Changes in Central Corneal Thickness After Laser in situ Keratomileusis and Photorefractive Keratectomy

Abstract

PURPOSE: To evaluate changes in corneal thickness after laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) in eyes with the same preoperative refraction, correlate these changes to postoperative refractive outcomes, and compare corneal healing process in a standardized subset of patients. METHODS: Central corneal thickness was measured by contact ultrasound pachymetry in 14 eyes of 8 patients with preoperative myopia of -6.00 D who had LASIK, and in 14 eyes of 8 patients with the same preoperative refractive error who had PRK. Measurements were taken preoperatively, and 1 week, 3, and 6 months after surgery. Data were evaluated and compared using the paired Student i-test and Pearson correlation coefficient. RESULTS: Mean preoperative central corneal thickness in the LASIK group was 549.14 ± 37.4 µ?\, and in the PRK group, 552.64 ± 34.9 µp?. At 1-week postoperatively, mean central corneal thickness in the LASIK eyes was 467.28 ± 29 /tra and in the PRK eyes, 473.85 ± 39.2 µ??; at 6 months, central corneal thickness had increased in both groups compared to the 1-week values; LASIK eyes had a mean central corneal thickness of 481.42 ± 23.0 µ?a and PRK, 481.50 ± 35.3 µta. Mean postoperative refraction after 6 months was -0.48 ± 0.30 D in the LASIK group and -0.67 ± 0.35 D in the PRK group. CONCLUSION: Increase in central corneal thickness between 1 week and 6 months postoperatively occurred in both LASLK and PRK eyes, but differences were not statistically significant. No statistically significant differences were found in myopic regression between the two patient groups. [J Refract Surg 2003;19:149-153]

Unexpected ocular morphological changes after corneal refractive surgery: A review

“…Thanks to its reliability and effectiveness, today it is considered a worldwide diffuse and accepted method (3)(4)(5)(6)(7). It is well-known that the refractive effect is related to the corneal flattening and thinning, and several authors evaluated these induced changes (8)(9)(10)(11).…”

Distribution Pattern of Total Corneal Thickness in Keratoconus Versus Normal Eyes Using An Optical Coherence Tomography

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