Noncontact thermokeratoplasty to correct hyperopia induced by laser in situ keratomileusis.

摘要

PURPOSE: To evaluate the efficacy and safety of noncontact holmium:YAG (Ho:YAG) laser thermokeratoplasty (LTK) for treating hyperopia induced by laser in situ keratomileusis (LASIK). SETTING: Department of Ophthalmology, University of Alicante, Instituto Oftalmologico de Alicante, Alicante, Spain, and the University of Al-Azhar, Cairo, Egypt. METHODS: Noncontact LTK was applied to 13 eyes (11 patients) with significant hyperopia after LASIK using a Ho:YAG laser (model gLase 210, Sunrise Technologies). Mean spherical equivalent before LTK was +4.60 diopters (D) +/- 1.40 (SD) (range +2.50 to +7.25 D). The results were evaluated 18 months after the LTK surgery. RESULTS: A significant myopic shift developed in all eyes that gradually receded to emmetropia 6 to 8 weeks after LTK. After 12 months, refraction was relatively stable. At 18 months, there was a statistically significant difference between the mean uncorrected visual acuity (UCVA) before LTK (0.19 +/- 0.09) and mean postoperative UCVA (0.61 +/- 0.22) (P < .005). At the end of the study, there was a mean increase of 4.10 +/- 1.12 D in central keratometric power. Total regression did not occur in any eye. CONCLUSION: Noncontact Ho:YAG LTK was safe and effective in correcting LASIK-induced hyperopia. The cutting of Bowman's layer and a thinner corneal center may contribute to the stability of LTK in such cases.