A polyacrylamide gel phantom for radiofrequency ablation

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Materials Science

Background:

• Radiofrequency ablation (RFA) is a widely used medical procedure.
• Accurate visualization of thermal coagulation during RFA is crucial for effective treatment and patient safety.
• Current methods for visualizing RFA-induced thermal changes in tissue have limitations.

Purpose of the Study:

• To introduce a new tissue-mimicking phantom for visualizing 3D coagulation temperature distribution during RFA.
• To develop a phantom with physical and thermal properties similar to biological tissues.
• To demonstrate the phantom's utility in RFA investigations.

Main Methods:

• A polyacrylamide gel (PAG) phantom incorporating bovine serum albumin (BSA) was developed.
• The phantom's coagulation temperature was adjusted between 50-60°C by modifying the pH (4.3-4.7).
• Physical properties (density, electrical conductivity, specific heat capacity) were optimized to match soft tissues.
• Magnetic resonance (MR) properties were assessed for their change upon thermal coagulation.

Main Results:

• The PAG-BSA phantom is transparent, with coagulated regions appearing ivory white, enabling clear visualization of RFA lesions.
• The phantom exhibits favorable physical properties comparable to soft biological tissues.
• Significant changes in MR properties upon thermal coagulation were observed.
• The phantom successfully visualized RFA-induced lesions.

Conclusions:

• The developed PAG-BSA phantom is a valuable tool for visualizing thermal coagulation during RFA.
• Its tunable properties and MR characteristics make it suitable for RFA device characterization, quality assurance, and treatment planning/verification.
• This phantom offers an attractive alternative for RFA research and development.