A novel computerized visual acuity test in children

Abstract

Purpose: To investigate the efficacy of a novel computerized visual acuity test for children—the Seoul National University (SNU) visual acuity test. Methods: Sixty-three children from 1 to 5 years old were included. In a dark room, the children gazed at and followed a circular dot with 50% contrast moving at a fixed velocity of 10 pixels/s on a computer monitor. Eye movement was captured using an Osprey camera (Viewcast, USA) and was expressed as coordinates on a graph. Movements of eye and dot were overlapped on a graph and analyzed. Minimal dot diameters visualized were compared with Teller visual acuity. Results: Average Teller visual acuity was 14.50 cycles/degree and average SNU visual acuity was 2.68 pixels. Teller visual acuity and SNU visual acuity were significantly correlated (p = 0.009). LogMAR visual acuity converted from Teller visual acuity and SNU visual acuity were also significantly correlated (p = 0.019). Conclusions: The devised SNU visual acuity test was found to be significantly correlated with Teller visual acuity and the authors believe that it could be used clinically in children.