Premium
Influence of scatter reduction method and monochromatic beams on image quality and dose in mammography
Author(s) -
Moeckli Raphaël,
Verdun Francis R.,
Fiedler Stefan,
Pachoud Marc,
Bulling Shelley,
Schnyder Pierre,
Valley JeanFrançois
Publication year - 2003
Publication title -
medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.473
H-Index - 180
eISSN - 2473-4209
pISSN - 0094-2405
DOI - 10.1118/1.1626988
Subject(s) - collimated light , monochromatic color , optics , mammography , image quality , dosimetry , synchrotron radiation , physics , radiation , beam (structure) , detector , laser beam quality , reduction (mathematics) , materials science , nuclear medicine , computer science , mathematics , image (mathematics) , medicine , laser , geometry , cancer , artificial intelligence , breast cancer , laser beams
In mammography, the image contrast and dose delivered to the patient are determined by the x‐ray spectrum and the scatter to primary ratio S / P . Thus the quality of the mammographic procedure is highly dependent on the choice of anode and filter material and on the method used to reduce the amount of scattered radiation reaching the detector. Synchrotron radiation is a useful tool to study the effect of beam energy on the optimization of the mammographic process because it delivers a high flux of monochromatic photons. Moreover, because the beam is naturally flat collimated in one direction, a slot can be used instead of a grid for scatter reduction. We have measured the ratio S / P and the transmission factors for grids and slots for monoenergetic synchrotron radiation. In this way the effect of beam energy and scatter rejection method were separated, and their respective importance for image quality and dose analyzed. Our results show that conventional mammographic spectra are not far from optimum and that the use of a slot instead of a grid has an important effect on the optimization of the mammographic process. We propose a simple numerical model to quantify this effect.