Center for Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506, USA.
J Biomed Opt. 2013 Mar;18(3):037001. doi: 10.1117/1.JBO.18.3.037001.
The dual-wavelength diffuse correlation spectroscopy (DCS) flow-oximeter is an emerging technique enabling simultaneous measurements of blood flow and blood oxygenation changes in deep tissues. High signal-to-noise ratio (SNR) is crucial when applying DCS technologies in the study of human tissues where the detected signals are usually very weak. In this study, single-mode, few-mode, and multimode fibers are compared to explore the possibility of improving the SNR of DCS flow-oximeter measurements. Experiments on liquid phantom solutions and in vivo muscle tissues show only slight improvements in flow measurements when using the few-mode fiber compared with using the single-mode fiber. However, light intensities detected by the few-mode and multimode fibers are increased, leading to significant SNR improvements in detections of phantom optical property and tissue blood oxygenation. The outcomes from this study provide useful guidance for the selection of optical fibers to improve DCS flow-oximeter measurements.
双波长漫射相关光谱（DCS）流量血氧计是一种新兴技术，可实现深层组织中血流和血氧变化的同时测量。在研究人体组织时，应用 DCS 技术时，高信噪比（SNR）至关重要，因为人体组织中的检测信号通常非常微弱。在这项研究中，对单模、少模和多模光纤进行了比较，以探索提高 DCS 流量血氧计测量 SNR 的可能性。在液体体模溶液和体内肌肉组织中的实验表明，与使用单模光纤相比，使用少模光纤仅能略微改善流量测量。然而，少模和多模光纤检测到的光强度增加，导致体模光学特性和组织血氧检测的 SNR 显著提高。这项研究的结果为选择光纤以改善 DCS 流量血氧计测量提供了有用的指导。
