X-ray CT apparatus and image reconstruction method

摘要

To generate a reconstructed image suitable to characteristics of a bilaterally symmetric site and possible to an appropriate image diagnosis, a computation device: computes a back projection phase width at a rotational center and distance between the rotational center location which is a reference location and a pixel to be reconstructed; according to the distance between the rotational center location and the pixel to be reconstructed, sets a function (f1) changing the back projection phase width; computes a back projection phase width in the pixel to be reconstructed, substituting a value of the distance between the rotational center location and a pixel to be reconstructed in the function (f1); computes a view weighting, on the basis of the back projection phase width in the post-correction pixel to be reconstructed and a slope width of a view weighting function; and reconstructs a CT image, using the view weighting.

主权项

1. An X-ray CT apparatus comprising:
an X-ray generation device including a cathode and anode, to irradiate an X-ray from around a test object; an X-ray detection device including plural detectors to detect the X-ray penetrating the test object; a data collection device that collects data detected by the X-ray detection device; and a computation device that inputs the data collected by the data collection device to create projection data and reconstructs a CT image using the projection data, wherein the computation device calculates a back projection phase width in each pixel on the basis of a reduction rate of the back projection phase width relative to a reference position regulated by one or more reference points on an axial plane at a position apart from the reference position only by a reference distance, calculates a view weight using the back projection phase width in each pixel, and reconstructs the CT image using the view weight.