Acoustic radiation force in vivo:: A mechanism to assist targeting of microbubbles
Acoustic radiation force in vivo:: A mechanism to assist targeting of microbubbles
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DOI：
10.1016/s0301-5629(99)00062-9
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发表时间：
1999-10-01
影响因子：
2.9
通讯作者：
Ferrara, K
中科院分区：
文献类型：
--
作者：
Dayton, P;Klibanov, A;Ferrara, K
靶向成像的目标是产生生理过程或病理组织成分的增强视图。造影剂可以通过选择性靶向来提高成像方式的特异性，这在使用超声 (US) 对炎症过程或血栓进行成像时尤其重要。选择性靶向的一种方法涉及使用特异性结合机制将造影剂附着到所需部位。由于分子结合机制在纳米量级的距离内有效，因此如果药剂最初集中在特定区域，并且如果药剂在通过潜在结合位点时速度降低，则超声波传输会产生初级辐射力，可以通过每个声脉冲操纵微泡。观察表明，初级辐射力可以将超声造影剂从流线中心转移到体外 200 毫米纤维素容器的壁上。在此，首次提出了辐射力对体内造影剂的影响，实验结果表明，辐射力可以将造影剂移位到小鼠提睾肌中50毫米血管壁上，可以显着降低造影剂的流动速度，并可以产生可逆的聚集。声辐射力提供了一种将造影剂定位和集中在血管壁附近的方法，这可以帮助靶向试剂的输送。 (C) 1999 年世界超声医学与生物学联合会。
(T)he goal of targeted imaging is to produce an enhanced view of physiological processes or pathological tissue components. Contrast agents may improve the specificity of imaging modalities through selective targeting, and this may be particularly significant when using ultrasound (US) to image inflammatory processes or thrombi, One means of selective targeting involves the attachment of contrast agents to the desired site with the use of a specific binding mechanism. Because molecular binding mechanisms are effective over distances on the order of nanometers, targeting effectiveness would be greatly increased if the agent is initially concentrated in a particular region, and if the velocity of the agent is decreased as it passes the potential binding site, Ultrasonic transmission produces a primary radiation force that can manipulate microbubbles with each acoustic pulse. Observations demonstrate that primary radiation force can displace US contrast agents from the center of the streamline to the wall of a 200-mm cellulose vessel in vitro. Here, the effects of radiation force on contrast agents in vivo are presented for the first time, Experimental results demonstrate that radiation force can displace a contrast agent to the wall of a 50-mm blood vessel in the mouse cremaster muscle, can significantly reduce the velocity of flowing contrast agents, and can produce a reversible aggregation. Acoustic radiation force presents a means to localize and concentrate contrast agents near a vessel wall, which may assist the delivery of targeted agents. (C) 1999 World Federation for Ultrasound in Medicine & Biology.