Photoacoustic elastography based on laser-excited shear wave  

作　　者：Yang Liu Ruoyi Shi Gang Li Mingjian Sun 

机构地区：[1]School of Astronautics,Harbin Institute of Technology,Harbin 150000,P.R.China [2]School of Information Science and Engineering,Harbin Institute of Technology,Weihai 264200,P.R.China

出　　处：《Journal of Innovative Optical Health Sciences》2024年第3期56-72,共17页创新光学健康科学杂志（英文）

基　　金：supported by the National Key R&D Program of China(Grant No.2022YFC2402400);the National Natural Science Foundation of China(Grant No.62275062);and Guangdong Provincial Key Laboratory of Biomedical Optical Imaging Technology(Grant No.2020B121201010-4).

摘　　要：Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of tissues.In this study,we propose a new method for shear wave elastography(SWE)based on laser-excited shear wave,called photoacoustic shear wave elastography(PASWE),which combines photoacoustic(PA)technology with ultrafast ultrasound imaging.By using a focused laser to excite shear waves and ultrafast ultrasonic imaging for detection,high-frequency excitation of shear waves and noncontact elastic imaging can be realized.The laser can stimulate the tissue with the light absorption characteristic to produce the thermal expansion,thus producing the shear wave.The frequency of shear wave induced by laser is higher and the frequency band is wider.By tracking the propagation of shear wave,Young’s modulus of tissue is reconstructed in the whole shear wave propagation region to further evaluate the elastic information of tissue.The feasibility of the method is verified by experiments.Compared with the experimental results of supersonic shear imaging(SSI),it is proved that the method can be used for quantitative elastic imaging of the phantoms.In addition,compared with the SSI method,this method can realize the noncontact excitation of the shear wave,and the frequency of the shear wave excited by the laser is higher than that of the acoustic radiation force(ARF),so the spatial resolution is higher.Compared to the traditional PA elastic imaging method,this method can obtain a larger imaging depth under the premise of ensuring the imaging resolution,and it has potential application value in the clinical diagnosis of diseases requiring noncontact quantitative elasticity.

关 键 词：ELASTOGRAPHY shear wave PHOTOACOUSTIC Young's modulus 

分 类 号：TN24[电子电信—物理电子学]