Our Radiologists

Mark H. Awh, M.D.

President

Mark H. Awh, M.D. is a founder of Radsource and a leading authority on Magnetic Resonance Imaging (MR). Dr. Awh is well known for his expertise in musculoskeletal MR and provides numerous lectures on the subject at national radiology meetings. He has co-authored a textbook on magnetic resonance imaging of the spine as well as…

Michael E. Stadnick, M.D.

Medical Director

Michael E. Stadnick, M.D. is a founding member of Radsource. Before joining Radsource, Dr. Stadnick established himself as a successful and respected radiologist specializing in musculoskeletal MR. Dr. Stadnick is a board-certified radiologist who received his residency training at SUNY Health Science Center at Syracuse. Following his residency, Dr. Stadnick was invited to remain as…

Leon R. Toye, M.D.

Medical Director

Leon R. Toye, M.D. has more than 15 years of musculoskeletal MRI experience and serves as a Radsource Medical Director. Prior to joining Radsource, Dr. Toye served as the Director of Musculoskeletal Radiology at Baylor University Medical Center in Dallas, Texas. Dr. Toye was highly esteemed by the radiology residents and fellows for his teaching…

Elizabeth Carpenter, M.D.

Elizabeth L. Carpenter, M.D. is an accomplished musculoskeletal radiologist with a passion for sports medicine imaging. She graduated with high honors from Wake Forest University, and then earned her medical degree at Stony Brook University School of Medicine.  Dr. Carpenter completed residency in diagnostic radiology at NYU Langone Medical Center, where she served as Chief…

Joanna Costello, M.D.

Joanna Costello, M.D., is an accomplished musculoskeletal radiologist who obtained her bachelor’s degree from Lehigh University. She attended medical school at the Medical College of Pennsylvania and completed her radiology residency at Mercy Hospital of Pittsburgh. Dr. Costello then completed a musculoskeletal radiology fellowship at the University of Pittsburgh Medical Center. Prior to joining Radsource,…

Jarrod Dale, M.D.

Jarrod Dale, M.D. is an accomplished diagnostic and interventional musculoskeletal radiologist with extensive experience in both academic medicine and private practice. Dr. Dale graduated summa cum laude from Texas State University with a degree in biochemistry and molecular biology. He earned his medical degree with additional distinction in research at the University of Texas Southwestern…

Benjamin A. Eyer, M.D.

Benjamin A. Eyer, M.D., is a highly skilled radiologist who specializes in musculoskeletal and spine imaging. He graduated Magna Cum Laude from the University of San Diego and went on to earn his medical degree at the Medical College of Wisconsin. Dr. Eyer’s post-graduate training included an internship in preliminary medicine at Weiss Memorial Hospital,…

Travis J. Hillen, M.D.

Travis J. Hillen, M.D., is an accomplished musculoskeletal radiologist and a prolific contributor to academic radiology. Prior to joining Radsource, Dr. Hillen served on the faculty at Washington University School of Medicine as an Associate Professor of Radiology at the Mallinckrodt Institute of Radiology. Dr. Hillen earned his undergraduate degree from Blackburn University in Carlinville,…

Gary A. Howell, M.D.

Gary A. Howell, M.D. is a highly experienced musculoskeletal radiologist and interpreter of MRI. Dr. Howell completed a radiology residency at the University of Cincinnati Medical Center in Cincinnati, Ohio, where he served as Chief Resident. Following residency, Dr. Howell received additional training in musculoskeletal MRI at the San Francisco Magnetic Resonance Imaging Center, under…

Ingrid Kjellin, M.D.

Ingrid Kjellin, M.D. joined Radsource in 2007 after ten years as an attending in Musculoskeletal Radiology at the Loma Linda University Medical Center, where she served as Chief of Musculoskeletal Radiology since 2000. Ingrid Kjellin served as Chief of Musculoskeletal Radiology since 2000. Dr. Kjellin was born in Sweden and attended college and Medical School…

Todd E. Lanier, M.D.

Todd Ellison Lanier, M.D., is a board-certified neuroradiologist who earned his bachelor’s degree at the University of Georgia, graduating Magna Cum Laude. After earning his medical degree at the Medical College of Georgia, Dr. Lanier completed internship and diagnostic radiology residency at Baylor College of Medicine. Following residency, Dr. Lanier completed a two-year fellowship in…

Malisa Lester, M.D.

Malisa S. Lester, M.D. is a highly experienced neuroradiologist well-recognized by her peers for her expertise in neurological MRI. Prior to joining Radsource, Dr. Lester was a partner at Diagnostic Imaging Alliance of Louisville, a busy private radiology practice where she has worked since 2017. She previously served as an Assistant Professor of Radiology in…

Violeta Nikac, M.D.

