基于相移的实时超声弹性成像方法  

Real Time Ultrasound Elastography Based on Phase Shift

作　　者：孙瑞超[1] 唐亚男[1] 谢林培[1] 何丹妮[1] 陆敏华[1,2,3] 汪天富[1,2,3] 陈思平[1,2,3] 

机构地区：[1]深圳大学生物医学工程系,深圳518060 [2]医学超声关键技术国家地方联合工程实验室,深圳518060 [3]广东省生物医学信息检测与超声成像重点实验室,深圳518060

出　　处：《中国生物医学工程学报》2013年第3期339-347,共9页Chinese Journal of Biomedical Engineering

基　　金：国家自然科学基金(60901015;61031003);深圳市科技计划(JC201005280385A)

摘　　要：准静态超声弹性成像是分别采集组织压缩前和压缩后的超声回波信号,从信号变化提取组织运动并对组织弹性成像的一种超声成像技术。本研究提出一种基于块匹配和相移的混合算法,首先根据块匹配对复杂的位移场进行预估,然后根据预估值采用相移算法进行精细估计。为了验证该方法的有效性,用仿真的射频信号定量比较了新提出算法和之前发表的基于先验估计的算法,结果表明本研究中的方法无论是信噪比还是对比度噪声比都高于之前算法。以仿真的应变2%,泊松比0.49为例,基于先验估计的算法信噪比是3.82,而新算法的信噪比为10.85。同时弹性体模和病人数据实验表明,该算法对于复杂的人体组织仍然具有较好的鲁棒性。结果证明提出的新算法是一种精度高,鲁棒性好的实时弹性成像算法。Quasi-static ultrasound elastography is an imaging modality to track tissue motion from ultrasonic signals before and after compression to image tissue elasticity. In this study, we presented a framework combined with block matching algorithm （BMA） and phase shift method （PS） for displacement estimation. BMA was first applied to the radio frequency （RF） signals, the displacements obtained were then used as a prior estimates of the PS method to calculate a more precision axial displacements. The performance of the algorithm was evaluated with synthesis data, and the result showed that both SNRe and CNRe of our method were significantly higher than those of PSPE method. In the case of strain value at 2% and Poisson＇s ratio 0.49, the SNRe of PSPE and new algorithm were 3.82 and 10.85, respectively. The proposed algorithm was further validated using both elasticity phantom data and clinical data. Results showed that our method was robust to relatively complex tissue motions. The proposed algorithm was also fast, which provides real time strain images.

关 键 词：实时 超声弹性成像 二维位移估计 相移 

分 类 号：R318[医药卫生—生物医学工程]