Faculty Bibliography

OBJECTIVE:Carotid artery plaque burden, indirectly measured by the degree of stenosis, quantifies future embolic risk. In natural history studies, patients with moderate degrees of stenosis have a lower stroke risk than those with severe stenosis. However, patients with symptomatic carotid stenosis who have experienced TIA or stroke are found to have both moderate and severe degrees of stenosis. We sought to examine the association carotid artery stenosis severity with outcomes in symptomatic patients undergoing carotid interventions including carotid endarterectomy (CEA), transfemoral carotid artery stenting (CAS) and transcervical carotid artery revascularization (TCAR). METHODS:The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing CAS, CEA and TCAR between 2003 and 2020. Patients were stratified into two groups based on the severity of stenosis - non-severe (0 - 69%) and severe (≥ 70%). Primary endpoints were periprocedural neurologic events (strokes and transient ischemic attacks (TIAs)). Secondary endpoints were periprocedural death, myocardial infarction (MI) and composite outcomes of stroke/death and stroke/death/MI per reporting standards for carotid interventions. RESULTS:Of 29,614 symptomatic patients included in the analysis, 5,296 (17.9%) patients underwent TCAR, 7,844 (26.5%) underwent CAS, and 16,474 (55.6%) underwent CEA for symptomatic carotid artery stenosis. In the CEA cohort, the neurologic event rate was similarly significantly lower in patients with severe stenosis when compared to those with non-severe stenosis (2.6% vs. 3.2%, P=.024). In the TCAR cohort, the periprocedural neurologic even rate was lower in patients with severe stenosis when compared to those with non-severe stenosis (3% vs. 4.3%, P=.033). There was no similar difference noted in the CAS cohort, with periprocedural neurologic event rates of 3.8% in the severe group versus 3.5% in the non-severe group (P=.518). On multivariable analysis, severe stenosis was associated with significantly decreased odds of post procedural neurologic events in patients undergoing CEA (odds ratio [OR] 0.75, 95% confidence interval [CI], 0.6 - 0.92; P=.007) and TCAR (OR .83; CI, .69 - 0.99; P=.039), but not CAS. CONCLUSION/CONCLUSIONS:Severe carotid stenosis as opposed to more moderate degrees of stenosis was associated with decreased rates of periprocedural stroke and TIAs in symptomatic patients undergoing TCAR and CEA, but not CAS. The finding of increased rates of periprocedural neurologic events in symptomatic patients with lesser degrees of stenosis undergoing TCAR and CEA warrants further evaluation with a particular focus on plaque morphology and brain physiology, and their inherent risks with carotid revascularization procedures.

Clinical studies of rescue medications for seizure clusters are limited and designed to satisfy regulatory requirements, which may not fully consider the needs of the diverse patient population that experiences seizure clusters or utilize rescue medication. The purpose of this narrative review is to examine factors that contribute to, or may influence the quality of, seizure cluster research with a goal of improving clinical practice. We address five areas of unmet needs and provide advice of how they could enhance future trials of seizure cluster treatments. The topics addressed in this manuscript are: 1) unaddressed endpoints to pursue in future studies, 2) roles for devices to enhance rescue medication clinical development programs, 3) tools to study seizure cluster prediction and prevention, 4) the value of other designs for seizure cluster studies, and 5) unique challenges of future trial paradigms for seizure clusters. By focusing on novel endpoints and technologies with value to patients, caregivers, and clinicians, data obtained from future studies can benefit the diverse patient population that experiences seizure clusters, providing more effective, appropriate care as well as alleviating demands on healthcare resources.

PURPOSE/OBJECTIVE:Neurofibromatosis type 2 (NF2) and schwannomatosis (SWN) are genetically distinct tumor predisposition syndromes with overlapping phenotypes. We sought to update the diagnostic criteria for NF2 and SWN by incorporating recent advances in genetics, ophthalmology, neuropathology, and neuroimaging. METHODS:We used a multistep process, beginning with a Delphi method involving global disease experts and subsequently involving non-neurofibromatosis clinical experts, patients, and foundations/patient advocacy groups. RESULTS:We reached consensus on the minimal clinical and genetic criteria for diagnosing NF2 and SWN. These criteria incorporate mosaic forms of these conditions. In addition, we recommend updated nomenclature for these disorders to emphasize their phenotypic overlap and to minimize misdiagnosis with neurofibromatosis type 1. CONCLUSION/CONCLUSIONS:The updated criteria for NF2 and SWN incorporate clinical features and genetic testing, with a focus on using molecular data to differentiate the 2 conditions. It is likely that continued refinement of these new criteria will be necessary as investigators study the diagnostic properties of the revised criteria and identify new genes associated with SWN. In the revised nomenclature, the term "neurofibromatosis 2" has been retired to improve diagnostic specificity.

INTRODUCTION AND PROBLEM STATEMENT/UNASSIGNED:Neuroimmunology is a rapidly evolving subspecialty. At this time, fellowship training is not standardized. Discrepancies exist in fellowship programs across the United States, including in faculty expertise in rarer neuroimmunologic conditions. Many graduating fellows feel uncomfortable managing the full spectrum of diseases within neuroimmunology. OBJECTIVES/UNASSIGNED:To evaluate the feasibility and efficacy of a series of live, virtual, interinstitutional seminars educating neuroimmunology fellows on topics that may be infrequently encountered by trainees. METHODS AND CURRICULUM DESCRIPTION/UNASSIGNED:A steering committee of 6 neuroimmunology and multiple sclerosis fellowship program directors selected 18 topics felt to be high yield but representing unique areas of expertise. A live, interactive seminar series was organized. Recognized experts on each topic led seminars using a teleconferencing platform over the 2020-2021 academic year. Recordings were subsequently made available for asynchronous learning. Trainees were surveyed before and after the seminar series and comfort levels with each topic were recorded. RESULTS AND ASSESSMENT DATA/UNASSIGNED:< 0.0001). DISCUSSION AND LESSONS LEARNED/UNASSIGNED:A year-long series of live, interactive, interinstitutional seminars focusing on unique topics within a single subspecialty represents an effective way to increase trainee comfort levels with such topics.

