Validation of SMURF Estimation of Shear Modulus in Hydrogels
Validation of SMURF Estimation of Shear Modulus in Hydrogels
复制标题
DOI：
10.1177/016173460903100204
复制
发表时间：
2009-04-01
影响因子：
2.3
通讯作者：
Menon, Manoj
中科院分区：
文献类型：
--
作者：
McAleavey, Stephen;Collins, Erin;Menon, Manoj
对空间调制超声辐射力（SMURF）方法进行了剪切模量估计的验证研究。SMURF估计均匀明胶和Zerdine（TM）幻影覆盖的模量范围为2至18千帕的无侧限机械压缩和声弹性成像获得的结果进行了比较。结果表明，在所有三种方法所示的范围内的测量不确定度的协议。对于在体模内单个点进行的观察，发现体模模量的重复性和变化约为5%。对来自若干相邻扫描线的模量估计求平均进一步减小了变化。通过使用多个辐射力峰值来诱导已知波长的剪切波并测量波的频率，SMURF从沿沿着单个A线采集的跟踪数据获得模量估计。这是重要的，因为散斑可以使剪切波的测量相位偏置。SMURF被证明是不敏感的剪切波测量中的恒定相位误差。与在多个位置处跟踪并且不消除相位误差的方法相比，这导致模量估计中的相关噪声大大减少。
A validation study of the Spatially Modulated Ultrasound Radiation Force (SMURF) method for shear modulus estimation is presented. SMURF estimates of uniform gelatin and Zerdine (TM) phantoms covering a modulus range of 2 to 18 kPa are compared with results obtained by unconfined mechanical compression and sonoelastography. The results show agreement within the measurement uncertainties over the range indicated for all three methods. Repeatability and variation on the order of 5% of the phantom modulus are found for observations made at a single point within the phantom. Averaging of modulus estimates from several adjacent scan lines further decreases the variation. By using multiple radiation force peaks to induce a shear wave of known wavelength and measure the frequency of the wave, SMURF obtains modulus estimates from tracking data acquired along a single A-line. This is significant, as speckle can bias the measured phase of the shear wave. SMURF is shown to be insensitive to a constant phase error in the shear wave measurement. This results in greatly reduced correlated noise in the modulus estimates, in contrast with methods which track at multiple locations and do not cancel phase errors.