Ultrasound imaging to monitor photothermal therapy - Feasibility study

This study investigates the feasibility of ultrasound imaging to monitor temperature changes during photothermal treatment. Experiments were performed on tissue-mimicking phantoms and ex-vivo animal tissue samples. Gold nanoparticles were utilized as photoabsorbers. Prior to laser irradiation, structural features of the phantoms and tissue were visualized by ultrasound imaging. Ultrasound thermal imaging, performed during laser heating, showed that the temperature elevation was localized to the region of embedded or injected nanoparticles. The results of our study suggest that ultrasound imaging is a candidate approach to remotely guide photothermal therapy. (C) 2008 Optical Society of America.