高度近视眼3种角膜屈光手术后角膜神经修复情况及角膜光密度的对比研究

Corneal nerve repair and optical density in patients with high myopia after three kinds of corneal refractive surgery

目的探讨高度近视眼行飞秒激光小切口角膜基质透镜取出术(SMILE)、飞秒激光制瓣的准分子激光原位角膜磨镶术(FS-LASIK)及准分子激光上皮瓣下角膜磨镶术(LASEK)术后12个月角膜不同区域上皮下神经的修复情况和角膜透明度的差异。方法队列研究。收集于2018年6月至2019年10月在山东省青岛大学附属医院眼科就诊并进行角膜屈光手术的高度近视眼(近视等效球镜度数6.00~10.00 D)患者30例(60只眼),其中女性16例(32只眼),男性14例(28只眼);年龄(22.46±3.15)岁,按手术方式分为SMILE组(10例)、FS-LASIK组(11例)、LASEK组(9例),于术后12个月在激光共聚焦显微镜下观察角膜不同区域上皮下神经的修复情况,并通过ACCMetrics软件分析其形态学参数,包括神经纤维密度(CNFD)、主要神经分叉节点密度(CNBD)、神经纤维长度(CNFL)、总神经分叉节点密度(CTBD)和神经纤维宽度(CNFW);采用Pentacam眼前节分析仪对角膜不同直径范围内的光密度进行检测。各组间神经形态学参数、角膜光密度的比较采用随机区组方差分析,组间多重比较采用Turkey真实显著差(HSD)检验。结果术后12个月,3种术式角膜各区域内的CNFD差异均无统计学意义(P>0.05)。SMILE组、FS-LASIK组及LASEK组上方角膜切口周围的CNBD分别为(7.81±7.93)、(9.61±7.18)、(21.25±15.55)个/mm^(2);CTBD分别为(22.00±16.02)、(24.44±11.42)、(54.37±22.13)个/mm^(2),LASEK组与其他两组相比,差异均有统计学意义(HSD=2.823,-3.010,3.053,-3.048;P<0.01);3个组CNFL分别为(9.19±3.25)、(12.88±3.52)、(15.75±2.36)mm/mm^(2),SMILE组与其他两组相比,差异有统计学意义(HSD=-3.151,-4.418;P<0.01)。SMILE术后直径12 mm内角膜的光密度为14.06±1.36,低于其他2种术式(HSD=-6.031,-5.519;P<0.01)。结论高度近视眼行SMILE术后12个月,角膜上方切口周围的神经修复情况略差于FS-LASIK和LASEK,但其他区域的神经修复情况存在一定的优势;SMILE术后角膜透明度更佳。

Objective To investigate the repair of subepithelial nerve fibers in different areas of the cornea and the difference of corneal transparency 12 months after small incision lenticule extraction(SMILE),femtosecond laser in situ keratomileusis(FS-LASIK)and excimer laser in situ keratomileusis(LASEK)in high myopia.Methods A cohort study.From June 2018 to October 2019,30 patients with high myopia(60 eyes)were selected for corneal refractive surgery in the Department of Ophthalmology,Affiliated Hospital of Qingdao University,including 16 females(32 eyes)and 14 males(28 eyes).According to the mode of operation,the patients were divided into the SMILE group(n=10),FS-LASIK group(n=11)and LASEK group(n=9).The repair of subepithelial nerves in different areas of the cornea was observed by laser confocal microscopy 12 months after operation,and the morphological parameters were analyzed by ACCMetrics software.The parameters included corneal nerve fiber density(CNFD),corneal nerve branch density(CNBD),corneal nerve fiber length(CNFL),corneal nerve fiber total branch density(CTBD)and corneal nerve fiber width.The Pentacam anterior segment analyzer was used to measure the optical density of the cornea in different diameters.The nerve fiber parameters and corneal optical density were compared by random block analysis of variance,and multiple comparisons were performed between groups by the Turkey test.Results Twelve months after operation,there was no significant difference in the CNFD among the three groups(all P>0.05).The CNBD around the upper corneal incision in the SMILE group,FS-LASIK group and LASEK group was(7.81±7.93),(9.61±7.18)and(21.25±15.55)branches/mm^(2),respectively.The CTBD was(22.00±16.02),(24.44±11.42)and(54.37±22.13)branches/mm^(2),respectively.The values in the LASEK group significantly differed from the other two groups(HSD=2.823,-3.010,3.053,-3.048,P<0.01).The CNFL was(9.19±3.25),(12.88±3.52)and(15.75±2.36)mm/mm^(2),respectively.The value in the SMILE group was significantly different(HSD=-3.151,-4.418;P<0.0l).The corneal optical density after SMILE was 13.16±0.72 in the 0-6 mm diameter area(HSD=-4.164,-4.489;P<0.01),16.12±3.18 in the 6-12 mm diameter area(HSD=-3.918,-3.493;P<0.01)and 14.06±1.36 in the total diameter(HSD=-6.031,-5.519;P<0.01),which differed significantly from the other two groups.Conclusions Twelve months after SMILE for high myopia,the nerve repair around the superior corneal incision is slightly worse than that after FS-LASIK and LASEK,but the nerve repair in other areas has some advantages,and the corneal transparency is better.