Rochester, Minnesota


ehman.richard@mayo.edu Clinical Profile


Nuclear magnetic resonance phenomena provide the basis for a rich set of methods for assessing anatomy and function in the living organism. The research objective of Richard L. Ehman, M.D., is to expand the range of tissue, organ and system characteristics that can be noninvasively evaluated with MRI techniques.

Dr. Ehman is best known for his groundbreaking work in medical imaging, specifically in nuclear magnetic resonance and its use in diagnosing a variety of conditions. He is also credited with developing magnetic resonance elastography, which allows physicians to determine the stiffness of internal organs without invasive procedures. His research program is focused on developing new imaging technologies.

Dr. Ehman holds more than 40 patents, and many of these inventions are widely used in medical care. His research has been supported by competitive grants from the National Cancer Institute, National Institute of Biomedical Imaging and Bioengineering, and the National Institute of Aging. Dr. Ehman is a prolific author, with over 600 published articles, books, book chapters, abstracts and commentaries.

Focus areas

  • Medical imaging. Dr. Ehman's studies include investigation of new methods for high resolution MRI of moving structures, techniques of ultrafast MRI and methods for noninvasive mapping of the vascular system, especially the coronary arteries. Studies of the basic physics of motion effects in the magnetic resonance data acquisition process have led to the development of "navigator echo" imaging techniques that are highly suited for resolving structures that are in motion.
  • Vascular flow. Other studies employ MRI to quantitatively assess vascular flow characteristics such as velocity, volumetric rates, and disordered flow or turbulence.
  • MRI innovation. Additional research is directed at developing novel MRI techniques to probe bone trabecular morphology, to measure cellular organization in space and to noninvasively delineate the mechanical properties of the tissue. The objective of the latter project is to develop a technique for "palpation by imaging" to detect cancer and other tissue abnormalities at an early stage. Dr. Ehman's research employs MRI to directly image propagating acoustic waves in tissues, allowing images of viscoelastic properties to be generated.

Significance to patient care

The overarching objective of Dr. Ehman's research is to improve patient outcomes by providing tools for earlier and more accurate diagnosis of coronary diseases, cancers and other tissue abnormalities.

Professional highlights

  • President, Radiological Society of North America (RSNA), 2017; Society of Computed Body Tomography and Magnetic Resonance, 2013-2014; Academy of Radiology Research, 2012-2014; International Society for Magnetic Resonance in Medicine, 2002-2003
  • Blanche R. and Richard J. Erlanger Professor of Medical Research, 2015
  • Member (2010-2013) and chair (2014-2015), board of directors, RSNA
  • Distinguished Investigator Award, Mayo Clinic, 2014
  • Inducted into the National Academy of Sciences Institute of Medicine, 2010
  • Outstanding Researcher Award, RSNA, 2006


Primary Appointment

  1. Consultant, Department of Radiology

Joint Appointment

  1. Consultant, Department of Physiology & Biomedical Engineering

Academic Rank

  1. Professor of Radiology


  1. Research Fellowship Mayo Clinic in Rochester
  2. Research Fellowship - Magnetic Resonance Imaging University of California, San Francisco
  3. Resident - Diagnostic Radiology University of Calgary
  4. Internship Foothills Hospital
  5. MD University of Saskatchewan
  6. BSc - Physics University of Saskatchewan

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