Off-center spherical model for dosimetry calculations in chick brain tissue

Area of Science:

• Electromagnetics
• Bioengineering
• Computational Biology

Background:

• Realistic modeling of biological tissues is crucial for understanding electromagnetic field interactions.
• Existing concentric spherical models have limitations in simulating complex tissue geometries.
• Accurate simulation of electric fields and power absorption is essential for safety assessments.

Purpose of the Study:

• To develop and validate an off-center spherical model for calculating electric field and absorbed power density in chick brain tissue.
• To analyze the impact of surrounding buffer solution on field distribution.
• To compare the off-center model's predictions with traditional models.

Main Methods:

• Utilized an off-center spherical model to represent chick brain tissue in a test tube.
• Employed a series of zonal harmonics for field distribution calculations.
• Developed a novel method for expanding spherical harmonics about an off-center origin.
• Performed numerical simulations at a carrier frequency of 147 MHz.

Main Results:

• The off-center model provides a more realistic simulation compared to concentric models.
• Absorbed power density increases towards the bottom surface of the brain tissue.
• Developed scaling relations for electric field intensity inside and outside the brain.
• Off-center model scaling ratios fall between concentric and isolated spherical model predictions.

Conclusions:

• The off-center spherical model enhances the accuracy of electromagnetic simulations in biological tissues.
• This model offers improved insights into radiofrequency energy deposition in brain tissue.
• The findings contribute to more precise safety evaluations for electromagnetic exposure studies.