经颅聚焦超声联合微泡开放血脑屏障的数值仿真研究  

Numerical simulation of transcranial focused ultrasound combining microbubble-induced blood-brain barrier opening

作　　者：潘婷 孙天宇 张艳秋 张默涵 凌子超 菅喜岐 PAN Ting;SUN Tianyu;ZHANG Yanqiu;ZHANG Mohan;LING Zichao;JIAN Xiqi(Department of Biomedical Engineering and Technology,Tianjin Medical University,Tianjin 300070,China)

机构地区：[1]天津医科大学生物医学工程与技术学院,天津300070

出　　处：《应用声学》2021年第6期843-855,共13页Journal of Applied Acoustics

摘　　要：近年大鼠等动物实验表明经颅聚焦超声联合微泡技术可无创开放血脑屏障实现药物递送,但在临床治疗时由于人体头颅非均质结构及其高声衰减特性,需优化超声经颅聚焦参数和微泡参数。该文基于人头颅CT数据、82阵元相控换能器和血管建立了三维数值仿真模型,研究超声及微泡参数对机械指数和靶区声发射的影响,评估血脑屏障开放程度及组织损伤的可能性。结果表明,声功率和微泡初始密度增大,机械指数和宽带噪声强度增大;频率增大,稳态空化强度增大;当微泡初始半径大于5μm时,稳态空化显著增强。该研究结果为经颅聚焦超声联合微泡技术诱导可控的血脑屏障开放及安全有效递送治疗药物提供了理论数据和技术参考。In recent years,animal experiments such as rats have shown that the combination of transcranial focused ultrasound and microbubbles enables to non-invasively open the blood-brain barrier for brain-targeted drug delivery.However,due to the nonhomogeneous structure of the human head and its high acoustic attenuation characteristics,it is necessary to optimize the ultrasound transcranial focusing parameters and microbubbles parameters when used in clinical treatment.In this paper,a three-dimensional numerical simulation model is established based on human head CT data,an 82-element phase-controlled transducer and blood vessel to study the effects of ultrasound and microbubbles parameters on mechanical index and acoustic emission of the target area,and to evaluate the degree of the blood-brain barrier opening and the possibility of tissue damage.The results show that the mechanical index and broadband noise intensity increase with the increase of sound power and initial density of microbubbles;the stable cavitation intensity increases with the increase of frequency;when the initial radii of the microbubbles are greater than 5μm,the stable cavitation is significantly enhanced.The results of this study provide theoretical data and technical reference for the induction of controllable blood-brain barrier opening by transcranial focused ultrasound combined with microbubbles and the safe and effective delivery of therapeutic drugs.

关 键 词：血脑屏障 经颅聚焦超声 微泡 机械指数 声发射 

分 类 号：R454.3[医药卫生—治疗学]