摘要
目的:超声微泡造影剂经历了不同的技术发展阶段,目前靶向微泡造影剂的应用是一个重要的研究领域。方法:超声微泡造影剂可分为普通型和特殊型两类。普通超声造影剂经历了三个发展阶段,第一代为内含空气的气泡,无包膜且尺寸大;第二代内含空气,有膜包被,尺寸小;第三代内含氟碳类气体,有稳定的膜壳。靶向微泡造影剂是一类特殊造影剂,最新研究用于超声-微泡介导的靶向分子成像,如血栓、炎症显影,还可用于溶栓治疗,靶向药物或基因治疗等方面。结果:超声造影剂的稳定性不断提高,靶向微泡造影剂经静脉注射可到达特定靶区,低能超声作用下可提高局部组织显影的分辨率。携带治疗药物或基因的靶向微泡造影剂在低频(1MHz)超声作用下产生瞬态空化效应,细胞膜的通透性增加,因而有效提高了药物或基因的转染率。结论:超声联合靶向微泡技术在临床诊断和治疗中显示出了较大的优势,但其确切的生物学机制还未清楚,超声治疗参数需进一步优化。
Objective： Several generations of ultrasound contrast agents have been developed. Now the application of targeted microbubble is an important research field. Methods： Ultrasound microbubble contrast agents can be divided into two types： ordinary and special ones. First generation microbubble products are air bubbles. They lack a stabilizing shell and have large size. The second ones are stabilized by a shell and have a smaller size ,instable gas cores consisting of air. The third ones have a stable shell and gas cores with perfluorocarbons. Researches on new applications of targeted microbubble involve the targeted molecular imaging such as tbrombus and inflammation imaging, thrombolytic therapy, drug/gene therapy and so on. Results： The stability of microbubble is increased gradually. Microbubble is injected intravenously and reaches the targeted tissue. At low ultrasound beam power imaging contrast can be improved. Low frequency ultrasound （I MHz） can cause transient perfora- tion of cell membrane by cavitation effects and thereby improve drug/gene delivery efficiency. Conclusions： Ullrasound-target- ed microbubble has shown its advantages over other methods in the clinical diagnosis and treatment. While the bio-effects are not fully understood. And physical parameters affecting drug or gene delivery efficiency should be optimized.
出处
《中国医学物理学杂志》
CSCD
2010年第2期1802-1805,共4页
Chinese Journal of Medical Physics
基金
上海市科委项目(No.0752nm027)
关键词
超声造影剂
微泡
靶向
分子成像
治疗
ultrasound contrast agents
microbubble
targeted
molecular imaging
therapy
