飞秒激光辅助LASIK治疗高角膜前表面屈光力近视患者术后角膜生物力学观察

Corneal Biomechanical Changes to Myopia Patients of High Corneal Anterior Surface Refractive Power after LASIK Assisted with Intralase Femtosecond Laser

目的研究飞秒激光辅助LASIK治疗高角膜前表面屈光力近视患者术后角膜生物力学的变化情况。方法高角膜前表面屈光力近视患者64例104只眼,根据ORBSCAN角膜地形图检查角膜前表面屈光力不同,分为实验组和对照组两组。实验组患者32例52只眼,角膜前表面屈光力>47 D;对照组患者32例52只眼,角膜屈光力<47 D。两组患者均采用飞秒激光辅助LASIK手术治疗,观察两组患者术前、术后3和6个月角膜前表面屈光力、眼反应分析仪检测的角膜补偿眼压、Goldmann相关眼压、角膜阻力因子、角膜滞后量以及超声测量中央角膜厚度的变化。结果两组患者角膜厚度、ORA各测量值及角膜前表面屈光力术后3个月的测量值明显低于术前,差异均有显著意义(P<0.05);两组患者术后3个月的测量值与术后6个月比较,差异无显著意义(P>0.05)。结论飞秒激光辅助LASIK手术治疗单纯角膜前表面屈光力>47 D但角膜后表面高度正常、角膜厚度正常的患者,其术后3个月后角膜生物力学各测量值基本稳定,术后6个月角膜生物力学与正常角膜前表面屈光力改变基本一致。

Objective To preliminarily evaluate the safety and stability of intralase femtosecond laser for the LASIK performed on myopia patients with high anterior surface corneal refractive power. Methods Thirty-two patients （52 eyes） of high anterior corneal surface refractive power （ ≥47 D） detected with Obscan-II topography and given LASIK surgery with the assistance of intralase femtosecond laser were selected as the study group （the height of their posterior surface was normal）. Another 32 cases （52 eyes） with a corneal anterior surface refractive power less than 47 D and given intralase femtosecond laser-assisted LASIK formed the control group. The corneal compensated intraocular pressure （ IOPcc）, Goldmann correlated IOP value （IOPg）, corneal resistance factor （CRF） and corneal hysteresis （CH） of both groups were measured with ocular response analyzer （ORA） and the central corneal thickness （CCT） with corneal topography 1,3 and 6 months after the surgery respec- tively. The parameters of the two groups were compared and analyzed statistically. Results For both groups, the CCT, IOPcc, IOPg, CH, CRF and anterior surface corneal refractive power before the surgery were significantly different （P 〈 0. 05） from those 3 months after the surgery. At Month 3 and 6 after the surgery, no obvious difference existed between the study group and control group in CCT, IOPcc, IOPg, CH, CRF and anterior surface corneal refractive power. No apparent change （P〉0.05） occurred to CCT, IOPcc, IOPg, CH and CRF immediately after the operation. Conclusions As to the myopia patients with an anterior surface corneal refractive power over 47D and a normal height of posterior surface, the changes of the corneal biomechanics accorded with those with a normal anterior surface corneal refractive power. The values of the corneal biomechanics were stable 3 months after the surgery.