Dosimetry and Comparison between Different CT Protocols (Low Dose, Ultralow Dose, and Conventional CT) for Lung Nodules’ Detection in a Phantom

Table 1

Protocol specifications.

	ULD	LD (lower mA)	LD (lower kV)	Conventional LDCT	HRCT
Gantry rotation time (s)	0.5	0.5	0.5	0.5	0.5
Beam collimation (mm)	40	40	40	40	40
Pitch	0.984	0.984	0.984	0.984	0.984
kV	80	120	100	120	120
mA	30	20	30	30	Auto/smart mA