发表机构
Pontificia Universidad Católica del Perú; University of Illinois Urbana-Champaign（秘鲁天主教自治大学; 伊利诺伊大学厄巴纳-香槟分校）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出互补孔径脉冲序列（CAPS），通过相干合成恢复低压信号，无需压力缩放因子即可实现B/A成像，仿真显示偏差小于1.3%，优于耗尽法。
AI 中文摘要
耗尽法（DM）利用低、高压采集的基波带信号，在脉冲回波超声中估计声学非线性参数B/A，但需要精确已知声压缩放因子。这一要求限制了其实验转化，因为超声系统上设置的激励电压与探头处压力之间存在轻微非线性缩放。我们提出一种互补孔径脉冲序列（CAPS），通过对交错发射的子孔径的射频采集进行相干求和，恢复线性缩放的低压信号，而全孔径发射则提供高压信号，同时保持超声系统中配置的相同激励电压。对均匀样本和参考体的在体仿真体模评估了CAPS的四种孔径划分，并在相对缩放因子误差为0.01%至10%的情况下与DM进行了比较。使用DM时，0.1%和1%的误差分别导致绝对B/A偏差高达27.3%和58.3%。CAPS在设定值为9时，平均B/A值为8.9，所有划分的偏差小于1.3%，与理想校准的DM相当。这些结果表明，CAPS无需将压力缩放因子作为重建输入即可保持基于耗尽的B/A估计，支持无需压力比校准的实验和体内实施。
英文摘要
The depletion method (DM) enables the estimation of the acoustic nonlinearity parameter, B/A, in pulse-echo ultrasound using fundamental-band signals from low- and high-pressure acquisitions, but requires accurate knowledge of the acoustic-pressure scaling factor. This requirement limits experimental translation because of the slightly nonlinear scaling between excitation voltage set on the ultrasound system and pressure at the probe. We propose a complementary-aperture pulse sequence (CAPS) that recovers the linearly scaled low-pressure signal by coherently summing RF acquisitions from interleaved transmit subapertures whereas a full-aperture transmission provides the high-pressure signal maintaining the same excitation voltage configured in the ultrasound system. In silico phantoms of a homogeneous sample and a reference evaluated four aperture partitions of CAPS and compared them with the DM under relative scaling-factor errors from 0.01% to 10%. Using the DM, errors of 0.1% and 1% produced absolute B/A biases of up to 27.3% and 58.3%, respectively. CAPS yielded mean B/A values of 8.9 for a prescribed value of 9, with biases of less than 1.3% across all partitions, matching an ideally calibrated DM. These results demonstrate that CAPS preserves depletion-based B/A estimation without using the pressure scaling factor as a reconstruction input, supporting experimental and in vivo implementation without pressure-ratio calibration.
Comments4 pages, 3 figures, accepted to 22nd International Symposium on Medical Information Processing and Analysis (SIPAIM)
