Iu Lawrence P L, Fan Michelle C Y, Chen Ivan N, Lai Jimmy S M
Department of Ophthalmology, The University of Hong Kong, Grantham Hospital Department of Ophthalmology, Hong Kong Sanatorium and Hospital, Hong Kong.
Medicine (Baltimore). 2017 Jun;96(22):e7076. doi: 10.1097/MD.0000000000007076.
The purpose of this study was to evaluate the predictability and stability of laser-assisted subepithelial keratectomy (LASEK) with mitomycin C (MMC) in correction of high myopia (≤-6.0 diopters [D]) as compared to low-to-moderate myopia (>-6.0 D).This is a retrospective, comparative, cohort study which included 43 eyes of 43 consecutive patients who underwent LASEK with MMC in a private hospital in Hong Kong by a single surgeon. Twenty-five eyes had high myopia (mean spherical equivalent [SE] = -8.53 ± 1.82 D) and 18 eyes had low-to-moderate myopia (mean SE = -3.99 ± 1.37 D) before surgery.In terms of refractive predictability, mean SE was significantly better in eyes with preoperative low-to-moderate myopia than high myopia at 6 months (0.04 ± 0.23 vs 0.31 ± 0.52 D, P = .035). In terms of refractive stability, between 1 and 3 months, both groups had mean absolute change of SE of around 0.25 D. Between 3 and 6 months, preoperative low-to-moderate myopia group had significantly less absolute change of SE compared to high myopia group (0.07 vs 0.23 D, P = .003). More eyes with preoperative high myopia changed SE by more than 0.25 D than those with low-to-moderate myopia between 3 and 6 months (32.0% vs 5.6%, P = .057).In conclusion, LASEK with MMC is more unpredictable and unstable in correction of high myopia than low-to-moderate myopia. The refractive outcome of most low-to-moderate myopia correction stabilizes at 3 months. Stability is not achieved until after 6 months in high myopia correction.
本研究的目的是评估与中低度近视（>-6.0屈光度[D]）相比，使用丝裂霉素C（MMC）的准分子激光上皮下角膜磨镶术（LASEK）矫正高度近视（≤-6.0屈光度[D]）的可预测性和稳定性。这是一项回顾性、比较性队列研究，纳入了香港一家私立医院中由同一位外科医生为43例连续患者实施的43只接受MMC-LASEK手术的眼睛。术前，25只眼睛为高度近视（平均等效球镜度[SE]=-8.53±1.82D），18只眼睛为中低度近视（平均SE=-3.99±1.37D）。在屈光可预测性方面，术前中低度近视眼睛在术后6个月时的平均SE显著优于高度近视眼睛（0.04±0.23 vs 0.31±0.52D，P=0.035）。在屈光稳定性方面，术后1至3个月，两组的SE平均绝对变化约为0.25D。术后3至6个月，术前中低度近视组的SE绝对变化显著低于高度近视组（0.07 vs 0.23D，P=0.003）。术后3至6个月，术前高度近视眼睛中SE变化超过0.25D的眼睛比中低度近视眼睛更多（32.0% vs 5.6%，P=0.057）。总之，与中低度近视相比，使用MMC的LASEK矫正高度近视时的可预测性和稳定性较差。大多数中低度近视矫正的屈光结果在术后3个月时趋于稳定。高度近视矫正术后6个月后才实现稳定性。
