Monte-Carlo simulation of a slot-scanning digital mammography system for tomosynthesis.

BACKGROUND: Digital breast tomosynthesis (DBT) reconstructs planar slices of the breast based on two-dimensional angular projections. Early studies and clinical trials show that DBT is an improvement over full field digital mammography (FFDM) because it provides the radiologist with better image quality and more information.

OBJECTIVE: This paper presents a simulation system to model the performance of a slot-scanning FFDM and DBT system.

METHODS: A tissue-equivalent three dimensional (3D) breast phantom was constructed, validated for slot-scanning digital mammography and used in simulating digital breast tomosynthesis. The simulation system was validated by comparing images acquired with a slot-scanning mammography machine with simulated phantom images, using the edge-test method and image quality metrics modulation transfer function (MTF), noise power spectrum (NPS) and detective quantum efficiency (DQE). Different two-dimensional (2D) projections of the 3D phantom were simulated and the phantom was reconstructed using filtered backprojection.

RESULTS: Image quality metrics showed equivalence between simulated and real images.

CONCLUSIONS: The simulation tool is suitable for slot-scanning FFDM and DBT and may be used for the design and comparison of mammography systems.