Computational absorption and reflection studies of normal human skin at 0.45 THz

Area of Science:

• Biophysics
• Medical Physics
• Electromagnetics

Background:

• Terahertz (THz) frequency radiation applications are expanding, leading to increased potential for human exposure.
• Understanding THz radiation interaction with biological tissues is crucial for safety assessments and novel diagnostic applications.

Purpose of the Study:

• To simulate and analyze the specific absorption rate (SAR) and temperature distribution in thin skin exposed to 0.45 THz radiation.
• To investigate the potential of reflection studies using polarized THz radiation for assessing diabetic neuropathy.

Main Methods:

• Power density and SAR simulations were performed on thin skin models at 0.45 THz.
• Analysis focused on energy absorption depth and maximal temperature rise within skin layers.
• Reflection studies explored the use of acute angles and polarized radiation.

Main Results:

• The bulk of 0.45 THz radiation energy is absorbed in the upper stratum spinosum of thin skin.
• Maximal temperature increases were observed in the lower stratum spinosum.
• Significant localized SAR increases (up to 100% above average) occurred at the stratum spinosum/stratum basale boundary.

Conclusions:

• The stratum corneum provides a protective barrier in thick skin, but deeper layers are susceptible to THz absorption.
• Specific absorption patterns highlight potential localized heating effects in the epidermis.
• Polarized THz radiation and acute angle reflections show promise for non-invasive diabetic neuropathy assessment.