Keynote 9 Measuring Viscoelastic Properties of Soft Tissues
Date/Time Saturday, 4 May 2013 / 10:10 – 10:50
Venue Riverfront Ballroom

Mayo Foundation for Medical Education and Research,

James F. Greenleaf received his Ph.D. degree in Engineering Science from the Mayo Graduate School of Medicine, Rochester, MN, and Purdue University in 1970. He is currently Professor of Biomedical Engineering and Associate Professor of Medicine, Mayo Graduate School, and Consultant, Department of Physiology and Biomedical Engineering, and Internal Medicine, Division of Cardiovascular Diseases, Mayo Clinic Rochester. Doctor Greenleaf has 17 patents and is a Fellow of the IEEE, AIUM, AIMBE, and the ASA. His special field of interest is ultrasonic biomedical science, and he has published more than 450 articles and edited or authored multiple books in the field.

Propagating shear waves in tissue can be measured with high frame rate Doppler or correlation methods, or with regular beam forming methods. The inverse problem for material properties such as complex viscoelastic modulus can be solved using physics models appropriate to the geometry and properties of the tissue, but requires measurement of the propagation characteristics of the shear waves, such as speed versus frequency. This inverse problem includes calculating the storage and loss modulus as a function of frequency and requires appropriate tissue motion, which in turn requires high signal to noise measurements of distributions dynamic radiation force. Iwill discuss novel radiation force distributions that provide enhanced tissuemotion. Ultrasonic measurement of these motions allow the solution of the inverse problem of determining tissue viscoelastic material properties.