Introduction to ultrasound contrast agents: physics overview
Introduction to ultrasound contrast agents: physics overview
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DOI：
10.1007/pl00014069
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发表时间：
1999-01-01
影响因子：
5.9
通讯作者：
Bertolotto, M
中科院分区：
文献类型：
--
作者：
Dalla Palma, L;Bertolotto, M
超声造影剂的使用开辟了全新的视角。这些试剂有望能够对血管结构进行成像，而这些血管结构无法使用非增强型多普勒技术进行评估，即使使用最明智、最新的设备也是如此。多种超声造影剂可商购或目前正在试验中，其成分、作用机制和用途各不相同。然而，微泡和入射超声波束之间的相互作用基本相同。造影剂真正的作用是修改血液回声的特征信号。对于大多数造影剂来说，在非常高的稀释度下，增强比它们是被动反射器时预期的增强要强得多。此外，它取决于超声波频率和微泡尺寸，表明存在共振现象。事实上，微泡充当主动声源，在超声波场中经历振荡，并具有自然共振频率，在该频率下它们可以高效地吸收和散射超声波。本文的目的是从物理角度概述超声场中的微泡行为，强调特定对比成像技术所基于的物理特性。
The use of ultrasound contrast agents opens up totally new perspectives. These agents are expected to allow imaging of vascular structures which cannot be evaluated using non-enhanced Doppler techniques even using the most sensible, newest apparatus. A variety of ultrasound contrast agents are commercially available or currently on trial differing with regard to composition, mechanism of action, and use. However, interaction between microbubbles and the incident ultrasound beam is basically the same. What contrast agents really do is to modify the characteristic signature of the echo from blood.For most contrast agents, in very high dilution, enhancement is much stronger than would be expected if they were passive reflectors. Moreover, it depends on both ultrasound frequency and microbubble size, suggesting resonance phenomena. As a matter of fact, microbubbles behave as an active source of sound, undergo oscillation in the ultrasound field, and have a natural resonance frequency at which they both absorb and scatter ultrasound with high efficiency. The aim of this paper is to overview microbubble behavior in an ultrasound field from the physical point of view highlighting the physical properties on which contrast-specific imaging techniques are based.