diffuse lamellar keratitis after lasik: prevalence, natural course, and final visual outcomes in stage iii or iv

purpose: to evaluate the prevalence, natural course, and final visual acuity in patients with stages iii or iv of diffuse lamellar keratitis (dlk) following laser in situ keratomileusis  (lasik). methods: in this descriptive study, records of all the patients who underwent lasik surgery in two private excimer laser clinics were reviewed. according to linebarger- lindstrom-hardten classification, ocular findings of patients with dlk were classified. there was no preoperative systemic or corneal contraindication for lasik. age, preoperative refraction and best corrected visual acuity (bcva), type and duration of treatment, postoperative refraction, topography, final bcva, possible side effects of medications and complications were reviewed.   results: out of 4097 eyes of 2131 patients, dlk above stage ii developed in 28 eyes (0.68%) of 14 patients (0.66%). dlk was in stage ii-iii in 78.6%, stage iii in 10.7%, and stage iv in 1.7%. none of these patients had history of allergies. treatment consisted of frequent betamethasone drops alone or with ointment and oral systemic prednisolone. interface irrigation was not performed in any patients during the course of treatment. average interval from lasik to diagnosis was 3±1.5 days. patients were treated for an average duration of 20±13.2 days and were followed for an average duration of 11±10 months. average preoperative bcva was 0 logmar (20/20) and final post lasik and dlk vision remained the same. conclusion: prevalence of dlk stages iii and iv is considered insignificant as compared to the enormous number of candidates for lasik surgery (0.68%). all patients with dlk stages iii and iv responded well to immediate topical and systemic corticosteroid therapy and on follow up there was no adverse effect on final bcva.