Development and validation of a combined photoacoustic micro-ultrasound system for in vivo oxygen saturation estimation

Photoacoustic (PA) Imaging can estimate the spatial distribution of oxygen saturation (sO 2 ) and total hemoglobin concentration (HbT) in blood, and be co-registered with B-Mode ultrasound images of the surrounding anatomy. This study will focus on the development of a PA imaging mode on a commercially available array based micro-ultrasound (μUS) system that is capable of creating such images. The system will then be validated in vivo against a complementary technique for measuring partial pressure of oxygen in blood (pO 2 ). The pO 2 estimates are converted to sO 2 values based on a standard dissociation curve found in the literature. Finally, the system will be used for assessing oxygenation in a murine model of ischemia, both during injury and recovery.