Infectious keratitis after photorefractive keratectomy, femtosecond-LASIK and lenticule extraction in a 100,000-eye case series

Abstract

This study evaluates the incidence and outcome of infectious keratitis after laser vision correction by photorefractive keratectomy (PRK), femtosecond LASIK, and keratorefractive lenticule extraction (KLEx) in a retrospective, consecutive, single-institute series. Patients with presumed infectious keratitis between 2011 and 2023 were analyzed. In PRK, manual deepithelialization was done, and mitomycin C was used with spherical equivalents greater than 3 diopters. Femtosecond LASIK and KLEx were performed with an LDV Ziemer laser; the interface was rinsed in both techniques. All treatments received post-operative netilmicin eyedrops. Finally, 106269 eyes of 54278 patients were included; 6 eyes of 6 patients were identified as having infectious keratitis (3 by staphylococci, 3 culture-negative). The overall incidence of infectious keratitis was 0.0056% (0.0164% after PRK, 0.0023% after femtosecond LASIK, 0.1366% after KLEx; Chi2 p<0.00001). The odds ratio for PRK compared to LASIK was 7.2 (p=0.0307); for KLEx compared to LASIK 59.7 (p=0.0008). Presentation after KLEx (2 days) was earlier than after PRK (5, 4, and 5 days) and LASIK (6 and 4 days). In all cases, hourly fortified cefazolin and tobramycin eyedrops were used, with a good response: 3 eyes maintained a 20/20 uncorrected visual acuity; 2 eyes 20/20 with myopic astigmatism; 1 eye ended 20/25 with correction because of irregular astigmatism. In conclusion, infectious keratitis was a rare complication, more common after KLEx and less common after femtosecond-LASIK. Only 3/6 cases had a positive culture. All the cases in our series had a favorable outcome.