Preliminary results of 3D dose calculations with MCNP-4B code from a SPECT image

Area of Science:

• Medical Physics
• Computational Imaging
• Radiation Dosimetry

Background:

• Accurate 3D dose calculation is crucial for radiation therapy planning.
• Existing methods for processing medical imaging data for dose calculations can be complex.
• Monte Carlo simulations offer high accuracy but require specific input formats.

Purpose of the Study:

• To develop interface software for generating MCNP-4B input files from medical images in Interfile format.
• To validate the software's performance using a known phantom.
• To compare the accuracy of Monte Carlo MCNP-4B dose calculations with the voxel S factor method.

Main Methods:

• Developed interface software to convert Interfile medical images (version 3.3) into MCNP-4B input files.
• Utilized a spherical phantom with known activity distribution (generated via IMAGAMMA) for testing.
• Performed 3D dose calculations using the Monte Carlo MCNP-4B code.
• Compared results against the established voxel S factor method.

Main Results:

• The developed software successfully generated input files for Monte Carlo simulations from medical images.
• 3D dose calculations using MCNP-4B showed excellent agreement with the voxel S factor method.
• A relative error of less than 1% was observed between the two calculation methods.

Conclusions:

• The developed interface software is effective for preparing medical imaging data for Monte Carlo-based dose calculations.
• Monte Carlo MCNP-4B simulations, facilitated by the new software, provide highly accurate 3D dose distributions.
• This approach offers a reliable and precise tool for radiation dosimetry applications.