Abstract

On Nonlinear Acoustics Methods in Medical Diagnostics

A.M.Sutin (Stevens Institute of Technology, Hoboken, and Institute of Applied Physics RAN, Nizhny Novgorod, Russia); S.Y.Emelianov (Biomedical Engineering Department, University of Michigan, Ann Arbor, MI, USA); A.M.Tatarinov, A.P.Sarvazyan (Artann Laboratories, North Brunswick, NJ, USA)

e-mail: asutin@stevens-tech.edu

In the last decade, nonlinear acoustics expanded into many area of medical diagnostics, therapy and surgery. This presentation is aiming at exploring new medical applications of nonlinear acoustics based approaches. 1. Nonlinear Wave Modulation Spectroscopy (NWMS): a vibration induced ultrasound modulation technique is proposed for detection of bone abnormalities and assessment of bone aging-related changes in bone quality and fracture risk. NWMS sensitivity to the presence of bone microdamages could be much higher than that of conventional methods of bone diagnostics. NWMS can reveal subtle changes in bone microarchitecture. Preliminary in-vitro studies performed on excised bone samples confirming the feasibility of the proposed approach are presented. 2. A technique based on interaction of high-frequency focused ultrasound beams with different frequencies is suggested for remote evaluation of bone mechanical properties closely related to bone health and quality . 3. A method for remote non-invasive assessment of the blood pressure was investigated. This method is based on nonlinear acoustic measurements of resonance frequency of a homogeneous population of microbubbles. The resonance frequency depends on the ambient pressure and microbubbles travelling in the blood steam may act as "microgages" remotely reporting on the variations of local blood pressure. The nonlinear scattering of ultrasound on microbubbles may serve as an noninvasive tool for assessing t of vascular system functionality.

Section : 5