Calculation and analysis of DQE for some image detectors in mammography
1998 (English)Report (Other academic)
The development and clinical testing of digital detector designs for mammography are making rapid progress and there is widespread interest in comparing the performance of these new detectors to that of analogue screen-film mammography systems. In this report, Monte Carlo calculations of the x-ray absorption characteristics (single-event distribution), the quantum absorption, Aq, and detective quantum, DQEq, efficiencies are made and compared to results from the literature. Detectors of CsI and Si of various thicknesses are compared to a state-ofthe art analogue, screen-film system (Gd2O2S) in the energy range 1-35 keV. The results show that 1.5 mm thick Si detectors will have the same DQEq as commonly used Gd2O2S fluorescent screens and that a CsI phosphor of 80 mm has similar DQEq as 1.0 mm Si. The total DQE (including added noise and inherent detector unsharpness) of fluorescent screen-film systems will be significantly reduced from this value due to the light scatter, film noise and the inherent limitations caused by the film characteristic curve. This indicates that also thinner Si detectors (0.3-0.5 mm), which do not suffer from these limitations but from a comparably low Aq may have a total performance DQE(f) comparable to that of traditional screen-film based, image detectors.
Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press , 1998. , 20 p.
Report / Department of Radiology, Linköping University, 1998-, 86
digital mammography, detective quantum efficiency (DQE), signal-tonoise ratio (SNR), Monte Carlo calculations, silicon detectors
Radiology, Nuclear Medicine and Medical Imaging
IdentifiersURN: urn:nbn:se:liu:diva-57821ISRN: LIU-RAD-R-086OAI: oai:DiVA.org:liu-57821DiVA: diva2:327851