Among many medical imaging modalities including X-ray computed tomography (CT) and magnetic resonance imaging (MRI), medical ultrasound possesses its unique advantage of non-ionizing, real-time, and non-invasive properties. With its safeness, ease of use, and cost-effectiveness, ultrasound imaging has been used in wide variety of diagnostic applications. Further, by the emergence of photoacoustic imaging, ultrasound and photoacoustic imaging can comprehensively depict not only anatomical but also functional information of biological tissue. Photoacoustic imaging is hybrid imaging modality merging light and ultrasound, and reveals the tissue metabolism and molecular distribution with the utilization of endo- and exogenous contrast agents.
To broaden the impact of translational ultrasound and photoacoustic imaging, I have devoted my effort on developing enabling technologies and exploring associated applications. Particularly, this dissertation focuses on; (1) Enabling Technologies for Translational Photoacoustic Imaging We investigated the potential of maximizing the access to translational photoacoustic imaging instead of using widely used customized data acquisition system and expensive high power laser, but by using clinical ultrasound scanner and low-cost light source. (2) Co-robotic Ultrasound and Photoacoustic Imaging We introduced a co-robotic ultrasound paradigm to make ultrasound and photoacoustic imaging more comprehensive and capable of imaging deep tissue in higher resolution and wider field-of-view. (3) Advancements on Translational Photoacoustic Imaging We explored the new use of translational photoacoustic imaging for molecular-based cancer detection and sensing neurotransmitter activity in brain.
Haichong “Kai” Zhang was born in China, and raised in Japan. He received a B.S. and M.S. in Human Health Sciences (Laboratory Science) from Kyoto University, Japan in 2011 and 2013, respectively. After completing his master degree, he joined the Ph.D. program at The Johns Hopkins University, and received M.S. in Computer Science in 2015. His research interests include medical imaging related to medical ultrasound, robotics, photoacoustics. He has authored or presented more than 9 journal articles, 28 conference proceedings, 12 other abstracts, and 4 pending/issued patents.