Light Scattering and Optical Aberration as Objective Parameters to Predict Visual Deterioration in Cataracts

Abstract

Abstract: : Purpose:We have demonstrated that the ocular higher-order aberrations (OHA) and the posterior light scattering (PLS) correlate significantly with the contrast sensitivity (CS) in eyes with cataract (Kuroda, AJO 2002). We have also developed a method to evaluate anterior light scattering (ALS) objectively (Kuroda, JRS 2002). In this study, we investigated the relationship between CS and OHA, PLS or ALS in eyes with mild cortical or nuclear cataract and if the visual deterioration can be predicted objectively with these parameters. Methods: Twenty two eyes with mild nuclear cataract, 41 eyes with mild cortical cataract, and 11 normal eyes were examined (total 74 eyes). Wavefront ocular aberrations for central 4mm diameter were measured using Hartmann-Shack (H-S) aberrometer (Topcon Wavefront Analyzer KR-9000PW) and the OHA was calculated with Zernike polynomials up to 4th order. The ALS was calculated from the spot size of H-S images and the PLS from Scheimpflug images. The relationship between the area under the contrast sensitivity function (AUCSF) and the OHA, ALS, or the PLS was examined. Results: The AUCSF moderately correlated with OHA (R²=0.243, P<0.001, Spearman), ALS (R²=0.187, P<0.001), and PLS (R²=0.252, P<0.001). The multiple linear backward stepwise regression analysis revealed that the AUSCF was well predicted from the linear combination of these parameters (R²=0.494, P<0.001). Conclusions:The light scattering and the higher-order aberration are parameters to predict visual deterioration objectively and may be useful to follow up patients with cataract.

Keywords: optical properties • contrast sensitivity • cataract