Individualized Fixel-Based and Group-Level Voxel-Based Analyses Reveal Structural Abnormalities in Pediatric Anti-NMDAR Encephalitis
Abstract number :
3.446
Submission category :
5. Neuro Imaging / 5A. Structural Imaging
Year :
2025
Submission ID :
1438
Source :
www.aesnet.org
Presentation date :
12/8/2025 12:00:00 AM
Published date :
Authors :
Presenting Author: Janine Taitt-Tap, MBBS – The Medical College of Wisconsin, Milwaukee
Daniel Ackom, MS – Marquette University and Medical College of Wisconsin Joint Department of Biomedical Engineering
Lileth Mondok, MD – The Medical College of Wisconsin, Milwaukee
Ricardo Vega, MS – Marquette University and Medical College of Wisconsin Joint Department of Biomedical Engineering
Andrew Crow, BA – The Medical College of Wisconsin, Milwaukee
Scott Beardsley, PhD – Marquette University and Medical College of Wisconsin Joint Department of Biomedical Engineering
Brian Schmit, PhD – Marquette University and Medical College of Wisconsin Joint Department of Biomedical Engineering
Pradeep Javarayee, MD MBA – The Medical College of Wisconsin, Milwaukee
Rationale: Pediatric anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis presents with seizures and diverse neuropsychiatric symptoms, yet conventional MRI is frequently normal. Advanced imaging reveals subtle structural changes. This study applies fixel-based analysis (FBA) to detect patient-specific white matter abnormalities and voxel-based morphometry (VBM) for group-level gray matter assessment.
Methods: VBM was applied to T1-MPRAGE data from 12 patients and 12 matched controls. Tissue segmentation and normalization preceded group comparisons using independent t-tests controlling for age, sex, and intracranial volume, with gray matter volume (GMV) differences corrected for multiple comparisons (FWE, p < 0.05). Diffusion FBA was performed in 4 patients versus 20 age- and sex-matched Human Connectome Project controls, with fiber density and cross-section (FDC) metrics derived from whole-brain tractography. Tract-specific masks enabled patient-level Z-scores, visualized via FDC maps and spider plots.
Neuro Imaging