IOL Master与接触性A超测量人工晶状体度数的对比性观察

A comparative observation on the accuracy of intraocular lens measured with IOL Master and A-scan

目的比较IOL Master与传统接触性A超测量人工晶状体度数的差异性及准确性,评价IOL Master在白内障术前检查中的应用价值。方法对155例(205眼)白内障患者术前分别采用IOL Master、接触性A超联合自动验光仪测量眼轴长度及角膜曲率,随机分为两组后,应用Hoffer-Q/SRK-T公式进行人工晶状体度数测算,所有患者均进行白内障超声乳化联合人工晶状体植入术,应用自动验光仪联合插片验光对两组患者术后3个月屈光状态进行对比性分析。结果应用IOL Master测量的眼轴长度为(24.14±0.34)mm,其中L<23 mm(43眼)眼轴长度(21.54±0.21)mm,23 mm≤L≤26 mm(128眼)眼轴长度为(24.86±0.56)mm、L>26 mm(34眼)眼轴长度为(25.34±0.78)mm;应用接触性A超测量的眼轴长度为(23.94±0.54)mm,其中L<23 mm(48眼)眼轴长度(21.14±0.01)mm,23 mm≤L≤26 mm(127眼)眼轴长度为(24.86±0.56)mm、L>26 mm(30眼)眼轴长度为(25.04±0.28)mm。L<23 mm及23 mm≤L≤26 mm组两者比较无统计学差异(P>0.05),L>26 mm组两者比较有统计学差异(P<0.05)。应用IOL Master测量的角膜曲率为(44.24±0.45)D,应用自动验光仪测量角膜曲率为(43.93±0.25)D;两者对比无统计学差异(P>0.05)。术后3个月L<23 mm组,平均绝对屈光误差分别为(0.35±0.27)D,(0.54±0.25)D,两者对比无统计学差异(P>0.05);23 mm≤L≤26 mm组平均绝对屈光误差分别为(0.25±0.21)D,(0.44±0.24)D两者对比无统计学差异(P>0.05);L大于26 mm组,测量平均绝对屈光误差分别为(0.85±0.31)D,(1.02±0.52)D,两者比较有统计学差异(P<0.05)。结论IOL Master测量人工晶状体度数准确性可靠,尤其在高度近视患者中,准确性较接触性A超更为明显,但仍存在一定的局限性。

Objective To compare the difference and accuracy of IOL Master and traditional contact A-scan for measuring intraocular lens power,and evaluate the application value of IOL Master in preoperative inspection of cataract.Methods The 155 patients(205 eyes)with age-related cataract were included in the study.The patients used the IOL Master,A-scan-automatic refractometer to measure the axial length and corneal curvature before surgery.After divided into two groups randomly,lntraocular lens power was calculated according to the Hoffer-Q/SRK-T/Holladay formula.Cataract phacoemulsification combined with intraocular lens implantation was performed on all patients.Refractive status of patients in the two groups were analysed by automatic refractometer combined with optometry after operation of 3 months.Results The mean axial length was(24.14±0.34)mm measured by IOL Master,of which L<23mm(43 eyes)was(21.54±0.21)mm,23mm≤L≤26mm(128 eyes)was(24.86±0.56)mm,L>26mm(34 eyes)was(25.34±0.78)mm.The mean axial length was(23.94±0.54)mm measured by A-scan,of which L<23mm(48 eyes)was(21.14±0.01)mm,23mm≤L≤26mm(127 eyes)was(24.86±0.56)mm,L>26mm(30 eyes)was(25.04±0.28)mm.There was no significant difference between the two groups in which L<23mm and 23mm≤L≤26mm(P>0.05),and there was significant difference between the two groups in which L L>26mm.The keratometric powers measured by IOL-Master and automatic refractometer were(44.24±0.45)D and(43.93±0.25)D,showing no significant difference(P>0.05).The mean absolute refractive error(MAE)in A-scan group was(0.35±0.27)D and in IOL Master group was(0.54±0.25)D of which L<23mm,and the MAE in A-scan group was(0.25±0.21)D and in IOL Master group was(0.44±0.24)D of which 23mm≤L≤26mm,there was no significant difference between the two groups(P>0.05).For the group of L>26mm,the MAE was(0.85±0.31)D and(1.02±0.52)D,and the difference was statistically significant(P<0.05).Conclusion IOL Master is proved to be slightly more accurate than A-scan for IOL power calculation,especially for high myopia,but there are still some limitations.