Corneal epithelial wound healing after excimer laser photorefractive and photoastigmatic keratectomy (PRK and PARK)

Purpose. This study compared the duration of corneal reepithelialization be tween photorefractive (PRK) and photoastigmatic (PARK) keratectomy and eval uated the possible correlation of the epithelial healing rate with clinical parameters as well as the refractive outcome. Methods. The duration until complete reepithelialization was examined in 33 eyes of 33 patients (14 men ), not suffering from any known disease, who underwent PRK or PARK surgery. In all cases, a +0.5 diopters (D) therapeutic contact lens (Acuvue Vistako n) was used postoperatively. Clinical parameters such as age, sex, preopera tive spherical equivalent, attempted correction, corneal curvature, and sur gical plan were recorded in the patient file. All patients received standar d medication and were followed up for 12 months postoperatively. Results we re statistically analyzed by using the package SPSS 6.0. Results. The durat ion of reepithelialization was significantly correlated to age and was long er in PARK than in PRK cases and in eyes with an average K reading >43.5D. A shorter reepithelialization period correlated to myopic regression, 1 mon th postoperatively, but the correlation was annulled thereafter. Conclusion . The longer reepithelialization period in older patients and in PARK surge ry could be attributed to the age-related decrease in the healing response and to differences in the profile of the ablation area, respectively. Epith elial healing was shorter in eyes with steeper K readings, perhaps because of better contact lens mobility. Understanding the role of factors involved in epithelial healing could allow better postoperative surveillance and tr eatment.