Department of Ophthalmology and Optometry, Eye and ENT Hospital, Fudan University, 83 Fenyang Road, Shanghai, 200031, PR China.
NHC Key Laboratory of Myopia, Fudan University, Shanghai, China.
BMC Ophthalmol. 2022 May 28;22(1):239. doi: 10.1186/s12886-022-02463-2.
To study the 5-year changes in the posterior corneal surface after small incision lenticule extraction (SMILE) for high myopia.
Eighty eyes received SMILE was included in this prospective study. They were allocated into two groups based on the spherical equivalent: high myopia (40eyes, -7.49 ± 0.70D) and moderate myopia (40eyes, -4.43 ± 0.87D). Certain points of posterior corneal elevation (the central point (PCE), thinnest point (PTE), maximal point (PME), and in various corneal areas) were evaluated using a Scheimpflug camera (Pentacam; Oculus GmbH, Germany) preoperatively and at 6 months and 5 years after surgery.
All surgeries were completed uneventfully and no ectasia was developed throng the observation. The safety index and efficacy index were 1.14 and 1.03 in the high myopia group, and 1.16 and 1.06 in the moderate myopia group, respectively. Most of the calculated values in the high myopia group showed a slight increase at 6 months but decreased at 5 years. At 5 years postoperatively, the value of the PTE was significantly lower than at baseline in both groups (P ≤ 0.047); a statistical difference was also revealed in the PME in the moderate group with slight changes (10.15 ± 3.01 μm vs. 11.60 ± 4.33 μm, P = 0.002); no statistical significance was observed in other calculated values (P ≥ 0.067). Similarly, no significant linear correlation was noted between changes in all values and the residual bed thickness either (P ≥ 0.057).
SMILE causes no protrusion in posterior corneal surface for correction of high myopia at the follow-up visit of 5 years.
研究高度近视患者行小切口角膜基质透镜取出术（SMILE）后 5 年的后角膜表面变化。
本前瞻性研究纳入 80 只眼行 SMILE 手术。根据等效球镜度数将其分为两组：高度近视组（40 只眼，-7.49±0.70D）和中度近视组（40 只眼，-4.43±0.87D）。使用 Scheimpflug 相机（Pentacam；Oculus GmbH，德国）于术前及术后 6 个月和 5 年，评估后角膜抬高的某些点（中央点（PCE）、最薄点（PTE）、最大点（PME）和各个角膜区域）。
所有手术均顺利完成，观察期间未发生扩张。高度近视组的安全性指数和有效性指数分别为 1.14 和 1.03，中度近视组分别为 1.16 和 1.06。高度近视组大多数计算值在术后 6 个月略有增加，但在术后 5 年时下降。术后 5 年时，两组的 PTE 值均明显低于基线值（P≤0.047）；中度组的 PME 也有轻微变化，差异有统计学意义（10.15±3.01μm 比 11.60±4.33μm，P=0.002）；其他计算值无统计学意义（P≥0.067）。同样，所有值的变化与剩余床厚度之间也无明显线性相关性（P≥0.057）。
SMILE 治疗高度近视时，后角膜表面在 5 年随访中没有突出。
