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 3 Automatic exposure control repeatability: maximum relative error for tube voltage (kV_p), exposure (mAs), calculated MGD and CNR obtained from measurements on the phantom images

Modality	GE Pristina AOP/STD	GE Pristina AOP/STD +	GE Pristina AOP/DOSE	Hologic Dimensions AutoFilter	Hologic 3Dimensions AutoFilter
DM	kV_p 0.00% mAs 2.25% MGD 2.27% CNR 1.77%	kV_p 0.00% mAs 1.60% MGD 1.51% CNR 1.49%	kV_p 0.00% mAs 1.92% MGD 1.74% CNR 3.35%	kV_p 0.00% mAs 2.14% MGD 2.06% CNR 1.28%	kV_p 0.00% mAs 2.46% MGD 2.39% CNR 1.07%
DBT	kV_p 0.00% mAs 1.86% MGD 2.22% CNR 2.56%	kV_p 0.00% mAs 1.37% MGD 1.75% CNR 1.68%	−	kV_p 0.00% mAs 1.36% MGD 0.50% CNR 2.32%	kV_p 0.00% mAs 1.30% MGD 1.35% CNR 1.41%
CEM
LE	kV_p 0.00% mAs 1.17% MGD 1.20% CNR 1.20%	−	−	−	kV_p 0.00% mAs 3.03% MGD 3.14% CNR 2.25%
HE	kV_p 0.00% mAs 1.30% MGD 1.15% CNR 1.79%				kV_p 0.00% mAs 3.57% MGD 3.74% CNR 2.94%

The reported error values represent the highest variation observed across the entire range of phantom thicknesses for all three mammography systems and their respective modalities, along with the automatic exposure modes available for each modality. CEM Contrast-enhanced mammography, CNR Contrast-to-noise ratio, DBT Digital breast tomosynthesis, DM Digital mammography, MGD Mean glandular dose