Design of a compact antenna with flared groundplane for a wearable breast hyperthermia system. (3rd October 2015)

• Record Type: Journal Article
• Authors: Curto, Sergio; Prakash, Punit
• Is Part Of: International journal of hyperthermia. Volume 31:Number 7(2015)
• Page Start: 726
• Page End: 736
• Publication Date: 2015-10-03
• Subjects: Breast cancer treatment -- flared groundplane -- microwave hyperthermia -- patch antenna -- wearable medical devices; Thermotherapy -- Periodicals; 615.832
• DOI: 10.3109/02656736.2015.1063170
• Languages: English
• ISSNs: 0265-6736

Abstract

Abstract: Purpose : Currently available microwave hyperthermia systems for breast cancer treatment do not conform to the intact breast and provide limited control of heating patterns, thereby hindering an effective treatment. A compact patch antenna with a flared groundplane that may be integrated within a wearable hyperthermia system for the treatment of the intact breast disease is proposed. Materials and methods : A 3D simulation-based approach was employed to optimise the antenna design with the objective of maximising the hyperthermia treatment volume (41 °C iso-therm) while maintaining good impedance matching. The optimised antenna design was fabricated and experimentally evaluated with ex vivo tissue measurements. Results : The optimised compact antenna yielded a −10 dB bandwidth of 90 MHz centred at 915 MHz, and was capable of creating hyperthermia treatment volumes up to 14.4 cm 3 (31 mm × 28 mm × 32 mm) with an input power of 15 W. Experimentally measured reflection coefficient and transient temperature profiles were in good agreement with simulated profiles. Variations of + 50% in blood perfusion yielded variations in the treatment volume up to 11.5%. When compared to an antenna with a similar patch element employing a conventional rectangular groundplane, the antenna with flared groundplane afforded 22.3% reduction in required power levels to reach the same temperature, and yielded 2.4 times larger treatment volumes. Conclusion : The proposed patch antenna with a flared groundplane may be integrated within a wearable applicator for hyperthermia treatment of intact breast targets and has the potential to improve efficiency, increase patient comfort, and ultimately clinical outcomes.