Normalized mean glandular dose computation from mammography using GATE: a validation study.

Area of Science:

• Medical Physics
• Radiation Dosimetry
• Computational Imaging

Background:

• Mean glandular dose (MGD) is crucial for assessing patient breast dose in mammography.
• Current Monte Carlo methods require normalized MGD derived from incident air kerma.
• The Geant4 Application for Tomographic Emission (GATE) toolkit lacks functionality for normalized MGD calculation.

Purpose of the Study:

• To extend the GATE toolkit with new modules for calculating normalized MGD in mammography.
• To validate the developed modules against published data and assess their accuracy.
• To investigate the impact of skin thickness and composition on normalized MGD.

Main Methods:

• Development of two new modules within the GATE toolkit.
• Utilized Monte Carlo simulations for normalized MGD computation in compressed breast phantoms.
• Validated results against published data across various half-value layers (HVLs).
• Investigated variations in normalized MGD by altering skin tissue properties.

Main Results:

• The extended GATE toolkit successfully provided normalized MGD values.
• Validated results showed good agreement with existing literature.
• Significant changes in normalized MGD were observed with variations in skin thickness and composition, particularly for breast thicknesses other than 5 cm.

Conclusions:

• The new GATE modules provide a reliable method for calculating normalized MGD.
• The findings highlight the importance of considering skin properties in breast dose estimation.
• Potential need for revising standard breast phantom models based on skin composition effects.