Medical Physicists

js     Jeffrey V. Siebers, Ph.D.

Director of Radiological Physics and Professor of Radiation Oncology and Biomedical Engineering

Dr. Siebers joined the Department of Radiation Oncology, Medical Physics, in 2013.  He received his Ph.D. in Medical Physics from the University of Wisconsin in 1990.  Prior to joining UVA, he was a tenured Professor in the Department of Radiation Oncology at VCU where he was the founding director of the Medical Physics graduate program. Dr. Siebers’ clinical and research interests include treatment optimization, robustness analysis dose assessment accuracy, during treatment delivery quality assurance, radiation dosimetry, quality assurance methods and metrics, clinical safety and efficiency.

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LibbyB     Bruce Libby, Ph.D.

Associate Professor of Radiological Physics and Director of Clinical Physics Residency

Dr. Libby joined the Department of Radiation Oncology as a member of the Clinical Physics faculty in 2008. He received his PhD in Nuclear Chemistry at the University of Maryland. Prior to joining UVA, he was an Assistant Professor of Radiation Oncology Physics at the University of Pittsburgh Medical Center. He is board certified by both the ABMP and the ABR, and was elected as a Fellow of the AAPM in 2016. In his role as the chief of clinical brachytherapy physics, he is working on the development of new brachytherapy applicators and improved methods of patient treatment, including the development of a state of the art Image Guided Brachytherapy (IGBT) Suite and Intra Operative Brachytherapy (IOBT). He also serves as the Director of the Medical Physics residency program where he is actively involved in resident teaching and course organization.

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Krishni Wijesooriya    Krishni Wijesooriya, Ph.D.

Associate Professor of Radiation Oncology and Research Associate Professor of Physics

Dr. Wijesooriya joined UVA faculty in 2008. She received her PhD in Nuclear Physics from William & Mary in 1999.  She initiated many clinical programs at UVA: Total Body Irradiation, Motion Management, deep inspiratory breath hold program for left sided breast treatments.  She has extensive LINAC commissioning experience (TrueBeam, and Trilogy).  She is also the primary physicist involved in national clinical trial protocols at UVA. Her research interested include motion management, DIBH for left breast, log file based QA to improve patient safety, out-of-field d ose measurements and simulations, new imaging modalities, and novel treatment delivery devices.  She has research experience in GEANT4 simulations, and Varian Amazon cloud based Virtual linac simulations. She has 34 publications in peer reviewed journals and 3 book chapters.

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David Schlesinger    David Schlesinger, Ph.D.

Associate Professor of Radiation Oncology

Dr. Schlesinger has worked as an Assistant Professor in the Department of Neurological Surgery since 2004, and formally joined the Clinical Physics Faculty in the Department of Radiation Oncology in 2009. Dr. Schlesinger’s clinical expertise is in stereotactic radiosurgey at the University of Virginia Gamma Knife center, where he assists the radiation oncologist and neurosurgeon to develop minimally invasive treatments for brain tumors and other neurologic conditions. Dr. Schlesinger also works in support of clinical trials at the university’s MR-Guided Focused Ultrasound Surgery Center.  Dr. Schlesinger earned his Ph.D. in Biomedical Engineering from the University of Virginia in 1998. His research interests include image processing, pattern recognition, multi-objective optimization, and systems engineering tools as applied to procedural quality assurance.

Tyler Watkins     William Tyler Watkins, Ph.D.

Assistant Professor of Radiation Oncology

Dr. Watkins joined the Department of Radiation Oncology as a member of the Clinical Physics faculty in 2013. He earned his B.Sc. and M.S. degrees from San Diego State University, in Physics, with an emphasis on computational and medical physics. He went on to work as a research associate at the University of California San Diego before joining the CAMPEP accredited medical physics education program at Virginia Commonwealth University, receiving his Ph.D. in 2013. He supports the University of Virginia Health System, Department of Radiation Oncology, in all aspects of external beam and brachytherapy medical physics. His clinical expertise includes treatment plan optimization, deformable image registration, adaptive radiation therapy, scientific programming, and data systems management. His research is focused on the future of radiation therapy from the perspective of decision analysis, where automated treatment plan optimization and expected utility analysis will transform current, population-derived strategies into personalized radiation treatment.

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