A new applicator of RF capacitive heating for head and neck cancer

我们设计了一种新型的涂药器（u型涂药器），将直径为15cm的扁平电极弯曲成u型。日本热疗学会QA模型分别用u型和平型加热器加热。用特氟龙涂层热电偶测量模体内的温度，用热成像仪测量加热后的垂直截面热分布。u型涂敷器减少了不利的边缘效应，获得了良好的热分布。在加热后的热剖面上，扁平涂敷器将最高温度区域移至模体的较浅侧面，u形涂敷器将最高温度区域移至靠近芯的位置。热分布的变化可能不仅是由于边缘效应的减小，而且是由于两电极之间距离的变化。在我们的一名同事的下咽癌患者的临床应用中，u型涂敷器减少了疼痛和其他并发症，并且口底和食管入口的最高温度比扁平涂敷器高了近2个ºC。温度的变化可能是由于边缘效应的减小，电极之间的距离缩短，电极到皮肤的不均匀距离的改善。u型涂抹器有望在临床热疗肿瘤学中发挥重要作用。

We devised a new type of applicator (U-shape applicator), with bending the flat electrode of 15 cm in diameter into U-shape. Japan hyperthermia society QA phantoms were heated with the U-shape applicator and with the flat applicator. The temperature in the phantom was measured with the Teflon coated thermocouples and the vertical sectional thermal distributions after heating were taken with a thermography unit. The untoward edge effect was reduced and favorable thermal distribution was obtained with the U-shape applicator. On the thermal profile after heating, the highest temperature zone was shifted to the shallower sides of the phantom with the flat applicator, and was near the core with the U-shape applicator. The change of the thermal distribution may be not only due to the decrease of the edge effects but the changes of the distance between both electrodes. In the clinical application to one of our co-workers who was suffering hypopharyngeal cancer, pain and other complication were reduced and the maximum temperature of the oral floor and at esophageal inlet was nearly 2ﾟC higher with the U-shape applicator than with the flat applicator. The change of the temperatures may be due to the decrease of the edge effects, the shortening of the distance between both electrodes, and improvement of non-uniform distance from electrodes to skin.U-shape applicator can be expected to play an important role in clinical hyperthermic oncology.