Cerebellar volume correlates with saccadic gain and ataxia in adult Niemann-Pick type C

Background and purposeCerebellar Purkinje cells are known to be highly vulnerable to neuronal pathology in Niemann-Pick type C (NPC), a disease where widespread white matter changes have also been reported. We sought to determine the relationship between white and grey matter cerebellar changes and clinical variables in NPC.Materials and methodsTen adult patients with NPC were matched to control subjects (n = 27) on age and gender. Patients were rated for symptom duration and severity, degree of ataxia, and were assessed for saccadic eye measures. Cerebellar white and grey matter volumes were automatically segmented using the Freesurfer software package.ResultsNPC patients had a significant reduction in both grey and white matter volumes. Volume did not correlate with symptom duration or severity, but did correlate with saccadic gain and ataxia measures.ConclusionsBoth cerebellar grey and white matter volume decreases in adult NPC, and these changes are associated with impairments in saccadic gain and in motor control.

► Cerebellar volume loss in adult Niemann-Pick type C is driven by changes to both white and grey matter.
► Reduced cerebellar volume correlates with ataxia measured on the Brief Ataxia Rating Scale.
► Reduced saccadic gain may be driven by cerebellar and brainstem changes.