Impairment of smooth pursuit eye movements in patients with multiple system atrophy and idiopathic Parkinson's disease

Objectives: It is well known that patients with multiple system atrophy of cerebellar type (MSA-C) show impaired smooth pursuit eye movements (SPEM) due to their cerebellar pathology. To what extent SPEM are also affected in other MSA subtypes or in idiopathic Parkinson's disease (IPD) is less clear. In this study, we investigated if quantitative measurements of SPEM may help to discriminate between subtypes of MSA as well as between MSA and IPD. Methods: Twenty-seven healthy controls, 17 patients clinically diagnosed as IPD and 11 patients diagnosed as MSA, in different stages of disease, tracked sinusoidal tar…