Evoked potentials in multiple system atrophy (MSA)

Objectives - To study the involvement of pyramidal tracts and sensory pathw ays in multiple system atrophy (MSA). Materials and methods Evoked potentia l studies were performed in 45 MSA patients suffering from either MSA of ce rebellar type (MSA-C) or MSA of parkinsonian type (MSA-P). Results - Motor evoked potentials were normal in all MSA patients, whereas visual and somat osensory evoked potential abnormalities were found in about 40% of the MSA patients with no significant difference between the cerebellar (MSA-C) and parkinsonian (MSA-P) subgroup. Abnormal latencies of wave III in brainstem auditory evoked potentials were significantly more frequent in MSA-C. Concl usions - Abnormalities of somatosensory, visual and auditory evoked potenti als are frequent findings in MSA, whereas abnormal motor evoked potentials are not a characteristic feature of the disease.