Devices and Radiological Health, Food & Drug Admin. Center, Rockville, MD.
IEEE Trans Med Imaging. 1994;13(3):500-7. doi: 10.1109/42.310881.
An autoregressive (AR) method for spectral estimation was applied toward the task of estimating ultrasonic backscatter coefficients from small volumes of tissue. High spatial resolution is desirable for generating images of backscatter coefficient. Data was acquired from a homogeneous tissue-mimicking phantom and from a normal human liver in vivo. The AR method was much more resistant to gating artifacts than the traditional DFT (discrete Fourier transform) approach. The DFT method consistently underestimated backscatter coefficients at small gate lengths. Therefore backscatter coefficient image formation will be quantitatively more meaningful if based on AR spectral estimation rather than the DFT. The autoregressive method offers promise for enhanced spatial resolution and accuracy in ultrasonic tissue characterization and nondestructive evaluation of materials.
一种自回归（AR）谱估计方法被应用于从小体积组织中估计超声背散射系数的任务。高空间分辨率是生成背散射系数图像的理想选择。数据是从均匀组织模拟体模和正常人体肝脏中获取的。与传统的离散傅里叶变换（DFT）方法相比，AR 方法对门控伪影的抵抗能力更强。DFT 方法在小门长下始终低估背散射系数。因此，如果基于 AR 谱估计而不是 DFT 来形成背散射系数图像，那么将更有意义。自回归方法有望提高超声组织特征化和材料无损评估的空间分辨率和准确性。
