Institut Langevin, ESPCI ParisTech, PSL Research University, CNRS UMR7587, INSERM U979, 17 rue Moreau, 75012 Paris, France.
Phys Med Biol. 2018 Oct 24;63(21):215012. doi: 10.1088/1361-6560/aae427.
Four-dimensional (4D) Ultrafast ultrasound imaging was recently proposed to image and quantify blood flow with high sensitivity in 3D as well as anatomical, mechanical or functional information. In 4D Ultrafast imaging, coherent compounding of tilted planes waves emitted by a 2D matrix array were used to image the medium at high volume rate. 4D ultrafast imaging, however, requires a high channel count (>1000) to drive those probes. Alternative approaches have been proposed and investigated to efficiently reduce the density of elements, such as sparse or under-sampled arrays while maintaining a decent image quality and high volume rate. The row-columns configuration presents the advantage of keeping a large active surface with a low amount of elements and a simple geometry. In this study, we investigate the row and column addressed (RCA) approach with the orthogonal plane wave (OPW) compounding strategy using real hardware limitations. We designed and built a large 7 MHz 128 + 128 probe dedicated to vascular imaging and connected to a 256-channel scanner to implement the OPW imaging scheme. Using this strategy, we demonstrate that 4D ultrafast Power Doppler imaging of a large volume of [Formula: see text] up to [Formula: see text] depth, both in vitro on flow phantoms and in vivo on the carotid artery of a healthy volunteer at a volume rate of 834 Hz.
四维(4D)超快超声成像是近年来提出的一种技术,用于以高灵敏度在 3D 中成像和量化血流,同时提供解剖学、力学或功能信息。在 4D 超快成像中,使用二维矩阵阵列发射的倾斜平面波相干复合来以高体积率对介质进行成像。然而,4D 超快成像需要高通道计数(>1000)来驱动这些探头。已经提出并研究了替代方法来有效地降低元素密度,例如稀疏或欠采样阵列,同时保持良好的图像质量和高体积率。行-列配置具有保持大有源表面、低元件数量和简单几何形状的优势。在这项研究中,我们使用真实硬件限制研究了行和列寻址(RCA)方法与正交平面波(OPW)复合策略。我们设计并构建了一个大型的 7MHz 128+128 探头,专门用于血管成像,并连接到一个 256 通道的扫描仪来实现 OPW 成像方案。使用这种策略,我们证明了在体外流幻影和在健康志愿者的颈动脉中的体内实验中,能够以 834Hz 的体积率对[Formula: see text]体积高达[Formula: see text]深度进行 4D 超快功率多普勒成像。