Paroxysmal cerebellar ataxia.

This report describes the clinical features of 13 cases of periodic, paroxysmal cerebellar ataxia. A family history suggestive of an autosomal dominant disorder was present in 10 cases, the first two reported Australian families involved with this disorder. Variation in the age of onset, frequency of attacks and the presence of distinct symptom complexes within one kindred confirm the heterogeneous nature of this disorder. CT head scans were performed on nine cases and were normal in eight. EEG findings were abnormal in six of nine performed. Treatment with acetazolamide resulted in abolition of paroxysms in nine of the 10 treated cases. In addition, two children had dramatic improvement in previously impaired gross and fine motor skills.