The Impact of Ethyle Alcohol Contact Time on Corneal Epithelial Healing in Cases of Photorefractive Keratectomy

The study was carried out on 70 patients who were candidates for laser corneal refractive surgery with alcohol-assisted PRK. The study comprised two groups. Group 1 included the right eye of the patients, and Group 2 included the left eye of the same patients. Group 1 was operated with PRK with alcohol 20% applied for 15 seconds, while group 2 underwent PRK with alcohol 20% applied for 30 seconds. Mitomycin C (MMC) 0.02% was applied for 30 seconds after the laser ablation in both groups.

Inclusions criteria:

The included patients should meet the following criteria: age between 18 and 35 years, both genders, with normal corneal topography, clear cornea, and stable refractive error for at least 12 months before the surgery. Both eyes should have low to moderate myopia with spherical error of more than -4D spherical error, cylindrical error of more than -1.5D, and an estimated stromal ablation depth of less than 70 µm.

Exclusion criteria:

The patients were excluded from the study if they had one or more of the following findings: patients with mixed astigmatism in either eye, contact lens wearers, abnormal corneal topography, thin cornea less than 500 microns, corneal opacity, dry eye disease, history of herpetic keratitis, corneal epithelial pathology (dystrophies or scarring), atopy, collagen diseases, autoimmune disease, systemic diseases that interfere with healing (e.g. diabetes mellitus), eyelid diseases, ocular pathology, previous history of refractive or corneal surgery, and pregnant or lactating females. Also, patients who failed to attend the follow-up visits were excluded.