Faculty Bibliography

Large hemispheric infarcts occur in up to 10% of all ischemic strokes and can cause devastating disability. Significant research and clinical efforts have been made in hopes of mitigating the morbidity and mortality of this disease. Areas of interest include identifying predictors of malignant edema, optimizing medical and surgical techniques, selecting the patient population that would benefit most from decompressive hemicraniectomy, and studying the impact on quality of life of those who survive. Decompressive surgery can be a life-saving measure, and here we discuss the most up-to-date literature and provide a review on the surgical management of large hemispheric ischemic strokes.

Cerebrovascular disease (stroke) is one of the ten leading causes of death in children and adolescents. Multiple etiologies, from arteriopathies to prothrombic states, can cause stroke in youth. In adult stroke, hypertension has been shown to be the single most important modifiable risk factor. Although hypertension has not been strongly identified as a risk factor in childhood stroke to date, there is preliminary evidence that suggests that hypertension may also be associated with stroke in children. In this review, we summarize the literature that may link hypertension to stroke in the young. We have identified a series of barriers and limitations in the fields of pediatric hypertension and pediatric neurology that might explain why hypertension has been overlooked in childhood stroke. We suggest that hypertension may be a relevant risk factor that, alone or in combination with other multiple factors, contributes to the development of stroke in children. Currently, there are no consensus guidelines for the management of post-stroke hypertension in children. Thus, we recommend that blood pressure be assessed carefully in every child presenting with acute stroke in order to better understand the effects of hypertension in the development and the outcome of childhood stroke. We suggest a treatment algorithm to help practitioners manage hypertension after a stroke.

Fatal familial insomnia (FFI) is a rare inherited prion disease characterized by sleep, autonomic and motor disturbances. Neuro-ophthalmological abnormalities have been reported at the onset of disease, though not further characterized. We analyzed video recordings of eye movements of six FFI patients from three unrelated kindreds, seen within six months from the onset of illness. Excessive saccadic intrusions was the most prominent finding. In patients with severe insomnia, striking saccadic intrusions are an early diagnostic clue for FFI. The fact that the thalamus is the first structure affected in FFI also suggests its role in the control of steady fixation. This article is protected by copyright. All rights reserved.

Direct electrical stimulation can modulate the activity of brain networks for the treatment of several neurological and neuropsychiatric disorders and for restoring lost function. However, precise neuromodulation in an individual requires the accurate modelling and prediction of the effects of stimulation on the activity of their large-scale brain networks. Here, we report the development of dynamic input-output models that predict multiregional dynamics of brain networks in response to temporally varying patterns of ongoing microstimulation. In experiments with two awake rhesus macaques, we show that the activities of brain networks are modulated by changes in both stimulation amplitude and frequency, that they exhibit damping and oscillatory response dynamics, and that variabilities in prediction accuracy and in estimated response strength across brain regions can be explained by an at-rest functional connectivity measure computed without stimulation. Input-output models of brain dynamics may enable precise neuromodulation for the treatment of disease and facilitate the investigation of the functional organization of large-scale brain networks.

OBJECTIVE:Many people with new-onset focal epilepsy initially seek evaluation in emergency departments (EDs), and treatment decisions in EDs can influence likelihood of seizure recurrence. Using data collected for the Human Epilepsy Project (HEP), we assessed the effect of clinical seizure characteristics on ED clinical management. METHODS:There were 447 participants with new-onset focal epilepsy seen within four months of treatment initiation who were eligible and enrolled in HEP. Seizure calendars and medical records were collected. Based on clinical descriptions, seizures were categorized by semiology according to International League Against Epilepsy (ILAE) classifications as either focal non-motor or focal motor seizures. RESULTS:Overall, 279/447(62%) of participants had presented to an ED prior to or at time of epilepsy diagnosis. 132 /246 (53%) with initial non-motor seizures presented to an ED. Of these, 8 (6%) presented with a first-lifetime non-motor seizure. The other 124 (94%) presented after multiple seizures: 7 (5%) with multiple non-motor seizures, and 117 (89%) with a first-lifetime motor seizure after having prior non-motor seizures. 147/ 201 (73%) of participants with initial motor seizures presented to an ED. Of these, 134 (92%) presented with a first-lifetime motor seizure, and 13 (9%) with multiple motor seizures. There was no difference in the likelihood of anti-seizure medication (ASM) initiation between participants who had multiple prior non-motor seizures followed by a motor seizure (thereby fulfilling the criterion for an epilepsy diagnosis), vs those presenting with a single lifetime motor seizure (39% vs 43%). There was no difference in recognition of seizures as the presenting complaint (85% vs 87%), or whether the participant was admitted or referred to a neurologist (87% vs 79%). CONCLUSIONS:This study contributes to evidence of under-recognition of non-motor focal seizure semiologies in ED settings, which can support large-scale interventions aimed at improving recognition, specialist consultation, and treatment in ED settings.

