TABLE 1

Collimator Specifications in Experimental Hoffman Brain Imaging

Collimator type	Focal length^* (cm)	Hex hole size (cm)	Septal thickness (cm)	Hole length (cm)	Resolution FWHM^† (cm)	Point source sensitivity^† (counts/s)/kBq
PB	Infinity	0.138	0.016	4.54	0.65	164.28
FB	39	0.122	0.015	4.13	0.56	255.30
HCB	50	0.145	0.022	4.00	0.66	447.70

↵* Measured from collimator surface.
↵† Measured in air on transaxial focal plane at 12.5 cm from collimator surface.
FB = fanbeam.