Purpose: To investigate the optimal intraocular lens (IOL) corrections for virtual eyes with moderate to severe keratoconus (KC) using ray tracing and comparative analysis of image quality.Setting: Computer simulations conducted using MATLAB-based custom ray-tracing software. Design:The study included 20 eyes generated from a statistical eye model called SyntEyes, which produces eye biometrics for KC eyes for optical simulation.The visual Strehl ratio (VSX) was used to quantify image quality based on optical wavefront analysis. Methods:The eyes underwent various simulated corrections, including spherical and toric IOLs, as well as spherical and toric rigid gas-permeable (RGP) contact lenses, both individually and in combination.Comparisons were made across different correction strategies.Results: Spherical and toric IOLs alone modestly improved VSX to 0.025 0.004 and 0.034 0.005, respectively, from a baseline of 0.013 0.003 (P < .001).By contrast, eyes corrected with toric RGP lenses after IOL implantation demonstrated significantly higher image quality: 0.250 0.014 (spherical IOL) and 0.246 0.014 (toric IOL) (P < .001).However, combining 2 toric elements often led to overcorrection and increased aberrations.
Francis et al. (Tue,) studied this question.