Abnormalties of Ocular Motor Movement in Patients with Parkinson's Disease

ABSTRACT

OBJECTIVE: We investigated the relationship between the severity of the disease and the abnormality of some ocular movements in parkinson's disease. BACKGROUND: Disorders of eye movements have been described in diseases of the basal ganglia for over a century and ocular motor deficits of the saccadic and pursuit system have been reported in parkinsonian patients. METHOD: We studied the electro-oculography of the eye tracking and saccadic movement in 26 patients (11 males, 15 females) with Parkinson's disease. The severity of the disease was divided into two groups by Hoehn & Yahr(H-Y) staging, H-Y stage 1, 2(group A) and H-Y stage 3, 4 (Group B). Some patients antiparkinsonian drugs of L-dopa, dopamine agonist and anticholinergics. RESULT: The velocity of smooth pursuit and the velocity and latency of saccade were calculated and compared between two groups. Eye tracking test revealed decreased pursuit velocity leading to catch-up saccades, but normal phase relationship between eye and target movement, while saccadic eye movement had increased latency. These results showed more profound severity in more advanced stages of the disease. CONCLUSION: We suggest that ocular movement be often chosen as a simple but relevant example of general motor function, as well as criteria for staging of Parkinson's disease and basal ganglia play significant role in ocular movement.