Integrity of the Inferior Cerebellar Peduncle Correlates with Ambulatory Function after Hemorrhagic Stroke

•The inferior cerebellar peduncle (ICP) conveys proprioceptive information.•ICP degeneration occurs with the corticospinal tract's injury.•ICP degeneration is associated with reduced walking after intracerebral hemorrhage. Cerebro-cerebellar connectivity plays a critical role in motor recovery after stroke; however, the underlying mechanism of walking recovery is unclear. The dorsal spinocerebellar pathway has been suggested as a biomarker of poststroke ambulatory function. We aimed to explore the association between ambulatory function and the dorsal spinocerebellar pathway's integrity after intracerebral hemorrhage (ICH). Twenty-seven patients with ICH who were admitted for inpatient rehabilitation during the subacute phase of stroke and 27 age-matched healthy controls were included retrospectively. Ambulatory function was assessed using the Berg Balance Scale and Mobility score. We measured the fractional anisotropy (FA) values of the corticospinal tract (CST) and inferior cerebellar peduncle (ICP) as the final route of the dorsal spinocerebellar pathway. The FA laterality indices, representing the degree of degeneration, were calculated. A Spearman correlation analysis and multivariate linear regression models were used to determine the associations between the FA laterality indices and ambulatory function. An FA reduction was found in both the ipsilesional CST and contralesional ICP of the patients. The ICP FA laterality index exhibited a moderate correlation with ambulatory function (Berg Balance Scale, ρBBS=0.589; Mobility score, ρMS=0.619). On dividing the patient group into the moderate (mRS 3, 4) and severe disability (mRS 5) groups, a stronger correlation was found (ρBBS=0.777, ρMS=0.856, moderate disability; ρBBS=0.732, ρMS=0.797, severe disability). The ICP FA laterality index and age were independently associated with the Mobility score (R2=0.525). ICP degeneration occurs after ICH, and its degree is associated with ambulatory function after ICH.