Work

Custom air puff-derived biomechanical variables in a refractive surgery screening setting: Study from 2 centers

Year: 2018

Type: article

Abstract: Purpose To assess the ability of air puff-derived biomechanical variables to predict surgeon-perceived candidacy for laser in situ keratomileusis (LASIK). Setting Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, and Emory Eye Institute, Emory University, Atlanta, Georgia, USA. Design Retrospective case series. Methods Data were collected from refractive surgery screening examinations by 2 surgeons at 2 centers. Disqualified cases (19 eyes and 28 eyes from each surgeon) were judged not to be candidates based on available data including standard variables from the Ocular Response Analyzer. Controls consisted of LASIK candidates (n = 26 and 23). Three custom biomechanical variables not available during screening were calculated and compared by group and surgeon. Results The hysteresis loop area was significantly different between disqualified cases and controls for both surgeons (Surgeon 1: controls, 121.50 ± 25.38 [SD], disqualified, 107.62 ± 18.50, P = .04; Surgeon 2: controls, 135.89 ± 22.47, disqualified, 106.11 ± 16.40, P < .001). The area under the curves of the receiver operating characteristics and the cutoff values were statistically significant for the concavity minimum and hysteresis loop area for Surgeon 1 and for all variables except concavity minimum for Surgeon 2. The hysteresis loop area had the highest odds ratio (Surgeon 1, 4.48, Surgeon 2, 20.00). Adjusted R2 in best-subsets regressions were 40.2% for Surgeon 1 and 62.9% for Surgeon 2. Conclusions The hysteresis loop area was predictive of which patients were disqualified for LASIK at different sites. Certain measures of the corneal dynamic response to an air puff might serve as correlates to clinically perceived ectasia risk.

Source: Journal of Cataract & Refractive Surgery

DOI: 10.1016/j.jcrs.2018.03.022

Authors: Vinicius S. De Stefano, Ibrahim Seven, Bradley J. Randleman, William J. Dupps