Patent ID: 7308072
Filing Date: 2007-12-11
Classification: A61B,G01N,G06T

Abstract:
1. A computer tomography device, comprising: a radiographic source; a detector; and an evaluation unit connected to and arranged downstream of the detector for determining scatter information using a plurality of projection images provided by the detector, the projection images recorded relative to different projection directions, the evaluation unit configured to correct an x-ray scatter component present in the projection images using the scatter information, wherein the evaluation unit is further configured to: determine a three-dimensional object model based on the projection images, differentiate the object model according to a plurality of different scatter properties, read out pre-determined scatter information from a data memory based on the object model, wherein the scatter information are pre-determined using a Monte-Carlo-Simulation including interactions of photons with the object model and are stored in the data memory, determine a proportion of the x-ray scatter component present in an image area of a projection image by calculating and summing up x-ray scatter contributions related to further image areas surrounding the image area, and determine a distribution of the unscattered primary radiation by solving the implicit equation P+S(P)=T, where P is the distribution of the unscattered primary radiation, S(P) is the distribution of the x-ray scatter component depending on the unscattered primary radiation and T is an overall x-ray scatter distribution present in the projection images.