A Portable Visual Acuity Device Used in Diabetic Retinal Screening

Purpose To correlate visual acuity measured with the Optec 800 to the gold-standard Early Treatment Diabetic Retinopathy Study (ETDRS) chart. Design Prospective, cross-sectional study. Methods Forty patients of the Vanderbilt Eye Institute agreed to undergo visual acuity testing. Five patients were excluded because of enucleation or functional blindness of one or both eyes. Two patients were excluded because of poor cooperation during testing. Patients were randomized to one of the two methods and participated in visual acuity testing in a forced-choice manner. The sequence was repeated with the alternate instrument. A total-correct score was calculated for each data set. Results There was no statistically significant difference in scores between the two methods ( P1 = .153, P2 = .307.) Other factors such as gender, age, and instrument testing order did not affect performance. Age was inversely correlated with total correct score. Conclusions In this small cohort, the Optec 800 (Chicago, Illinois, USA) and the ETDRS chart recorded similar visual acuity measurements.