Risk factors for loss of epithelial flap integrity in laser-assisted subepithelial keratectomy surgery

Abstract

To evaluate risk factors leading to loss of epithelial flap integrity in laser-assisted subepithelial keratectomy (LASEK). Boston Eye Group, Brookline, Massachusetts, USA. Retrospective case study. This retrospective chart review was performed for LASEK surgeries that occurred between January 2009 and October 2013. Logistic regression was performed to determine whether epithelium preservation was correlated with age, sex, sphere, cylinder, spherical equivalent (SE), keratometry, and central corneal thickness (CCT). The study reviewed 1009 eyes of 509 patients with a mean age of 29.1years±12.2 (SD). The mean preoperative spherical refraction was -4.7±2.5 diopters (D), and the mean preoperative cylinder was -1.1±0.8 D. The mean preoperative decimal corrected distance visual acuity was 1.01±0.07. Single-sheet mobilization of the loosened epithelium flap was found in 72.3% of cases. Fragmented preservation events occurred in 17.6% of cases; the flap was discarded in 10.0% of cases. Epithelium preservation was significantly correlated with age (P=.048) but not with other parameters (P>.05 for sex, sphere, cylinder, SE, keratometry, CCT, and surgeon experience). Epithelial flap dissection was less likely to lead to a single epithelial sheet in patients older than 50years than in younger patients (56.3% versus 74.9%). The mean postoperative decimal uncorrected distance visual acuity (UDVA) at 3months was 0.98±0.08. There was no statistical difference in postoperative UDVA between the undiscarded flap group and discarded flap group (P=.128). Successful dissection of single-sheet epithelial flap diminished with age. No author has a financial or proprietary interest in any material or method mentioned.