Unilateral Ectasia 5 Years after KLEx in the Absence of Recognized Risk Factors: A Clinical Case Report

Introduction

Keratorefractive lenticule extraction (KLEx) is the preferred refractive surgical method for the treatment of myopia and myopic astigmatism, with its frequency of application steadily increasing [1]. Compared to laser-assisted in situ keratomileusis (LASIK), KLEx offers several advantages, including the absence of flap-related complications, reduced damage to the subbasal nerve plexus, and a lower incidence of dry eye [2]. Furthermore, the risk of ectasia, one of the most serious complications associated with corneal refractive surgery, is considered lower with KLEx [2]. The reduced risk of ectasia associated with KLEx is theoretically attributed to the preservation of the collagen network in the anterior stroma, the smaller vertical incision required compared to LASIK, and the higher proportion of residual uncut stromal tissue [2], [3]. Conversely, clinical studies indicate that the changes in biomechanical parameters following LASIK and KLEx are comparable [4], [5]. Currently, no in vivo clinical evidence supports the theoretical superiority of KLEx in reducing the risk of ectasia relative to LASIK. To date, literature reports indicate that ectasia developed in 24 eyes of 13 patients following KLEx, with 12 of these eyes lacking any preoperative risk factors [1], [6], [7]. In this case report, we describe a patient with preoperative normal corneal topography who developed unilateral ectasia following KLEx. Our objective was to highlight the necessity for comprehensive studies that investigate the impact of KLEx on corneal biomechanics in a more detailed manner.

Publication History

Received: 03 November 2024

Accepted: 15 January 2025

Article published online:
27 March 2025

• References

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