Skip to main content
. Author manuscript; available in PMC: 2013 Nov 7.
Published in final edited form as: Phys Med Biol. 2012 Oct 3;57(21):6827–6848. doi: 10.1088/0031-9155/57/21/6827

Table 1.

Definitions of the variables used in this work, listed in the sequence of appearance.

Variables Definitions
x, y, z Coordinates of the PET image space reference frame XYZ.
r, u The in-plane variables of the LOR-PDF function. The r and u axes are parallel to x
and z axes, respectively.
d The depth variable along LOR, starts from one predetermined (e.g., higher
detector block index) end of LOR.
j, J Image voxel index, and the number of image voxels, respectively.
i, I LOR index, and the number of LORs, respectively.
Vi The rectangular tube volume of LORi.
p() Probability density function.
cij Probability of emission from voxel j contributing to LOR i.
φ, θ In-plane and out-of-plane orientation angle of LOR at the starting-side of LOR.
b The separation between a LOR’s ending and starting side detector block indices.
N The number of detector blocks in a detector ring.
L Length of LOR
D Diameter of detector ring