontaneous Intracranial Hypotension” in the Continuum® June 2025 Disorders of CSF Dynamics issue. Dr. Grouse is a Continuum® Audio interviewer and a clinical assistant professor at the University of California San Francisco in San Francisco, California. Dr. Madhavan is assistant professor of radiology at the Mayo Clinic in Rochester, Minnesota. Additional Resources Read the article: Radiographic Evaluation of Spontaneous Intracranial Hypotension Subscribe to Continuum®: shop.lww.com/Continuum Earn CME (available only to AAN members): continpub.com/AudioCME Continuum® Aloud (verbatim audio-book style recordings of articles available only to Continuum® subscribers): continpub.com/Aloud More about the American Academy of Neurology: aan.com Social Media facebook.com/continuumcme @ContinuumAAN Full episode transcript available here Dr Jones:  This is Dr Lyell Jones, Editor-in-Chief of Continuum. Thank you for listening to Continuum Audio. Be sure to visit the links in the episode notes for information about earning CME, subscribing to the journal, and exclusive access to interviews not featured on the podcast. Dr Grouse:  This is Dr Katie Grouse. Today I'm interviewing Dr Ajay Madhavan about his article on Radiographic Evaluation of Spontaneous Intracranial Hypotension, which he wrote with Dr Levi Chazen. This article appears in the June 2025 Continuum issue on disorders of CSF dynamics. Welcome to the podcast, and please introduce yourself to our audience. Dr Madhavan:  Hi, thanks a lot, Katie. Yeah, so I’m Ajay Madhaven. I'm a neuroradiologist at the Mayo Clinic in Rochester, Minnesota. I did all my training here, so, I've been here for a long time. And I have a lot of interest in spinal CSF leaks, and I do a lot of that work. And so I'm really excited to be talking about this article with you. Dr Grouse:  I'm really excited too. And in fact, it's such a pleasure to have you here talking today on this topic. I know a lot's changed in this field, and I'm sure many of our listeners are really interested in learning about the developments and imaging techniques to improve detection and treatment of CSF leaks, especially since maybe we've learned about this in training. I want to start by asking you what you think is the most important takeaway from your article. Dr Madhavan:  Yeah, that's a great question. I think---and you kind of already alluded to it---I think the main thing is, I hope people recognize that this field has really changed a lot in the last five to ten years, through a lot of multi-institutional collaboration and also collaboration between different specialties. We've learned a lot about different types of spinal CSF leaks, how we can recognize the disease, particularly the types of myelography that we need to be using to accurately localize and treat these leaks. Those are the things that have really evolved in the last five to ten years, and they've really helped us improve these patients’ lives. Dr Grouse:  Can you remind us of the different common types of spinal leaks that can cause spontaneous intracranial hypotension? Dr Madhavan:  Yeah, so there are a number of different spinal CSF leaks, types, and I would say the three most common ones that really most people should try to be aware of and cognizant of are: first, ventral dural tears. So those are, like, just physical holes in the dura. And they're usually caused by little bone spurs that come from the vertebral columns. So, they're often patients who have some degenerative changes in their spine. And those are really very common. Another type of spinal CSF leak that we commonly see is a lateral dural tear. So that's like the same thing in a slightly different location. So instead of being in the front, it's off to the side of the dura laterally. And so, it's also just a hole in the dura. And then the third and most recently discovered type of spinal CSF leak is a CSF-venous fistula. So those are direct connections between the subarachnoid space and little paraspinal vein. And it took us a long time to even realize that this was a real pathology. But now that it's been recognized, we've found that this is actually quite common. So those three types of leaks are probably the three most common that we see. And there's certainly others out there, but I would say over 90% of them fall into one of those three categories. Dr Grouse:  That's a great review, thank you. Just as another quick review, as we talk more about this topic, can you remind us of some of the most common or typical brain imaging findings that you'll see in cases of spontaneous intracranial hypotension? Dr Madhavan:  Yeah, absolutely. So, when you do a brain MRI in a patient who has spontaneous intracranial hypotension, you will usually, though not always, see typical brain MRI