INTRODUCTION:This study investigated a combination of eight embedded performance validity tests (PVTs) derived from commonly administered neuropsychological tests to optimize sensitivity/specificity for detecting invalid neuropsychological test performance. The goal of this study was to evaluate what combination of these common embedded PVTs that have the most robust predictive power for detecting invalid neuropsychological test performance in a single diverse clinical sample. METHOD:Eight previously validated memory- and nonmemory-based embedded PVTs were examined among 231 patients undergoing neuropsychological evaluation. Patients were classified into valid/invalid groups based on four independent criterion PVTs. Embedded PVT accuracy was assessed using standard and stepwise multiple logistic regression models. RESULTS:Three PVTs, the Brief Visuospatial Memory Test-Revised Recognition Discrimination (BVMT-R-RD), Rey Auditory Verbal Learning Test Forced Choice, and WAIS-IV Digit Span Age Corrected Scaled Score, predicted 45.5% of the variance in validity group membership. BVMT-RD independently accounted for 32% of the variance in prediction of independent, criterion-defined validity group membership. CONCLUSIONS:This study demonstrated the incremental predictive power of multiple embedded PVTs derived from common neuropsychological measures in detecting invalid test performance and those measures accounting for the greatest portion of the variance. These results provide guidance for evaluating the most fruitful embedded PVTs and proof of concept to better guide selection of embedded validity indices. Further, this offers clinicians an efficient, empirically derived approach to assessing performance validity when time restraints potentially limit the use of freestanding PVTs.

Switching between enzyme replacement therapies (ERT) and substrate reduction therapies (SRT) in patients with type 1 Gaucher disease (GD1) is not uncommon; however, the reasons for switchng treatments have not been explored in detail. Data from the Gaucher Outcome Survey (GOS), an international registry for patients with confirmed GD, were used to evaluate the reasons for, and consequences of, switching between these treatment types. Of the 1843 patients enrolled in GOS on 25 February 2020, 245 had undergone a treatment switch: 222 from initial ERT to SRT (of whom 88 later switched back to ERT) and 23 from initial SRT to ERT. The most common reasons for ERT-SRT switching were duration of infusion (25.4%), drug shortage (22.0%), and adverse events (AEs; 11.9%), and for SRT-ERT switching, AEs (63.6%), lack of beneficial effect (16.4%), and participation in a clinical trial (9.1%). Bodyweight and hematologic parameters largely remained stable before and after switching between ERT and SRT, although with substantial variation between patients. These findings contribute to understanding why treatment switching occurs in patients with GD, and may help physicians recognize the real-world impact of treatment switching between ERT and SRT for patients with GD.

Non-motor symptoms of Parkinson's disease (PD) such as dysautonomia and REM sleep behavior disorder (RBD) are recognized to be important prodromal symptoms that may also indicate clinical subtypes of PD with different pathogenesis. Unbiased clustering analyses showed that subjects with dysautonomia and RBD symptoms, as well as early cognitive dysfunction, have faster progression of the disease. Through analysis of the Parkinson's Progression Markers Initiative (PPMI) de novo PD cohort, we tested the hypothesis that symptoms of dysautonomia and RBD, which are readily assessed by standard questionnaires in an ambulatory care setting, may help to independently prognosticate disease progression. Although these two symptoms associate closely, dysautonomia symptoms predict severe progression of motor and non-motor symptoms better than RBD symptoms across the 3-year follow-up period. Autonomic system involvement has not received as much attention and may be important to consider for stratification of subjects for clinical trials and for counseling patients.

Smart health applications have received significant attention in recent years. Novel applications hold significant promise to overcome many of the inconveniences faced by persons with disabilities throughout daily living. For people with blindness and low vision (BLV), environmental perception is compromised, creating myriad difficulties. Precise localization is still a gap in the field and is critical to safe navigation. Conventional GNSS positioning cannot provide satisfactory performance in urban canyons. 3D mapping-aided (3DMA) GNSS may serve as an urban GNSS solution, since the availability of 3D city models has widely increased. As a result, this study developed a real-time 3DMA GNSS-positioning system based on state-of-the-art 3DMA GNSS algorithms. Shadow matching was integrated with likelihood-based ranging 3DMA GNSS, generating positioning hypothesis candidates. To increase robustness, the 3DMA GNSS solution was then optimized with Doppler measurements using factor graph optimization (FGO) in a loosely-coupled fashion. This study also evaluated positioning performance using an advanced wearable system's recorded data in New York City. The real-time forward-processed FGO can provide a root-mean-square error (RMSE) of about 21 m. The RMSE drops to 16 m when the data is post-processed with FGO in a combined direction. Overall results show that the proposed loosely-coupled 3DMA FGO algorithm can provide a better and more robust positioning performance for the multi-sensor integration approach used by this wearable for persons with BLV.