聚焦超声辐照仿组织体模过程中实时气泡活动及其对损伤的影响
发布时间：2019-07-09 07:00
【摘要】：目的探讨聚焦超声辐照仿组织体模过程中沸腾气泡和空化气泡的演变及其对损伤的影响。方法以聚焦超声辐照仿组织体模30 s。采用连接在体视显微镜上的高速摄影机实时监控辐照过程中的气泡活动和损伤演变,同时进行被动空化检测。在相同条件下分别重复8次实验。结果在沸腾气泡产生前,未见宽带噪声增加,损伤同时向声源方向和远离声源方向呈"雪茄"状线性增长;毫米级沸腾气泡瞬时产生后,迅速破裂成大量微米级气泡,而后宽带噪声出现阶跃性增强并持续至辐照结束,同时损伤范围快速增大并向声源方向发展,形状由"雪茄"状变为"蝌蚪"状;沸腾气泡完全破裂时间[(9.79±1.86)s]与3~7 MHz宽带噪声出现阶跃性增强的时间[(9.75±2.84)s]差异无统计学意义(P0.05)。结论毫米级沸腾气泡破裂成大量微米级气泡后为空化提供了空化核,也成为损伤向声源方向前移、范围快速非线性增大及损伤形状由"雪茄"状变为"蝌蚪"状的原因。
[Abstract]:Objective to investigate the evolution of boiling bubbles and cavitation bubbles and their effect on damage during focused ultrasound irradiation of tissue-like phantom. Methods the tissue phantom was irradiated by focused ultrasound for 30 s. A high speed camera connected to stereoscopic microscope is used to monitor bubble activity and damage evolution in real time during irradiation, and passive cavitation detection is carried out at the same time. Eight experiments were repeated under the same conditions. Results before the generation of boiling bubbles, there was no increase in broadband noise, and the damage increased linearly in the direction of sound source and away from the sound source at the same time. After the instantaneous generation of millimeter boiling bubble, it burst into a large number of micron bubbles, and then the broadband noise increased step by step and lasted until the end of irradiation, at the same time, the damage range increased rapidly and developed in the direction of sound source, and the shape changed from "cigar" to "tadpole". There was no significant difference between the complete rupture time of boiling bubbles [(9.79 卤1.86) s] and the time of step enhancement of 3 鈮，
本文编号：2511952
[Abstract]:Objective to investigate the evolution of boiling bubbles and cavitation bubbles and their effect on damage during focused ultrasound irradiation of tissue-like phantom. Methods the tissue phantom was irradiated by focused ultrasound for 30 s. A high speed camera connected to stereoscopic microscope is used to monitor bubble activity and damage evolution in real time during irradiation, and passive cavitation detection is carried out at the same time. Eight experiments were repeated under the same conditions. Results before the generation of boiling bubbles, there was no increase in broadband noise, and the damage increased linearly in the direction of sound source and away from the sound source at the same time. After the instantaneous generation of millimeter boiling bubble, it burst into a large number of micron bubbles, and then the broadband noise increased step by step and lasted until the end of irradiation, at the same time, the damage range increased rapidly and developed in the direction of sound source, and the shape changed from "cigar" to "tadpole". There was no significant difference between the complete rupture time of boiling bubbles [(9.79 卤1.86) s] and the time of step enhancement of 3 鈮，
本文编号：2511952
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