Biomed. Eng. Dept., Duke Univ., Durham, NC, USA.
IEEE Trans Ultrason Ferroelectr Freq Control. 2009 Oct;56(10):2157-66. doi: 10.1109/TUFFC.2009.1298.
Phase correction has the potential to increase the image quality of 3-D ultrasound, especially transcranial ultrasound. We implemented and compared 2 algorithms for aberration correction, multi-lag cross-correlation and speckle brightness, using static and moving targets. We corrected three 75-ns rms electronic aberrators with full-width at half-maximum (FWHM) auto-correlation lengths of 1.35, 2.7, and 5.4 mm. Cross-correlation proved the better algorithm at 2.7 and 5.4 mm correlation lengths (P < 0.05). Static cross-correlation performed better than moving-target cross-correlation at the 2.7 mm correlation length (P < 0.05). Finally, we compared the static and moving-target cross-correlation on a flow phantom with a skull casting aberrator. Using signal from static targets, the correction resulted in an average contrast increase of 22.2%, compared with 13.2% using signal from moving targets. The contrast-to-noise ratio (CNR) increased by 20.5% and 12.8% using static and moving targets, respectively. Doppler signal strength increased by 5.6% and 4.9% for the static and moving-targets methods, respectively.
相位校正有可能提高 3-D 超声（尤其是经颅超声）的图像质量。我们使用静态和动态目标实现并比较了两种像差校正算法，即多步延迟互相关和散斑亮度。我们校正了三个 rms 电子像差，其半最大值全宽（FWHM）自相关长度分别为 1.35、2.7 和 5.4mm。在 2.7 和 5.4mm 的相关长度下，互相关被证明是更好的算法（P<0.05）。在 2.7mm 的相关长度下，静态互相关的性能优于动态目标互相关（P<0.05）。最后，我们在带有颅骨铸造像差的流动体模上比较了静态和动态目标互相关。使用静态目标的信号进行校正，与使用动态目标的信号相比，平均对比度增加了 22.2%。使用静态和动态目标时，对比度噪声比（CNR）分别增加了 20.5%和 12.8%。多普勒信号强度分别增加了 5.6%和 4.9%。