Violeta Nikac, M.D. joins Radsource after gaining broad experience in both private practice and as an attending radiologist in musculoskeletal imaging at Harvard Medical School, where she instructed residents and fellows at the Brigham and Women’s Hospital for 5 years. Dr. Nikac graduated magna cum laude from Union College and subsequently was granted a Master…

Ashwin Prabhu, M.D.

Ashwin Prabhu, M.D. graduated with high honors from the University of California Davis, and then earned his medical degree at Tufts University School of Medicine. After completing a transitional year internship through Harvard Medical School, Dr. Prabhu completed his residency in Diagnostic Radiology at the University of Southern California (USC). After his residency, he completed…

Stephen F. Quinn, M.D.

Stephen F. Quinn completed both his undergraduate studies and his medical degree at the University of North Carolina, graduating with honors in both cases. His internship and residency were performed at the University of Virginia, under the direction of renowned musculoskeletal radiologist Theodore E. Keats. Dr. Quinn then completed a fellowship in Body Imaging and…

Donald Resnick, M.D.

Dr. Donald Resnick’s illustrious career spans a period of over 38 years spent primarily at UCSD, where he is Chief of Osteoradiology. He has served as a reviewer or on the editorial board of over 30 peer-reviewed journals, a function he is well suited for, as he has published over 850 peer-reviewed articles in orthopaedic…

David A. Rubin, M.D., F.A.C.R.

David A. Rubin, M.D. is a highly accomplished musculoskeletal radiologist who obtained his bachelor’s degree from Brown University. He is an Alpha Omega Alpha graduate of the University of Pennsylvania School of Medicine. He completed his radiology residency and musculoskeletal radiology fellowship at the Hospital of the University of Pennsylvania in Philadelphia, where he also…

Jeffrey A. Simon, M.D.

Dr. Jeffrey A. Simon performed his undergraduate studies at the University of Rochester, where he graduated cum laude with a B.S. major in neurosciences and a minor in economic theory. During his college tenure, Dr. Simon was selected to attend the undergraduate honor school in biochemistry and neurosciences at Oxford University, England. Dr. Simon attended…

Christopher R. Smith, M.D.

Christopher R. Smith, M.D. is a highly regarded musculoskeletal radiologist who joins Radsource after serving as Director of Musculoskeletal Imaging at Baylor University Medical Center in Dallas, Texas and as an affiliate instructor at Texas A&M College of Medicine.  Armed with a Columbia University biomechanical engineering degree, Dr. Smith graduated #1 in his medical school…

James Derek Stensby, M.D.

J. Derek Stensby, M.D. is a highly skilled musculoskeletal radiologist with extensive clinical experience. Dr. Stensby most recently has served as an Associate Professor of Musculoskeletal Radiology at the University of Missouri, where he was the Residency Program Director and Musculoskeletal Imaging Fellowship Director. Prior to his time in Missouri, he was an Assistant Professor…

Katharine Tansavatdi, M.D.

Katharine Tansavatdi, M.D., is a highly experienced neuroradiologist who obtained her bachelor’s degree in Integrative Biology from the University of California, Berkeley, where she was inducted into Phi Beta Kappa. She attended medical school at Wake Forest University, where she received an NIH Medical Student Research Fellowship. Following an internship at Sacred Heart Medical Center…

Phillip F. J. Tirman, M.D.

Phillip F. J. Tirman, M.D. is a highly accomplished musculoskeletal radiologist who is well-recognized by his peers as an expert in the use of MRI for evaluating orthopaedic, sports medicine and spine disorders. Prior to joining Radsource, Dr. Tirman served as Medical Director at Renaissance Medical Imaging Associates, a leading provider of diagnostic imaging services…

Alice B. Viroslav M.D.

Alice B. Viroslav, M.D. received dual BAs in biology and psychology from Southern Methodist University, where she graduated Cum Laude. After graduating from the University of Texas Southwestern Medical School in Dallas, Dr. Viroslav completed her Diagnostic Radiology residency and Neuroradiology fellowship at Emory University, serving as Chief Resident in her fourth year of residency.…

James Y. Wu, M.D.

James Y. Wu, M.D. is an accomplished musculoskeletal radiologist with a passion for sports medicine imaging. He graduated from Duke University, where he was a Howard Hughes research scholar and recognized on the Dean’s List, then went on to earn his medical degree at New York Medical College. Dr. Wu completed an internship at North…