Related Experiment Video
Updated: Jun 2, 2026
06:20
Irradiator Commissioning and Dosimetry for Assessment of LQ α and β Parameters, Radiation Dosing Schema, and in vivo Dose Deposition
Published on: March 11, 2021
Assessment of MIRD data for internal dosimetry using the GATE Monte Carlo code.
Ali Asghar Parach1, Hossein Rajabi, Mohammad Ali Askari
1Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, P.O. Box 14115-331, Tehran, Iran.
Radiation and Environmental Biophysics
|May 17, 2011
Summary
This study compared dose calculations from GATE/GEANT Monte Carlo code with MIRD data using the Snyder phantom. Results show good agreement for higher photon energies, but discrepancies at lower energies highlight the need for careful validation.
Area of Science:
- Medical Physics
- Nuclear Medicine
- Computational Dosimetry
Background:
- GATE/GEANT is a Monte Carlo code for nuclear medicine dose calculations.
- MIRD is a well-established system for human organ dose estimation.
- Validation of computational tools is crucial in nuclear medicine.
Purpose of the Study:
- To compare organ dose calculations between GATE/GEANT and MIRD using the Snyder phantom.
- To assess the agreement of Specific Absorbed Fraction (SAF) data across various photon energies.
- To identify discrepancies and their dependence on photon energy and SAF values.
Main Methods:
- Discretized the mathematical Snyder phantom into a 100 × 200 × 360 voxel digital phantom.
- Simulated dose calculations using GATE/GEANT with mono-energetic photons (10-1000 keV).
- Compared GATE/GEANT-derived SAF values with published MIRD data.
Main Results:
- Good overall correlation (r² > 0.99) between GATE/GEANT and MIRD data.
- GATE/GEANT showed slightly lower self-absorption (-0.16 ± 6.22%) than MIRD.
- Significant differences in lung self-absorption at low photon energies (10-20 keV).
- Higher GATE/GEANT cross-irradiation doses (+1.5 ± 8.1%) than MIRD for 50-1000 keV photons.
- Poor agreement at low photon energies (10-30 keV) due to small SAF values and cross-section effects.
- Acceptable agreement with negligible bias for higher photon energies (50-1000 keV).
Conclusions:
- GATE/GEANT and MIRD data show good agreement for higher photon energies (50-1000 keV).
- Discrepancies at lower photon energies (10-30 keV) are influenced by SAF magnitude and photon energy.
- Further investigation is needed for low-energy photon dosimetry validation in Monte Carlo codes.
