Abstract
Purpose: :
Lancaster red green charts are often used for testing visual acuity and refractive error. We developed an application for the ipad and other mobile devices to test visual acuity independent of an ophthalmologist in an attempt to use this as a remote diagnostic tool.
Methods: :
We compared the visual acuity of twenty eyes from ten subjects using standardized Lancaster red green charts at 6m and the ipad application at 10 feet. For statistical evaluation, Pearson correlation coefficients were calculated to demonstrate the accuracy of this newly developed software.
Results: :
The correlation coefficient between the two methods for visual acuity was 0.86 on the green charts and 0.65 on the red charts.
Conclusions: :
We believe that this innovative software could prove to be useful as a simple remote diagnostic tool. The correlation between the current standard and the ipad application is strong for the green charts. We are currently standardizing the luminance of the device and looking at the effect of patent refractive error and age on the correlation of the red charts.
Keywords: visual acuity • refraction