Purpose: Corneal haze is a severe complication after excimer laser PRK and may lead to a compromised visual performance and regression. Currently, corticosteroids are topically applied to inhibit the appearance of haze. However, this therapy is not always successful in preventing haze. Various animal studies have shown that topical applied mitomycin C reduces keratocyte activity and collagen synthesis and subsequently haze.
Material and methods: We have treated 5 patients (5 eyes) with severe haze and regression after PRK. In all eyes we have mechanically debrided the haze and 0.02 % mitomycin C was applied to the area of previous ablation for 1 minute. In 2 eyes we have only performed the debridement, whereas in 3 eyes we also have performed a re-PRK after the laser ablation the mitomycin was applied. The postop follow-up was 9 months.
Results: In all eyes the surgery and the postop time was without any complications. The haze could be removed in all eyes completely and in the entire postop period recurrent haze was not more than trace. Regression could be eliminated in the three eyes with a re-PRK, whereas the 2 eyes without re-PRK still remained myop. We could not observe any mitomycin C associated complications on the conjunctiva or cornea.
Conclusion: Topical applied mitomycin C seems to be a promising therapy to prevent recurrent haze after a second PRK procedure. As mitomycin C can be associated with a variety of serious complications, it should only be used in patients with high risk of haze.