An Objective Approach for Prescribing Visual Acuities Through Diopter Values

Abstract

Many factors, including the cornea, the lens, and the irregular shape of the eyeball, might influence the visual acuity (VA) of the eye. Ocular aberrations (OAs) are induced by these imperfections, and the normalized Zernike expansion is a typical approach for describing OAs. Customarily, estimating VA of the eye has included procedures that are subjective in nature and conducted through the eye chart. Also, it has been used conversion formulas to convert lower-order aberration to diopters. However, there is no proper approach to convert the diopter values to VA. Intending to avoid the drawbacks of subjective techniques of predicting VA and for accurating the prescribing through the OAs, unlike prior work, we propose an objective approach to determine the impact of Zernike mode(s) corresponding to an ocular aberration on VA using an objective image quality (IQ) metric which is Neural Sharpness (NS). Proposed approach leads to get mathematical relationship between VA and diopters. The Summed Square of Residuals (SSE), Root Mean Square Error (RMSE), and R2 approach confirm the accuracy and the validity of the model. This relationship can be employed to estimate the VA of any ocular aberration in terms of diopters. Also, the proposed relation can be used to assess the efficacy of refractive treatments.