Towards standardization of x-ray beam filters in digital mammography and digital breast tomosynthesis: Monte Carlo simulations and analytical modelling.

摘要: In digital breast tomosynthesis and mammography, the x-ray beam filter material thickness vary between systems. Replacing K-edge filters with Al was investigated intent to reduce exposure duration simplify system design. Tungsten target spectra were simulated (50 µm Rh; 50 Ag) of varying thickness. Monte Carlo simulations conducted quantify scatter from various alone, scatter-to-primary ratio (SPR) compressed breasts, determine radiation dose breast. These data used analytically compute signal-difference-to-noise (SDNR) at unit (1 mGy) mean glandular (MGD) for W/Rh W/Ag spectra. At SDNR matched filtered spectra, reductions in MGD quantified three strategies: (i) fixed tube potential kilovolts (kV); (ii) kV match half-value layer (HVL) spectra; and, (iii) HVL indicate that SPR without not different filters. Modelling (700 µm) identical achieved 37-57% reduction 2-20% MGD, depending on by increasing over (0,4) range, 62-65% decrease 2-24% For (700, 880) 23-56% increased fluence or variable substantially decreases while providing similar image quality moderate MGD.