Prophylactic mitomycin C (MMC) can aid in the prevention of corneal haze that can occur following transepithelial photorefractive keratectomy (T-PRK) for patients with myopia, according to findings published in Clinical Ophthalmology.
The researchers retrospectively reviewed records of 120 eyes of 60 patients with low, moderate, or high myopia who underwent T-PRK between 2020 and 2021 at Qassim University in Saudi Arabia. The study authors took into account outcomes on the basis of disease severity and receiving intraoperative 0.02% MMC for 30 to 50 seconds. Low myopia was defined as a spherical equivalent (SE) of -3.00 D or less, moderate myopia as SE between -3.00 and -6.00 D, and high myopia as SE worse than -6.00 D.
The study population was 51.7% women, 48.3% men, and 50% were younger than 25 years. The patients had moderate or high myopia and received MMC (43.3%), low myopia and received MMC (24.2%), or low myopia and did not receive MMC (32.5%).
Compared with baseline, following the T-PRK procedure all groups had significant decreases in sphere (range, -0.31 to -1.87; P =.000), cylinder (range, -0.64 to -2.62; P ≤.006), and spherical equivalent (range, -0.51 to -4.13; P =.000) parameters. The researchers noted the greatest changes among the moderate or high myopia MMC recipients and the most modest changes occurred among the low myopia MMC recipients.
Endothelial cell density and average cell area were unchanged from baseline among the low myopia without MMC and the moderate or high myopia with MMC groups but were significantly reduced among low myopia MMC recipients (both P ≤.005). The coefficient of variation was unaffected among the low myopia with or without MMC but was increased among the moderate or high myopia MMC recipients (P =.001).
Among all participants, the proportion of hexagonal-shaped endothelial cells and central corneal thickness decreased significantly from baseline to month three after T-PRK (all P ≤.013).
This study was limited by its retrospective, nonrandomized design.
“Generally, the incidence of corneal haze is common among high order refractive corrections due to deeper ablations. However, the T-PRK procedure itself reduces haze formation as it is gentle and aberration-free. Furthermore, the combined effect of MMC has resulted in significant prevention of corneal haze in 119 out of 120 eyes,” according to the researchers.
Al-Mohaimeed MM. Effect of prophylactic mitomycin c on corneal endothelium following transepithelial photorefractive keratectomy in myopic patients. Clin Ophthalmol. 2022;16:2813-2822. doi:10.2147/OPTH.S375587