摘要
Sub-harmonic contrast imaging promises to improve ultrasound imaging quality by taking advantage of increased contrast to tissue signal.The aim of this study is to examine the hysteretic nonlinearity of sub-harmonic component emitted from microbubbles.Two kinds of microbubble solutions,i.e.Sonovue■and a self-developed contrast agent,are utilized in the study.The hysteretic curves for increasing and decreasing acoustic pressure are theoretically predicted by the Marmottant model and confirmed by measurements.The results reveal that for both microbubble solutions,the development of the rising ramp undergoes three stages,i.e.occurrence,growth and saturation;while hysteresis effect appears in the descending ramp.Sono Vue■microbubbles exhibit better sub-harmonic performance over the self-developed UCAs microbubbles due to the difference of elastic properties of the shell.
作者
QIU Yuan-Yuan
ZHENG Hai-Rong
ZHANG Dong
邱媛媛;郑海荣;章东(Institute of Acoustics,Key Lab of Modern Acoustics,Nanjing University,Nanjing 210093;Institute of Biomedical and Health Engineering,Shenzhen Institutes of Advanced Technology,Chinese Academy of Sciences,Shenzhen 518067)
基金
Supported by the National Basic Research Program of China under Grant No 2010CB732600 and
National Natural Science Foundation of China under Grant Nos 10974093,11011130201 and 10904094 and Key Lab of Acoustics。
