LEVODOPA IMPROVES SPATIAL CONTRAST SENSITIVITY IN PARKINSONS-DISEASE

Objective.-To study the effect of levodopa on the visual contrast sens itivity of patients with Parkinson's disease. Design.-Contrast sensiti vity of patients was measured before and after levodopa administration . Patient contrast sensitivity was compared with that of normal contro ls by repeated-measures analyses of variance. Setting.-Parkinson's dis ease research center associated with private neurology practice. Patie nts.-Fifteen patients with idiopathic Parkinson's disease (eight men, seven women; mean age, 71.8 years) and 22 normal controls (10 men, 12 women; mean age, 68.0 years) volunteered for the study. Intervention.- Levodopa/carbidopa (Sinemet). Main Outcome Measure.-Change in contrast sensitivity of parkinsonian patients.Results.-Following levodopa trea tment, the contrast sensitivity of parkinsonian patients improved sign ificantly at the three lowest spatial frequencies tested (0.4, 1, and 2 cycles per degree). Conclusions.-Levodopa improves low-frequency con trast sensitivity in parkinsonian patients. Initially deficient contra st sensitivity in such patients may be restored to near normal levels by levodopa therapy.