Professor of Radiology, Biomedical Engineering, Biochemistry, and Molecular Biophysics. He is director of Washington University Molecular Imaging Center and Director of Optical Radiology Lab. He is Co-Leader, Oncologic Imaging of Siteman Cancer Center - NCI designated Cancer Center of excellence. In 2019 he was recipient of SPIE Britton Chance Award in Biomedical Optics. He achieved lifetime Fellow of American Association for Advancement of Science.