A new active cavitation mapping technique for pulsed HIFU applications--bubble Doppler.
A new active cavitation mapping technique for pulsed HIFU applications--bubble Doppler.
复制标题
DOI：
10.1109/tuffc.2014.006502
复制
发表时间：
2014-10
期刊：
影响因子：
--
通讯作者：
Hwang JH
中科院分区：
文献类型：
--
作者：
Li T;Khokhlova TD;Sapozhnikov OA;O'Donnell M;Hwang JH
在这项工作中，提出了一种用于脉冲高强度聚焦超声（pHIFU）应用的新型主动空化测绘技术，称为气泡多普勒，并在模拟组织凝胶体模中测试了其可行性。 PHIFU 疗法使用短脉冲，以低脉冲重复频率传递，以引起短暂的气泡活动，已被证明可以增强药物和基因向组织的传递。目前在 PHIFU 治疗期间检测和监测空化活动的黄金标准是被动空化检测 (PCD)，它提供了有关气泡空间分布的最少信息。 B 型成像可以检测超回声的形成，但灵敏度非常有限，尤其是对于微小的瞬态微泡。这里提出的气泡多普勒方法基于先前为超声造影剂成像而开发的三种多普勒技术的融合——彩色多普勒、脉冲反转多普勒和去相关多普勒。使用三种不同的脉冲序列将多普勒系综脉冲与治疗性 PHIFU 脉冲交织在一起，并对接收到的回波应用标准多普勒处理。分别评估了每种技术产生的有关 PHIFU 引起的空化气泡的分布和特征的信息，并发现这些信息是互补的。随后提出了统一的方法——气泡多普勒——既可以在空间上绘制瞬态气泡的存在图，也可以估计它们的大小和非线性程度。
In this work, a new active cavitation mapping technique for pulsed high-intensity focused ultrasound (pHIFU) applications termed bubble Doppler is proposed and its feasibility tested in tissue-mimicking gel phantoms. pHIFU therapy uses short pulses, delivered at low pulse repetition frequency, to cause transient bubble activity that has been shown to enhance drug and gene delivery to tissues. The current gold standard for detecting and monitoring cavitation activity during pHIFU treatments is passive cavitation detection (PCD), which provides minimal information on the spatial distribution of the bubbles. B-mode imaging can detect hyperecho formation, but has very limited sensitivity, especially to small, transient microbubbles. The bubble Doppler method proposed here is based on a fusion of the adaptations of three Doppler techniques that had been previously developed for imaging of ultrasound contrast agents – color Doppler, pulse inversion Doppler, and decorrelation Doppler. Doppler ensemble pulses were interleaved with therapeutic pHIFU pulses using three different pulse sequences and standard Doppler processing was applied to the received echoes. The information yielded by each of the techniques on the distribution and characteristics of pHIFU-induced cavitation bubbles was evaluated separately, and found to be complementary. The unified approach - bubble Doppler – was then proposed to both spatially map the presence of transient bubbles and to estimate their sizes and the degree of nonlinearity.