Relationship between damage to the cerebellar peduncles and clinical disability in multiple sclerosis

Purpose: To assess whether a structural disconnection between the cerebellum and the cerebral hemispheres contributes to cerebellar and brainstem symptoms in multiple sclerosis (MS). Materials and Methods: This study was approved by the local ethics committee, and written informed consent was obtained from each participant. Brain T2 lesion load, cerebellar white matter and gray matter volumes, and tract-specific measures of the middle and superior cerebellar peduncles were derived from 172 patients with MS and 46 control subjects. Predictors of clinical impairment, which was determined at ambulation and with cerebellar and brainstem functional system scores, were identified by using random forest analysis. Results: Of the 172 patients, 112 (65%) had middle cerebellar peduncle T2 lesions and 74 (43%) had superior cerebellar peduncle T2 lesions. T2 lesions in the middle and superior cerebellar peduncles were more common in clinically impaired patients than in unimpaired patients (P =.05 to