Comparison of Microwave Hyperthermia Applicator Designs with Fora Dipole and Connected Array

Area of Science:

• Biomedical Engineering
• Electromagnetics
• Medical Physics

Background:

• Microwave hyperthermia therapy utilizes electromagnetic waves to heat tumors, requiring effective applicator designs for optimal treatment.
• The design of microwave hyperthermia applicators is crucial for therapeutic efficacy and real-time application feasibility.

Purpose of the Study:

• Investigate fractal octagonal ring antenna elements for breast tumor hyperthermia at 2.45 GHz.
• Evaluate dipole and connected array configurations for selective tumor heating and minimizing hotspots.

Main Methods:

• Simulated breast phantom models with various fractal octagonal ring antenna array designs using COMSOL Multiphysics.
• Optimized antenna excitation phases and magnitudes via a global particle swarm algorithm.
• Analyzed specific absorption rate (SAR) distributions for different applicator designs.

Main Results:

• 16-antenna dipole arrays (circular, linear, cross) showed superior performance in 1-layer designs.
• Two-layer dipole arrays outperformed one-layer arrays for deep-tissue targets.
• Connected arrays with more layers excelled in superficial regions compared to dipole arrays.

Conclusions:

• Fractal octagonal ring antenna arrays are effective for microwave hyperthermia.
• Optimized multi-layer dipole and connected arrays offer improved tumor targeting.
• A 1-layer 12-antenna circular fractal octagonal ring antenna array (FORA) dipole array is feasible for clinical application.