LASIK和LASEK术后角膜后表面高度和前房变化的临床研究

Clinical study of the changes in the posterior corneal elevation and anterior chamber of the eyes after LASIK and LASEK

目的应用Pentacam眼前节分析系统研究准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)和准分子激光上皮下角膜磨镶术(laser subepithelial keratomileusis,LASEK)术后角膜后表面高度、前房深度的变化,探讨准分子激光手术对眼前段结构变化的影响。方法对69例(138眼)施行LASIK或LASEK手术的患者资料进行回顾性分析,分别于术前,术后1个月、3个月应用Pentacam眼前节分析系统检测角膜厚度、角膜后表面高度、前房深度的变化。结果 LASIK、LASEK术后1个月、3个月角膜后表面高度均略微增高,LASIK术后1个月与3个月的前凸量分别为(1.89±3.24)μm与(1.18±2.33)μm,LASEK术后1个月与3个月的前凸量分别为(1.07±2.27)μm与(1.12±2.05)μm;术中切削比例对后表面高度的变化影响达到66.18%,术前屈光度对后表面高度的变化影响达到29.31%;LASIK术前、术后1个月和术后3个月前房深度分别为(3.24±0.27)mm、(3.18±0.26)mm和(3.18±0.27)mm;LASEK术前、术后1个月和术后3个月前房深度分别为(3.20±0.27)mm、(3.16±0.26)mm和(3.15±0.27)mm;LASIK、LASEK术后1个月、3个月前房深度变浅。结论 LASIK、LASEK术后均表现为角膜后表面微量前移,LASEK术后角膜后表面高度变化较LASIK更小;切削比例是影响角膜后表面变化最大的因素,两种手术方式术后前房变浅。

Objective To investigate the postoperative changes in the parameters of posterior corneal elevation,anterior chamber depth after laser in situ keratomileusis（LASIK） and laser subepithelial keratomileusis（LASEK） with the application of Pentacam system and accordingly to further analyze the influences of LASIK and LASEK on the anterior segment of the eye.Methods A retrospective anaysis was conducted on 69 patients（138 eyes） of LASIK and LASEK by randomized sampling.The changes in parameters in corneal thickness,posterior corneal elevation,central anterior chamber depth were analyzed with the Pentacam system preoperatively,1 month and 3 months postoperatively.Results Posterior corneal elevation slightly increased one and three months after LASIK and LASEK operations.The forward shift of posterior corneal surface after LASIK surgery were（1.89±3.24） μm and（1.18±2.33） μm at one month and three month respectively and the according values were（1.07±2.27） μm and（1.12±2.05） μm after LASEK.Posterior corneal elevation variations were influenced for 66.18% and 29.31% by cutting proportions and refractive error respectively.The anterior chamber depths were（3.24±0.27） mm pre LASIK,（3.18±0.26） mm one month after LASIK and（3.18±0.27） mm three months postoperatively.The corresponding values for surgery LASEK were（3.20±0.27） mm,（3.16±0.26） mm and（3.15±0.27） mm.The anterior chamber depth became slightly thinner.Conclusions Corneal posterior surface moves slightly forward in both LASIK and LASEK,with smaller variations in posterior corneal elevation for LASEK.Corneal posterior surface is most influenced by cutting proportions while anterior chamber depth becomes thinner after either LASIK or LASEK.