A multilayered skin-fat-muscle phantom embedded with thermocouples for non-ablative RF heating: numerical simulation...

Area of Science:

• Biomedical Engineering
• Medical Physics
• Dermatology

Background:

• Non-ablative radiofrequency (RF) skin rejuvenation utilizes controlled volumetric heating of skin and subcutaneous tissues.
• Clinical validation of RF devices is costly and ethically challenging.
• Existing single-layer phantoms lack the electrothermal heterogeneity needed for accurate simulation validation.

Purpose of the Study:

• Develop a thermocouple-embedded, multilayered phantom (MLP) mimicking skin, fat, and muscle.
• Simulate electrothermal behavior for RF skin rejuvenation.
• Enable depth-resolved temperature measurement for benchtop evaluation and model validation.

Main Methods:

• Fabricated a three-layer MLP (skin, fat, muscle) with embedded thermocouples at -1, -3, and -4 mm.
• Measured MLP electrical and thermal properties, comparing them to human tissue ranges.
• Developed a 3D coupled electrothermal simulation and compared its results to experimental temperature measurements.

Main Results:

• MLP properties were consistent with reported human tissue values.
• Simulated and experimental temperature profiles showed strong agreement (temperature differences <4%).
• The MLP demonstrated superior accuracy in simulating layer-dependent temperature evolution compared to a single-layer skin phantom (SLSP).

Conclusions:

• The MLP offers a reproducible platform for depth-resolved temperature characterization of RF heating.
• It facilitates experimental validation of electrothermal simulations for RF skin rejuvenation.
• The MLP supports efficient screening and benchmarking of RF device settings and electrode designs.