Faculty & Staff

Mark Bohlman, M.D., FACR, Chair
Chairman, Department of Imaging at Johns Hopkins Bayview
Associate Professor of Radiology

Mark Bohlman, M.D., FACR, a lifelong local (Baltimore) resident, was born in Bon Secours Hospital and grew up in Baltimore County. As a teenager, he attained the rank of Eagle Scout in the Boy Scouts. Dr. Bohlman has practiced radiology at Johns Hopkins Bayview since 1980. Throughout his time at the Medical Center, he has seen many changes.

Dr. Bohlman graduated from the University of Maryland Baltimore County in 1972 with a degree in biology. He earned a medical degree at the University of Maryland Medical School in 1976. He also completed a residency in radiology at the University of Maryland Medical Center. Dr. Bohlman is a fellow of the American College of Radiology.

A past president of the Maryland Radiologic Society, Dr. Bohlman currently is a counselor from Maryland to the College of Radiology. He specializes in cross-sectional radiology and image-guided interventional radiology.
Residing in the Baltimore area with his wife, MaryEllen, and their four children, Dr. Bohlman is an avid salt-water sports fisherman. On most days off, you may find him in the Chesapeake Bay or on one of the Bay’s tributaries fishing or cruising by boat with his wife.

Dr. Bohlman thoroughly enjoys working with and joining in the education of medical residents. He especially enjoys overseeing medical student education and spending time with numerous students rotating through the imaging department at Johns Hopkins Bayview.

Martin Auster, M.D., MBA
Director, Interventional Radiology
Assistant Professor of Radiology

Martin Auster, M.D., MBA, assistant professor of radiology at The Johns Hopkins University School of Medicine and director of interventional radiology at Johns Hopkins Bayview, earned a medical degree at Hahnemann Medical College in Philadelphia. He completed a residency in radiology at Montefiore Hospital, followed by fellowships in neuroradiology and cardiovascular interventional radiology.

In 2005, Dr. Auster earned an MBA from The Johns Hopkins University Carey School of Business. Before coming to Johns Hopkins Bayview, he maintained a private radiology practice.

Dr. Auster has been married for 28 years to Adrian Dobs, M.D., also a Johns Hopkins physician. Together, they have four children and one grandchild. In his free time, Dr. Auster enjoys skiing, tennis and traveling.

Maha Barazanji, M.D.
Medical Director, Imaging - Johns Hopkins at White Marsh
Clinical Associate of Radiology

Maha Baranzanji, M.D., is committed to her philosophy that every patient deserves high-quality imaging and comprehensive, thorough reporting, as well as providing excellent imaging consultation to referring physicians.

Dr. Barazanji earned a medical degree at the University of Baghdad Medical School and completed a residency in diagnostic radiology at Stony Brook University Medical Center. She also completed a fellowship in body imaging at The Johns Hopkins University School of Medicine.

Board-certified by the American Board of Radiology, Dr. Barazanji holds a special interest in body imaging CT, US and MRI, female pelvic ultrasound and MRI, breast MRI and acute abdomen imaging.

John Cavaluzzi, M.D.
Director, Neuroradiology
Assistant Professor of Radiology

John Cavaluzzi, M.D., earned a medical degree at Manhattan College (Downstate Medical Center) in New York and completed a residency in radiology at Kings County Hospital. After serving two years in the U.S. Navy and one year in private practice, Dr. Cavaluzzi completed a fellowship in cardiovascular radiology. He has served director of neuroradiology at Johns Hopkins Bayview since 1980.

A senior member of the American Society of Neuro-radiology, Dr. Cavaluzzi has published research articles on several topics, including hepatic venography, pulmonary embolism and applications of HASTE MRI techniques in neuroradiology. He has reviewed research articles submitted for publication in the American Journal of Neuroradiology.

Dr. Cavaluzzi holds research interests in applications of the high field (3 Tesla) MRI to the evaluation of patients with stroke and cerebrovascular disease.

I. Semra Engin, M.D.
Clinical Associate of Radiology

I. Semra Engin, M.D., clinical associate in radiology at The Johns Hopkins University School of Medicine, holds over 20 years experience in diagnostic radiology practice. She earned a medical degree at the University of Ankara in Turkey and completed a fellowship in nuclear medicine at The Johns Hopkins University School of Medicine.

Board-certified in diagnostic radiology, Dr. Engin oversees mammography services at both Johns Hopkins Bayview and Johns Hopkins at White Marsh.

Joel Fradin, M.D.
Director, Ultrasound
Instructor of Radiology

Joel Fradin, M.D., earned an undergraduate degree in biology at City College of New York and a medical degree at State University of New York at Downstate. He completed a residency in diagnostic radiology at Winthrop-University Hospital and a fellowship in body imaging at State University of New York at Stony Brook.

