Ultrasonic colour flow imaging.
Ultrasonic colour flow imaging.
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超声彩色血流成像。
DOI：
--
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发表时间：
1994
影响因子：
3.5
通讯作者：
P. Wells
中科院分区：
文献类型：
--
作者：
P. Wells
实时超声彩色血流成像，这是第一次被证明是可行的只有大约十年前，已经进入广泛的临床应用。超声波被红细胞群散射。为血液后向散射提供最佳信噪比的超声频率取决于所需的穿透力。从流动的血液反向散射的超声的频率通过多普勒效应而移动。流动的方向可以通过相位正交检测来确定，并且范围选择性可以通过脉冲回波时间延迟测量来提供。多普勒频谱可以通过傅立叶分析来确定。早期的二维和三维血流成像系统使用缓慢的手动扫描;引入了速度彩色编码。实时彩色血流成像首先成为可行的自相关检测时，用于提取多普勒信号。作为一种宽带技术的时域处理也很快被证明是可行的，可用于分析射频脉冲回波波列和二维图像散斑。频域和时域处理都需要有效消除平稳回波。时域方法似乎具有优势，在混叠和覆盖组织中的衰减效应。对于速度和流动扰动，采用了无需参考图例即可解释的颜色编码方案。根据信号功率的颜色编码也被重新引入。三维显示已被证明。在解释彩色血流图像时，重要的是要了解关键系统控制的功能和伪影的来源。可以采用各种策略来增加图像帧速率。需要不断审查业绩衡量和安全问题。超声彩色血流成像有许多进一步发展的机会，包括系统设计的改进，图像显示方法，造影剂的使用和以前未探索的临床问题的解决方案。
Real-time ultrasonic colour flow imaging, which was first demonstrated to be feasible only about a decade ago, has come into widespread clinical use. Ultrasound is scattered by ensembles of red blood cells. The ultrasonic frequency that gives the best signal-to-noise ratio for backscattering from blood depends on the required penetration. The frequency of ultrasound backscattered from flowing blood is shifted by the Doppler effect. The direction of flow can be determined by phase quadrature detection, and range selectivity can be provided by pulse-echo time-delay measurements. The Doppler frequency spectrum can be determined by Fourier analysis. Early two- and three-dimensional flow-imaging systems used slow manual scanning; velocity colour coding was introduced. Real-time colour flow imaging first became feasible when autocorrelation detection was used to extract the Doppler signal. Time-domain processing, which is a broad-band technique, was also soon shown to be practicable, for analysing both radio-frequency pulse-echo wavetrains and two-dimensional image speckle. Frequency- and time-domain processing both require effective cancellation of stationary echoes. The time-domain approach seems to have advantages in relation to both aliasing and the effects of attenuation in overlying tissues. Colour-coding schemes that can be interpreted without the need to refer to keys have been adopted, for both velocity and flow disturbance. Colour coding according to signal power has also been reintroduced. Three-dimensional display has been demonstrated. In interpreting colour flow images, it is important to understand the functions of critical system controls and the origins of artifacts. Various strategies can be adopted to increase the image frame rate. The problems of performance measurement and safety need to be kept under review. There are numerous opportunities for further development of ultrasonic colour flow imaging, including improvements in system design, methods of image display, the use of contrast agents and the solution of previously unexplored clinical problems.
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使用生理弦模型测试超声波脉冲多普勒仪器。
DOI：
10.7863/jum.1990.9.8.429
发表时间：
1990
期刊：
Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine
影响因子：
--
作者：
Phillips,DJ;Hossack,J;Beach,KW;StrandnessJr,DE
通讯作者：
StrandnessJr,DE
二维血流与角度无关的超声实时系统：初始结果。
影响因子：
19.7
作者：
Bohs,LN;Friemel,BH;McDermott,BA;Trahey,GE
通讯作者：
Trahey,GE
DOI：
10.7863/jum.1989.8.8.425
发表时间：
1989
期刊：
Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine
影响因子：
--
作者：
Yuan,YW;Shung,KK
通讯作者：
Shung,KK
影响因子：
2.9
作者：
BOHS, LN;FRIEMEL, BH;TRAHEY, GE
通讯作者：
TRAHEY, GE