Table 2.

Acquisition and reconstruction parameters used in the phantom experiments.

Scan parameters	SECT	DECT		PCD-CT	PCD-CT
				Four-energy mode	Two-energy mode
kV	120	80/Sn140	100/Sn140	140	140
Detector type	EID	EID		PCD	PCD
Collimation (mm)	$128\times 0.6$	$32\times 0.6$		$32\times 0.5$	$32\times 0.5$
Pitch	0.7	0.6		0.6	0.6
Thresholds (keV)	N/A	N/A		[20,31,55,90]	[25, 65]
				[20,25,57,77]
				[20,39,64,89]
				[25,45,65,85]
Image thickness/interval (mm)	1.5/1.0	1.5/1.0		1.5/1.0	1.5/1.0
Recon kernel	B40	D30		D30	D30
Recon FOV (mm)	200	200		200	200
CTDIvol (mGy)	RD: 3.82	RD: 3.52	RD: 3.53	RD: 8.68	RD: 3.88
		HD: 18.50	HD: 28.13	HD: 60.74	HD: 60.74

Note: EID, energy integrating detector; PCD, photon-counting detector; FOV, field of view; RD, routine radiation dose; HD, highest radiation dose. Dose values are in terms of volume CT dose index (CTDIvol) and are based on the 32-cm diameter phantom.