多层媒质中声聚焦控制及其用于热疗的分析

Acoustic Focusing Control in Multi-media and Its Analysis for Hyperthermia

基于伪逆算法提出了一种可对多层生物组织中的肿瘤进行声聚焦控制的方法。对一10×10个正方形阵元的相控阵在肿瘤位于不同深度处时产生的声场进行了仿真,同时计算了生物组织内不同时刻的温度分布,并对不同声辐射功率下加热到相同热剂量时的温度分布进行比较。研究结果表明,该方法能快速有效地对不同深度不同尺寸的肿瘤进行准确地声能聚焦控制;声辐射功率越大时,治疗区域中相同等温曲线所围区域较窄;激发频率、声辐射功率及照射时间均相同时,肿瘤在深度较浅位置时治疗区域温度要高,且此区域较粗短,而在较深位置时治疗区域温度相对较低,且此区域变得狭长。

A method based on pseudo inverse algorithm for controlling acoustic focusing of tumor in multilayer biological tissue is presented. The sound field generated by a phased array composed of 10×10 square elements is simulated as tumor is at different depths.By calculating the temperature of different time in biological tissue and comparing the temperature distribution of the same thermal dose under different acoustic radiation power,it is showed that the acoustic energy can be quickly and accurately focused for different tumor in a desired depth using this method. With the increase of acoustic radiation power,the treatment areas corresponding to the same isotherm become narrow;and the treatment region has higher temperature and a tubbiness shape when the tumor is at shallow position,and has relatively lower temperature and narrower region when tumor is in deeper position under the same exciting frequency,acoustic power and hyperthermia time.