Ocular motility in Parkinson's disease

Introduction: Parkinson's disease is associated with multiple abnormalities of both the afferent and efferent visual systems. Blepharospasm, paucity of blinking, apraxia of lid opening, visual neglect, reduced vergence, reduced upgaze, and blurred vision are reported findings in these patients. The association of these findings with the disease, and their duration, severity, and treatment have not been systematically investigated. Patients and Methods: Patients with Parkinson's disease were prospectively examined. An age-matched control group was recruited from accompanying family members and volunteers. Data recorded included presence of visual complaint, the severity of the Parkinson's disease by Hoehn and Yahr Stage (scale=1 to 5), duration of disease, pharmacologic therapy, visual acuity, ocular motility, accommodation, convergence amplitudes, and the near point of convergence. Results: Thirty-nine patients were entered into each group, each with 21 men and 18 women. The average patient had had the disease for 6.9 years with a severity index of 2.6. Asthenopia, upgaze deficiency, and convergence insufficiency were significantly more common in the patients with Parkinson's disease than in the controls. Mean geometric visual acuity was poorer in the Parkinson's patients (20/39 compared with 20/28; P<.001). Discussion: Visual complaints were significantly more common in the Parkinson's patients than in the age-matched controls. The frequency of ocular abnormalities was not related to the duration of the disease. Increasing severity seemed to be correlated with the presence of convergence insufficiency and a decline in acuity.