Risk factors for intraoperative epithelial defect in laser in-situ keratomileusis.
OBJECTIVE
To report intraoperative epithelial defects (IED) in eyes undergoing laser in-situ keratomileusis (LASIK).


METHODS
Consecutive interventional case series.


METHODS
Retrospective review of 247 eyes (133 patients) that underwent primary LASIK by a single surgeon at an academic institution using the Hansatome microkeratome. Patient characteristics and variations in preoperative and operative technique were analyzed. The main outcome measure was occurrence of IED (defined as loose epithelium that is > 1 mm or cannot be stably repositioned or absent epithelium). Multivariate logistic regression was performed.


RESULTS
Intraoperative epithelial defects occurred in 24 (9.7%) of 247 eyes. Intraoperative epithelial defects significantly increased with older age (odds ratio [OR] 2.39/decade; 95% confidence interval [CI] 1.46-3.92), thicker preoperative corneal thickness (OR 2.30/50 microm; 95% CI 1.24-4.28), and maintenance of suction ring vacuum during the reverse pass of the microkeratome (OR 1.76; 95% CI 1.01-3.06). The preoperative and intraoperative eye-drop regimen (anesthetic, mydriatics, lubricants, and intraoperative tonometry) had a significant effect on IED risk (OR, 0.163 best vs worst regimen; 95% CI, 0.033-0.792). In patients undergoing bilateral LASIK, the incidence of IED is much higher in the second eye if the first eye developed an IED (57% vs 1%).


CONCLUSIONS
Modifying the eyedrop regimen was the more effective technical approach to decrease the risk of IED. Age and corneal thickness are valuable patient characteristics for preoperative risk assessment. Intraoperative epithelial defects in the first eye is highly predictive of IED in the second eye of the same patient.
Tekwani
Navin H
NH
Cole Eye Institute, The Cleveland Clinic, Ohio 44195, USA.
Huang
David
D
D000328:Adult; D000367:Age Factors; D000368:Aged; D003315:Cornea / Q000473:pathology*; D004847:Epithelial Cells / Q000473:pathology*; D005260:Female; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications; D020731:Keratomileusis, Laser In Situ / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors; D013524:Surgical Flaps