Ultrafast 3D Ultrasound Localization Microscopy Using a 32 x 32 Matrix Array
Ultrafast 3D Ultrasound Localization Microscopy Using a 32 x 32 Matrix Array
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DOI：
10.1109/tmi.2018.2890358
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发表时间：
2019-09-01
影响因子：
10.6
通讯作者：
Couture, Olivier
中科院分区：
文献类型：
--
作者：
Heiles, Baptiste;Correia, Mafalda;Couture, Olivier
超声定位显微镜通过定位微泡，可以以远小于波长的分辨率绘制血管图。目前该技术的实现仅限于二维平面或三维小视场。它们遭受了几分钟的采集，面外微泡和组织运动。在本文中，我们利用最近发展的四维超快超声成像，对各向同性体积进行每秒高达20,000次的失谐，并在三维上进行定位显微镜。具体来说，一个32 x 32单元，9 mhz矩阵阵列探针连接到一个1024通道可编程超声扫描仪，用于实现复杂3D结构（主通道分支成两个侧通道）的结构和矢量流的亚波长体积成像。为了解决大体积气泡的三维定位问题，提出了一种基于波束形成微气泡信号的反卷积算法。为了跟踪，单个粒子按照Munkres分配方法配对，速度测量按照拉格朗日方法完成。ULM能够清晰地描绘运河边缘（小至230亩）的结构的三维形状，并以低至52亩的间距将它们分开。500 Hz的复合体积率足以描述2.5-150毫米/秒的速度，并将最大采集时间缩短至12秒。本文论证了体外三维超快超声定位显微镜的可行性，为体内体积定位显微镜的研究开辟了道路。
Ultrasound localization microscopy can map blood vessels with a resolution much smaller than the wavelength by localizing microbubbles. The current implementations of the technique are limited to 2-D planes or small fields of view in 3-D. These suffer from minute-long acquisitions, out-of-plane microbubbles, and tissue motion. In this paper, we exploit the recent development of 4D ultrafast ultrasound imaging to insonify an isotropic volume up to 20 000 times per second and perform localization microscopy in the three dimensions. Specifically, a 32 x 32 elements, 9-MHz matrix-array probe connected to a 1024-channel programmable ultrasound scanner was used to achieve sub-wavelength volumetric imaging of both the structure and vector flow of a complex 3D structure (a main canal branching out into two side canals). To cope with the large volumes and the need to localize the bubbles in the three dimensions, novel algorithms were developed based on deconvolution of the beamformed microbubble signal. For tracking, individual particles were paired following a Munkres assignment method, and velocimetry was done following a Lagrangian approach. ULM was able to clearly represent the 3-D shape of the structure with a sharp delineation of canal edges (as small as 230 mu m) and separate them with a spacing as low as 52 mu m. The compounded volume rate of 500 Hz was sufficient to describe velocities in 2.5-150-mm/s range and to reduce the maximum acquisition time to 12 s. This paper demonstrates the feasibility of in vitro 3-D ultrafast ultrasound localization microscopy and opens up the way toward in vivo volumetric ULM.