Central flap necrosis after LASIK with microkeratome and femtosecond laser created flaps

PURPOSE: To report nine cases of severe central flap inflammation and necrosis after LASIK. METHODS: A retrospective chart review was conducted on 17,100 LASIK cases performed at two laser centers in Indiana from January 1995 through May 2005. All patients with central lamellar flap necrosis were identified. RESULTS: Severe central flap inflammation and necrosis occurred in nine eyes of eight patients. Six patients underwent flap creation with a mechanical microkeratome and two with a femtosecond laser. Of eight eyes with > 2-month follow-up, one lost at least two lines of best spectacle-corrected visual acuity and two experienced a hyperopic shift in spherical equivalent refraction. Typically, inflammation was minimal the day after surgery, peaked 5 to 10 days later, and subsided by 60 days. Six of nine cases were treated by lifting the flap and irrigating the stromal bed. In each of these cases, few or no inflammatory cells were observed in the stromal bed, the posterior flap surface was intact, and the central portion of the anterior flap had a jelly-like consistency. CONCLUSIONS: Central lamellar flap necrosis appears to differ from diffuse lamellar keratitis because the location of stromal inflammation is not in the flap interface but rather in the flap anterior stroma. Treatment with corticosteroids seemed to have little effect on outcomes. This is thought to be the first documentation of central lamellar flap necrosis following the use of a femtosecond laser.