Improving locoregional hyperthermia delivery using the 3-D controlled AMC-8 phased array hyperthermia system: a...

Area of Science:

• Biomedical Engineering
• Medical Physics
• Oncology

Background:

• Preclinical evaluation of the novel AMC-8 regional hyperthermia system.
• The AMC-8 system features a two-ring phased array with four 70 MHz waveguides for 3-D Specific Absorption Rate (SAR) control.
• Designed to enhance tumor temperatures and improve locoregional hyperthermia efficacy.

Purpose of the Study:

• To conduct a preclinical evaluation of the AMC-8 regional hyperthermia system.
• To assess the 3-D SAR control capabilities of the AMC-8 system.
• To compare the AMC-8 system's performance against its predecessor, the 2-D AMC-4 system.

Main Methods:

• Simulations and measurements were performed using homogeneous tissue-equivalent phantoms (rectangular and elliptical).
• Evaluated spatial control, SAR focus size, and the ratio of maximum SAR outside the target region to SAR in the focus.
• Varied the distance and phase difference between the two rings of the AMC-8 array.

Main Results:

• The AMC-8 system demonstrated 3-D SAR control via phase steering.
• Achieved a more elongated SAR focus compared to the AMC-4 system.
• Exhibited reduced superficial SAR deposition (half that of AMC-4), leading to a more favorable normal tissue to target SAR ratio and enabling higher power deposition.

Conclusions:

• The AMC-8 system provides effective 3-D SAR control with a superior SAR distribution compared to the 2-D AMC-4 system.
• These findings suggest potential for improved clinical tumor temperatures.
• The enhanced SAR control and distribution indicate a promising advancement in hyperthermia treatment.