CONTRAST THRESHOLDS OF DIABETIC PATIENTS DETERMINED BY VECP AND PSYCHOPHYSICAL MEASUREMENTS

Abstract
VECP [visual evoked cortical potential] to checkerboard pattern reversal (12 Hz reversal) at different contrast levels were measured in normal subjects and in patients suffering from diabetes mellitus, with visual acuities > 0.8. VECP contrast threshold was obtained by extrapolating VECP amplitude vs. contrast on a log scale to 0 .mu.V. Results were compared with psychophysical thresholds. Both VECP and psychophysical contrast thresholds were significantly higher in the diabetic patients than in the normal subjects.