Faculty Bibliography

BACKGROUND/OBJECTIVES/OBJECTIVE:Characterizing spinal cord multiple sclerosis (MS) lesions in MRI is critical for diagnosis, monitoring, and treatment evaluation. However, current automated approaches for lesion detection and segmentation are typically designed for specific MRI contrasts or acquisition sites, limiting their generalizability in real-world clinical settings where imaging protocols vary widely. This work proposes a robust multi-site, multi-contrast segmentation framework for spinal cord lesions. METHODS:The segmentation model was trained and evaluated on a large-scale dataset comprising 4428 annotated images from 1849 persons with MS across 23 imaging centers, encompassing six MRI contrasts (T1w, T2w, T2*w, PSIR, STIR, and UNIT1) acquired at 1.5 tesla (T), 3 T, and 7 T. RESULTS: < 0.01). Additional experiments evaluated robustness across spinal levels, acquisition resolutions, binarization thresholds, and quantitative evaluation on external labeled datasets. CONCLUSIONS:https://github.com/ivadomed/seg-sc-ms-lesion-multicontrast.

BACKGROUND AND OBJECTIVES/UNASSIGNED:The aim of this study was to assess the limitations of a traditional twice-daily lecture format and evaluate the feasibility and impact of implementing an academic half-day (AHD) for neurology residents at a multisite academic institution. AHD has the potential to improve attendance, satisfaction, and clinical competency compared with traditional didactics in graduate medical education. However, its feasibility and impact within neurology residency programs remain underexplored, with few adopting this model to date. Coverage logistics, faculty availability, and neurologic emergencies continue to pose challenges, particularly in large, multisite institutions. METHODS/UNASSIGNED:A needs assessment survey was administered to 36 neurology residents (postgraduate year [PGY]2-PGY4) in spring 2024 to evaluate attendance, satisfaction, and suggestions for improvement. Attendance was recorded over 1 month (August 2024). Based on survey feedback, a new 3.5-hour AHD curriculum was developed collaboratively by residents and faculty, held Tuesday mornings every week with varied lecture formats. One resident per class covered urgent clinical duties at each of 3 sites, while faculty and advanced practice providers (APPs) independently conducted rounds. Attendance was recorded for one month after implementation (September 2024), and surveys were distributed to assess satisfaction with both the curriculum and the coverage model. Residency In-Training Examination (RITE) scores were compared between the 2022 and 2024 cohorts (before AHD) and the 2025 cohort (after AHD implementation). RESULTS/UNASSIGNED:= 0.0013). Faculty and APPs reported positive or neutral effects on workflow (82.6% and 100%, respectively) and patient safety (95.6% and 100%, respectively). DISCUSSION/UNASSIGNED:Implementation of AHD across a large, multisite neurology residency program was feasible and associated with higher attendance, improved resident satisfaction, and enhanced RITE performance, without adverse effects on workflow or patient safety. Key factors for success included resident involvement, a targeted needs assessment, and strong coverage support from faculty and APPs.

PURPOSE/OBJECTIVE:To explore efficient encoding schemes for quantitative magnetization transfer (qMT) imaging with few constraints on model parameters. THEORY AND METHODS/METHODS:We combine two recently proposed models in a Bloch-McConnell equation: the dynamics of the free spin pool are confined to the hybrid state, and the dynamics of the semi-solid spin pool are described by the generalized Bloch model. We numerically optimize the flip angles and durations of a train of radio frequency pulses to enhance the encoding of three qMT parameters while accounting for all eight parameters of the two-pool model. We sparsely sample each time frame along this spin dynamics with a three-dimensional radial koosh-ball trajectory, reconstruct the data with subspace modeling, and fit the qMT model with a neural network for computational efficiency. RESULTS:We extracted qMT parameter maps of the whole brain with an effective resolution of 1.24 mm from a 12.6-min scan. In lesions of multiple sclerosis subjects, we observe a decreased size of the semi-solid spin pool and longer relaxation times, consistent with previous reports. CONCLUSION/CONCLUSIONS:The encoding power of the hybrid state, combined with regularized image reconstruction, and the accuracy of the generalized Bloch model provide an excellent basis for efficient quantitative magnetization transfer imaging with few constraints on model parameters.

