空化效应对高强度聚焦超声产生的组织损伤的影响

Cavitation Effect on Tissue Lesion Caused by HIFU

高强度聚焦超声(High intensity focused ultrasound,HIFU)已在临床治疗肿瘤领域展示了较好的应用前景,但目前的治疗计划中未考虑空化效应的影响。本文通过离体实验研究了空化效应对HIFU治疗中组织损伤形成的影响。首先采用KZK非线性方程和Pennes生物传热模型,在理论上模拟了不同超声激励参数的HIFU热效应产生的组织损伤。然后在实验中改变脉冲长度和声压,比较了实验和理论上产生的损伤形成。最后采用B型成像系统定量监测产生的声空化,从而定量分析空化效应对损伤形成的影响,为HIFU治疗策略的设计提供更好的指导。

Promising application of high intensity focused ultrasound(HIFU)has been shown in the field of clinical treatment of tumors,but the effects of cavitation have not been considered in current treatment plans.In this paper,the impact of cavitation effects on the tissue lesion in HIFU therapy in vitro is discussed.Firstly,the KZK nonlinear equation and the Pennes biological heat transfer model are used to theoretically simulate the tissue lesion caused by the HIFU thermal effect with different ultrasonic excitation parameters.Then in the experiments,we change the pulse lengths and sound pressures to compare the tissue lesion experimentally and theoretically.Finally the B-type imaging system is used to quantitatively monitor acoustic cavitation,so as to quantitatively analyze the effects of cavitation on the tissue lesion,thus providing better guidance for the design of HIFU treatment.