Epithelial Removal and Phototherapeutic Keratectomy for Residual Refractive Error Following LASIK in Eyes With Corneal Epithelial Basement Membrane Degeneration

Abstract

To retrospectively evaluate the efficacy of epithelial removal followed by phototherapeutic keratectomy (PTK) for reducing residual refractive error in eyes with corneal epithelial basement membrane degeneration after LASIK. Eight eyes of four patients with residual refractive error and signs of epithelial basement membrane degeneration after LASIK were followed until their refractive error stabilized. Epithelium was debrided and PTK performed. Refractive error and visual acuity outcomes were analyzed. In the six eyes that underwent LASIK for myopic astigmatism, mean spherical equivalent refraction after LASIK was -1.75 +/- 0.62 diopters (D) and mean astigmatism was +0.75 +/- 0.59 D. After PTK, mean spherical equivalent refraction was -0.33 +/- 0.35 D and mean astigmatism was +0.50 +/- 0.27 D. Mean logMAR uncorrected visual acuity (UCVA) improved from 0.39 +/- 0.31 before PTK to 0.03 +/- 0.05 after PTK. Mean Snellen UCVA improved from 20/50 before PTK to 20/20 after PTK. In two eyes that underwent LASIK for hyperopic astigmatism, mean spherical equivalent refraction after LASIK was +4.38 +/- 0.35 D and mean astigmatism was +3.25 D. After PTK, mean spherical equivalent refraction decreased to +1.56 +/- 0.44 D and mean astigmatism decreased to +2.13 +/- 0.53 D. Mean logMAR UCVA improved from 0.24 to 0.14. Mean Snellen UCVA improved from 20/35 to 20/27. In eyes with epithelial basement membrane degeneration and refractive error after LASIK, epithelial removal followed by PTK may reduce refractive error, both myopic and hyperopic, bringing it close to emmetropia and avoiding the need for traditional stromal enhancement.