Purpose: To compare the achieved corneal pachymetry (AP) with the expected one (EP) after 3 months of LASIK for myopia. Methods: 77 myopic eyes of 39 patients were included in this study. Surgery was performed with the Technolas 217 excimer laser and the Chiron automated corneal shaper microkeratome. Screening pachymetry was performed in all corneas before and 3 months after LASIK. EP was obtained by subtracting the ablation depth from the preoperative pachymetry. Patients were divided into 3 groups as follows: Group A (55 eyes), from -1.00 diopter (D) to -5.75D; group B (14 eyes), from -6.00D to -10.00D and group C (8 eyes), more than -10.00D. Results: The mean spherical equivalent decreased from -2.17D to 0.00 in group A, -8.18D to 0.00 in group B and -11.4D to -1.06D in group C. Mean AP was 491 mum in group A, 431 mum in group B and 427 mum in group C. In 70 eyes (90.9%) AP was superior to EP with a statistically significant difference (p=0.001). Conclusions: Although these data showed a corneal thickness greater than that expected after LASIK, undercorrection was not significant. After 3 months, most of patients have a refraction near emmetropia.
Myopia; Photorefractive keratectomy excimer laser; Cornea; Ocular refraction
