Rubinoff Ian, Kuranov Roman V, Zhang Hao F
Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.
Opticent Health, Evanston, IL 60201, USA.
Biomed Opt Express. 2020 Dec 8;12(1):110-124. doi: 10.1364/BOE.410011. eCollection 2021 Jan 1.
Visible-light optical coherence tomography (vis-OCT) has enabled new spectroscopic applications, such as retinal oximetry, as a result of increased optical absorption and scattering contacts in biological tissue and improved axial resolution. Besides extracting tissue properties from back-scattered light, spectroscopic analyses must consider spectral alterations induced by image reconstruction itself. We investigated an intrinsic spectral bias in the background noise floor, which is hereby referred to as the spectrally-dependent background (SDBG). We developed an analytical model to predict the SDBG-induced bias and validated this model using numerically simulated and experimentally acquired data. We found that SDBG systemically altered the measured spectra of blood in human retinal vessels in vis-OCT, as compared to literature data. We provided solutions to quantify and compensate for SDBG in retinal oximetry. This work is particularly significant for clinical applications of vis-OCT.
可见光光学相干断层扫描（vis-OCT）由于生物组织中光吸收和散射接触增加以及轴向分辨率提高，实现了新的光谱应用，如视网膜血氧测定。除了从背向散射光中提取组织特性外，光谱分析还必须考虑图像重建本身引起的光谱变化。我们研究了背景噪声本底中的固有光谱偏差，在此将其称为光谱依赖性背景（SDBG）。我们开发了一个分析模型来预测SDBG引起的偏差，并使用数值模拟和实验获取的数据对该模型进行了验证。我们发现，与文献数据相比，SDBG系统性地改变了vis-OCT中人体视网膜血管内血液的测量光谱。我们提供了在视网膜血氧测定中量化和补偿SDBG的解决方案。这项工作对vis-OCT的临床应用尤为重要。
