X-RAY CT DATA PROCESSING DEVICE AND X-RAY CT DEVICE COMPRISING SAME

The purpose of the present invention is, when carrying out multi-energy photography with an energy-separation detector and creating an image in which a subject is separated into a plurality of standard substances, to estimate the appropriateness of posited standard substances and determine with good precision that appropriate standard substances are present in said subject. An X-ray CT data processing device, which processes CT data which is acquired in each of a plurality of detected energy ranges and creates a reconstructed image which is separated into prescribed standard substances, comprises: a standard substance data computation unit which, using different combinations of a plurality of instances of the CT data, computes, for each of a plurality of standard substances, physical quantities which are not energy-dependent, creating a plurality of instances of standard substance data for the same standard substance; and an appropriateness determination index creation unit which, on the basis of the pluralit