血管壁高频超声弹性显示微成像研究

The elasticity of arterial wall tissues has very close relationship with physiological status and pathological changes of cardiovascular system. Strain estimation and elasticity imaging has drawn much attention for its low cost and risk and it is very valuable for diagnosis and therapy of cardiovascular diseases to apply this modality. During the last three years, we make much effort to research the biomechanical properties and microscopic elasticity imaging of artery wall mainly using the Intravascular Ultrasound (IVUS) technique. Our studies include displacement and strain estimation of artery wall, elasticity reconstruction of artery wall, experiments of mimicking phantom and in vitro and in vivo porcine artery. Furthermore we extend our research to strain estimation of soft tissue and shell of microbubble and quantitative evaluation of soft tissue contusion. Achievements acquired in our research are ①Displacement and strain estimation of artery wall and soft tissue utilizing ultrasound rf signal, including a method based on Principle Component Analysis (PCA) neural network and a method using the matched filter in time-scale domain based on wavelet transform to position the regular scatterer and calculate the local scatterer spacing and its change. ②Displacement and strain estimation of artery wall and soft tissue utilizing ultrasound images, including a Genetic Algorithm Based Optical Flow Method (GAOF) and a Genetic Algorithm Based Correlation Feedback Technique (GACF). ③Applying elasticity reconstruction method to artery wall and soft tissue, acquiring the 'real'elasticity distribution images. ④Having made a lot of experiments of mimicking phantom，in vitro and in vivo artery and soft tissue and improved strain estimation method and the strategy of the experiments. These studies may have potentials to provide new technological means for monitoring and evaluating Percutaneous Transluminal Coronary Angioplasty (PACT) procedure and elasticity characterization of soft tissue.

提出将血管壁高频超声弹性显微成像的新方法，将血管力学在体研究推进到亚同毫米微结构层次主要研究（1）血管内高频超声传播特性和图像预处理；（2）非刚性血管组织线性与非线性应变小误差位移与应变声估计方法；（3）线性与非线性应变血管弹性重构理论与方法停?）对PTCA过程临控与疗效评价的关键技术。对血管力学、心血管系统生理与心血管评价等具有重要价值。