Malhotra Neeru, Marwaha Anupma, Kumar Ajay
a DAV Institute of Engineering and Technology, ECE , Jalandhar , Punjab , India.
b Sant Longowal Institute of Engineering and Technology, ECE, Longowal , Sangrur , Punjab , India.
Electromagn Biol Med. 2016;35(3):214-21. doi: 10.3109/15368378.2015.1048550. Epub 2015 Jul 6.
Microwave ablation is rapidly being rediscovered and developed for treating many cancers of liver, lung, kidney and bone, as well as arrhythmias and other medical conditions. The microwaves ablate tissue by heating it to cytotoxic temperatures. The microwave antenna design suffers the challenges of effective coupling and penetration into body tissues, uncontrolled power deposition due to applicator construction limitations affecting uniform heating of target region, and narrowband operation leading to mismatch for many patients and detrimental heating. To meet out the requirements of wideband operation and localized lesion reconfigurable linearly tapered slot interstitial wideband antenna has been proposed for working in the 1.38 GHz to 4.31 GHz frequency band. The performance of the antenna is evaluated by using FEM-based HFSS software. The slot height and taper height are reconfigured for parametric analysis achieving maximum impedance matching and spherical ablation zone without requiring any additional adjustable structures. The tapering of the slot in coaxial antenna generates current distribution at the edges of the slot for maximizing specific absorption rate.
微波消融正迅速被重新发现并应用于治疗多种肝脏、肺部、肾脏和骨骼癌症以及心律失常和其他病症。微波通过将组织加热到细胞毒性温度来消融组织。微波天线设计面临有效耦合和穿透人体组织的挑战、由于施加器结构限制导致的功率沉积不受控制从而影响目标区域的均匀加热,以及窄带操作导致许多患者出现失配和有害加热的问题。为了满足宽带操作的要求以及实现局部病灶的可重构性,已提出线性渐变缝隙型宽带天线在1.38 GHz至4.31 GHz频段工作。通过基于有限元法的HFSS软件评估天线性能。对缝隙高度和渐变高度进行重新配置以进行参数分析,从而在无需任何额外可调结构的情况下实现最大阻抗匹配和球形消融区。同轴天线中缝隙的渐变在缝隙边缘产生电流分布,以最大化比吸收率。