光线追踪法用于角膜屈光术后人工晶状体度数计算准确性分析  

Ray tracing software for intraocular lens power calculation after corneal excimer laser surgery

作　　者：刘盛涛[1] 邹晶[1] 张小雪 古学军[1] LIU Shengtao;ZOU Jing;ZHANG Xiaoxue;GU Xuejun(Department of Cataract,Affiliated Eye Hospital of Nanchang University,Nanchang 330006,China;The Second Affiliated Hospital of Nanchang University,Nanchang 330006,China)

机构地区：[1]南昌大学附属眼科医院白内障科,江西南昌330006 [2]南昌大学第二附属医院眼科

出　　处：《中国实用眼科杂志》2018年第4期315-318,共4页Chinese Journal of Practical Ophthalmology

基　　金：江西省科技计划项目(20151BBG70245)。

摘　　要：目的探讨光路追踪法对角膜屈光手术后人工晶状体(IOL)度数计算的准确性。方法回顾性病例研究。对20例(31只眼)角膜屈光手术后行白内障超声乳化吸除+人工晶状体植入术的患者进行回顾性研究,使用Scheimpfug相机,采用Placido角膜地形图仪(Sirius,天狼星;CSO)内部软件进行I0L度数计算,以I0L Master测量眼轴长度,并与Haigis-L公式计算结果相比较。以术后1个月实际屈光状态与预测屈光状态的误差得出预测误差,并分析其预测误差与绝对预测误差的平均值、标准差及分布。结果Haigis-L公式和光路追踪法的平均预测误差分别为(-0.65+0.46)D和(+0.19+0.34)D,平均绝对预测误差分别为(0.69+0.39)D和(0.30+0.25)D。绝对预测误差值+0.50D范围内分别为35.5%和83.9%,+1.00D范围内分别为83.9%和96.8%,两者比较差异有统计学意义(t=10.38,P<0.05)。结论光路追踪法可对角膜屈光手术后白内障患者进行较为准确的人工晶状体度数计算。与Haigis-L公式相比,光线追踪法计算结果术后屈光状态有偏正趋势。Objective To investigate the accuracy of intraocular lens(IOL)power calculation by raytracing after myopic excimer laser surgery.Methods Retrospective case series of 20 patients(31 eyes)underwent phacoemulsfication and I0L implantation after myopic laser in situ keratectomy was enrolled.IOL power calculation was performed using internal sofware of a Scheimpflug camera combined with a Placido disc cormeal topographer corneal radius(Sirius;CSO).Exact results were carried out after the axial length measured by IOL--Master and compared with those calculated by Haigis-L formula.The predictive error was calculated by the difference between the expected refraction(as calculated by the software)and the actual refraction 1 month after surgery.Median absolute error,mean absolute error,and mean arithmetic error in refraction prediction were analyzed by SPSS17.0 software.Results The mean arithmetic error calculated by Haigis-L and ray tracing were-0.65+0.46D and+0.19+0.34D,respectively.The mean absolute errors were 0.69+0.39D and 0.30+0.25D,respectively.Also,35.5%and 83.9%of the eyes were within土0.50 D of the predicted refraction,83.9%and 96.8%were within土1.00 D in the Haigis-L and ray tracing group,respectively.The difference was statistically significant(t=10.38,P<0.05).Conclusions Ray-tracing can calculate IOL power accurately in eyes with prior myopic laser in situ keratectomy,and showed a positive trend compared with the Haigis-L formula.

关 键 词：光路追踪 人工晶状体 屈光力计算 角膜屈光手术 

分 类 号：R77[医药卫生—眼科]