Late traumatic dislocation of laser in situ keratomileusis corneal flaps.

PURPOSE: To report the management and outcome of late-onset traumatic dislocation of laser in situ keratomileusis (LASIK) flaps. DESIGN: Retrospective, observational case series. PARTICIPANTS: Four patients with late-onset LASIK flap dislocation occurring after mechanical trauma at various intervals (10 days-2 months) after the procedure. INTERVENTION: In all cases of postoperative traumatic LASIK flap dislocation, the flap was refloated with scraping and irrigation of the underlying stromal bed within 12 hours of the injury. A bandage contact lens was placed, and a regimen including topical antibiotics and corticosteroids was instituted in all cases. MAIN OUTCOME MEASURES: Best spectacle-corrected visual acuity and complications associated with the surgery were monitored. RESULTS: Postoperative follow-up ranged from 4 to 21 months. Nonprogressive epithelial ingrowth was noted in one patient and diffuse lamellar keratitis developed in another patient. All patients recovered pretrauma spectacle-corrected visual acuity. CONCLUSIONS: Corneal LASIK flaps are prone to mechanical dislocation as late as 2 months after the procedure. Appropriate management results in recovery of optimal visual outcomes.

The use of confocal microscopy in evaluating corneal wound healing after excimer laser keratectomy.

Corneal wound healing following excimer laser keratectomy is the major cause of regression of treatment results. The amount of anterior stromal haze that develops may be influenced by topical medications. Over a period of 6 months, we followed 15 New Zealand white rabbit eyes that underwent excimer laser keratectomy with the VISX 193-nm ArF laser at a fluence of 150 mJ/cm2 for a depth of 130 microns. Eyes were randomized to treatment with prednisolone acetate, diclofenac sodium (Voltaren), a combination of both, and a control group. Drops were administered four times a day for 1 week, two times a day for 3 weeks, and the drops were then tapered. All eyes were reepithelialized by 5 to 7 days. The tandem scanning confocal microscope (TSCM) was used to evaluate the corneal wound in vivo weekly for a month and monthly for 6 months. During the early postoperative period, the TSCM revealed significant anterior stromal keratocyte activation with cell elongation and the spindle-shaped appearance of fibroblasts in all groups. Collagenous stromal scarring was evident initially, then slowly decreased in all treatment groups. This study shows that TSCM is clinically useful for successive in vivo examinations of corneal wounds after excimer laser keratectomy and for comparing the effects of various topical medications.

Comparison of corneal epithelial wound healing rates in scrape vs. lamellar keratectomy injury.

Previous in vivo studies evaluating the effects of growth factors on epithelial regeneration have used the scrape injury model in rabbit eyes. Since growth factors act principally on the mitotic activity of regenerating cells, the rapid wound closure rates following scrape injury may not adequately access the effects of these agents on epithelial repair. In this study, we evaluated the rates of wound healing following scrape (8.6 mm) and lamellar keratectomy (8.6 mm) injury in 25 albino rabbits. Eyes were left untreated or received daily application (two to three times) of (a) Tears Naturale II, (b) 50 mM Tris/NaCl, and (c) commercial vehicle for EGF. Eyes were evaluated daily by fluorescein staining with Ophthalmic Fluoro-Strips followed by clinical photography. The area of staining was quantitated by computer-assisted planimetry and rates calculated by linear regression analysis. Eyes receiving scrape injuries epithelialized by 3 days following surgery. Rates of wound closure in two separate groups (six eyes each) were 25.83 mm2/day (r = 0.96) and 29.56 mm2/day 9r = 0.97). Lamellar keratectomy injuries epithelialized by 7 to 8 days, which is substantially longer than that observed for scrape injuries. Rates of wound healing in two separate untreated groups (8 and 10 eyes) were 10.88 mm2/day (r = 0.95) and 9.00 mm2/day (r = 0.93), respectively, which were not significantly different. Analysis of variance comparing rates of wound closure indicated that lamellar keratectomy injuries heal at a significantly slower rate when compared to scrape injury (p less than 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)