Changes of electrooculogram (EOG) in Parkinson's disease.

Twenty Parkinsonian patients and 20 control subjects were compared with respect to their electrooculographic findings. It was found that Parkinsonian patients are distinguished from controls by their significantly lower mean EOG ratios. L-dopa treatment restored EOG ratios to control values. The findings are interpreted as indicating an association of Parkinson's disease with metabolic changes in the melanin-containing cells of the pigment epithelium.