abnormalities. And I kind of think of those as falling into three different categories. So, the first one I think of is dural enhancement or thickening. So that's enlargement or engorgement of the dura, the pachymeninges, and enhancement on postgadolinium imaging. So, that's kind of the first category. The second is that, when you lose spinal fluid volume, other things often expand to take up the space. So, for example, you can get distension or enlargement of the dural venous sinuses, and sometimes you can also get subdural food collections or hematomas. They can arise spontaneously. And I kind of think of those as, you know, you, you've lost the cerebrospinal fluid volume and something else is kind of filling up the space. And then the third category is called brain sagging. And that's a constellation of findings where the posterior fossa structures and the pituitary gland in the cell have become abnormal because you've lost the fluid that normally cushions those structures and causes them to float up. For example, the brain stem will sag down, the distance between the mammillary body and the ponds may become reduced. The suprasellar cistern space may be reduced such that the optic chiasm becomes very close to the pituitary gland, and the prepontine cistern may also become reduced in size. And there are various measurements that can be used to determine whether something is subtly abnormal. But just generally speaking, those are really the three categories of brain MRI abnormalities you'll see. Dr Grouse:  That was a great review. And of course, I think in many times when we are thinking about or suspecting this diagnosis, we may be lucky to find those imaging findings to reinforce a diagnosis. Because as it turns out, after reading your article, I was really surprised to find out that in as many as 19% of cases we actually see normal brain imaging, which really was a surprise to me, I have to say. And I think that this really encompasses why spontaneous intercranial hypotension is such a difficult diagnosis to make. I think a lot of us struggle with how far to take the workup when, you know, spontaneous intercranial hypotension is clinically suspected, but multiple imaging studies are normal. Do you have any guidance on how to approach these more difficult cases? Dr Madhavan:  So, that's a really good question. And you know, it's- as you can imagine, that's a topic that comes up in most meetings where people discuss this, and it's been a continued challenge. And so, like you said, about 19 or 20% of patients who have this disease can have a, a normal brain MRI. And we've tried to do some work to figure out why that is and how we can identify patients who still have the disease. And I can just provide, I guess, some tips that have helped me in my clinical practice. One thing is, if I ever see a patient with a normal brain MRI where this disease is clinically suspected---for example, maybe they have orthostatic headaches or other very typical symptoms and we don't know why, but their brain MRI is normal---the first thing I do is I try to look back at their old imaging. So many times, these patients who present to us at Mayo, who, when we do their MRI scan here, their brain MRI looks normal… if you really look back at imaging that they've had done elsewhere---maybe even two to three years prior---at the time their symptoms started, they actually had some abnormalities. So, I might see that a patient, two years ago, had dural enhancement that spontaneously resolved; but now they still have symptoms of SIH and they may still have a CSF leak that we can find and treat, but their brain MRI has, for whatever reason, normalized. So, I always start by looking back at old imaging, and I found that to be very helpful. The other thing is, if you see a patient with a normal brain MRI, it's also important to look at their spine MRI because that can provide clues that might suggest that they could still have a spinal CSF leak. And the two things I look for on the spine MRI: one, if there's any extradural CSF. So, spinal fluid outside of where it's supposed to be within the confines of the subarachnoid space. And you know, really, if you see extradural CSF, you know they probably have a spinal fluid leak somewhere. Even if their brain MRI is normal, that just gives you the information that there is a dural tear probably somewhere. And so, in those patients we’ll definitely still proceed to myelography or other testing, even if they have a normal brain MRI. And then the last thing I look for is whether or not they have prominent meningeal diverticula. Patients with CSF venous fistulas almost always have one or more prominent diverticula on their spine along the nerve root sleeves. And that's probably because most of these fistulas come from ne