In vivo demonstration of real-time oxygen saturation imaging using a portable and affordable LED-based multispectral photoacoustic and ultrasound imaging system

摘要

Photoacoustic imaging is a hybrid medical imaging technique that combines the contrast and spectral sensitivity ofoptical imaging with resolution and tissue penetration of ultrasound. Due to the difference between the optical absorptionspectra of deoxygenated and oxygenated hemoglobin, multispectral photoacoustic imaging holds strong potential in noninvasivelocal blood oxygen saturation imaging. Oxygen saturation imaging is one of the most promising applications ofphotoacoustic imaging and has been widely explored in studies related to tumor hypoxia, cancer therapy etc. However,clinical translation of this technology has often been limited by bulky and expensive excitation sources. Recently, weintroduced a multi-wavelength real-time LED-based photoacoustic/ultrasound imaging system. In this work, potential ofthis LED-based system in real-time oxygen saturation imaging is demonstrated using an in vivo measurement on ahuman volunteer. We used ultra-fast switching two-wavelength LED arrays (750nm/850nm) along with a linear-array 7MHz US probe for the experiments. 2D PA, US, and oxygen saturation imaging were performed on the index finger of ahuman volunteer. Results demonstrate that LED-based PA imaging system used in this study is promising for generating2D/3D oxygen saturation maps along with PA and US images in real-time. We believe that these results will haveprofound impact in non-invasive blood oxygen saturation imaging and subsequent clinical translation of PA-basedoximetry.