Evaluation of a risk factor scoring system for corneal ectasia after LASIK in eyes with normal topography

Abstract

Purpose: To assess a previously published risk score system for predicting postoperative LASIK ectasia in eyes with normal preoperative topography.

Methods: A retrospective review of one surgeon's LASIK database was performed for eyes with Randleman ectasia risk scores based on patient age <30 years, preoperative central corneal thickness <510 microm, residual stromal bed thickness <300 microm, and/or a preoperative manifest refraction spherical equivalent >-8.00 diopters that had a minimum follow-up of 1 year. RESULTS Of 1702 eyes with myopic errors and normal topographies, 35 (2.0%) eyes had a combined risk score between 5 and 9 points, 92 (5.4%) eyes had a combined risk score of 4 or higher, and 208 (12.2%) eyes had a combined score of 3 or higher. None of these eyes developed ectasia, whereas 3 eyes with preoperative topographic keratoconus with no other risk factors developed ectasia.

Conclusions: The current risk score system would have eliminated 5.4% of eyes with 4 or more points from LASIK surgery, and would have also required the surgeon to advise an additional 6.8% of eyes with a score of 3 that they were at "moderate risk" and should "proceed with caution." In eyes with normal preoperative topographies, the scoring system may not accurately predict whether patients are at increased risk for developing postoperative LASIK ectasia.