Patent ID: 8340386
Filing Date: 2012-12-25
Classification: A61B,G06T

Abstract:
1. A method for measuring a single photon emission computed tomography collimator's hole orientations, comprising: (a) providing a plurality of parallel spaced apart line radiation sources at a distance from a detector; (b) positioning a first collimator between the plurality of spaced apart line radiation sources and the detector; (c) obtaining a first set of line images of the plurality of line radiation sources by scanning/stepping the plurality of line radiation sources across the first collimator in a first direction; (d) obtaining a second set of line images of the plurality of line radiation sources by scanning/stepping the plurality of line radiation sources across the first collimator in a second direction that is orthogonal to the first direction; (e) repeating the steps (c) and (d) for a second collimator, wherein one of the two collimators is a reference collimator and the other of the two collimators is a collimator being measured, whereby the line images obtained using the reference collimator are reference collimator line images and the line images obtained using the collimator being measured are measured collimator line images; (f) analyzing the reference collimator line images and the measured collimator line images and determining the offset distance dx between the reference collimator line images and the measured collimator line images in the first direction and the offset distance dy between the reference collimator line images and the measured collimator line images in the second direction, wherein dx is the offset distance in the first direction and dy is the offset distance in the second direction; and (g) calculating hole orientation angles θx, θy for each collimator hole in the collimator being measured.