A process for the reconstruction of a three-dimensional image data set from two-dimensional projection images, x-ray apparatus and computer program

摘要

A process for the reconstruction of a three-dimensional image data set from under different projection directions recorded, two-dimensional projection images, wherein– the projection images using one of a for receiving utilized x-ray source is connected downstream of the collimator for the limitation does not attenuated x-radiation on an image region of interest (2) and were recorded– in the reconstruction by means of the filtered backprojection in the filtering step instead of a ramps filter first a local laplace - filter on the projection data of the projection images is used, after which, in the laplace filtered projection data on limits (3) to the image region (2) resulting high-frequency tips (11) by a pointed filter may be removed and a global, in particular the tips filter integral containing a radon based residual filter is used, of the laplace - filter to a ramps filter, with in a first correction step a the projection data of course in the uncorrected projection images within the image region (2) described in the fit function approximating fit parameters starting from at least at the boundaries (3) present boundary values of the projection data is determined, and in a second, to the use of the residual filter subsequent correction step an additive correction of the residual filtered projection data in the image region (2) with the scaled fit function by a scaling factor is carried out.