Joining Johns Hopkins Bayview in 1993, Dr. Fradin maintains a strong interest in resident teaching and hands-on diagnostic ultrasound.

In his free time, Dr. Fradin enjoys gardening, cooking and baseball.

Gary X. Gong, M.D., Ph.D.
Assistant Professor of Radiology

Gary Gong, M.D., Ph.D., assistant professor of radiology at The Johns Hopkins University School of Medicine, has multidisciplinary training in diagnostic and interventional radiology, neuroradiology, and thoracic surgery and research. After practicing interventional and general diagnostic radiology for several years in China, he earned a medical degree at Temple University School of Medicine and completed a residency in diagnostic radiology at Yale-Norwalk Hospital. Dr. Gong also completed a fellowship in neuroradiology at The Johns Hopkins Hospital.

Primarily, Dr. Gong practices diagnostic neuroradiology, but also offers other radiological services with the exception of mammography and nuclear medicine. He has expertise in neurological CTA, spine facet joint block, nerve root block, epidural steroid injection and pain management. His strong interventional skills include tumor RF and cryo-ablations.

Dr. Gong’s research interests focus 3D applications, high field MRI stroke imaging and interventional techniques.

Young Choo Kim, M.D.
Assistant Professor of Radiology

Young Choo Kim, M.D., earned an undergraduate pre-med degree, as well as a medical degree, at Yon-Sei University in Seoul, Korea. He completed a residency in radiology at University of Missouri Medical Center in Columbia, Missouri and training in pediatric radiology at Mercy Children’s Hospital in Kansas City, Missouri.

Dr. Kim now is an assistant professor of radiology at The Johns Hopkins University School of Medicine and practices mammography and general radiology at Johns Hopkins Bayview Medical Center.

Erich K. Lang, M.D.
Professor of Radiology

Erich K. Lang, M.D., professor of radiology at The Johns Hopkins University School of Medicine, earned a medical degree at the University of Vienna in Austria. He holds clinical interests in interventional, urogynecologic and oncologic radiology.

An author of numerous medical publications, abstracts, books and chapters, Dr. Lang also is active in academic research in radiology. His research focuses largely in the fields of interventional radiology and uroradiology, as well as urology, gynecology and the oncologic aspects of each.

Jonathan Marx, M.D.
Instructor of Radiology

Jonathan Marx, M.D., born and raised in Morristown, New Jersey, earned an undergraduate degree in biological psychology at the University of Michigan and a medical degree at the University of Medicine and Dentistry of New Jersey—Robert Wood Johnson Medical School.

After completing two-year residency in general surgery following medical school, he became interested in interventional radiology and completed a residency in radiology at Morristown (NJ) Memorial Hospital. He then pursued a fellowship in interventional radiology at The Johns Hopkins Hospital.

Dr. Marx joined Johns Hopkins Bayview in 2007. A member of the Society of Interventional Radiologists, he especially enjoys the diversity of procedures involved in interventional radiology.

In his free time, Dr. Marx enjoys spending time with his family. He often can be found boating on the Chesapeake Bay during the summer or skiing during the winter.

John Petronis, M.D.
Director, Nuclear Radiology
Associate Professor of Radiology

John Petronis, M.D., holds over 25 years of experience in nuclear medicine. He earned degrees in electrical engineering and biomedical engineering at Rutgers University and a medical degree at the University of Medicine and Dentristry of New Jersey - Robert Wood Johnson Medical School. He completed a residency in radiology at Hershey Medical Center and a fellowship in nuclear medicine at The Johns Hopkins Hospital.

A member of the Society of Nuclear Medicine, SNM Cardiovascular Council and Editorial Board of Clinical Nuclear Medicine, Dr. Petronis holds a special interest in nuclear cardiology, cardiac MRI and clinical applications of PET-CT technology.

Nathan R. Sklar, M.D.
Assistant Professor of Radiology

Nathan R. Sklar, M.D., earned a medical degree at Temple University School of Medicine. He completed an internship in medicine and a residency in radiology at the U.S. Public Health Service Hospital in Baltimore, as well as a second residency in radiology at Thomas Jefferson University Hospital.

Board-certified in diagnostic radiology, Dr. Sklar holds special interests in mammography as well as gastrointestinal radiology.

Jessie D. Stahl, M.D.
Clinical Associate of Radiology

Jessie D. Stahl, M.D., earned a medical degree at the University of Maryland School of Medicine, where she also completed a residency in radiology.

A board-certified radiologist, Dr. Stahl holds over 30 years experience and specializes in mammography. She maintained a private practice in radiology for over 25 years before joining Johns Hopkins Bayview in 2006.

Dr. Stahl is a member of the American College of Radiology and Society of Breast Imaging.