Performance evaluation of SAR and temperature analysis for local hyperthermia of breast tumor using tooth shaped rectangular antenna with a slit

The article presents a cost-effective, compact, lightweight tooth shaped rectangular antenna (TSRA), a microstrip antenna for hyperthermia treatment of breast tumor. Hyperthermia treatment methodology for the treatment of breast tumor is investigated in this article. A coupled Simulation of TSRA and four layer breast model is carried out in CST-MW suite v.17. The TSRA is integrated with a 4-layer breast model. Investigations of the SAR temperature variations in hyperthermia treatment of breast tumor and healthy breast tissue are carried out for the different sizes of tumors, 10, 15, 20, 25, and 30 mm3. Hyperthermia treatment has side effect of overheating of surrounding healthy tissues, which develops hotspots on healthy tissues. To reduce the side effects of hyperthermia, we have integrated a water bolus with breast model to match the medium properties and give cooling effect. A water bolus is used as a matching medium between TSRA and the outer layer (skin) of the breast model. Temperature variations and SAR deposited in tumor, and healthy tissue is observed. It clearly shows that all healthy tissues have less effect if integrated with water bolus. However, it also reduces SAR and corresponding temperature for the same input power. The designed compact (36 × 24 mm) rectangular microstrip antenna offers a bandwidth of 1.2 GHz and at a resonant frequency of 2.76 GHz. The investigations for HT of both breast models confirm that water bolus improves impact of HT and reduces hotspots. Simulated SAR values acquired for 1-g and 10-g tissue mass are acceptable and proportionate with the IEEE C95.1 standard. The applicator could be the most suitable candidate for microwave HT of breast tumor.