Fast Vascular Ultrasound Imaging With Enhanced Spatial Resolution and Background Rejection
Fast Vascular Ultrasound Imaging With Enhanced Spatial Resolution and Background Rejection
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DOI：
10.1109/tmi.2016.2600372
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发表时间：
2017-01-01
影响因子：
10.6
通讯作者：
Eldar, Yonina C.
中科院分区：
文献类型：
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作者：
Bar-Zion, Avinoam;Tremblay-Darveau, Charles;Eldar, Yonina C.
超声超定位显微镜技术在过去几年中提出，使非侵入性成像的血管结构在毛细血管水平通过跟踪超声造影剂（气体微泡）的流动。然而，这些技术目前受到时间分辨率低和采集时间长的限制。超分辨率光学起伏成像（SOFI）是一种通过计算起伏光学信号的高阶统计量实现具有高时间分辨率的亚衍射极限成像的荧光显微技术。这项工作的目的是实现快速声学成像与增强分辨率的应用工具，在SOFI对比增强超声（CEUS）平面波扫描。所提出的方法进行了测试，使用数值模拟和评估使用两个体内兔模型：健康肾脏和VX-2肿瘤异种移植物的扫描。观察到空间分辨率的提高，点扩散函数的半峰全宽降低了50%。此外，与标准平均振幅持续图像相比，实现了背景水平的大幅降低，揭示了肿瘤内的小血管结构。所提出的方法的扫描持续时间小于一秒，而当前的超定位技术需要几分钟的采集持续时间。因此，所提出的技术可用于获得具有增强的空间分辨率和高时间分辨率的扫描，从而促进流动动力学监测。我们的方法也可以在屏气期间应用，降低对运动伪影的敏感度。
Ultrasound super-localization microscopy techniques presented in the last few years enable non-invasive imaging of vascular structures at the capillary level by tracking the flow of ultrasound contrast agents (gas microbubbles). However, these techniques are currently limited by low temporal resolution and long acquisition times. Super-resolution optical fluctuation imaging (SOFI) is a fluorescence microscopy technique enabling sub-diffraction limit imaging with high temporal resolution by calculating high order statistics of the fluctuating optical signal. The aim of this work is to achieve fast acoustic imaging with enhanced resolution by applying the tools used in SOFI to contrast-enhance ultrasound (CEUS) plane-wave scans. The proposed method was tested using numerical simulations and evaluated using two in-vivo rabbit models: scans of healthy kidneys and VX-2 tumor xenografts. Improved spatial resolution was observed with a reduction of up to 50% in the full width half max of the point spread function. In addition, substantial reduction in the background level was achieved compared to standard mean amplitude persistence images, revealing small vascular structures within tumors. The scan duration of the proposed method is less than a second while current super-localization techniques require acquisition duration of several minutes. As a result, the proposed technique may be used to obtain scans with enhanced spatial resolution and high temporal resolution, facilitating flow-dynamics monitoring. Our method can also be applied during a breath-hold, reducing the sensitivity to motion artifacts.