Solving the Time- and Frequency-Multiplexed Problem of Constrained Radiofrequency Induced Hyperthermia

Area of Science:

• Biomedical Engineering
• Medical Physics
• Computational Electromagnetics

Background:

• Targeted radiofrequency (RF) heating for hyperthermia has applications in cancer treatment and drug delivery.
• Current methods for focal RF heating are often time-consuming due to nonconvex optimization or approximations.
• This limits the practical application of RF hyperthermia.

Purpose of the Study:

• To develop a fast and globally optimal algorithm for focal RF heating.
• To enable precise control over RF power deposition patterns and frequencies.
• To facilitate interactive hyperthermia treatment planning.

Main Methods:

• The problem of focal RF heating is reformulated as a semidefinite program.
• A novel algorithm quickly solves this program to global optimality.
• The approach supports voxel-level definition of target regions, power deposition patterns, and constraints.

Main Results:

• The algorithm efficiently solves large-scale (human voxel) models.
• Demonstrated applicability in 2D and 3D examples, including human brain models with tumors.
• Achieves solutions for typical clinical problems in seconds, enabling real-time planning.

Conclusions:

• The proposed semidefinite programming approach offers a significant advancement for RF hyperthermia.
• It enables rapid, globally optimal treatment planning, crucial for clinical applications.
• The algorithm is well-suited for interactive planning, safety management, and applicator design.