A multi-channel diffuse correlation spectroscopy system for dynamic topography of blood flow index in deep tissues

Abstract

Near-infrared (NIR) diffuse correlation spectroscopy (DCS) provides a novel tool for clinical blood flow monitoring. Although DCS has the advantages of non-invasiveness, high sensitivity and large penetration depth, increasing its acquisition speed to achieve real-time imaging is still an on-going task. In this work, we propose a multi-channel DCS system for dynamic topography of blood flow index in deep tissues, where a dynamic nature up to one frame per second is implemented by combining the concurrency of FPGA-based 10 channel hardware correlators of multi-τ -design and NIR-sensitive avalanche photodiode detectors. The flow-velocity resolution, measurement fidelity and imaging depth of the system were evaluated by phantom experiments. In vivo experiments on human arm were then performed that accurately imaged the shape and position of the blood vessels and demonstrated the ability of the proposed methodology to capture blood flow changes.