Ataxic cerebral palsy--clinico-radiologic correlations

Clinico-radiologic correlations, using CT, were studied in 29 patients with ataxic cerebral palsy. The scans were normal or only slightly abnormal in 38%, posterior fossa abnormalities occurred in 28%, and 55% had obvious cerebral abnormalities which always involved the parietal lobes. There were only two cases where the changes were confined to the posterior fossa. Hydrocephalus was present in four, and there was one case of a Dandy-Walker malformation. An absolute association with any clinical subtype was unusual. All cases of simple ataxia had an obviously abnormal scan, but the changes were widespread. Where dysequilibrium was present the scans were either normal or showed widespread change. Only 25% involved the vermis. Although there was some association between hydrocephalus and ataxic diplegia, the majority of this subtype had a normal or only slightly abnormal scan. Most were hypotonic docile infants with delayed speech and motor skills, particularly those with posterior fossa abnormality. Although CT did not predict development well, those with lower IQ's were more likely to have obvious CT change. Where obvious supratentorial change was present, 75% had a history of epilepsy. In ataxic cerebral palsy CT findings are common, but variable. CT change correlates better with IQ and epilepsy than clinical subtype.