Corneal Biomechanical Changes After Myopic Photorefractive Keratectomy

Purpose: To study the corneal biomechanical and morphological changes after photorefractive keratectomy (PRK) and the correlation with morphological parameters. Methods: 119 eyes of 75 subjects with a refraction ranging between -0.50 D and -14.50 D (mean=-4.7 +/- 2.3 D) were included in this study. The differences in corneal hysteresis (CH) and corneal resistance factor (CRF) one, three, and six months after PRK have been correlated with effective treatment, central corneal thickness (CCT), and corneal volume (CV) variations at any follow-up utilizing the Pearson Index. Differences between preoperative and postoperative values of the analyzed parameters have been checked with Student T test. Results: Both CH and CRF showed a significant (p<0.01) decrease at one, three, and six months' follow-up. Conclusion: Our findings suggest that after myopic PRK there is a significant decrease of CH and CRF immediately after treatment that remains stable over the follow-up.