. Author manuscript; available in PMC: 2008 Dec 2.

Published in final edited form as: IEEE Trans Med Imaging. 2007 Jul;26(7):935–944. doi: 10.1109/TMI.2007.895485

TABLE I.

Parameters and Labels for Partially Collimated Systems Drawings for these Systems are Shown in Fig. 3

Label:	2D	‘2.1D’	‘2.3D’	‘2.5D’	‘2.7D’	‘2.9D’	3D
# septa removed	0	2	5	9	12	15	17
# septa in collimator	17	15	12	8	5	2	0
septal gap^* [mm]	7.5	7.5/ 16^**	7.5/ 16^**	16	24.5	50	152

The septal gap describes the air space in between opposing septa or septa and end shields.

^**

No even septa spacing