PURPOSE/OBJECTIVE:The unified multiple system atrophy (MSA) rating scale (UMSARS) was developed almost 20 years ago as a clinical rating scale to capture multiple aspects of the disease. With its widespread use, the shortcomings of the UMSARS as a clinical outcome assessment (COA) have become increasingly apparent. We here summarize the shortcomings of the scale, confirm some of its limitations with data from the Natural History Study of the Synucleinopathies (NHSS), and suggest a framework to develop and validate an improved COA to be used in future clinical trials of disease-modifying drugs in patients with MSA. METHODS:Expert consensus assessment of the limitations of the UMSARS and recommendations for the development and validation of a novel COA for MSA. We used UMSARS data from the ongoing NHSS (ClinicalTrials.gov: NCT01799915) to showcase some of these limitations. RESULTS:The UMSARS in general, and specific items in particular, have limitations to detect change resulting in a ceiling effect. Some items have specific limitations including unclear anchoring descriptions, lack of correlation with disease severity, susceptibility to improve with symptomatic therapies (e.g., orthostatic hypotension, constipation, and bladder dysfunction), and redundancy, among others. CONCLUSIONS:Because of the limitations of the UMSARS, developing and validating an improved COA is a priority. The time is right for academic MSA clinicians together with industry, professional societies, and patient advocacy groups to develop and validate a new COA.

Introduction: Mucopolysaccharidosis VII (MPS VII) is an ultra-rare, autosomal recessive, debilitating, progressive lysosomal storage disease caused by beta-glucuronidase (GUS) enzyme deficiency. Vestronidase alfa (recombinant human GUS) enzyme replacement therapy is approved in the United States, Europe, and Latin America for the treatment of MPS VII.
Method(s): The disease monitoring program (DMP) is an ongoing, multicenter observational study collecting standardized real-world data from patients with MPS VII (N~35) treated with vestronidase alfa or with any other management approach. Investigational sites are centers with expertise in the treatment of mucopolysaccharidosis. Data will be collected for up to 10 years and include demographics, clinical history, clinical characteristics, cognition, mobility, skeletal disease, pulmonary function, patient/caregiver-reported healthrelated quality of life, and long-term vestronidase alfa safety and effectiveness. Data are monitored and recorded in compliance with Good Clinical Practice (GCP) guidelines. Annual individual patient reports will be provided to respective patients and caregivers.
Result(s): As of May 31, 2020, sixteen patients are enrolled: 11 prescribed vestronidase alfa and 5 not treated with vestronidase alfa. Median (min, max) age at MPS VII diagnosis was 4.1 (0.1, 12.0) years. Six patients (38%) had a history of non-immune hydrops fetalis. Four patients who reached one year of treatment in the DMP had a mean (SD) decrease of 1.18 (0.35) g GAG/g creatinine in dermatan sulfate uGAG excretion from the parent (clinical) study baseline (88% reduction). Three serious adverse events (SAEs) unrelated to vestronidase alfa occurred: recurrent cervical spinal stenosis, corneal opacity, and parainfluenza virus infection. One SAE, intermittent hypotension, was assessed as an infusion-associated reaction to vestronidase alfa. All SAEs were consistent with the known safety profile of vestronidase alfa. No deaths were reported.
Conclusion(s): Reductions in uGAG demonstrate ongoing effectiveness of vestronidase alfa at Year 1 of the DMP. No newsafety concernswere identified, and all patients continue on-study. Enrollment is ongoing.
Copyright 2021 Elsevier Inc. All rights reserved

Objective: We sought to identify novel genes and to establish the contribution of known genes in a large cohort of patients with nonsyndromic sporadic polymicrogyria and epilepsy.
Method(s): We enrolled participants with polymicrogyria and their parents through the Epilepsy Phenome/Genome Project. We performed phenotyping and whole exome sequencing (WES), trio analysis, and gene-level collapsing analysis to identify de novo or inherited variants, including germline or mosaic (postzygotic) single nucleotide variants, small insertion-deletion (indel) variants, and copy number variants present in leukocyte-derived DNA.
Result(s): Across the cohort of 86 individuals with polymicrogyria and epilepsy, we identified seven with pathogenic or likely pathogenic variants in PIK3R2, including four germline and three mosaic variants. PIK3R2 was the only gene harboring more than expected de novo variants across the entire cohort, and likewise the only gene that passed the genome-wide threshold of significance in the gene-level rare variant collapsing analysis. Consistent with previous reports, the PIK3R2 phenotype consisted of bilateral polymicrogyria concentrated in the perisylvian region with macrocephaly. Beyond PIK3R2, we also identified one case each with likely causal de novo variants in CCND2 and DYNC1H1 and biallelic variants in WDR62, all genes previously associated with polymicrogyria. Candidate genetic explanations in this cohort included single nucleotide de novo variants in other epilepsy-associated and neurodevelopmental disease-associated genes (SCN2A in two individuals, GRIA3, CACNA1C) and a 597-kb deletion at 15q25, a neurodevelopmental disease susceptibility locus.
Significance: This study confirms germline and postzygotically acquired de novo variants in PIK3R2 as an important cause of bilateral perisylvian polymicrogyria, notably with macrocephaly. In total, trio-based WES identified a genetic diagnosis in 12% and a candidate diagnosis in 6% of our polymicrogyria cohort. Our results suggest possible roles for SCN2A, GRIA3, CACNA1C, and 15q25 deletion in polymicrogyria, each already associated with epilepsy or other neurodevelopmental conditions without brain malformations. The role of these genes in polymicrogyria will be further understood as more patients with polymicrogyria undergo genetic evaluation.
Copyright