Long-term Follow-up of LASEK With Mitomycin C Performed to Correct Myopia in Thin Corneas.

Abstract

To evaluate the long-term outcomes of laser-assisted subepithelial keratomileusis (LASEK) with intraoperative use of mitomycin C (MMC) performed on thin corneas for the correction of myopia. This retrospective cohort study included 100 eyes with a preoperative central corneal thickness (CCT) thinner than 500 μm that underwent LASEK + MMC with at least 6 years of follow-up. Stability of visual acuity and refraction and the efficacy, safety, and predictability at the examinations 3 months and the last annual postoperative visit were analyzed. Preoperative CCT was 482.9 ± 14.7 μm (range: 433 to 499 μm). Mean preoperative spherical equivalent was -4.09 ± 2.3 diopters (D). At the 3-month postoperative visit, mean CCT was 419.79 ± 32.6 μm. The residual spherical equivalent showed a statistically significant regression (P = .001) in the comparison between the 3-month and the last annual postoperative visit. The efficacy index showed a significant decrease (P = .01) and the safety index remained stable around 0.96. Six or more years after the surgery, 85 eyes (85%) were within ±0.50 D and 94 eyes (94%) eyes were within ±1.00 D of emmetropia. The topography did not show signs of secondary corneal ectasia in any eye. LASEK with intraoperative use of MMC seems to be safe, effective, and predictable to correct myopia in corneas thinner than 500 μm and with normal preoperative topography, providing good visual and refractive outcomes with no topographic signs of corneal ectasia in a mean 6.5-year follow-up. [J Refract Surg. 2017;33(12):813-819.].