Lenstar与A超及IOL—Master进行眼部生物测量比较研究

Comparison and evaluation of ocular biometry using the noncontact Lenstar, IOL-Master and contact ultrasound A-scan

目的比较Lenstar与IOL—Master及A超在测量眼轴长度（axial length，AL）、前房深度（anterior chamber depth，ACD）时的差异，分析三种测量方法的一致性，为Lenstar的临床应用提供依据。方法前瞻性临床研究。对2011年12月至2012年3月在北医三院眼科的白内障术前患者及志愿者计78例123只眼，分别应用Lenstar与IOL—Master及A超进行AL、ACD测量，Lenstar与IOL—Master及A超测量值间的差异采用配对t检验，相关性采用Pearson相关分析，一致性采用Bland—Ahman统计分析。结果Lenstar与IOL—Master测量AL及ACD的平均值差值分别为（-0．003±0．048）mm及（-0．044±0．091）mm，其差异均无统计学意义（P=0．517；P=0．573，P〉0．05）。Lentar与A超测量AL及ACD的平均值差值分别为（0．117±0．195）（0．080±0．253）mm，其差异均有统计学意义（P〈0．01）。三种测量方法所获得的AL及ACD均具有密切的线性相关差异有统计学意义（r≥0．916，P〈O．01）。Bland—Altman分析显示，在测量AL及ACD时，Lenstar与IOL—Master的一致性较好，与传统A超测量值的一致性较差。结论在测量眼轴长度及前房深度时，Lenstar与IOL—Master的一致性较好，与传统A超测量值的一致性较差，由于Lenstar具有一次测量可获得多项数据、简单快捷、非接触等优点，是一种在临床中可选择的准确性较高地生物学测量仪器。

Objective To evaluate a new noncomact optical biometer （Lenstar） using optical low-coherence reflectometry and to compare the biometric measurements （axial length, AL and anteri- or chamber depth, ACD） with those obtained from current clinical instrumentation （IOL-Master and ultrasound A-scan）. Methods In this prospective clinical study, measurements of AL and ACD ob- tained from 123 eyes of 78 subjects with the Lenstar were compared with those obtained with the IOL-Master or ultrasound A-scan. The results were evaluated using Bland-Altman analyses. The differ- ences between both methods were assessed using the paired t test, and its correlation was evaluated by Pearson coefficient. Results Lenstar measurements of AL and ACD were similar to the IOL-Mas- ter （average difference=-0.003±0.048mm, P =0.517; average difference=-0.044±0.091mm, P =0.573）, re- spectively. Lenstar measurements of AL and ACD were significantly longer than those of A-scan （av- erage difference=0.117±0.195mm, P 〈0.001; average difference=0.080±0.253mm, P 〈0.001）, respective- ly. A Pearson correlation revealed a high correlation for AL and ACD （r ≥0.916 for all, P 〈0.001 for all）. Bland-Altman plots showed good agreements for AL measurements and ACD between Len- star and IOL-Master and the level of agreement was not acceptable between Lenstar and A-scan. Conclusions For the measurement of AL and ACD, there is good agreement between Lenstar and IOL-Master. Nevertheless, Lenstar and A-scan cannot be used interchangeably. The results, coupled with a unique ability to analyze the ocular structures non-contactly make the Lenstar a promising new instrument for ocular evaluation in research and clinical practice,