IEEE Trans Ultrason Ferroelectr Freq Control. 2017 Apr;64(4):648-659. doi: 10.1109/TUFFC.2017.2651498. Epub 2017 Jan 10.
Today's 3-D cardiac ultrasound imaging systems suffer from relatively low spatial and temporal resolution, limiting their applicability in daily clinical practice. To address this problem, 3-D diverging wave imaging with spatial coherent compounding (DWC) as well as 3-D multiline-transmit (MLT) imaging have recently been proposed. Currently, the former improves the temporal resolution significantly at the expense of image quality and the risk of introducing motion artifacts, whereas the latter only provides a moderate gain in volume rate but mostly preserves quality. In this paper, a new technique for real-time volumetric cardiac imaging is proposed by combining the strengths of both approaches. Hereto, multiple planar (i.e., 2-D) diverging waves are simultaneously transmitted in order to scan the 3-D volume, i.e., multiplane transmit (MPT) beamforming. The performance of a 3MPT imaging system was contrasted to that of a 3-D DWC system and that of a 3-D MLT system by computer simulations during both static and moving conditions of the target structures while operating at similar volume rate. It was demonstrated that for stationary targets, the 3MPT imaging system was competitive with both the 3-D DWC and 3-D MLT systems in terms of spatial resolution and sidelobe levels (i.e., image quality). However, for moving targets, the image quality quickly deteriorated for the 3-D DWC systems while it remained stable for the 3MPT system while operating at twice the volume rate of the 3-D-MLT system. The proposed MPT beamforming approach was thus demonstrated to be feasible and competitive to state-of-the-art methodologies.
今天的 3-D 心脏超声成像系统存在相对较低的空间和时间分辨率的问题，限制了它们在日常临床实践中的应用。为了解决这个问题，最近提出了 3-D 发散波成像与空间相干复合（DWC）以及 3-D 多线发射（MLT）成像。目前，前者以牺牲图像质量和引入运动伪影的风险为代价，显著提高了时间分辨率，而后者仅提供了中等的容积率增益，但主要保留了质量。在本文中，提出了一种新的实时容积心脏成像技术，该技术结合了两种方法的优点。为此，同时发射多个平面（即 2-D）发散波，以扫描 3-D 体积，即多平面发射（MPT）波束形成。通过计算机模拟，在目标结构处于静止和运动状态下，对 3-MPT 成像系统的性能与 3-D DWC 系统和 3-D MLT 系统进行了对比，同时在相似的容积率下运行。结果表明，对于静止目标，3-MPT 成像系统在空间分辨率和旁瓣水平（即图像质量）方面与 3-D DWC 和 3-D MLT 系统具有竞争力。然而，对于运动目标，3-D DWC 系统的图像质量迅速恶化，而 3-MPT 系统则保持稳定，同时以 3-D-MLT 系统两倍的容积率运行。因此，所提出的 MPT 波束形成方法被证明是可行的，并且与最先进的方法具有竞争力。
