MCNPX internal dosimetry studies based on the NORMAN-05 voxel model

Area of Science:

• Medical Physics
• Radiation Dosimetry
• Computational Modeling

Background:

• Anthropomorphic computational models are essential for radiation protection dosimetry, particularly for estimating absorbed energy from incorporated radionuclides.
• While MIRD-based analytical models are standard, voxel phantoms offer a more accurate representation using real anatomical data.

Purpose of the Study:

• To evaluate the effectiveness of the NORMAN-05 voxel phantom and MCNPX Monte Carlo code for radiation dosimetry.
• To assess absorbed fractions for gamma emitters and organ doses for 90Sr incorporation.

Main Methods:

• Utilized the NORMAN-05 voxel phantom, a modified version of the NORMAN model.
• Employed the MCNPX Monte Carlo code for radiation transport simulations.
• Conducted preliminary investigations on absorbed fractions and organ absorbed doses.

Main Results:

• Preliminary results demonstrate the capability of voxel phantoms in evaluating absorbed fractions for various source-target organ pairs with gamma emitters.
• Organ absorbed doses were estimated for 90Sr incorporation using the NORMAN-05 model.

Conclusions:

• Voxel phantoms like NORMAN-05 represent a valid and potentially superior alternative to traditional models for radiation protection and dosimetry.
• These models enhance dose evaluation accuracy, especially for patient-specific assessments in nuclear medicine and radiotherapy, and for workplace accidental internal contamination.