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1. Kato S, Maesawa S, Bagarinao E, et al. Magnetic resonance–guided focused ultrasound thalamotomy restored distinctive resting-state networks in patients with essential tremor. J Neurosurg. 2023;138(2):306-317. doi:10.3171/2022.5.JNS22411

Magnetic resonance–guided focused ultrasound (MRgFUS) thalamotomy ameliorates symptoms in patients with essential tremor (ET). How this treatment affects canonical brain networks has not been elucidated. The purpose of this study was to clarify changes of brain networks after MRgFUS thalamotomy in essential tremor patients by analyzing resting-state networks (RSNs). Fifteen patients with ET were included in this study. Left MRgFUS thalamotomy was performed in all cases, and MR images, including resting-state functional MRI (rsfMRI), were taken before and after surgery. MR images of 15 age- and sex-matched healthy controls (HCs) were also used for analysis. Using rsfMRI data, canonical RSNs were extracted by performing dual regression analysis, and the functional connectivity (FC) within respective networks was compared among pre-MRgFUS patients, post-MRgFUS patients, and healthy controls. The severity of tremor was evaluated using the Clinical Rating Scale for Tremor (CRST) score pre- and postoperatively, and its correlation with RSNs was examined. Preoperatively, essential tremor patients showed a significant decrease in functional connectivity in the sensorimotor network (SMN), primary visual network (VN), and visuospatial network (VSN) compared with HCs. The decrease in functional connectivity in the sensorimotor network correlated with the severity of tremor. After MRgFUS thalamotomy, essential tremor patients still exhibited a significant decrease in functional connectivity in a small area of the sensorimotor network, but they exhibited an increase in the cerebellar network (CN). In comparison between pre- and post- MRgFUS patients, the functional connectivity in the sensorimotor network and the visuospatial network significantly increased after treatment.

The sensorimotor network and cerebellar network, which are considered to be associated with the cerebello-thalamo-cortical loop, exhibited increased connectivity after MRgFUS thalamotomy. In addition, the FC of the visual network, which declined in essential tremor patients compared with HCs, tended to normalize postoperatively. This demonstrates the possibility of using RSN changes as biomarkers for successful treatment.

5 figures, 4 tables

2. Jamshidi AM, Soldozy S, Levi AD. Percutaneous Direct Pars Repair in Young Athletes. Neurosurgery. 2023;92(2):263-270. doi:10.1227/neu.0000000000002210

Lumbar pars defects are common in adolescent athletes and are often due to recurrent axial loading and traumatic stressors. The objective of the study was to present an updated case series of young athletes who underwent percutaneous direct pars repair after failure of conservative management.

The literature suggests that conservative management should be used for at least 6 months before surgical intervention. In this series of 21 patients, all patients failed conservative management after a mean nonoperative treatment duration of 20.5 ± 9.3 months. These cases were specifically referred from outside institutions for a minimally invasive surgical option after failure of conservative treatment.

A single-center, nonrandomized, retrospective observation study of athletes who were referred for minimally invasive direct pars repair after failure of at least 6 months of conservative management was performed. A total of 21 patients were included (mean age 17.47 years, range 14-25 years), 6 of whom were female (29%). All patients presented with bilateral pars fractures, with L5 being the most frequent level involved (n = 13). The average follow-up time was 31.52 months.

The visual analog scale score for back pain was significantly reduced from 7.62 preoperatively to 0.28 at the final postoperative examination (P < .01). Fusion was noted in 20 of the 21 patients on final follow-up (95%).

They conclude that percutaneous direct pars repair is a safe and effective means in treating young adolescents who have failed conservative management. The advantages included minimized muscle and soft tissue dissection, reduced blood loss, and early mobilization and recovery. In young athletes who desire return to high-level physical activity, this surgical technique is of particular benefit and should be considered in this patient population.

Despite conservative measures, some patients continue to experience pain. Surgical repair of the pars defect can be offered for this small minority of patients who qualify. In this cohort, despite the broad referral area and adherence to minimum conservative treatment periods combined with the 12-year recruitment period, only 21 surgical cases were selected. These facts highlight that the indication for surgery is relatively rare and that most patients respond well to conservative treatment. For those who underwent surgery, a similar return-to-play rate was seen when compared with those patients who were managed conservatively (90.3%vs 92.2%, respectively).

