低强度聚焦超声靶向爆破微泡  

Targeted microbubbles destruction with low intensity focused ultrasound

作　　者：董桂芳[1] 冉海涛[1,2] 王志刚[1] 宫玉萍[1] 王希[1] 

机构地区：[1]重庆医科大学超声影像学研究所,重庆400010 [2]重庆医科大学附属第二医院超声科,重庆400010

出　　处：《中国介入影像与治疗学》2013年第3期171-174,共4页Chinese Journal of Interventional Imaging and Therapy

基　　金：重庆市科技攻关项目(CSTC;2009AB5216);国家自然科学基金面上项目(81071157)

摘　　要：目的探讨自制低强度聚焦超声(LIFU)体外靶向爆破微泡范围、空间分布,及在兔肝脏组织中应用LIFU辐照载紫杉醇脂质微泡(PLM)的定位控释情况。方法①采用4种不同声强(0.3、0.6、0.9、1.2 W/cm2)LIFU(频率1MHz,焦距160mm,占空比50%)分别辐照含脂质微泡的水囊,同时从不同切面观察并记录水囊内微泡爆破范围及空间分布形态;②选取新西兰大白兔10只,随机平均分为聚焦超声组(A组)和非聚焦超声组(B组);对实验兔静脉注射PLM后,对A、B组分别采用LIFU和非聚焦超声定位辐照肝脏2min;辐照后1h处死实验兔,取焦域中心及距离中心1cm、2cm、3cm处的肝脏组织,采用反相高效液相色谱法测定各肝脏组织内的紫杉醇含量。结果①LIFU体外定位爆破微泡范围局限、形状规则,爆破范围随声强增高而增大;②A组辐照中心处紫杉醇浓度最大,距离中心处越远,紫杉醇浓度越低(F=201.81,P<0.05);B组中各位置紫杉醇浓度的差异无统计学意义(F=1.36,P>0.05);辐照中心处,A组紫杉醇浓度高于B组(t=5.28,P<0.05)。结论 LIFU能够实现体内外靶向爆破微泡,其聚焦部位和微泡爆破范围可调。Objective To explore the destruction range and space distribution of microbubbles using low power focused ultrasound （LIFU）, and to observe the targeted destruction using paclitaxel-carrying liposome microbubbles （PLM） and LIFU in the liver of rabbits. Methods ①The bladder containing lipid microbubbles was irradiated with 4 different intensities of LIFU （0.3, 0.6, 0.9, 1.2 W/cm2）, and the destruction ranges and spatial distribution shapes of the microbubbles in the bladder were observed and recorded from different facets. ②Ten rabbits were randomly divided into focused ultrasound group （group A, n=5） and focused ultrasound group （group B, n=5）. After injection of PLM, rabbits in group A and B were irradiated respectively with LIFU and non-focused ultrasound at the liver for 2 min. The rabbits were sacrificed after 1 h, and the liver tissue at the center of the focal region and 1 cm, 2 cm, 3 cm from the center were harvested. The paclitaxel concentration was measured with reversed-phase high-performance liquid chromatography. Results ①LIFU could destruct microbubbles in a specific position, and the ranges were limited and increased with the increase of intensities. ②In group A, paclitaxel concentration at the center was the highest, and drug concentration decreased with the increase of distance from the center （F=201.81, P〈0.05）. There was no significant difference of drug concentration at different distances in group B （F=1.36, P〉0.05）. The paclitaxel concentration at the center in group A was higher than that in group B （t=5.28, P〈0.05）. Conclusion LIFU can target microbubbles destruction, and its focused sites and microbubbles destruction ranges are adjustable.

关 键 词：低强度聚焦超声 靶向 爆破 定位 

分 类 号：R445.1[医药卫生—影像医学与核医学] R-332[医药卫生—诊断学]