TABLE 3

State-of-the-Art PET Scanners: Physical Performance (Factory Data)

Performance	ALLEGRO (Philips-ADAC)	C-PET (Philips-ADAC)	ECAT ART (CTI-Siemens)	ECAT EXACT (CTI-Siemens)	ECAT EXACT HR+ (CTI-Siemens)	ECAT ACCEL (CTI-Siemens)	ADVANCE/ADVANCE Nxi (General Electric)
Transaxial resolution
FWHM (mm) at 1 cm					4.6 (2D)	6.2 (2D)
	4.8*	5.0*	6.2	6.0 (2D/3D)	4.5 (3D)*	6.3 (3D)*	4.8 (2D/3D)
FWHM (mm) at 10 cm					5.4 (2D)	6.7 (2D)
	5.9*	6.4*	6.9	6.7 (2D/3D)	5.6 (3D)*	7.4 (3D)*	5.4 (2D/3D)
Axial resolution
FWHM (mm) at 0 cm				4.5 (2D)	4.2 (2D)	4.3 (2D)	4.0 (2D)
	5.4*	5.5*	4.9	4.6 (3D)	4.2 (3D)*	5.8 (3D)*	4.7 (3D)
FWHM (mm) at 10 cm				5.9 (2D)	5.0 (2D)	6.0 (2D)	5.4 (2D)
	6.5*	5.9*	6.6	6.5 (3D)	5.7 (3D)*	7.1 (3D)*	6.3 (3D)
System sensitivity				4.9 (2D)	5.4 (2D)	5.4 (2D)	5.4 (2D)^†
(net trues) (cps/Bq/mL)	19.0*	12.1*	7.3	21.1 (3D)	24.3 (3D)	27.0 (3D)	31.0 (3D)^‡
Scatter fraction (%)				16 (2D)	17 (2D)	16 (2D)	10 (2D)
	25	25	36	36 (3D)	36 (3D)	36 (3D)	35 (3D)

↵* Assessed according to NEMA NU 2-2001 (11).
↵^† Measured at 300-keV LLD in high sensitivity mode.
↵^‡ Measured at 300-keV LLD.
All parameters were measured following NEMA NU 2-1994 (10) whenever not specified.