. Author manuscript; available in PMC: 2019 Aug 26.

Published in final edited form as: IEEE Trans Radiat Plasma Med Sci. 2018 Oct 23;3(3):334–342. doi: 10.1109/TRPMS.2018.2877511

TABLE I.

Design characteristics of PET scanners used for comparison.

Parameters	UHR	HRRT [17]	Biograph Vision [19]
Scintillator materials	LYSO	LSO/LYSO	LSO
Number of scintillators	129,024	119,808	60,800
Scintillator size (mm³)	1.12 × 1.12 × 12	2.1 × 2.1 × (10 + 10)	3.2 × 3.2 × 20
Scintillator array dimension	4 × 8	72 × 104 (× 2 layers)	10 × 20
Photodetector	APD	PMT	SiPM
Scintillator-to-photodetector ratio	1 : 1	7488 : 140	200 : 128
Scintillators per ring	896	576 (× 2 layers)	760
Number of rings	144	104	80
Axial length (mm)	235	252	263
Ring diameter (mm)	390	469	820
Transaxial FOV (mm)	271	312	700
Packing fraction (%)	56	71	91
Coincidence time window (ns)	6	6	4.73
Energy window (keV)	250–650	350–650	435–650
Dead time (ns)	490	320	320