Monte Carlo performance on the x-ray converter thickness in digital mammography using software breast models

dc.contributor.author	Λιαπαρίνος, Παναγιώτης Φ.	el
dc.contributor.author	Bliznakova, Kristina S.	en
dc.date.accessioned	2015-06-05T16:13:35Z
dc.date.available	2015-06-05T16:13:35Z
dc.date.issued	2015-06-05
dc.identifier.uri	http://hdl.handle.net/11400/15149
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.source	http://scitation.aip.org/content/aapm/journal/medphys	en
dc.subject	Breast models
dc.subject	Contrast threshold
dc.subject	Mammography
dc.subject	Monte Carlo method
dc.subject	X-ray converters
dc.subject	Μοντέλα μαστού
dc.subject	Αντίθετα όρια
dc.subject	Μαστογραφία
dc.subject	Μέθοδος Μόντε Κάρλο
dc.subject	Μετατροπείς X-ray
dc.title	Monte Carlo performance on the x-ray converter thickness in digital mammography using software breast models	en
heal.type	journalArticle
heal.classification	Medicine
heal.classification	Radiography
heal.classification	Ιατρική
heal.classification	Ακτινογραφία, Ιατρική
heal.classificationURI	http://id.loc.gov/authorities/subjects/sh00006614
heal.classificationURI	http://skos.um.es/unescothes/C03267
heal.classificationURI	N/A-Ιατρική
heal.classificationURI	N/A-Ακτινογραφία, Ιατρική
heal.keywordURI	http://id.loc.gov/authorities/subjects/sh85087032
heal.identifier.secondary	DOI: http://dx.doi.org/10.1118/1.4757919
heal.language	en
heal.access	campus
heal.recordProvider	Σχολή Τεχνολογικών Εφαρμογών. Τμήμα Μηχανικών Βιοϊατρικής Τεχνολογίας Τ.Ε.	el
heal.publicationDate	2012
heal.bibliographicCitation	Liaparinos, P. and Bliznakova, K. (2012) Monte Carlo performance on the x-ray converter thickness in digital mammography using software breast models. "Medical Physics", 39 (11). Available from: http://scitation.aip.org/content/aapm/journal/medphys/39/11/10.1118/1.4757919 [Accessed: 05/06/2015].	en
heal.abstract	Purpose: In x-raymammography, some of the components that play significant role to early diagnosis are the x-ray source, the breast composition as well as the composition of the x-ray converter. Various studies have previously investigated separately the influence of breast characteristics and detector configuration on the optimization of mammographicimaging systems. However, it is important to examine the combined effect of both components in improving the signal transfer properties in mammography systems of the mammograms. In the present study, the authors compared and evaluated x-ray converters using software breast models and realistic mammographicspectra in terms of: (a) zero-frequency detective quantum efficiency (DQE) and (b) sensitivity. The impact of x-ray converter thickness on contrast threshold (CTH) for observer assessment, based on the Rose model, was demonstrated as well. Methods: Monte Carlo techniques were applied to simulate the x-ray interactions within the software breast phantoms and thereafter within the detective medium. Simulations involved: (a) two mammographicx-ray spectra: 28 kV Mo, 0.030 mm Mo, and 32 kV W, 0.050 mm Rh of different entrance surface air kerma (ESAK: 3–7 mGy), (b) realistic breast models (dense and fatty) and (c) x-ray converter materials most frequently considered in investigations on energy integrating digital mammographydetectors: the Gd2O2S:Tb granular phosphor, the CsI:Tl structured phosphor, and the a-Se photoconductive layer. Detector material thickness was considered to vary in the range from 50 mg/cm2 up to 150 mg/cm2. Results: The Monte Carlo study showed that: (a) the x-ray beam becomes less penetrating after passing through dense breasts leading to higher values of zero-frequency DQE of the x-ray imaging converters and improved CTH values in all cases considered, (b) W/Rh target/filter combination results in improved CTH values at higher ESAK values, and (c) a-Se shows higher zero-frequency DQE values than the phosphor-based converters, Gd2O2S:Tb and CsI:Tl. However, thicker layers of CsI:Tl could be comparable to a-Se layers achieving approximately 27.6% CTH improvement at a thickness of 150 mg/cm2. Conclusions: The present Monte Carlo investigation indicates that in the energy range employed in mammography, an upper limit, approximately 100 mg/cm2, should be considered in the development of thicker a-Se converters. On the other hand, above this thickness value, CsI:Tl converter could improve its imaging performance.	en
heal.publisher	Williamson. Jeffrey F.	en
heal.journalName	Medical Physics	en
heal.journalType	peer-reviewed
heal.fullTextAvailability	true