Parameter variation effects on millimeter wave dosimetry based on precise skin thickness in real rats

Area of Science:

• Biophysics
• Thermal Modeling
• Electromagnetic Bioeffects

Background:

• Understanding thermal effects of millimeter waves (6-100 GHz) on biological tissues is crucial for safety assessments.
• Accurate modeling requires precise anatomical data of skin layers.

Purpose of the Study:

• To perform a parametric analysis of steady-state temperature elevation in rat skin exposed to millimeter waves (6-100 GHz).
• To investigate the influence of rat skin structure and thermal properties on temperature rise.
• To compare temperature elevation in rat skin models with human skin models.

Main Methods:

• Histological analysis of excised Sprague-Dawley rat skin to determine layer thicknesses (epidermis, dermis, dermal white adipose tissue, panniculus carnosus).
• Solving the bioheat transfer equation using precise rat skin structural data.
• Parametric analysis considering variations in body parts and thermal constants.

Main Results:

• The dermal white adipose tissue layer in rats is notably thin.
• Rat skin surface temperature elevation is significantly lower (52.6-32.3% in head, 83.3-58.8% in dorsal skin) compared to human skin models across 6-100 GHz.
• Surface temperature elevation correlates with tissue thickness and deep blood perfusion rates.

Conclusions:

• Rat skin exhibits lower temperature elevation under millimeter wave exposure compared to human models due to anatomical differences.
• Tissue thickness and blood perfusion are key factors influencing thermal responses in biological tissues.
• Provides essential data for accurate thermal safety assessments of millimeter wave applications in rats.