Use of a digital phantom developed by QIBA for harmonizing SUVs obtained from the state-of-the-art SPECT/CT systems: a multicenter study

EJNMMI Research

Table 1 Imaging conditions and collimator configurations regarding the four state-of-the-art SPECT/CT systems

	Brightview XCT	Discovery NM/CT 670	Infinia Hawkeye 4	Symbia T6
Imaging condition
Step and shoot image acquisition
No. of step	30	30	30	30
Rotation angle	6	6	6	6
No. of projection	60	60	60	60
Scan orbit	body contour	body contour	body contour	body contour
Size for image acquisition
Matrix (x, y, z)	132, 132, 132	128, 128, 128	128, 128, 128	128, 128, 128
Pixel size and slice thickness (mm)	4.7	4.4	4.4	4.8
Smoothing filter	3D Gaussian	3D Gaussian	3D Gaussian	3D Gaussian
Reconstructed image for ROI analysis
Matrix (x, y, z)	256, 256, 203	256, 256, 207	256, 256, 130	256, 256, 187
Pixel size and slice thickness (mm)	2.0	2.0	2.2	2.0
Energy window
Main	140.5 keV ± 10%	140.5 keV ± 10%	140 keV ± 10%	140 keV ± 10%
Sub	N.A.	120 keV ± 5%	120 keV ± 5%	120 keV ± 5%
Attenuation correction	CT-based	CT-based	CT-based	CT-based
Scatter correction	ESSE	DEW	DEW	DEW
Collimator
Type	CHR	LEHR	LEHR	LEHR
No. of holes (thousand)	40.2	86.3	86.3	148
Hole shape	Hexagon	Hexagon	Hexagon	Hexagon
Hole length (mm)	48	35	35	24.1
Septal thickness (mm)	0.15	0.20	0.20	0.16
Hole diameter across the flats (mm)	2.03	1.50	1.50	1.11

ESSE effective source scatter estimation method. DEW dual-energy window method, CHR cardiac high-resolution collimator, LEHR low-energy high-resolution collimator, N.A. not applicable