Computerized tomography in hereditary ataxias.

Cranial CT in 39 patients (23 belonged to 8 families) with four different groups of hereditary ataxia (HA) showed mainly three combinations of atrophic findings: (1) cerebellar ataxia (CA, n=17) had marked atrophy of the cerebellum and/or the brain stem combined with moderate cerebral atrophy; (2) an intermediate group consisting of hereditary spastic paraplegia (HSP, n=10) and Friedreich's ataxia (FA, n=7), both with moderate infra- and supratentorial atrophy; (3) atrophy was hardly demonstrated in the group of Charcot-Marie-Tooth disease (CMT, n=5). HA cases with atrophy could be distinguished from multiple sclerosis (MS) by CT.