Kagemann Larry, Wollstein Gadi, Wojtkowski Maciej, Ishikawa Hiroshi, Townsend Kelly A, Gabriele Michelle L, Srinivasan Vivek J, Fujimoto James G, Schuman Joel S
University of Pittsburgh School of Medicine, Department of Ophthalmology, Ophthalmology and Visual Sciences Research Center, UPMC Eye Center, Eye and Ear Institute, Pittsburgh, Pennsylvania 15213, USA.
J Biomed Opt. 2007 Jul-Aug;12(4):041212. doi: 10.1117/1.2772655.
We use Fourier domain optical coherence tomography (OCT) data to assess retinal blood oxygen saturation. Three-dimensional disk-centered retinal tissue volumes were assessed in 17 normal healthy subjects. After removing DC and low-frequency a-scan components, an OCT fundus image was created by integrating total reflectance into a single reflectance value. Thirty fringe patterns were sampled; 10 each from the edge of an artery, adjacent tissue, and the edge of a vein, respectively. A-scans were recalculated, zeroing the DC term in the power spectrum, and used for analysis. Optical density ratios (ODRs) were calculated as ODR(Art)=ln(Tissue(855)Art(855))ln(Tissue(805)Art(805)) and ODR(Vein)=ln(Tissue(855)Vein(855))ln(Tissue(805)Vein(805)) with Tissue, Art, and Vein representing total a-scan reflectance at the 805- or 855-nm centered bandwidth. Arterial and venous ODRs were compared by the Wilcoxon signed rank test. Arterial ODRs were significantly greater than venous ODRs (1.007+/-2.611 and -1.434+/-4.310, respectively; p=0.0217) (mean+/-standard deviation). A difference between arterial and venous blood saturation was detected. This suggests that retinal oximetry may possibly be added as a metabolic measurement in structural imaging devices.
我们使用傅里叶域光学相干断层扫描（OCT）数据来评估视网膜血氧饱和度。在17名正常健康受试者中评估了以视盘为中心的三维视网膜组织体积。去除直流和低频A扫描分量后，通过将总反射率积分到单个反射率值来创建OCT眼底图像。对30个条纹图案进行采样；分别从动脉边缘、相邻组织和静脉边缘各采样10个。重新计算A扫描，将功率谱中的直流项归零，并用于分析。光密度比（ODR）的计算方式为ODR(Art)=ln(Tissue(855)/Art(855))/ln(Tissue(805)/Art(805))以及ODR(Vein)=ln(Tissue(855)/Vein(855))/ln(Tissue(805)/Vein(805))，其中Tissue、Art和Vein分别代表在以805纳米或855纳米为中心带宽处的总A扫描反射率。通过威尔科克森符号秩检验比较动脉和静脉的ODR。动脉ODR显著大于静脉ODR（分别为1.007±2.611和 -1.434±4.310；p = 0.0217）（均值±标准差）。检测到动脉血和静脉血饱和度之间存在差异。这表明视网膜血氧饱和度测量可能可以作为一种代谢测量方法添加到结构成像设备中。
