Monte Carlo derivation of filtered tungsten anode X-ray spectra for dose computation in digital mammography.

Objective: Derive filtered tungsten X-ray spectra used in digital mammography systems by means of Monte Carlo simulations.

Materials And Methods: Filtered spectra for rhodium filter were obtained for tube potentials between 26 and 32 kV. The half-value layer (HVL) of simulated filtered spectra were compared with those obtained experimentally with a solid state detector Unfors model 8202031-H Xi R/F & MAM Detector Platinum and 8201023-C Xi Base unit Platinum Plus w mAs in a Hologic Selenia Dimensions system using a direct radiography mode.

Dosimetry and image quality assessment in a direct radiography system.

Objective: To evaluate the mean glandular dose with a solid state detector and the image quality in a direct radiography system, utilizing phantoms.

Materials And Methods: Irradiations were performed with automatic exposure control and polymethyl methacrylate slabs with different thicknesses to calculate glandular dose values. The image quality was evaluated by means of the structures visualized on the images of the phantoms.

Comparison of mean glandular dose values provided by a digital breast tomosynthesis system in Brazil.

Studies are needed to determine the radiation dose of patients that are undergoing Digital breast tomosynthesis (DBT) procedures. Mean glandular dose (DG) values were derived from the incident air kerma (Ki) measurements and tabulated conversion coefficients. Ki values were obtained through an ionization chamber positioned in a Hologic Selenia Dimensions system using appropriate exposure parameters.