Predrag Bakic
Associate Professor
Estimation of scattered radiation in digital breast tomosynthesis
Author
Summary, in English
Digital breast tomosynthesis (DBT) is a promising technique to overcome the tissue superposition limitations found in planar 2D x-ray mammography. However, as most DBT systems do not employ an anti-scatter grid, the levels of scattered radiation recorded within the image receptor are significantly higher than that observed in planar 2D x-ray mammography. Knowledge of this field is necessary as part of any correction scheme and for computer modelling and optimisation of this examination. Monte Carlo (MC) simulations are often used for this purpose, however they are computationally expensive and a more rapid method of calculation is desirable. This issue is addressed in this work by the development of a fast kernel-based methodology for scatter field estimation using a detailed realistic DBT geometry. Thickness-dependent scatter kernels, which were validated against the literature with a maximum discrepancy of 4% for an idealised geometry, have been calculated and a new physical parameter (air gap distance) was used to estimate more accurately the distribution of scattered radiation for a series of anthropomorphic breast phantom models. The proposed methodology considers, for the first time, the effects of scattered radiation from the compression paddle and breast support plate, which can represent more than 30% of the total scattered radiation recorded within the image receptor. The results show that the scatter field estimator can calculate scattered radiation images in an average of 80 min for projection angles up to 25° with equal to or less than a 10% error across most of the breast area when compared with direct MC simulations.
Publishing year
2014-08-07
Language
English
Pages
4375-4390
Publication/Series
Physics in Medicine and Biology
Volume
59
Issue
15
Document type
Journal article
Publisher
IOP Publishing
Topic
- Medical Image Processing
- Cancer and Oncology
Keywords
- convolution
- digital breast tomosynthesis
- Monte Carlo simulations
- scatter kernel
- scatter-to-primary ratio
- scattered radiation
Status
Published
ISBN/ISSN/Other
- ISSN: 0031-9155