Topical interferon alpha 2b for corneal haze after excimer laser photorefractive keratectomy

Abstract

Purpose: To determine whether topical interferon alpha 2b (IFN-α) prevents corneal haze after excimer laser photorefractive keratectomy (PRK).Setting: Tertiary referral ophthalmic hospital.Method: A prospective, double-blind, placebo-controlled, randomized study of 31 patients was undertaken. After surgery in a single institution, patients received a drop of either a placebo or IFN-α (5 × 106 IU/ml) four times daily for 4 weeks. The main outcome measures were corneal haze, refraction, and visual acuity.Results: The major side effect of interferon alpha treatment was a significant delay in epithelial healing by a mean of 2 days. The means of the average post-treatment clinical scores for haze in all patients up to 12 months after surgery were 0.46 ± 0.25 for the IFN-α group and 0.64 ± 0.43 for the placebo group (P = .20). Of patients with a correction of greater than 5.00 diopters (D), the IFN-a group had significantly less haze over the course of the study (0.39 − 0.23 versus 0.98 ± 0.50; P = .03). After 12 months, the mean absolute spherical equivalent in the two groups was not significantly different (1.02 ± 1.13 D versus 1.44 ± 2.64 D). There was a tendency toward better uncorrected visual acuity in the INF-a group (P < .10, Kolmogorov-Smirnov).Conclusion: Topical IFN-α may merit further investigation as a treatment to reduce corneal haze after excimer laser PRK for corrections greater than 5.00 D.