Tomographic Predictors of Ectasia Development After Keratorefractive Surgery

imagePurpose:

The aim of this study was to identify the risk factors for postkeratorefractive surgery ectasia in unsuspicious tomographies and to report a new index coined diameter of peak locations (DPLs).

Methods:

All patients who underwent keratorefractive surgery between 2011 and 2018 at Care-Vision Laser Centers, Israel, and later developed ectasia were included. For each ectasia case, 3 matched controls were selected. Demographic and preoperative, intraoperative, and postoperative data were collected. Multivariate analysis was performed to evaluate the interdependence of the variables.

Results:

The retrospective study included 19 ectasia and 58 control eyes. There were no significant differences between the groups in ablation depth (P = 0.73), preoperative spherical equivalent (P = 0.12), percent tissue altered (P = 0.71), residual stromal bed (P = 0.73), and Ectasia Risk Score System (P = 0.60). The anterior and the posterior symmetry index were significantly higher (P