[Electrophysiological findings in patients with SCA6]

The major symptom of spinocerebellar ataxia type 6 (SCA6) is progressive cerebellar ataxia. MRI revealed isolated cerebellar atrophy without brainstem and cerebral involvement. Up to the present electrophysiological abnormalities in patients with SCA6 have not been intensively investigated. We performed electrophysiological examination, such as multi-modality evoked potentials, in 10 patients with SCA6. We analyzed the electrophysiological data including the results previously reported. When compared with SCA1, 2 and MJD, specific findings in electrophysiological studies are obscure in SCA6. Existence of subclinical lesions in peripheral nerves, pyramidal tract, auditory pathway, visual pathway, and sensory pathway was suggested in some cases with SCA6. It is important to consider the effect of age, because age at onset is relatively late in SCA6.