Visumax飞秒激光辅助LASIK的新型制瓣模式对不透明气泡层发生的影响

目的：探究Visumax飞秒激光辅助准分子激光原位角膜磨镶术（LASIK）的新型制瓣模式对术中不透 明气泡层（OBL）产生的影响,分析影响OBL发生的相关因素。方法：病例对照研究。收集2020年4—8 月于首都医科大学附属北京同仁医院屈光手术中心行飞秒激光辅助制瓣的LASIK者72例（128眼）的 术前病历资料及手术设计参数,通过手术录像确定制瓣过程是否产生OBL及其分型。根据制瓣方 式不同将术眼分为传统制瓣组64眼（38例）和新型制瓣组（采用新型制瓣模式）64眼（34例）。采用卡 方检验对2组间OBL发生率及OBL各类型发生率的差异进行分析。采用单因素和Logistic回归分析 OBL产生的相关影响因素。结果：传统制瓣组与新型制瓣组间年龄及眼部相关参数差异均无统计学 意义。传统制瓣组OBL发生率明显高于新型制瓣组（44% vs. 16%,χ2 =12.13,P<0.001）。传统制瓣组 硬型OBL发生率明显高于新型制瓣组（28% vs. 0%,χ2 =12.21,P<0.001）。传统制瓣组单因素分析中 得到角膜瓣厚度与角膜厚度的比值较小为OBL发生的危险因素（Z=-1.04, P=0.030）。新型制瓣组单 因素分析中发现较高的近视度数（Z=-2.33, P=0.020）及较小的角膜直径（Z=-2.64, P=0.010）为OBL 发生的危险因素。Logistic回归得到角膜直径增加可降低OBL发生风险（OR=0.05,95％CI：0.03~0.65, P=0.023）。结论：Visumax飞秒激光辅助LASIK的新型制瓣模式有助于减少OBL发生,角膜瓣厚度 与角膜厚度比值较小及角膜直径较小者更易产生OBL。

Effect of a New Flap-Making Mode with Visumax Femtosecond LaserAssisted LASIK on the Formation of an Opaque Bubble Layer

Objective: To investigate if a new flap-making pattern of Visumax femtosecond laser-assisted laser in situ keratiomileusis (LASIK) could impact the occurrence of an opaque bubble layer (OBL), and to analyze related factors affecting the formation of an OBL. Methods: This was a case-control study. The preoperative medical records and surgical design parameters of 72 patients (128 eyes) who underwent FS-LASIK in the Refractive Surgery Center of the Beijing Tongren Hospital, Capital Medical University, from April to August 2020 were collected. The OBL and its classification were determined by the operation video. The operative eyes were divided into two groups based on the different patterns of flap-making. There were 64 eyes each in the traditional (38 patients) and new pattern (34 patients) groups, of which a new pattern was adopted for the latter group. The baseline data of the two groups were compared, and the incidence of overall OBLs and OBL types in the two groups were counted. A Chi-square test was used to analyze whether there was any difference. In addition, univariate analysis was performed for the two groups, and significance parameters were incorporated into a logistic regression to further analyze the related influencing factors of OBL. Results: Baseline data was balanced between the two groups. The incidence of OBL in the traditional group was significantly higher than that in the new group (44% vs. 16%, χ2 =12.13, P<0.001), and the incidence of hard OBL in the traditional group was significantly higher than that in the new group (28% vs. 0%, χ2 =12.21, P<0.001). Univariate analysis showed a smaller flap thickness to central corneal thickness ratio in the traditional flap-making group (Z=-1.04, P=0.030), while a higher degree of myopia (Z=-2.33, P=0.020) and smaller corneal diameter (Z=-2.64, P=0.010) ratio were risk factors for OBL in the new flap-making group. Logistic regression showed that an increased corneal diameter could reduce the risk of OBL (OR=0.05, 95%CI: 0.03-0.65, P=0.023). Conclusion: A new flap-making pattern with Visumax femtosecond laser-assisted LASIK can reduce the occurrence of an OBL. It is more likely to occur in patients with a smaller flap thickness to central corneal thickness ratio and a smaller corneal diameter