Experimental evaluation of the image quality and dose in digital mammography: Influence of x-ray spectrum. (November 2015)

• Record Type: Journal Article
• Authors: Tomal, A.; Perez, A.M.M.M; Silva, M.C.; Poletti, M.E.
• Is Part Of: Radiation physics and chemistry. Volume 116(2015:Nov.)
• Page Start: 282
• Page End: 286
• Publication Date: 2015-11
• Subjects: Digital mammography -- Contrast-to-noise ratio -- Mean glandular dose -- x-ray spectra -- Figure of Merit; Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2015.04.019
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: In this work, we studied experimentally the influence of x-ray spectrum on the contrast-to-noise ratio (CNR) and the average glandular dose (MDG) for two digital mammography systems: Senographe 2000D (GE Medical Systems) and Lorad Selenia (Hologic), with indirect and direct detector imaging technology, respectively. CNR and MGD were determined using PMMA phantoms simulating breasts with thicknesses of 4 cm and 6 cm. All available anode/filter combinations of the systems were evaluated for a wide range of tube voltages values. Results indicated that the Rh/Rh combination provides the highest image quality with the lower mean glandular dose for the Senographe 2000D system. For the Lorad Selenia system, the W/Ag combination at 30 kV showed the best performance, in terms of dose saving and image quality improvement in relation to all tube voltage range. The comparison between the optimal x-ray spectra and those selected by the AEC mode showed that this automatic selection mechanism could be readjusted to optimize the relationship between image quality and dose. Abstract : Highlights: CNR and MGD were studied for different x-ray spectra in two mammographic systems. The optimum x-ray spectrum for each system was determined using a FOM. The results were compared with those obtained using the AEC mode AEC mechanism could be readjusted to optimize the relationship between CNR and MGD.