Suberoylanilide Hydroxamic Acid Versus Mitomycin C: Comparative Study of Toxicity in Adjunctive Treatment of Corneal Haze After PRK in Rabbit Model
Narrative Responses:
Purpose
Mitomycin C (MMC) is widely used as an adjunct at the time of PRK to inhibit corneal haze. Recent reports have reported cytotoxic effects of MMC on the corneal endothelium. We recently demonstrated that SAHA can inhibit corneal haze with efficacy similar to MMC without significant keratocyte or endothelial toxicity.
Methods
Eighteen New Zealand white rabbits underwent -9D PRK (Alcon) followed by a single topical application of MMC (0.02% for 2min) or SAHA (25uM for 5min). Slit-lamp biomicroscopy graded corneal haze and Specular biomicroscopy analyzed endothelial cell counts prior to PRK, after PRK, and at 1-, 2-, and 4-week postoperatively. Corneas were harvested one-month and four-month after PRK/treatment.
Results
Rabbit corneas treated with SAHA following PRK treatment showed no difference in endothelial cell count or anterior stromal keratocyte viability when compared with corresponding controls. MMC treated corneas showed complete absence of anterior stromal keratocytes and significant reduction of endothelial cells (up to 50%) at 2 tested time points.
Conclusion
Compared with MMC, SAHA provides similar efficacy in reducing PRK-induced corneal haze with no cytotoxicity to corneal keratocytes or endothelial cells. SAHA has potential to offer a safer long-term adjunctive treatment for treating PRK-induced haze without major adverse effects. More studies are warranted.