紫外线对LASEK术后早期角膜Haze的影响

目的　探讨紫外线暴露与ＬＡＳＥＫ术后早期角膜Ｈａｚｅ形成的关系。方法　选取２０１２年１月至２０１３年１２月在武汉大学人民医院接受ＬＡＳＥＫ的近视患者１９９例（３８９眼），按照患者接受手术的时间分为两组:一组接受手术的月份为紫外线强度较弱的１月、２月、１１月、１２月，为低紫外线暴露组；另一组接受手术的月份为紫外线强度较强的５月、６月、７月、８月，为高紫外线暴露组。比较两组术后早期（术后３个月内）角膜Ｈａｚｅ的发生情况。结果　两组一般资料比较，高紫外线暴露组的切削光学区（５．６±０．５）ｍｍ大于低紫外线暴露组（５．５±０．５）ｍｍ，差异有统计学意义（ｔ＝－２．２４４，Ｐ＝０．０２６），而两组性别、年龄、术前屈光度等效球镜、术前角膜中心厚度、切削深度、角膜切削率（术中角膜切削深度／术前角膜中心厚度）的差异均无统计学意义（均为Ｐ＞０．０５）。高紫外线暴露组术后角膜Ｈａｚｅ达到０级、０．５级、１级、２级的比例分别为７７．４％、１２．３％、６．３％、４．０％，低紫外线暴露组的比例分别为８６．９％、８．０％、４．４％、０．７％，差异有统计学意义（Ｚ＝ －２．３２５，Ｐ＝０．０２０），高紫外线暴露组患者的角膜Ｈａｚｅ较重。术后角膜Ｈａｚｅ达到２级的患者集中在高紫外线暴露组，手术月份集中在６月、７月、８月。结论　环境中的高紫外线辐射可能促进ＬＡＳＥＫ术后早期角膜Ｈａｚｅ的形成。

Effects of ultraviolet radiation on early corneal Haze after LASEK

Objective To investigate the correlation between the incidence of early corneal Haze after LASEK and ultraviolet radiation levels. Methods The study comprised 199 patients ( 389 eyes) who underwent LASEK surgery from January 2012 to December 2013 in Renmin Hospital of Wuhan University. The Patients were divided into two groups according to the months when they underwent LASEK surgery : a low ultraviolet radiation group which was treated on January , February , November and December. and a high ultraviolet radiation group which was treated on May , June ,July and August. The occurrence of the early corneal Haze after LASEK ( within 3 months) was compared between the two groups. Results The optical zone in the high ultraviolet radiation group was ( 5. 6 +0. 5 ) mm . which was statistically larger than that in the low ultraviolet radiation group ( 5. 5 + 0. 5 ) mm ( t = - 2. 244 ,P = 0. 026 ) .but the difference on gender , age , preoperative spherical equivalent . central corneal thickness , cutting depth , and cutting ratio between two groups was not statistically significant ( all P > 0. 05 ) . The proportions of eyes with early corneal Haze at grade 0.0. 5, I and 2 were 77. 4% . 12. 3% .6. 3% and 4. 0% respectively in the high ultraviolet radiation group , and the proportions were 86. g% ,8. 0% .4. 4% ,0. 7% respectively in the low ultraviolet radiation group , there was statistical difference ( z = - 2. 325 .P = 0. 020 ) . Most of the patients with corneal Haze of grade 2 were in the high ultraviolet radiation group and treated on June ,July and August. Conclusion High ultraviolet radiation in the environment may promote the formation of Haze in the early postoperative period of LASEK.