By Prof. Habib Zaidi, Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, Switzerland
& Department of Nuclear Medicine and Molecular Imaging, University of Groningen, The Netherlands
& Department of Nuclear Medicine, University of Southern Denmark, Odense, Denmark
Early diagnosis and therapy increasingly operate at the cellular, molecular or even at the genetic level. As diagnostic techniques transition from the systems to the molecular level, the role of multimodality molecular imaging becomes increasingly important. Positron emission tomography (PET), x-ray computed tomography (CT) and magnetic resonance imaging (MRI) are powerful techniques for in vivo imaging. The inability of PET to provide anatomical information is a major limitation of standalone PET systems. Combining PET and CT proved to be clinically relevant and successfully reduced this limitation by providing the anatomical information required for localization of metabolic abnormalities. However, this technology still lacks the excellent soft-tissue contrast provided by MRI. Standalone MRI systems reveal structure and function, but cannot provide insight into the physiology and/or the pathology at the molecular level. The combination of PET and MRI, enabling truly simultaneous acquisition, bridges the gap between molecular and systems diagnosis. MRI and PET offer richly complementary functionality and sensitivity; fusion into a combined system offering simultaneous acquisition will capitalize the strengths of each, providing a hybrid technology that is greatly superior to the sum of its parts. However, the technology suffers from a number of drawbacks that will be discussed in this lecture.
This talk reflects also the tremendous increase in interest in quantitative molecular imaging using deep learning techniques in the past decade to improve image quality and to obtain quantitatively accurate data from dedicated combined PET/CT and PET/MR systems including algorithms used to correct for physical degrading factors and to quantify tracer uptake and volume for radiation therapy treatment planning. Future opportunities and the challenges facing the adoption of multimodality imaging technologies and their role in biomedical research will also be addressed.
Professor Habib Zaidi is Chief physicist and head of the PET Instrumentation & Neuroimaging Laboratory at Geneva University Hospital and faculty member at the medical school of Geneva University. He is also a Professor of Medical Physics at the University of Groningen (Netherlands), Adjunct Professor of Medical Physics and Molecular Imaging at the University of Southern Denmark, Adjunct Professor of Medical Physics at Shahid Beheshti University and visiting Professor at Tehran University of Medical Sciences. He is actively involved in developing imaging solutions for cutting-edge interdisciplinary biomedical research and clinical diagnosis in addition to lecturing undergraduate and postgraduate courses on medical physics and medical imaging. His research is supported by the Swiss National Foundation, private foundations and industry (Total 7.1 M US$) and centres on hybrid imaging instrumentation (PET/CT and PET/MRI), deep learning for various imaging applications, modelling medical imaging systems using the Monte Carlo method, development of computational anatomical models and radiation dosimetry, image reconstruction, quantification and kinetic modelling techniques in emission tomography as well as statistical image analysis, and more recently on novel design of dedicated PET and PET/MRI scanners. He was guest editor for 11 special issues of peer-reviewed journals dedicated to Medical Image Segmentation, PET Instrumentation and Novel Quantitative Techniques, Computational Anthropomorphic Anatomical Models, Respiratory and Cardiac Gating in PET Imaging, Evolving medical imaging techniques, Trends in PET quantification (2 parts), PET/MRI Instrumentation and Quantitative Procedures and Clinical Applications, and Nuclear Medicine Physics & Instrumentation and serves as founding Editor-in-Chief (scientific) of the British Journal of Radiology (BJR)|Open, Senior Editor for the British Journal of Radiology and member of the editorial board of Medical Physics, International Journal of Imaging Systems and Technology, International Journal of Biomedical Imaging, Clinical and Translational Imaging, American Journal of Nuclear Medicine and Molecular Imaging, Brain Imaging Methods (Frontiers in Neuroscience & Neurology), Cancer Translational Medicine and the IAEA AMPLE Platform in Medical Physics. He has been elevated to the grade of fellow of the IEEE, AIMBE and the AAPM and was elected liaison representative of the International Organization for Medical Physics (IOMP) to the World Health Organization (WHO) and member of the International Medical Physics Certification Board (IMPCB) and the Imaging Physics Committee of the American Association of Physicists in Medicine (AAPM) in addition to being affiliated to several International medical physics and nuclear medicine organisations. He is developer of physics web-based instructional modules for the RSNA and Editor of IPEM’s Nuclear Medicine web-based instructional modules. He is involved in the evaluation of research proposals for European and International granting organisations and participates in the organisation of International symposia and conferences. His academic accomplishments in the area of quantitative PET imaging have been well recognized by his peers and by the medical imaging community at large since he is a recipient of many awards and distinctions among which the prestigious 2003 Bruce Hasegawa Young Investigator Medical Imaging Science Award given by the Nuclear Medical and Imaging Sciences Technical Committee of the IEEE, the 2004 Mark Tetalman Memorial Award given by the Society of Nuclear Medicine, the 2007 Young Scientist Prize in Biological Physics given by the International Union of Pure and Applied Physics (IUPAP), the prestigious (100’000$) 2010 kuwait Prize of Applied sciences (known as the Middle Eastern Nobel Prize) given by the Kuwait Foundation for the Advancement of Sciences (KFAS) for “outstanding accomplishments in Biomedical technology”, the 2013 John S. Laughlin Young Scientist Award given by the AAPM, the 2013 Vikram Sarabhai Oration Award given by the Society of Nuclear Medicine, India (SNMI), the 2015 Sir Godfrey Hounsfield Award given by the British Institute of Radiology (BIR), the 2017 IBA-Europhysics Prize given by the European Physical Society (EPS) and the 2019 Khwarizmi International Award given by the Iranian Research Organization for Science and Technology (IROST). Prof. Zaidi has been an invited speaker of over 160 keynote lectures and talks at an International level, has authored over 570 publications (he is the senior or first author in a majority of these publications), including 300 peer-reviewed journal articles in prominent journals (ISI-h index=47|61 Web of Science™|Google scholar, >13’330+ citations), 250 conference proceedings and 38 book chapters and is the editor of four textbooks on Therapeutic Applications of Monte Carlo Calculations in Nuclear Medicine, Quantitative Analysis in Nuclear Medicine Imaging, Molecular Imaging of Small Animals and Computational anatomical animal models.