Cerebellar Atrophy in Pediatric-Onset Opsoclonus-Myoclonus-Ataxia Syndrome: A Large International Cohort Study

Authors

• Rebecca MacRae
• Kierstin Hederstedt
• Christopher Cortina
• Kumaran Deiva
• Andrea Klein
• Ming Lim
• Thomas Rossor
• Elizabeth A Sokol
• Yasmin Khakoo
• Nikita Malani Shukla
• Timothy E Lotze
• Wendy G Mitchell
• Sarah Hopkins
• Bo Zhang
• Mark P Gorman

Language

English

Publication Date

9-1-2026

Journal

Neurology Neuroimmunology & Neuroinflammation

DOI

10.1212/NXI.0000000000200619

PMID

42462179

Abstract

Background and objectives: Pediatric-onset opsoclonus-myoclonus-ataxia syndrome (POOMAS) is a rare, neuroinflammatory syndrome that targets the cerebellum and can cause irreversible cerebellar structural changes, namely cerebellar atrophy. We investigated the frequency of cerebellar atrophy, as well as associated risk factors and functional outcome measures, using the largest active POOMAS registry.

Methods: This was a retrospective observational study of participants with POOMAS with disease onset from 1995 to 2025 using data from the multinational, multicenter POOMAS registry. Variables were compared between the cerebellar atrophy subgroups using the Fisher exact test or Wilcoxon rank-sum test.

Results: Of participants with follow-up imaging, cerebellar atrophy developed in 9.5% (6/63) of those with an MRI scan obtained at least 6 months after disease onset and 12.5% (3/24) with an MRI scan obtained at least 48 months after disease onset. Half of the participants who developed cerebellar atrophy (3/6) were identified more than 48 months after disease onset. Cerebellar atrophy was associated with older age at diagnosis (p = 0.023), but not with other demographic or clinical characteristics. There were no statistically significant differences in functional outcome measures or educational setting.

Discussion: The overall frequency of cerebellar atrophy was likely underestimated in this study because of the lack of standardized MRI timing and the large number of patients without MRI scans beyond 48 months.

Keywords

Humans, Female, Opsoclonus-Myoclonus Syndrome, Male, Atrophy, Retrospective Studies, Cerebellum, Magnetic Resonance Imaging, Child, Child, Preschool, Registries, Adolescent, Cohort Studies

Published Open-Access

yes

Recommended Citation

MacRae, Rebecca; Hederstedt, Kierstin; Cortina, Christopher; et al., "Cerebellar Atrophy in Pediatric-Onset Opsoclonus-Myoclonus-Ataxia Syndrome: A Large International Cohort Study" (2026). Faculty, Staff and Students Publications. 7707.
https://digitalcommons.library.tmc.edu/baylor_docs/7707