目的:角膜帽厚度是小切口微透镜摘除(SMILE)中设计的重要参数。目的探讨角膜基底下神经丛(SNP)和不同帽厚度的基质细胞的变化,并评估手术的优化设计。
方法:在此前瞻性中,比较,非随机研究,54例接受SMILE手术的患者共108只眼被分为三组,不同角膜盖厚度(110μm,120μm或130μm组)。在1周时收集从体内角膜共聚焦显微镜(IVCCM)获得的SNP和基质细胞形态变化及其屈光结果,1个月,术后3个月和6个月。使用单因素方差分析(ANOVA)来比较三组之间的参数。
结果:三组患者术后SNPs均呈下降趋势,随访6个月呈逐渐升高趋势。110μm组的定量神经指标值明显低于120μm和130μm组,尤其是术后1周。在任何时间点,在120μm和130μm组之间没有检测到差异。手术后,朗格汉斯细胞和角膜细胞都被激活,并且在随访期间激活得到缓解。
结论:110μm的SMILE手术,120μm或130μm帽厚度设计取得了良好的效果,安全,中度至高度近视矫正的准确性和稳定性,而较厚的角膜帽更有利于角膜神经再生。
OBJECTIVE: The corneal cap thickness is a vital parameter designed in small incision lenticule extraction (SMILE). The purpose was to investigate the changes in corneal subbasal nerve plexus (SNP) and stromal cells with different cap thicknesses and evaluate the optimized design for the surgery.
METHODS: In this prospective, comparative, non-randomized study, a total of 108 eyes of 54 patients who underwent SMILE were allocated into three groups with different corneal cap thicknesses (110 μm, 120 μm or 130 μm group). The SNP and stromal cell morphological changes obtained from in vivo corneal confocal microscopy (IVCCM) along with their refractive outcomes were collected at 1 week, 1 month, 3 months and 6 months postoperatively. One-way analysis of variance (ANOVA) was used to compare the parameters among the three groups.
RESULTS: The SNPs in the three groups all decreased after surgery and revealed a gradual increasing trend during the 6-month follow-up. The values of the quantitative nerve metrics were significantly lower in the 110 μm group than in the 120 μm and 130 μm groups, especially at 1 week postoperatively. No difference was detected between the 120 μm and 130 μm groups at any time point. Both Langerhans cells and keratocytes were activated after surgery, and the activation was alleviated during the follow-up.
CONCLUSIONS: The SMILE surgeries with 110 μm, 120 μm or 130 μm cap thickness design achieved good efficacy, safety, accuracy and stability for moderate to high myopic correction while the thicker corneal cap was more beneficial for corneal nerve regeneration.