Sumi Chikayoshi
Department of Electrical and Electronics Engineering, Faculty of Science and Technology, Sophia University, Tokyo, Japan.
IEEE Trans Ultrason Ferroelectr Freq Control. 2008 Feb;55(2):297-307. doi: 10.1109/TUFFC.2008.649.
An effective setting method (that is, a method using the variances of strain tensor component measurements) is described for the properly spatially varied regularization parameters for our shear modulus reconstruction. At each position, the respective strain variances can be experimentally evaluated using plural field measurements or single field measurement, for example, when using all crosscorrelation- based methods, by using the Ziv-Zakai Lower Bound (ZZLB). The demonstrated regularization by the single field measurement using the cross-spectrum phase gradient method (MCSPGM) in experiments confirms that the use of the axial strain variance estimated by the echo signal-to-noise ratio and correlations (the combined SNRc) effectively stabilizes the 1-D reconstruction on an agar phantom and a human in vivo liver carcinoma during interstitial microwave thermal treatment. The regularization yields a spatially uniform stability in reconstruction.
本文描述了一种有效的设置方法（即一种利用应变张量分量测量方差的方法），用于为我们的剪切模量重建确定适当的空间变化正则化参数。在每个位置，可以通过多个场测量或单场测量来实验评估各自的应变方差，例如，当使用所有基于互相关的方法时，可通过使用齐夫-扎凯下界（ZZLB）来评估。实验中使用互谱相位梯度法（MCSPGM）进行单场测量所展示的正则化证实，利用回波信噪比和相关性估计的轴向应变方差（组合信噪比c）能有效地稳定在琼脂模型和人体体内肝癌的间质微波热疗过程中的一维重建。这种正则化在重建中产生空间均匀的稳定性。
