Montecchia F
Department of Electronics and Automatics, University of Ancona, Italy.
IEEE Trans Biomed Eng. 1992 Jun;39(6):580-8. doi: 10.1109/10.141196.
Microstrip antennas have many different advantages over other RF/MW radiative applicators employed for superficial hyperthermia treatment. This is mainly due to their compact and body-conformable structure as well as to printed circuit board techniques, both of which allow a wide design flexibility for superficial tumor heating. Among the wide variety of radiator configurations, three microstrip antennas of increasing complexity with electromagnetic and heating characteristics potentially suitable as applicators for superficial hyperthermia have been designed, developed, and tested in different radiative conditions: a microstrip disk, a microstrip annular-slot, and a microstrip spiral. Electromagnetic design criteria are presented together with the determinations of the applicator return loss versus frequency and thermograms of the near-field heating pattern in muscle-like phantom. The results are in good agreement with theory and indicate that: i) the operating frequency is either single or multiple according to the applicator-mode, "resonant" or "traveling-wave," and can be chosen in the useful frequency range for hyperthermia (200-1000 MHz) according to the tumor cross-section and depth; ii) the heating pattern flexibility increases going from the simple geometry disk to the annular-slot and spiral applicators; iii) a distilled-water bolus is required; iv) the annular-slot applicator exhibits the highest efficiency, while the spiral applicator provides the best performance.
与用于浅表热疗的其他射频/微波辐射器相比，微带天线具有许多不同的优点。这主要归功于其紧凑且贴合身体的结构以及印刷电路板技术，这两者都为浅表肿瘤加热提供了广泛的设计灵活性。在各种各样的辐射器配置中，已经设计、开发并在不同辐射条件下测试了三种电磁和加热特性日益复杂、有可能用作浅表热疗辐射器的微带天线：一个微带圆盘、一个微带环形缝隙天线和一个微带螺旋天线。文中给出了电磁设计标准，以及辐射器回波损耗随频率的变化情况和在肌肉模拟体模中近场加热模式的热成像图。结果与理论吻合良好，表明：i）根据辐射器模式“谐振”或“行波”，工作频率为单频或多频，并且可根据肿瘤横截面和深度在热疗的有用频率范围（200 - 1000兆赫兹）内选择；ii）从简单几何形状的圆盘到环形缝隙天线和螺旋天线辐射器，加热模式灵活性增加；iii）需要蒸馏水填充；iv）环形缝隙天线辐射器效率最高，而螺旋天线辐射器性能最佳。
