电容射频热疗中引入内电极对深部热场分布影响的仿真研究

深部热场控制是电容射频热疗用于深部治癌时尚未能有效解决的难点。本文研究了引人内部电极（接地域接极板）对电容射频（１３．５６ＭＨｚ）热疗深部热场的比吸收率（ＳＡＲ）和程度分布影响。模拟计算表明：引入内电极将显著改变深部热场分布，使８０％以上的ＳＡＲ集中于该电极周围，并使内电极附近成为温度最高的热点；调整内电极位置和加电方式可有效地控制深区ＳＡＲ和温度分布形态，可为深部肿瘤热疗提供新的加热方法。

STUDY ON INFLUENCES UPON SAR AND TEMPERATURE DISTRIBUTIONS AT THE DEEP REGION BY INSERTING AN INNER ELECTRODE DURING CAPACITIVE RADIO-FREQUENCY HYPERTHERMIA

An inner electrode connected to earth (or to one capacitive electrode) was used to improve the deep heat distributions in the radiofrequency capacitive hyperthermic system. The 2D SAR and temperature distribution patterns in muscle tissue were calculated with the inner electrode. The simulated results showed that the main heating field (enclosed by the 50% SAR contour) and the heavily heated region (enclosed by the 80% SAR contour and the highest temperature isothermal) were always around the inner electrode. The deep SAR and temperature distribution patterns were controlable by adjusting the depth of the inner electrode. The method provided a new way for the capacitive radio frequency hyperthermia to treat deep tumor.