Ohguri Takayuki, Kuroda Kagayaki, Yahara Katsuya, Nakahara Sota, Kakinouchi Sho, Itamura Hirohide, Morisaki Takahiro, Korogi Yukunori
Department of Therapeutic Radiology, University Hospital of Occupational and Environmental Health, Kitakyushu 807-8555, Japan.
School of Information Science and Technology, Tokai University, Hiratsuka 259-1292, Japan.
Cancers (Basel). 2021 Feb 26;13(5):979. doi: 10.3390/cancers13050979.
The purpose of this study was to evaluate the effectiveness of the clinical setting for deep regional hyperthermia of an 8 MHz radiofrequency (RF) capacitively coupled device in the pelvis by using numerical simulations of the electromagnetic field. A three-dimensional patient model of cervical cancer of the uterus in an obese patient was reconstructed with computed tomography data. The specific absorption rate (SAR) and temperature distributions among the various heating settings were evaluated using numerical simulations. The averaged SAR value of the deep target tumor was similar between with or without overlay boluses (OBs), and that of the subcutaneous fat (SF) at the edges of cooling boluses with OBs was lower than that of the SF without OBs. The use of OBs reduced the overheating of the SF. The 0.5% salt solution in the OB produced the least overheated areas outside the deep target tumor compared with the other concentrations. The insertion of the intergluteal cleft (IGC) bolus could improve the temperature concentration of the deep target tumor. The use of OBs and the salt solution concentration in the OB were important to optimize the temperature distribution. IGC bolus might contribute to temperature optimization. Further studies with individualized numerical simulations in each patient are expected.
本研究的目的是通过电磁场数值模拟，评估8MHz射频（RF）电容耦合装置在骨盆中进行深部区域热疗的临床环境有效性。利用计算机断层扫描数据重建了肥胖患者子宫颈癌的三维患者模型。使用数值模拟评估了各种加热设置下的比吸收率（SAR）和温度分布。有或没有覆盖推注（OBs）时，深部目标肿瘤的平均SAR值相似，有OBs时冷却推注边缘皮下脂肪（SF）的平均SAR值低于没有OBs时的SF。使用OBs可减少SF的过热。与其他浓度相比，OB中0.5%的盐溶液在深部目标肿瘤外产生的过热区域最少。臀间裂（IGC）推注的插入可提高深部目标肿瘤的温度集中度。使用OBs和OB中的盐溶液浓度对于优化温度分布很重要。IGC推注可能有助于温度优化。预计将对每位患者进行个体化数值模拟的进一步研究。
