方法：回顾性病例分析。收集我院2016-01/2017-12行Trans-PRK手术治疗的高度近视患者89例142眼，其中94眼联合使用0.02% MMC设为MMC组，MMC的使用时间为30～45s； 48眼未使用MMC设为对照组。两组患者术后均规律使用类固醇激素滴眼液治疗4mo，随访6mo。采用树模型分析探讨不同相关因素与haze发生的相关性。

结果：按照Fantes分级进行haze评估。MMC组术后haze发生率为8.5%(8/94)，对照组为33.3%(16/48)(P=0.001)。树模型结果显示，切削光区直径和切削深度是haze发生的主要相关因素(P<0.01)。当切削光区直径≤5.6mm时发生haze的可能性越大，当切削光区直径>5.6mm时，最大切削深度成为haze发生的主要影响因素。

结论：对于薄角膜及角膜形态异常的高度近视患者，在选择Trans-PRK治疗时应考虑切削光区直径及切削深度，同时应联合使用0.02% MMC，可以安全有效地减少haze发生。

METHODS: Retrospective case series. Trans-PRK were performed on 142 eyes with a preoperative spherical equivalent. They were divided into with 0.02% MMC(MMC group)and without MMC(control)groups. In MMC group there were 94 eyes with MMC 0.02%; in control group there were 48 eyes. Patients were treated with an intraoperative application of MMC 0.02% for 30-45s depending on refractive error in MMC group. After surgery, fluorometholone 0.1% eye drops were used for 4mo in all groups. The mean follow-up time was 6mo. The regression trees were used to analyse the relationship between different related factors and haze.

RESULTS:Haze was quantified with Fantes. Incidence of haze was 8.5% eyes in MMC group and 33.3% in without MMC group(P=0.001). In the regression trees, optical zone and ablation depth MAX were related to haze(P<0.01). It was possibility induce haze when optical zone is ≤5.6mm. When optical zone is >5.6mm, ablation depth MAX becomes the main factor for haze.

CONCLUSION: The design of optical zone and ablation depth MAX in Trans-PRK should be considered for the treatment of the high myopia with thin cornea and abnormal corneal morphology. MMC 0.02% was effective in preventing haze after Trans-PRK in the treatment of the high myopia.