朝比奈 哲也, 遠藤 信行, 茂木 龍太

Tetsuya ASAHINA, Nobuyuki ENDOH, Ryuta MOGI

神奈川大学　工学部　電気工学科

Department of Electrical Engineering, Faculty of Engineering, Kanagawa University

キーワード : Nonlinearity Parameter, in vitro, Thermodynamic Method

In the last ten years, research on nonlinear acoustics has been widely reported in the medical ultrasonics fields. We will able to diagnose the stage of illnesses qualitatively by measuring B⁄A values in–vivo, because the B⁄A values contain significant physical information about tissue. For the final diagnosis, we need to acquire many kinds of B⁄A values. We measured the B⁄A values of animal tissue in–vitro using the thermodynamic method. We found that the temperature dependences of B⁄A for pork liver, fat and an agar phantom ranged from 20 to 40 degrees. Pork liver and fat have B⁄A values of 7.8 to 9.2 and 10.2 to 11.2, respectively, and the agar phantom was 5.0 to 5.6. These values linearly increased with temperature.