自聚焦超声在动物离体皮下脂肪组织中的融脂效应研究

Lipolysis effect induced by self-focusing ultrasound on in vitro animal adipose tissue

目的:探索高频聚焦超声和低频聚焦超声在不同辐照时间和功率的条件下,对离体动物猪的皮下脂肪不同层产生生物学融脂效应的规律。方法:将离体动物猪脂肪生物实验分为两组,分别使用工作频率为6.5 MHz和3 MHz的换能器。两组使用的超声功率为2~5 W,辐射时间为5 s、10s、20s、4s、60s和80s;辐照后进行MTT检测脂肪细胞活性并计算融脂效应的面积。描述离体动物猪的皮下脂肪层生物学融脂效应,讨论不同条件下生物学融脂效应之间的区别。结果:随着超声功率和辐照时间的增加,脂肪组织形成融脂效应的程度呈规律性变化。辐照时间为5 s时脂肪组织破坏不明显,辐照时间>10s时脂肪组织则明显被破坏。相同超声功率和辐射时间条件下聚焦超声在深脂肪层的破坏程度比浅表脂肪层高。3MHz聚焦超声在辐射时间≥40s可穿过约5mm的表皮并凝固性破坏皮下不同层次的脂肪组织。结论:高频和低频聚焦超声均可有效破坏脂肪组织。

Objective： To explore the biological effect of high frequency ultrasound and low frequency ultrasound on different layers in vitro swine adipose tissue. Methods： In vitro experiment was divided into two groups with working frequency of transducers being 6.5 MHz and 3MHz. In 6.5MHz group, ultrasonic power 2-5W and irradiation time 5, 10, 20, 40, 60 and SOs were adopted and cell activity was determined through MTF staining method and thus the area of coal^ulation necrosis was calculated. In 3 MHz group, biological effect induced by iocusecl-ultrasoun-cton different layers of the swine adipose tissue was observed and the difference in result was discussed under same experiment parameters. Results： Lipolysis effect changes in an order with increasing ultrasonic power and irradiation time. 5s irradiation time shows no obvious damage to the tissue, however shows obvious damage above 10s. Under the same experiment parameters, deep adipose tissue （DAT） shows higher level of tissue damage than superficial adipose tissue（SAT）. Only 3 MHz frequency can pass through the skin of thickness 5mm at irradiation time≥40s. Conclusion： Both high and low frequency ultrasound can effectively destroy adipose tissue.