Long‑Term Visual and Refractive Stability and Ocular Biometric Changes after Laser‑Assisted Subepithelial Keratomileusis for Correction of Myopia: An 8‑Year Follow‑Up

Purpose: To assess the long‑term visual and refractive stability and ocular biometric changes in low to moderate myopic subjects treated by laser‑assisted subepithelial keratomileusis (LASEK). Methods: It is a prospective, interventional study. Included were 70 eyes of 35 patients who underwent LASEK for correction of ≤6 diopters (D) myopia. The uncorrected and corrected distance visual acuity (UDVA and CDVA), manifest refractions, and ocular biometric indices (by Lenstar‑LS900, Haag‑Streit AG, Koeniz, Switzerland) including keratometry, anterior chamber depth (ACD), aqueous depth (AD), axial length (AL), central corneal thickness (CCT), and lens thickness (LT) were assessed preoperatively and after 6 months and 8 years. Results: Mean preoperative spherical equivalent was −3.99 (standard deviation [SD] =1.38) D which improved to 0.02 (SD = 0.27, P < 0.001) D and −0.10 (SD = 0.31, P < 0.001) D at 6 months and 8 years, respectively. The preoperative AL was not different from postoperative measures at 6 months (P = 0.15) and 8 years (P = 0.47). The ACD and AD decreased during 8 years, while LT increased (all P ≤ 0.001). The changes of LT inversely correlated with changes of ACD (rs = −0.67, P = 0.001 at 6 months and rs = −0.87, P < 0.001 at 8 years) and AD (rs = −0.76, P < 0.001 at 6 months and rs = −0.86, P < 0.001 at 8 years). The CCT and keratometry values reduced at 6 months postoperatively (all P < 0.001) and then did not change up to 8 years (0.21 ≤ P ≤ 0.87). Conclusions: The post‑LASEK myopic regression is 0.1 D over 8 years. Ocular biometric values like keratometry, CCT, ACD, AD, and LT have been changed for a long period after LASEK in low to moderate myopia except AL.