The purpose of this paper is to confirm previous reports that identified magnetization transfer (MT) as an inherent driver of longitudinal relaxation in brain tissue by asserting a substantial difference between the $T_1$ relaxation times of the free and the semi-solid spin pools. Further, we aim to identify an avenue towards the quantification of these relaxation processes on a voxel-by-voxel basis in a clinical imaging setting, i.e. with a nominal resolution of 1mm isotropic and full brain coverage in 12min. To this end, we optimized a hybrid-state pulse sequence for mapping the parameters of an unconstrained MT model. We scanned 4 people with relapsing-remitting multiple sclerosis (MS) and 4 healthy controls with this pulse sequence and estimated $T_1^f \approx 1.90$s and $T_1^s \approx 0.327$s for the free and semi-solid spin pool of healthy WM, respectively, confirming previous reports and questioning the commonly used assumptions $T_1^s = T_1^f$ or $T_1^s = 1$s. Further, we estimated a fractional size of the semi-solid spin pool of $m_0^s \approx 0.202$, which is larger than previously assumed. An analysis of $T_1^f$ in normal appearing white matter revealed statistically significant differences between individuals with MS and controls. In conclusion, we confirm that longitudinal spin relaxation in brain tissue is dominated by MT and that the hybrid state facilitates a voxel-wise fit of the unconstrained MT model, which enables the analysis of subtle neurodegeneration.

Transcranial direct current stimulation (tDCS) is an emerging treatment for major depression. We recruited participants with moderate-to-severe major depressive episodes for an observational clinical trial using Soterix Medical's tDCS telehealth platform as a standard of care. The acute intervention consisted of 28 sessions (5 sessions/week, 6 weeks) of the left anodal dorsolateral prefrontal cortex (DLPFC) tDCS (2.0 mA × 30 min) followed by a tapering phase of weekly sessions for 4 weeks (weeks 7-10). The n = 16 completing participants had a significant reduction in depressive symptoms by week 2 of treatment [Montgomery-Åsberg Depression Rating Scale (MADRS), Baseline: 28.00 ± 4.35 vs. Week 2: 17.12 ± 5.32, p < 0.001] with continual improvement across each biweekly timepoint. Acute intervention responder and remission rates were 75 and 63% and 88 and 81% following the taper period (week 10).

Background: MOG antibody disorder (MOGAD) is associated with diverse clinical phenotypes, including recurrent and bilateral optic neuritis, acute disseminated encephalomyelitis, and longitudinally extensive transverse myelitis with a predilection for the conus medullaris. Spinal nerve root involvement in this disease has rarely been described.
Objective(s): To describe a case of MOG antibody disorder with an unusual radiographic presentation.
Method(s): A case is described and review of the literature was performed.
Result(s): A 53-year-old previously healthy man presented to our hospital with three weeks of numbness and pain involving his right arm, bilateral lower extremities, and perineum. Neurologic exam was notable for decreased sensation in his right hand and left leg, hyperreflexia in bilateral lower extremities, and an extensor plantar response on the left. MRI spine was notable for multifocal short-segment T2 hyperintense lesions consistent with demyelination. There was also contrast enhancement of the cauda equina nerve roots and focal lobular enhancement of the left S1 nerve root. MRI brain showed several small T2 hyperintense brainstem lesions. He was started on pulse dose intravenous steroids while undergoing extensive work-up for inflammatory, infectious, and neoplastic causes. Serology was notable for mildly elevated ACE. CSF showed elevated protein. Given these laboratory and radiographic findings, an inflammatory etiology such as neurosarcoidosis was initially felt to be most likely. CT chest was negative for evidence of pulmonary sarcoid. He demonstrated clinical improvement with steroids and was discharged on a slow taper. MOG antibody in the serum (by cell-based assay) resulted positive at 1:100, suggestive of demyelination in the setting of MOGAD. The patient opted for monthly IV immunoglobulin (IVIG) maintenance therapy and has been clinically stable. Repeat MRI two months later showed stable areas of spinal nerve root enhancement and decrease in some of the cord lesions.
Conclusion(s): Our case demonstrates that MOGAD should be a diagnostic consideration when MRI shows spinal nerve root enhancement in the appropriate clinical context, especially with the additional presence of CNS lesions that are typical of demyelination. MOGAD can manifest clinically and radiographically in both the central and peripheral nervous system