摘要
目的探讨采用改进声学参数的超声治疗仪激励循环微泡空化，延长正常兔肝血流阻断时间的可行性。方法改进型脉冲式超声空化治疗仪，治疗头频率831kHz，峰值负压4．3MPa，平均声强1．25W／cm^2。9只新西兰大白兔麻醉后开腹暴露肝，经耳缘静脉缓慢推注微泡的同时予以超声辐照肝5min；其中6只分别于治疗前、治疗后即刻、30min、60min及48h对治疗靶区行超声造影，视觉观察并用声学密度方法测量各时间点峰值强度（PI）变化；其余3只用于治疗后即刻病理学检查。结果治疗前肝实质造影增强显著并且均匀，PI为（-51．88±4．26）dB，治疗后即刻靶区PI降至（-62．53±4．83）dB，视觉观察血流灌注几乎完全消失，30-60min后肝血流灌注呈缓慢恢复，48h后几乎恢复正常，PI为（-52．00±4．60）dB。治疗后即刻、30min、60min肝实质平均PI低于治疗前及治疗后48h，差异均有统计学意义（P〈0．05），治疗前与治疗后48h差异无统计学意义（P〉0．05）。光镜下可见肝细胞弥漫性混浊肿胀，挤压肝窦及窦状间隙；门静脉周围出血、血肿形成。结论超声联合微泡可以阻断正常兔肝的血流灌注达1h，其阻断机制可能主要是肝细胞肿胀。
Objective To explore the feasibility of extending liver blood perfusion cessation by ultrasound combining microbubbles. Methods The livers of 9 healthy rabbits were treated with a pulsed therapeutic ultrasound device, in presence of microbubbles. For quantification of liver perfusion, contrastenhanced ultrasonography was performed on 6 rabbits before treatment and at different time points of 0 min,30 min, 60 min and 48 hours after treatment. Pathological examination of the treated livers was performed immediately after treatment on the other 3 rabbits. Results The liver blood perfusion almost vanished immediately after treatment,remained at a low perfusion level from 30 to 60 min,and completely recovered 48 hours later. The peak intensity dropped from （ - 51.88 ± 4.26）dB to （ - 62.53± 4.83）dB after treatment and rose up to （ - 52.00± 4.60） dB 48 hours later. The peak intensities before treatment and 48 hours after treatment were significantly higher than those of 0 min, 30 min and 60 min time points after treatment（ P 〈0.05）. Pathological examination showed significant swelling of hepatocytes and hemorrhage around portal veins. Conclusions Microbubbles enhanced ultrasound can induce liver blood perfusion cessation for up to 1 hours. The mechanism could be swelling of hepatocytes and hemorrhage of portal track.
出处
《中华超声影像学杂志》
CSCD
北大核心
2011年第11期988-991,共4页
Chinese Journal of Ultrasonography
基金
重庆市科技攻关计划（重点）项目（cstc2011ggB10002）
国家自然科学基金资助项目（30672014）
关键词
超声检查
微气泡
肝
空化效应
Ultrasonography
Microbubbles
Liver
Cavitation
