Chan K W, Chou C K, McDougall J A, Luk K H
Department of Radiation Research, City of Hope, National Medical Center, Duarte, California 91010-0269.
Int J Hyperthermia. 1988 Jul-Aug;4(4):447-56. doi: 10.3109/02656738809016497.
The changes in heating patterns due to perturbations by thermometer probes in microwave fields were investigated in static phantoms at 915 and 434 MHz. Thermograms taken parallel to the plane of E and H fields, at depths of up to 2 cm, indicated heating changes of +25 to -45 per cent at 915 MHz and +/- 15 per cent at 434 MHz. The amount of perturbation is dependent on the length, size and location of the probes in the RF fields and their orientations to the electric field. If proper probe placement techniques are not observed when metallic probes are involved, hot and cool spots can be generated and shifted to sites that are not measured. Therefore misleading temperatures can result when changes in heating patterns are not detected. Perturbation also varies with applicator designs and phantom geometry. If thermistors and thermocouples are used, the effects of perturbation should be investigated with individual applicators under applicable clinical conditions.
在915兆赫和434兆赫的静态仿真人体模型中，研究了温度计探头在微波场中引起的加热模式变化。在与电场和磁场平面平行的方向上，在深度达2厘米处拍摄的温度记录图表明，在915兆赫时加热变化为+25%至-45%，在434兆赫时为+/-15%。扰动的大小取决于探头在射频场中的长度、尺寸和位置以及它们相对于电场的方向。当使用金属探头时，如果未遵循正确的探头放置技术，可能会产生热点和冷点，并转移到未测量的部位。因此，当未检测到加热模式的变化时，可能会导致误导性的温度。扰动也会因施源器设计和仿真人体模型的几何形状而有所不同。如果使用热敏电阻和热电偶，应在适用的临床条件下，针对单个施源器研究扰动的影响。
