双通道双焦点光学相干断层扫描仪的研制及其准确性和重复性检测

目的运用自主研发的一套双通道双焦点频域光学相干断层扫描仪（OCT）对人全眼成像．并检验该仪器的准确性和重复性。方法横断面自身对照研究。随机抽样选取21例（39眼）健康志愿者．第1天依次运用双通道双焦点OCT和IOLMaster测量前房深度及眼轴长度，第2天运用双通道双焦点OCT再次测量。比较2种仪器的测量值及第1天和第2天OCT的测量值。数据分析采用配对t检验、Pearson相关分析及Bland—Altman分析。结果运用双通道双焦点OCT可实时获得全眼图像，测得实际前房深度为（3．09±0．20）mm，眼轴长度为（25．34±0．64）mm。第l天和第2天OCT实际前房深度和眼轴长度测量值差异均无统计学意义（t=-1．648、1．129，P〉0．05）。IOLMaster测得前房深度为（3．58±0．21）mm，眼轴长度为（25．24±0．65）mm。OCT测得前房深度为（3．64±0．20）mm。2种仪器在测量前房深度及眼轴长度时差异均有统计学意义（t=12．942、8．984，P〈0．05）。两者测量前房深度和眼轴长度的相关系数分别为0．990和0．997。前房深度及眼轴长度测量的95％LoA分别为（0．001，0．119）mm及（-0．018，0．178）mm。结论自主研制的双通道双焦点OCT可实时获得全眼图像，是一种重复性较好的全眼参数的测量仪器，它具有操作方便、非接触性及实时获得高分辨率眼前节图像的优点。

Evaluation of the accuracy and repeatability of the dual channel dual focus optical coherence tomography for the whole eye

Objective To evaluate a custom-buih dual channel dual focus spectral domain optical coherence tomography （OCT） instrument for imaging the whole eye in vivo, to demonstrate the feasibility and repeatability of this OCT instrument to measure anterior chamber depth and axial length compared to the IOLMaster. Methods In a cross-sectional self-control study, 21 volunteers （39 eyes） without a history of ocular disease were enrolled. The anterior chamber depth （ACD） and total axial length （AL） were measured by the custom-buih dual channel dual focus OCT and IOLMaster on the first day, and then by the OCT on the second day. The measurements of the two instruments were compared and the measurements with the OCT were compared for the 2 days. A paired t test, Pearson correlation analysis and Bland-Ahman analysis were used for data analysis. Results The ocular surfaces from the cornea to the retina could be assessed with this newly built dual channel dual focus spectral domain OCT in real time. The mean and standard deviation of the real anterior chamber depth and total axial length measured by the OCT system were 3.09±0.20 mm and 25.34±0.64 mm, respectively. No significant differences were found in the measurements with OCT taken on different days （t=-1.648, 1.129; P〉0.05）. The mean and standard deviation of the anterior chamber depth and total axial length measured by IOLMaster were 3.58±0.21 mm and 25.24±0.65 mm, respectively. The mean and Standard deviation of the anterior chamber depth by OCT was 3.64±0.20 mm. There was a significant difference in measuring the anterior chamber depth and total axial length with the OCT and IOLMaster （t=12.942, 8.984, P〈0.05）. There was a high correlation in anterior chamber depth （r=0.990, P〈0.01 ） and total axial length （r=0.997, P〈0.01 ） measurements by the 2 devices. The 95% LoA （limits of agreement） were ＋0.001 mm to ＋0.119 mm and -0.018 mm to ＋0.178 mm for measurements of ACD and AL by the OCT and IOLMaster. Conclusion Real-time whole eye images were successfully assessed by the custom-made dual channel dual focus OCT. There is good feasibility and repeatability with this newly built system.