This work intends to determine the optimal refractive spectacle and scleral lens corrections for keratoconus patients using the visual Strehl (VSX) visual image quality metric and the SyntEyes models with the synthetic biometry of 20 normal eyes and 20 keratoconic eyes. These included the corneal tomography and intraocular biometry. A series of virtual spherocylindrical spectacle and scleral lens corrections spanning the entire phoropter range were separately applied to each eye, followed by ray tracing to determine the residual wavefront aberrations and identify the correction with the highest possible VSX (named a "focus"). To speed up calculations, a smart scanning algorithm was used, consisting of three consecutive scans over increasingly finer dioptric grids. In the dioptric space, the VSX pattern for normal eyes considered over the correction range for either spectacle or scleral lens corrections resembled an hourglass with one distinct focus and a quick drop in VSX away from that focus. For 18 of the 20 keratoconic eyes, the spectacle-corrected VSX pattern resembled a shell that in 9 of the 20 cases showed two foci separated by a large dioptric distance (13.3 ± 4.9 diopters). In keratoconic eyes, scleral lenses also produced hourglass patterns, but with a VSX lower than in normal eyes. The hourglass pattern in dioptric space shows how, in normal eyes, the refracting process automatically funnels practitioners toward the optimal correction. The shell patterns in keratoconus, however, present far more complexity and, possibly, multiple foci. Depending on the starting point, refracting procedures may lead to a local maximum rather than the optimal correction.

中文翻译：

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模拟圆锥角膜屈光矫正策略。

这项工作旨在使用视觉 Strehl (VSX) 视觉图像质量度量和 SyntEyes 模型以及 20 只正常眼和 20 只圆锥角膜的合成生物测定法，确定圆锥角膜患者的最佳屈光眼镜和巩膜镜片矫正。这些包括角膜断层扫描和眼内生物测定。对每只眼睛分别应用一系列跨越整个 phoropter 范围的虚拟球柱眼镜和巩膜镜片校正，然后进行光线追踪以确定残余波前像差并识别具有最高可能 VSX（称为“焦点”）的校正。为了加快计算速度，使用了一种智能扫描算法，包括在越来越精细的屈光度网格上进行三个连续扫描。在屈光空间中，在眼镜或巩膜镜片矫正的矫正范围内考虑的正常眼睛的 VSX 模式类似于沙漏，具有一个明显的焦点，并且 VSX 快速下降远离该焦点。对于 20 只圆锥角膜中的 18 只，眼镜矫正后的 VSX 模式类似于一个壳，在 20 只病例中有 9 只显示两个病灶相隔很大的屈光度距离（13.3 ± 4.9 屈光度）。在圆锥角膜中，巩膜镜片也产生沙漏图案，但 VSX 比正常眼睛低。屈光空间中的沙漏图案显示了在正常眼睛中，屈光过程如何自动引导从业者进行最佳矫正。然而，圆锥角膜中的壳模式呈现出更加复杂的情况，并且可能具有多个病灶。根据出发点，