A超和IOL Master测量不同眼轴长度区间的眼轴长度和前房深度的比较

目的:评估A超测量不同眼轴长度区间的眼轴长度(AL)和中央前房深度(ACD)的可重复性,并与IOL Master检查结果比较,为临床实践提供依据.方法:选取白内障患者170例257眼,术前分别行IOL Master和A超检查,其中每只受试眼IOL Master自动测量5次,A超测量3次,分别取平均值.按A超测得的AL分为5组:A组:2129mm(21眼).Cronbach's Alpha系数及组内相关系数(ICC)评估A超测量AL和ACD的可重复性.配对样本t检验和Pearson相关系数分析各组中A超和IOL Master测量的AL和ACD的差异性和相关性.Bland-Altman分析A超和IOL Master测量的AL和ACD的一致性.结果:A超测量的AL和ACD的Cronbach's Alpha系数和ICC均大于0.98.A、B、C、D、E组中, A超测量的AL与IOL Master测量的AL差值分别为-0.11±0.08、-0.15±0.10、-0.19±0.15、-0.29±0.16、-0.45±0.29mm,差异均有统计学意义(均P<0.01);ACD差值分别为-0.10±0.16、-0.06±0.13、-0.06±0.13、-0.19±0.10、-0.18±0.21mm,差异均有统计学意义(均P<0.01).A、B、C、D、E组中,A超和IOL Master测量的AL和ACD均具有很好的相关性(均r >0.89,P<0.01).结论:A超测量白内障患者的AL和ACD具有很好的可重复性,且数值均比IOL Master小;其中不同眼轴长度的差异,随着眼轴的增长而增大.

Comparison of axial length and anterior chamber depth obtained by A scan ultrasonography and IOL Master in different axial length groups

AIM:To evaluate the repeatability of axial length (AL) and anterior chamber depth (ACD) obtained by A scan ultrasonography, and to compare AL and ACD obtained by A scan with those obtained by IOL Master.METHODS:Two hundred and fifty-seven cataract eyes of 170 patients were included.IOL Master and A scan were performed for each eye.Five measurements of IOL Master and 3 measurements of A scan were obtained.All the tested eyes were divided into 5 groups according to AL obtained by A scan:Group A (2129mm, 21 eyes).Cronbach's Alpha coefficient and intraclass correlation coefficient (ICC) were applied to evaluate the repeatability of AL and ACD obtained by A scan.Paired t test and Pearson correlation coefficient were used to analyze the differences and correlations of AL and ACD obtained by the 2 devices, respectively.Bland-Altman plots were presented to analyze the agreements of AL and ACD obtained by the 2 devices.RESULTS:All the Cronbach's Alpha and ICCs of AL and ACD values were more than 0.98.The differences of AL values between A scan and IOL Master were-0.11±0.08mm in Group A,-0.15±0.10mm in Group B,-0.19±0.15 mm in Group C,-0.29±0.16mm in Group D and-0.45±0.29mm in Group E, respectively (all P<0.01).The differences of ACD values between A scan and IOL Master were-0.10±0.16mm in Group A,-0.06±0.13mm in Group B,-0.06±0.13mm in Group C,-0.19±0.10mm in Group D,-0.18±0.21mm in Group E, respectively (all P<0.01).In all groups, the AL and ACD values obtained by A scan and IOL Master presented good correlations (all r>0.89, all P<0.01).CONCLUSION:The AL and ACD values in cataract eyes obtained by A scan were repeatable.The AL and ACD values obtained by A scan were smaller than those obtained by IOL Master.With the increase of AL values, the differences of AL values between A scan and IOL Master increased.