B模式实时成像定量监控超声空化时空行为的研究  

Real-time spatiotemporal detection and quantification of ultrasound-induced cavitation activity using B-mode imaging

作　　者：陈楚怡 于洁[1,2] 陈功[2] 马勇[2] 郭霞生[1] 屠娟[1] 章东[1] 

机构地区：[1]南京大学近代声学教育部重点实验室,南京210093 [2]江苏省中医院,南京210023

出　　处：《声学学报》2015年第4期563-568,共6页Acta Acustica

基　　金：国家科技部973计划(2011CB707900);国家自然科学基金资助(81127901;81227004;11074123;11374155;11174141;11274170;61072027;11161120324;11104140);国家科技部863项目(2012AA022702);新世纪优秀人才项目(NCET-11-0236)资助

摘　　要：提出一种采用B超图像实现高强聚焦超声(HIFU)治疗时声空化的时空量化监控的方法。首先,采用B模式实时成像系统对不同声辐照能量下的HIFU在凝胶仿体中引发的超声空化进行实验监测;接着,利用二维数字图像处理算法消除高强聚焦超声(HIFU)在B超图像中产生的干涉条纹,并在此基础上,对B超成像中观察到的高亮区域的面积变化情况进行量化分析;最后,进一步讨论了驱动声压或脉冲宽度对超声空化产生的高亮区域的生成速度和面积大小的影响。结果显示该方法可以有效去除B超图像中的干涉条纹,并对HIFU引发的空化现象进行实时监测。实验结果还表明辐照声能量的提高将引发更强烈的声空化行为,并且显著缩短HIFU引发的空化泡群的初始生成时间。研究结果对进一步优化HIFU治疗有重要意义。Cavitation activities induced by high intensity focused ultrasound （HIFU） pulses were detected and quan- tiffed in vitro, based on area measurements of hyperechoic regions observed in B-mode ultrasound images. A two dimensional imaging processing algorithm was proposed to eliminate the moving interference bands in B-mode images. The temporal evolution of bubble clouds, generated by HIFU exposures with constant working frequency and pulse rep- etition frequency but varied driving pressures and pulse lengths, were analyzed by measuring time-varying behaviors of hyperechoic region areas recorded in B-mode images. The results show that the proposed imaging processing algorithm is effective to remove the bright interference masks in B-mode image, which makes HIFU-induced cavitation bubble clouds can be monitored and evaluated by B-mode imaging in real-time. With the increasing acoustic energy deposited in the tissue phantom, the hyperechoic region area in B-mode image indicating more violent cavitation activity can be enlarged, while the initial generation time of HIFU-induced cavitation bubbles will be shortened. This study is important for further optimization of HIFU therapy.

关 键 词：超声空化 干涉条纹 实时成像 高强聚焦超声 空化泡 声能量 生成时间 灰度阈值 脉冲宽度 生成速度 

分 类 号：R454.3[医药卫生—治疗学]