Abstract
Abstract: :
Purpose: To evaluate the results after myopic and hyperopic LASIK retreatments and to report the incidence of clinically significant epithelial ingrowth, its surgical treatment, recurrence rate and visual outcome. Methods:555 eyes in 393 patients underwent LASIK enhancement at our facility from January to December 2001 by lifting the corneal flap and reablating the stromal bed with the Autonomous LADARVision 2000 laser. Over 95% of cases were treated with the Moria C/B microkeratome before primary LASIK. We identified all eyes with postoperative clinically significant epithelial ingrowth requiring debridement. The following parameters were studied: influence of ingrowth on visual acuity, risk factors, therapeutic strategies and recurrence after surgical removal. Results: The indications for laser retreatment were residual myopia in 394 eyes (Group 1) and residual hyperopia in 161 eyes (Group 2). The mean pre-enhancement spherical equivalent in Group 1 was -1.30 diopters (D) +/- 0.67 D (SD) (range -0.25 to -3.50D) and in Group 2 +1.20 +/- 0.86 D with a range of +0.25 to +4.50D. At 3 months after enhancement the mean spherical equivalents in Groups 1 and 2 were -0.15 +/-0.32 D (range +0.50 to -2.25D)and +0.19 +/-0.44 D (range -0.50 to +2.00D), respectively. In Group 1 the uncorrected visual acuity (UCVA) was 20/40 or better in 62% of eyes before enhancement and in 97% post-retreatment. In Group 2, the UCVA was 20/40 or better in 78% before enhancement and in 98% postoperatively. The incidence of significant epithelial ingrowth was 6.3% after LASIK enhancement: 24 patients developed unilateral and 6 patients bilateral ingrowth. 14 of the 36 eyes were highly myopic before primary LASIK. Time between primary LASIK and enhancement ranged from 3 to 12 months with a mean of 4.9 months +/-1.9 (SD). Epithelial ingrowth was seen at the 1 month postoperative visit in 21 eyes. Surgical debridement was undertaken at a mean of 4.1+/- 3.4 months (range 2 weeks to 1 year). At the last postoperative visit (minimum 2 months) after debridement all 36 eyes had an UCVA of 20/40 or better, 23 eyes improved to 20/25 or better. Epithelial ingrowth recurred in 23 eyes after initial removal. Redebridement was necessary in 6 eyes of 5 patients, one of which required a total of 3 debridements and re-enhancement laser afterwards. Conclusions: LASIK retreatment for correcting residual myopia and hyperopia proved to be effective with minimal complications. The technique to raise the flap and reablate appeared safe. Postoperative epithelial ingrowth was not uncommon, but successful mechanical debridement secured good final visual outcome.
Keywords: refractive surgery: LASIK • refractive surgery: complications • visual acuity