An X-ray CT apparatus, a method for changing the helical pitch, an image reconstruction processing apparatus, an image reconstruction processing method, and an image reconstruction processing program
The X-ray CT apparatus that performs a scan after a pre-scan, comprising a reconstruction part reconstructing the pre-scan image of said subject to be examined from transmission data detected by said detector during said pre-scan, and also reconstructing the scan image of said subject to be examined from the transmission data detected by said detector during said scan and a scan controlling part initiating a scan by directly changing the helical pitch of said bed from the stopped position for said pre-scan to the position toward an ending edge of the reconstruction area of the image. The scan controlling part initiates the scan at a first helical pitch by which X-rays for a predetermined number of views can be emitted at a starting edge of the reconstruction area of the image, and, after X-rays for the predetermined number of views is emitted, the scan at a second helical pitch continues.
