SMILE矫正高度近视的临床疗效及角膜后表面高度改变

Clinical Efficacy and Posterior Corneal Elevation of Small Incision Lenticule Extraction in High Myopes

目的:观察小切口角膜基质透镜取出术(SMILE)矫正高度近视的安全性、有效性、可预测性、稳定性及角膜后表面高度的变化情况。方法:描述性纵向研究。对2016年中南大学湘雅医院眼科37例高度近视SMILE术后患者67眼(等效球镜度为-10.75^-6.25D)做回顾性分析,于术前、术后1d、1个月、3个月、6个月行裸眼视力(UCVA)、最佳矫正视力(BCVA)、屈光度、眼压、眼轴、角膜地形图等检查。采用广义估计方程对手术前后数据及影响因素进行分析。结果:高度近视患者SMILE术后6个月UCVA(LogMAR)为-0.1(-0.2,0),有效性指数0.83±0.20;BCVA(LogMAR)-0.2(-0.2,-0.2),安全性指数1.03±0.16。术后1、3、6个月近视度数逐渐增加,术后6个月屈光度为-0.25(-0.50,0)D,回退量为-0.25(-0.50,0)D。术后UCVA(LogMAR)与年龄呈正相关,术后屈光度、回退量均与年龄呈负相关。角膜后表面Diff值术前为(0.030±0.006)mm,术后6个月为(0.046±0.012)mm,较术后1个月降低,与术后3个月差异无统计学意义。术后6个月Diff值及ΔDiff值均与角膜组织改变百分比mPTA呈正相关。结论:SMILE矫正高度近视有较好的安全性、有效性、可预测性和稳定性,但在术后6个月内仍有轻度屈光度回退,尤其是年龄较大的患者。术后角膜后表面前移,术后3个月部分恢复,术中组织切削百分比较大者前移量较大。

Objective: To investigate the safety, efficacy, predictability, stability and posterior corneal elevation of small incision lenticule extraction (SMILE) for high myopia. Methods: This study was a descriptive longitudinal study. A retrospective analysis was performed on 37 patients (67 eyes) with high myopia (spherical equivalent,-10.75--6.25 D) who underwent SMILE in the Ophthalmology Department of Xiangya Hospital, Central South University in 2016. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refractive error, intraocular pressure (IOP), axial length, and corneal topography were measured preoperatively and postoperatively at 1 day, 1 month, 3 months and 6 months. The data before and after surgery and the influencing factors were analyzed by a generalized estimation equation.Results: The UCVA (LogMAR) of the high myopes was -0.1 (-0.2, 0), the effective index was 0.83±0.20, the BCVA (LogMAR) was -0.2 (-0.2,-0.2), and the safety index was 1.03±0.16 at 6 months after SMILE. The degree of myopia increased gradually from 1 month to 6 months postoperatively. The refractive error was -0.25 (-0.50, 0) D and regression was -0.25 (-0.50, 0) D at 6 months after SMILE. UCVA was positively correlated with age, refractive error and regression and was negatively correlated with age after surgery. The difference value of the posterior corneal surface was 0.030±0.006 mm before and 0.046± 0.012 mm 6 months after surgery, which was lower than that in the first month, and was not statistically different at 3 months. Difference and Δdifference at 6 months were positively correlated with mPTA (modified percent tissue altered). Conclusions: This study demonstrates SMILE to be a safe, effective, predictable and stable procedure for the treatment of high myopia, with a slight myopic regression at 6 months after surgery, especially in elders. The posterior corneal surface shifts forward postoperatively and partially recovers after 3 months;the amounts are associated with mPTA.