水浴法B超在高度近视眼白内障患者生物测量中的准确性研究

摘要

目的 比较水浴法B超、A超、IOLMaster 3种方法测量高度轴性近视眼白内障患者眼轴的准确性.方法 前瞻性研究.对2012年1至5月在解放军总医院眼科行超声乳化白内障摘除及人工晶状体植入术的高度轴性近视眼白内障患者40例(66只眼),分别用水浴法B超、接触式A超和IOLMaster 3种方法测量眼轴长度,IOLMaster测量角膜曲率,SRK/T公式计算IOL度数,术后3个月检查患者屈光状态.结果 水浴法B超测得的眼轴均值为(27.91±1.96) mm,接触式A超为(27.71 ±2.15)mm,IOLMaster为(27.88±2.04) mm;水浴法B超与IOLMaster法比较差异无统计学意义(=0.726,P=0.473),而接触式A超测得的眼轴短于水浴法B超(t=2.223,P=0.003)和IOLMaster法(t=2.614,P=0.014),差异均有统计学意义.术后3个月绝对屈光度数误差≤±0.50 D者水浴B超多于接触式A超,差异有统计学意义(x2=5.67,P＜0.05),与IOLMaster 间差异无统计学意义(x2=0.06,P＞0.05);绝对屈光度数误差≤±1.00D者,水浴法B超多于接触式A超,差异有统计学意义(x2 =4.19,P＜0.05),与IOLMaster比较差异无统计学意义(x2=0.36,P＞0.05).结论 水浴法B超在轴性高度近视眼生物测量中具有和IOLMaster法一致的准确性,优于A超.%Objective To compare the accuracy of axial length measurement with three methods,that is,immersion B-scan,contact A-scan,and IOLMaster in high myopia with cataract.Methods To analyze the data of the 40 patients (66 eyes),who were all high myopia with cataract and accepted the phacoemulsification and fold-able lens implantation surgery in our hospital from Jan 2012 to May 2012.The measurement of axial length was performed respectively in 66 eyes by immersion B-scan,contact A-scan and IOLMaster.Keratometric power was measured preoperatively by IOLMaster.The IOL power calculation was carried out according to SRK/T formula in the basis of IOLMaster.Their refraction outcome was follow-up three months after operation.Results The axial length was (27.91 ± 1.96) mm,(27.71 ±2.15)mm,(27.88 ± 2.04) mm respectively by immersion B-scan,A-scan and IOLMaster.There was no significant difference between immersion B-scan and IOLMaster method (t =0.726,P =0.473).But the axial length measured by contact A-scan was shorter than that tested by immersion B-scan(t =2.223,P =0.003) and IOL Master(t =2.614,P =0.014)significantly.There was significant difference between immersion B-scan and contact A-Scan method in those patients whose mean absolute refractive error (MARE) was within ± 0.50 Diopter three months after operation(x2 =5.67,P ＜ 0.05),while there was no significant difference between immersion B-scan and IOLMaster measurement (x2 =0.06,P ＞ 0.05).The same situation happened in those patients whose MARE was within ± 1.00 Diopter.That means,there was significant difference between immersion B-scan measurement and contact A-scan measurement (x2 =4.19,P ＜0.05),while there was no significant difference between immersion B-scan and IOLMaster measurement (x2 =0.36,P ＞ 0.05).Conclusions The immersion B-Scan measurement is better than A-scan,and it is as accurate as the IOL Master measurement,which is another good choice for the axial length measuring in high myopia with cataract cases.