Refractive and Topographical Analyses After Wavefront-Optimized Photorefractive Keratectomy With 75% Angle Kappa Compensation for Myopia.

OBJECTIVE

To evaluate refractive and topographic outcomes following photorefractive keratectomy (PRK) with 75% angle kappa (P-Dist) compensation in myopic eyes.

METHODS

This retrospective study included 127 right eyes of patients with myopia and/or myopic astigmatism, who underwent wavefront-optimized PRK, incorporating 75% P-Dist compensation. Visual, refractive, topographic, aberrometric, and point-spread function (PSF) measurements were recorded preoperatively and at 1, 3, and 6 months postoperatively.

RESULTS

The mean P-Dist was 232.13±121.78 μm (range: 31.69-769.84 μm). Eyes were grouped by mean P-Dist: group-1 (<232.13 μm, small-angle kappa, n=67) and group-2 (>232.13 μm, large-angle kappa, n=60). Preoperative P-Dist correlated with root-mean-square of higher-order aberrations (RMS-HOAs) (r=0.24, P =0.01) and coma (r=0.381, P <0.001). Group-2 had higher preoperative coma ( P =0.001). At 6 months, the percentage of eyes within ±0.50 diopters (D) spherical equivalent and≤0.50 D astigmatism, visual acuity, asphericity, mean pupil power, HOAs, and PSF were similar between the groups ( P >0.05 for all). No correlation was found between preoperative P-Dist and postoperative HOAs or PSF changes ( P >0.05 for all).

CONCLUSIONS

PRK with 75% angle kappa compensation yields comparable refractive and topographical outcomes in myopic eyes with small- and large-angle kappa. In eyes with a significant angle kappa, aligning ablation with P-Dist may not induce additional corneal refractive or topographical changes.