Estimation of glandular dose distribution in mammography using EGS5

The aim of this research is to analyze the absorbed dose distribution by changes of thickness of subcutaneous adipose and target-filter combination in mammography using EGS5. Assume the mammography examination, x-ray tube voltage, compression plate, breast model phantom, and image receptor were included in EGS5 code. That breast model phantom had various thicknesses of subcutaneous adipose. Our results showed that absorbed dose was a tendency to increase with thinning of the subcutaneous adipose thickness. It indicated that average glandular dose (AGD) that is recently used could have been underestimated. Also relative absorbed dose of glandular tissues tended to be low when the energy of incident x-ray became large. It indicated that target/filter combinations have strong effect to incident x-ray supectrum, so that we must choose most proper target/filter combinations that reduce the radiation dose while maintaining image contrast.