Patent ID: 6243439
Filing Date: 2001-06-05
Classification: A61B

Abstract:
A CT scanning apparataus comprising an image pickup system having an X-ray source being rotated along a circular orbit around an object and a two-dimensional X-ray image pick portion disposed opposite to said X-ray source with a direction of X-ray radiation extending from said X-ray surce to said image pickup portion and with said object therebetween and being rotated along a circular orbit, and being configure to rotate said image pick up system so as to radiograph three-dimensional areas inside said object, said apparatus further comprising a substance capable of being detected as an X-ray image used as a position marker, said position marker being disposed so as to be positioned in the image pickup view of said image pickup system during the rotation of said image pickup system and radiographed together with said object, means for calculating a correction amount for each X-ray image from the position of the image of said position marker in an obtained two-dimensional X-ray image on a plane perpendicular to said direction of X-ray irradiation, a means for correcting said two-dimensional X-ray image by using said correction amount, and a means for building a CT image from said corrected two-dimensional X-ray image whereby image quality of the two-dimensional X-ray image is improved.