角膜屈光手术后人工晶状体屈光度计算方法的选择

Clinical selection of IOL refractive corneal refractive surgery calculation method

目的:探讨角膜屈光手术后白内障患者进行超声乳化联合人工晶状体(intraocular lens,IOL)植入手术的临床效果,对不同IOL屈光度准确性进行比较。方法:对我院收治的120例160眼接受白内障手术并曾行角膜屈光手术的治疗近视患者相关资料进行分析,采用病史法对可获得角膜屈光手术前的角膜曲率数据K值进行计算,采用矫正角膜曲率数值法以及角膜地形图法对患者治疗前后资料记录不完整者K值,将K值代入公式,通过比较白内障术后实际屈光状态和预期屈光状态(-0.50D),比较三种计算方法IOL屈光度准确性。结果:白内障患者手术前平均最佳矫正视力为0.25±0.05,术后最佳矫正视力提高0.80±0.05;白内障患者手术前平均等效球镜值(spherical equivalent,SE)为-1.98±1.75,患者手术后SE为+0.85±3.38(P<0.05);48眼临床病史调查法(CHM)计算K值;73例采用校正角膜曲率数值法(AKM)计算K值;39例采用角膜地形图法(CTM)计算K值。结论:对具有角膜屈光手术史患者根据患者临床症状、病史等选择合适的方法,能够准确地计算患者IOL,对于资料完整者采用CHM提供角膜K值;对于资料不完整者采用AKM和CHM计算K值。

AIM： To investigate the clinical effect of phacoemulsification and intraocular lens（ IOL）implantation for cataract patients after corneal refractive surgery,and to compare the accuracy of the different refractive IOL.METHODS： The data of 120 myopia cases（ 160 eyes） in our hospital,who underwent cataract surgery and corneal refractive surgery were analyzed. Corneal curvature K value before corneal refractive surgery were obtained and calculated by using history method. Corneal curvature correction numerical method and corneal topography were used to record K value of patients with incomplete data before and after treatment. The K value was substituted into the formula. By comparing the actual cataract surgery and refractive state expected refractive status（-0. 50D）,the accuracy of IOL refractive obtained from three methods was compared.RESULTS： The average best corrected visual acuity before cataract surgery was 0. 25 ± 0. 05, and it was improved（ 0. 80 ± 0. 05） after surgery. The average spherical equivalent（ SE） was- 1. 98 ± 1. 75 before surgery and ＋0. 85 ± 3. 38 after surgery（ P 〈 0. 05）. The K values of 48 cases were calculated by clinical history method（ CHM） and that of 73 cases was calculated with the adjusted keratometry method（ AKM）. The K values of39 cases were calculated using the corneal topography method（ CTM）.CONCLUSION： For patients with corneal refractive surgery, the appropriate method can be selected according to clinical symptoms,history,etc. and this may help to accurately calculate IOL. For patients with complete data,CHM can be used to provide corneal K values,while for those with incomplete data,AKM and CHM can be used.