Phantom-based analysis of variations in automatic exposure control across three mammography systems: implications for radiation dose and image quality in mammography, DBT, and CEM

European Radiology Experimental

Table 1 Main physical characteristics of the three mammography systems compared

System	Senographe Pristina	Selenia Dimensions	Selenia 3Dimensions
Manufacturer	GEHC	Hologic	Hologic
Detector type	CsI FPD	a-Se FPD	a-Se FPD
Pixel pitch (μm)	100	70 (2 × 2 binning in DBT)	70
Modalities	DM DBT CEM	DM DBT	DM DBT CEM
Anode(s)	Mo and Rh	W	W
Filter(s)	Mo, Ag, Cu^a	Rh, Ag, Al^b, Cu^a	Rh, Ag, Al^b, Cu^a
DBT protocol
Tube motion	Step-and-shoot	Continuous	Continuous
Projections	9	15	15
Angle	25° (± 12.5°)	15° (± 7.5°)	15° (± 7.5°)
Geometry	Partial isocentric	Full isocentric	Full isocentric
Scatter	Grid	No Grid	No Grid
N° AEC modes	DM: 3 (AOP/STD, AOP/STD+ , AOP/DOSE) DBT: 2 (AOP/STD, AOP/STD+) CEM: 1 (AOP/STD)	1 (AutoFilter)	1 (AutoFilter)

AOP/STD, AOP/STD+ , AOP/DOSE, AutoFilter are the names given by the two manufacturers to their AEC modes
FPD Flat panel detector, CsI Cesium iodine, a-Se Amorphous selenium, DM Digital mammography, DBT Digital breast tomosynthesis, CEM Contrast-enhanced mammography, AEC Automatic exposure control
^aCu filter is used by both systems (GE Pristina and Hologic 3Dimensions) for the only high-energy image in CEM mode
^bAl filter is used by Hologic systems in DBT mode