Patent ID: 7492854

Claim:
An X-ray CT apparatus comprising: an X-ray data acquisition device configured to acquire X-ray projection data of an X-ray passed through a subject positioned between an X-ray generator and an opposite multi-row X-ray detector; a CT value adjustment device configured to obtain CT value conversion parameters with respect to each detector row of said multi-row X-ray detector, the CT value conversion parameters used in a CT value conversion process for normalizing CT values of the projection data; and an image reconstruction device configured to reconstruct a tomographic image from the projection data acquired by said X-ray data acquisition device using a three-dimensional back projection process in which the projection data acquired by said multi-row X-ray detector is used to reconstruct the tomographic image, said image reconstruction device further configured to perform the CT value conversion process to the projection data using the CT value conversion parameters prior to a three-dimensional back projection process.