Keywords: autosomal dominant cerebellar ataxia, clinical staging, electronystagmographic features

Abstract: Electronystagmography (ENG) was performed in 21 patients from 11 families with autosomal dominant cerebellar ataxia (ADCA). The ENG was abnormal in all patients and related with the clinical evolution of the disease. Qualitative alterations (dysmetria and asymetria) and a better response to caloric than rotational test was found in patients with mild ataxia; non inhibition with optic fixation and hyporeflexia (rotational or caloric test) was associated with moderate ataxia and, finally, in patients with severe ataxia (walk with support or wellchair bound), areflexia in one or more tests (optokinetic nystagmus, rotational and caloric test) was the rule. Concluding, the ENG is important for the early diagnosis, follow up and genetic counselling of ADCA.