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.
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).
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.
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.