4 figures, 2 tables, with MR, CT, intraop fluoro

3. Schaff LR, Mellinghoff IK. Glioblastoma and Other Primary Brain Malignancies in Adults. (a review) JAMA. 2023;329(7):574. doi:10.1001/jama.2023.0023

Approximately 50% of malignant brain tumors are glioblastomas, and 30% are diffusely infiltrating lower-grade gliomas. Other malignant brain tumors include primary central nervous system (CNS) lymphoma (7%) and malignant forms of ependymomas (3%) and meningiomas (2%). Symptoms of malignant brain tumors include headache (50%), seizures (20%-50%), neurocognitive impairment (30%-40%), and focal neurologic deficits (10%-40%). MRI before and after a gadolinium-based contrast agent is the preferred imaging modality for evaluating brain tumors. Diagnosis requires tumor biopsy with consideration of histopathological and molecular characteristics. Treatment varies by tumor type and often includes a combination of surgery, chemotherapy, and radiation.

For patients with glioblastoma, the combination of temozolomide with radiotherapy improved survival when compared with radiotherapy alone (2-year survival, 27.2% vs 10.9%; 5-year survival, 9.8% vs 1.9%). In patients with anaplastic oligodendroglial tumors with 1p/19q codeletion, probable 20-year overall survival following radiotherapy without vs with the combination of procarbazine, lomustine, and vincristine was 13.6% vs 37.1% (80 patients) in the EORTC 26951 trial and 14.9% vs 37% in the RTOG 9402 trial (125 patients). Treatment of primary CNS lymphoma includes high-dose methotrexate-containing regimens, followed by consolidation therapy with myeloablative chemotherapy and autologous stem cell rescue, nonmyeloablative chemotherapy regimens, or whole brain radiation.

3 figures and 2 tables, including a schematic of Integration of Histological Features and Molecular Alterations in the Revised WHO Classification of Tumors of the Central Nervous System

4. Mantovani A, Garlanda C. Humoral Innate Immunity and Acute-Phase Proteins. N Engl J Med. 2023;388(5):439-452. doi:10.1056/NEJMra2206346

Systemic manifestations of inflammation include fever, alterations in leukocyte counts, cardiovascular reactions, endocrine responses, and reorientation of metabolism in association with increased production of a diverse set of molecules referred to as acute-phase proteins. The prototypic acute-phase protein, C-reactive protein, was originally described as a molecule that was present in the circulation of patients with infections and that was capable of recognizing the C-type polysaccharides of Streptococcus pneumoniae. The appearance of increased levels of acute phase proteins in blood and other body fluids is part of a more complex response to local inflammation or to systemic inflammation (e.g., sepsis) that has been referred to as the acute-phase response, which is characterized by decreased production of albumin by hepatocytes, reorientation of iron metabolism, and hormonal changes.

Innate immunity is a first line of resistance against microbial pathogens and is involved in the activation of adaptive immune responses, as well as in tissue repair. Innate immunity is made up of a cellular arm and a humoral arm. The molecular strategies used by the cellular arm to sense microbial moieties and tissue damage involve cell-associated pattern-recognition molecules located in different cellular compartments (plasma membrane, endosomes, and cytoplasm) and belonging to different molecular families, including toll-like receptors (TLRs), nucleotide- binding oligomerization domain (NOD)–like and retinoic acid–inducible gene I (RIG-I)– like receptors.

The activation of these receptors leads to the expression of cytokines (including interferons and chemokines), adhesion molecules, and antimicrobial effectors or to the scavenging of microbes through phagocytosis. The humoral arm of the innate immune system is made up of different classes of molecules, such as pentraxins, collectins, and ficolins, which functionally act as ancestors of antibodies (anteantibodies) by initiating complement activation, opsonizing microbes and damaged cells, agglutinating or neutralizing microbes, and regulating inflammation.

4 figures, 1 table

5. Hornung AL, Barajas JN, Rudisill SS, et al. Prediction of lumbar disc herniation resorption in symptomatic patients: a prospective, multi-imaging and clinical phenotype study. S