用Pentacam系统研究LASIK术后角膜后表面高度及曲率变化

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(LASIK)术后角膜后表面高度及曲率的变化,探讨准分子激光手术对角膜后表面高度及曲率变化的影响因素。方法对200例(398只眼)施行LASIK的完整患者资料进行回顾性分析,分别于术前及术后3个月应用Pentacam系统对患者的角膜后表面高度及曲率进行检查并分析。结果角膜后表面高度变化在轻度近视组、中度近视组及高度近视组各组间比较差异具有统计学意义(P<0.05);后表面曲率变化在轻度近视组与中度近视组、高度近视组间比较差异均具有统计学意义(P<0.05),而中度近视组、高度近视组间比较差异无统计学意义(P>0.05)。角膜后表面高度及曲率变化在角膜床厚度250～280μm组与281～320μm组间、250～280μm组与>320μm组间比较差异具有统计学意义,在281～320μm组与>320μm组间比较差异无统计学意义(P>0.05)。结论 LASIK术后角膜后表面向前突,后表面高度增加,曲率负值增加,术前等效球镜越小、角膜床厚度越厚,角膜后表面高度及曲率变化越小。

Corneal posterior elevation and back sagittal curvature measured by Pentacam after LASIK

Objective To analyze the influence of LASIK（laser in situkeratomileusis） on the change of corneal posterior elevation and corneal back sagittal curvature using Pentacam.Methods Two hundred patients（398 eyes）were retrospective reviewed.corneal posterior elevation corneal back sagittal curvature were examed by Pentacam before and three months later after LASIK operation.Results The difference of corneal back elevation and corneal back sagittal curvature among mild myopia group,moderate myopia group,and high myopia group is significant（P0.05;however,the difference of corneal back elevation and corneal back sagittal curvature between moderate myopia and high myopia is not significant（P0.05）.The variation on corneal back elevation and corneal back sagittal curvature between corneal bed thickness 250~280 μm group and 281~320 μm group has Statistical significance,and between 250~280 μm group and 320 μm group.But the variation between 281~320 μm group and320 μm group has no statistical significance（P0.05）.Conclusion After LASIK,the corneal backside will be moved forward,the corneal back elevation increases,and negative curvature increases.The smaller the preoperative spherical equivalent,the thicker corneal bed thickness,the slighter change on corneal back elevation and corneal back sagittal curvature.