Optimization of low-cost needle microwave applicators for cancer therapy

In this paper, the design and optimization of a low-cost needle microwave applicator for cancer therapy is illustrated. An adequately sized coaxial antenna inserted into a thin hypodermic needle, is optimized in the Industrial, Scientific and Medical frequency band (ISM) at f = 2.45 GHz. An extensive feasibility investigation is performed in order to obtain an efficient, mini-invasive and low-cost microwave medical device. Several technical solutions are explored and the optimization of a number of needle microwave applicators is performed. The performance of the applicators is evaluated in terms of antenna impedance matching, specific absorption rate (SAR), temperature distribution, and ablation zone sizes. After a comparison, a 14 gauge (14G) and a 16 gauge (16G) prototypes are fabricated and characterized.