IEEE Trans Ultrason Ferroelectr Freq Control. 2019 Nov;66(11):1731-1748. doi: 10.1109/TUFFC.2019.2931495. Epub 2019 Jul 31.
Three-dimensional plane wave imaging (PWI) with a 2-D array has been studied for ultrafast volumetric imaging in medical ultrasound. Compared to 2-D PWI, 3-D PWI requires the transmission of an increased number of plane waves (PWs) to scan a volume of interest and achieve transmit dynamic focusing in both the lateral and elevational directions. To reduce the number of PW angles for a given 2-D angular range by mitigating the grating lobe level, we propose two aperiodic patterns of PW angles: concentric rings with a uniform radial interval and the well-known sunflower pattern. Both patterns are validated to provide uniform angle distributions without regular periodicity, and thereby reduce the grating lobe level compared to a periodic angle distribution with the same number of PW angles. Simulation studies show that the aperiodic patterns enhance the contrast of B-mode images by approximately 3-6 dB over all depths. This enhancement implies that the aperiodic angle sets can increase the volume rate by approximately 2-6 times compared to the periodic angle set at the same contrast and spatial resolution.
二维阵列的三维平面波成象（PWI）已在医学超声中用于超快速容积成象。与二维 PWI 相比，三维 PWI 需要传输更多数量的平面波（PW）来扫描感兴趣的体积，并在横向和垂直方向上实现发射动态聚焦。为了减少给定二维角度范围的 PW 角度数量，通过减轻栅瓣电平，我们提出了两种 PW 角度的非周期性模式：具有均匀径向间隔的同心环和著名的向日葵模式。两种模式都经过验证，可提供无规则周期性的均匀角度分布，从而与具有相同 PW 角度数量的周期性角度分布相比降低栅瓣电平。模拟研究表明，与周期性角度集相比，非周期性角度集在所有深度上可将 B 模式图像的对比度提高约 3-6dB。这种增强意味着与相同对比度和空间分辨率的周期性角度集相比，非周期性角度集可以将体积率提高约 2-6 倍。
