On the effect of lung filtering and cardiac pressure on the standard properties of ultrasound contrast agent
On the effect of lung filtering and cardiac pressure on the standard properties of ultrasound contrast agent
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DOI：
10.1016/s0041-624x(97)00137-6
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发表时间：
1998-02-01
期刊：
影响因子：
4.2
通讯作者：
Jouini, K
中科院分区：
文献类型：
--
作者：
Bouakaz, A;de Jong, N;Jouini, K
超声心动图造影的目标标准是使用造影剂对心肌灌注进行绝对测量。实际上，已经开发了几种造影剂。所有这些药物在静脉注射后均显示出左心室混浊。然而，使用传统成像技术时，这些药物均未显示出可接受的心肌增强作用。通过测量造影剂的声学特性，然后将这些特性与心肌的声学特性进行比较，应该很容易解释这种现象。在本研究中，我们提出了超声造影剂的标准声学参数、后向散射系数 B-s 和散射衰减比 STAR 的定义。然后，考虑静脉注射造影剂，并考虑肺滤过和心脏压力的影响，在不同部位确定造影剂的标准特性：右心室（肺通过之前）、左心室（肺通过之后并考虑压力影响）和冠状系统。计算表明，声学特性很大程度上受到肺过滤和心脏压力这两种效应的影响。然后将这些特性与组织特性（心肌）进行比较。这决定了造影剂对增强组织可视化的贡献。模拟是在 Albunex 微球上进行的。结果表明，心肌的散射与静脉注射的 Albunex 的散射之间的差异太小，在回波描记图像上无法看到。 (C) 1998 Elsevier Science B.V.
The goal standard of contrast echocardiography is the absolute measure of myocardial perfusion using a contrast agent. Actually, several contrast agents are developed. All these agents show left ventricular opacification after intravenous injection. However, none of these agents shows an acceptable enhancement of the myocardium yet using conventional imaging techniques. The explanation of this phenomenon should be easy by measuring the acoustic characteristics of the contrast agent and then making a comparison of these characteristics with those of the myocardium.In this study we present definitions of standard acoustic parameters of ultrasound contrast agent, the backscatter coefficient B-s and the scattering-to-attenuation ratio STAR. Afterwards, considering an intravenous injection of the contrast agent, and taking into account the effects of lung filtering and cardiac pressure, the standard properties of contrast agents are determined in different sites: right ventricle (before lung passage), left ventricle (after lung passage and taking into account the pressure effect) and in the coronary system. Calculations showed that the acoustic properties are considerably influenced by these two effects: lung filtering and cardiac pressure. Comparison of these properties with the tissue properties (myocardium) is then performed. This determines the contribution of the contrast agent to the enhancement of the tissue visualization. The simulations are performed on Albunex microspheres. The results reveal that the difference between scattering of the myocardium and scattering of intravenously injected Albunex is too slight to be visible on an echographic image. (C) 1998 Elsevier Science B.V.