题　目：Microbubbles in Diagnostic and Therapeutic Applications in Medical Ultrasound
报告人：Prof. Dr. Brian Fowlkes (Department of Radiology, Department of Biomedical Engineering, University of Michigan)
时　间：6月14日（周五），上午10:00
地　点：物理馆512会议室

Abstract：
An ultrasonic field can interact with small gas bubbles that occur naturally in the body or when these are introduced as contrast agents. Ultrasound contrast agents based on stabilized microbubbles (<10 micron diameter) can also be eliminated from the imaging plane with modest acoustic fields to provide a method for measuring contrast replenishment and thus perfusion. At sufficiently high ultrasound intensity, microbubbles undergo inertial cavitation where the inertia of the fluid is so large that the bubble has difficulty resisting the collapse. These collapses can result in physical effects to tissue surrounding the bubble ranging from very small hemorrhage sites to complete cellular disruption, termed Histotripsy, depending on the pulse parameters used. An additional method for microbubble introduction is to inject superheated perfluorocarbon droplets that when activated by ultrasound, vaporize to form gas bubbles in a process termed acoustic droplet vaporization (ADV). The droplets (<6 micron diameter) produce relatively large bubbles by ADV within tissue for vascular occlusion. We will discuss the many uses of microbubbles in medical ultrasound, how such innovations are advancing both diagnosis and therapy.
Biography：
Jeffery Brian Fowlkes was born in Little Rock, AR in 1960. He received his B. S. degree in physics from the University of Central Arkansas, Conway, AR in 1983, and his M. S. and Ph.D. degrees from the University of Mississippi, Oxford, MS in 1986 and 1988, respectively, both in physics.
He is currently a Professor of Radiology and Professor of Biomedical Engineering at the University of Michigan, Ann Arbor, MI and Associate Vice President for Research for Health Sciences. He is directing and conducting research in medical ultrasound including the use of gas bubbles for diagnostic and therapeutic applications. His work includes studies of ultrasound contrast agents for monitoring tissue perfusion, acoustic droplet vaporization for bubble production in blood flow control, drug delivery and phase aberration correction, effects of gas bubbles in high intensity ultrasound and volume flow estimation using ultrasonic imaging. He has over 150 peer-reviewed scientific publications and over 250 abstract presentations.
Dr. Fowlkes is a fellow of the American Institute of Ultrasound in Medicine and has served as Secretary and as a member of its Board of Governors. He also received the AIUM Presidential Recognition Award and the Joseph H. Holmes Pioneer Award in Basic Science. As a member of the Acoustical Society of America, Dr. Fowlkes has served on the Physical Acoustics Technical Committee and the Medical Acoustics and Bioresponse to Vibration Technical Committee. As a Member of the IEEE, he has worked with the IEEE I&M Society Technical Committee on Imaging Systems. Dr. Fowlkes is a fellow of the American Institute of Medical and Biomedical Engineering and the Acoustical Society of America.