Time-multiplexed beamforming for noninvasive microwave hyperthermia treatment

Area of Science:

• Biomedical Engineering
• Medical Physics
• Electromagnetics

Background:

• Noninvasive localized hyperthermia is crucial for cancer treatment.
• Conventional microwave beamforming can lead to unintended heating of healthy tissues.
• Optimizing microwave energy delivery for targeted thermal therapies remains a challenge.

Purpose of the Study:

• To propose and evaluate a novel time-multiplexed microwave beamforming strategy for selective localized heating of biological tissues.
• To assess the effectiveness of this technique for brain hyperthermia treatment using a high-fidelity head phantom.
• To compare the performance of time-multiplexed beamforming against conventional methods.

Main Methods:

• Development of a time-multiplexing strategy for multiple microwave beamformers.
• Utilizing a high-fidelity numerical head phantom (Virtual Family) for realistic simulations.
• Employing finite-difference time-domain (FDTD) method for electromagnetic and thermal simulations.
• Designing patient-specific propagation models based on detailed head geometry and tissue dielectric properties at 1 GHz.

Main Results:

• The time-multiplexed beamforming technique effectively reduced unintended heating of healthy brain tissue.
• Treatment temperature and volume were maintained without adverse effects.
• The method demonstrated efficacy for target locations in three distinct brain regions.
• Simulations confirmed improved hyperthermia performance compared to conventional beamforming.

Conclusions:

• Time-multiplexed microwave beamforming provides a noninvasive and selective method for localized tissue heating.
• This approach enhances the safety and precision of microwave-induced hyperthermia for brain cancer treatment.
• The technique holds potential for improving localized heating in cancer therapy and heat-activated drug delivery.