A comparison of postoperative efficacy and safety between laser-assisted subepithelial keratomileusis versus femtosecond laser assisted in situ keratomileusis for high myopic eyes / 中华实验眼科杂志

ABSTRACT

Objective:To evaluate and compare the safety, efficacy, stability and predictability of laser-assisted subepithelial keratomileusis (LASEK) with femtosecond laser assisted in situ keratomileusis (FS-LASIK) for high myopic eyes.Methods:A non-randomized controlled clinical study was performed.The clinical data of 141 eyes of 75 patients who received LASEK or FS-LASIK for high myopia in Shandong Eye Hospital from January 2013 to December 2016 with complete medical data during 1-year following-up.The 56 eyes with the preoperative diopter of (-8.29±1.64)D received LASEK (LASEK group), and the 85 eyes with the preoperative diopter (-7.97±1.38)D underwent FS-LASIK (FS-LASIK group). Pre- and post-operative best corrected visual acuity (BCVA) and post-operative uncorrected visual acuity (UCVA) were recorded, and the spherical equivalent was examined by subjective optometry.The efficacy index, safety index, refractive stability, predictability and complications were assessed 6 months and 12 months after surgery.Efficacy index was defined as postoperative UCVA/preoperative BCVA; safety index was postoperative BCVA/preoperative BCVA; refractive stability was the difference of spherical equivalent between postoperative 6 months and 12 months, and predictability was the percentage of the eyes with the diopter ≤±0.50 D after surgery.This study protocol was approved by the Ethic Committee of Shandong Eye Hospital (No.SDSYKYY20180130).Results:There were no significant differences in efficacy index and safety index in both LASEK group and FS-LASIK group at 6 months and 12 months after surgery (all at P>0.05). The spherical equivalent was (0.08±0.30)D and (0.10±0.38)D in the LASEK group and (0.00±0.32)D and (0.01±0.35)D in the FS-LASIK group at 6 months and 12 months after surgery, and there were no significant differences between different time points in both LASEK group and FS-LASIK group ( t=0.376, P>0.05; t=0.227, P>0.05), showing a good refractive stability.At 12 months after surgery, the percentage of the eyes with spherical equivalent within ±0.50 D was 91.1% in the LASEK group and 96.4% in the FS-LASIK group, there was no significant difference between the two groups ( χ2=1.838, P>0.05). Four eyes in the LASEK group developed corneal haze at 12 months after the operation, and the postoperative BCVA was less than the preoperative BCVA. Conclusions:Both LASEK and FS-LASIK are safe, effective, stable and predictable for the correction of high myopic eyes.Corneal haze after LASEK is the main reason for the loss of BCVA.