Project Summary / Abstract for the Center for Molecular Imaging Technology and Translation The Center for Molecular Imaging Technology and Translation (CMITT) is a National Center for Biomedical Imaging and Bioengineering located within the Gordon Center for Medical Imaging (GCMI) at the Massachusetts General Hospital. Working within the interdisciplinary environment (e.g., imaging and data sciences; image reconstruction, processing and AI; pharmacokinetics; radiochemistry) of the Gordon Center, the aim of the CMITT is to develop, validate and disseminate cutting-edge imaging technologies that take advantage of the game-changing capabilities afforded by simultaneous acquisition of PET and MR. CMITT approaches PET/MR as a truly synergistic modality, with novel radiochemistry, kinetic modeling, quantitative methods, image reconstruction and AI that exploit properties of PET and MR signals. Thus CMITT advances the methodology of PET/MR and covers the entire range of radiochemistry/radiopharmacy to image formation and processing including tomographic reconstruction and estimation/quantitation, paving the way for research applications and clinical translation. Our pioneering work during the initial funding cycle, Y1-4, of our P41 in quantitative PET/MR, has provided solutions to some of the most vexing problems affecting PET/MR, including reliable and accurate corrections for attenuation and involuntary subject motion (TR&D 1 in Y1-4). We have provided unique contributions to PET quantitation and image reconstruction by using deep learning (TR&D 2 in Y1-4). We have also advanced novel radioligands and new molecular measurements, starting from first concept to actual application (TR&D 3 in Y1-4). Accordingly, in this renewal application, we are in a strong position to propose and develop new field-leading technologies pertaining to Molecular Imaging using PET and MR. The TR&D1 of the renewal develops and delivers multi-parametric quantitative PET/MR imaging technologies that not only enable physiological high-impact novel PET/MR but will also benefit standalone MR research. The TR&D2 of the renewal develops an innovative artificial intelligence-based pipeline of data processing in PET/MR, including image reconstruction, transfer learning, and uncertainty estimation. The TR&D3 of the renewal uses the developments achieved in TR&Ds 1&2 to translate applications of PET/MR from physiological concept to measurements in animal models and then on to first-in-human studies. The National Resource provides a unique environment with an interdisciplinary team of highly accomplished scientists, engineers, and clinicians with diverse expertise in multiple modalities and disciplines that supports service use of the Center's facilities by imaging scientists throughout the country as well as Canada and Australia. CMITT will provide extensive training opportunities for students, post-doctoral fellows, and faculty, and seeks to advance the field of molecular imaging of n...