Photoacoustic imaging of the spatial distribution of oxygen saturation in an ischemia-reperfusion model in humans
Aboma Merdasa, Josefine Bunke, Magdalena Naumovska, John Albinsson, Tobias Erlöv, Magnus Cinthio, Nina Reistad, Rafi Sheikh, Malin Malmsjö
Abstract
Photoacoustic imaging (PAI) is a novel hybrid imaging technique that combines the advantages of optical and ultrasound imaging to produce hyperspectral images of the tissue. The feasibility of measuring oxygen saturation (sO 2 ) with PAI has been demonstrated pre-clinically, but has limited use in humans under conditions of ischemia and reperfusion. As an important step towards making PAI clinically available, we present a study in which PAI was used to estimate the spatial distribution of sO 2 in vivo during and after occlusion of the finger of eight healthy volunteers. The results were compared with a commercial oxygen saturation monitor based on diffuse reflectance spectroscopy. We here describe the capability of PAI to provide spatially resolved picture of the evolution of sO 2 during ischemia following vascular occlusion of a finger, demonstrating the clinical viability of PAI as a non-invasive diagnostic tool for diseases indicated by impaired microvascularization.