James F. Greenleaf, Ph.D.

In the ultrasound research laboratory we investigate a wide range of ultrasound related fields including, imaging, therapy, theory and practice.

We have recently invented a new imaging method termed Vibro-acoustography (Science 280:82-85,1998). The method produces speckle free images of tissues and objects, and can be used to obtain spectroscopic analyses of tissue or object motion. We are building a breast scanner using this technology and with Dr Dana Whaley we will test it on patients. With GE we are building a vibroacoustic scanner for use in radiology. We also investigate, with Dr. Mark Bolander's laboratory, the mechanisms responsible for ultrasound accelerated fracture healing. We are developing methods of measuring myocardial and vascular mechanical properties with ultrasound. We have recently developed methods of measuring tissue material properties using displacements measured from vibrated tissues with ultrasound. We have also used basic scattering theory to develop new methods of characterizing tissue from ultrasound signals. We are measuring fundamental material properties of arteries by exciting modes of vibration using radiation force of ultrasound.