Indices and Screening Tests for Subclinical Keratoconus

Chapter

Abstract

Iatrogenic corneal ectasia is the most dreaded complication after laser in situ keratomileusis (LASIK). It induces similar clinical features to those of keratoconus. Topographically, it usually corresponds to progressive enlargement of the curvature in the inferior paracentral zone, inducing a decline in best corrected visual acuity. Based on a large series of cases reported in the literature, Randleman et al. [1] proposed a score that can be used to predict the risk of ectasia (Ectasia Risk Score) in order to prevent the development of post-LASIK corneal ectasia. This score takes into account the preoperative topographic appearance, the preoperative central corneal thickness, the residual posterior wall, the patient’s age, and the planned correction. Among these various parameters, the presence of undiagnosed early keratoconus is the main risk factor for post-LASIK ectasia [2]. It is therefore very important to detect early keratoconus, and corneal topography is certainly the reference examination that should be systematically performed as part of the preoperative assessment prior to refractive surgery.

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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Rothschild FoundationParisFrance

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