X-ray CT apparatus including a photon-counting detector, and an image processing apparatus and an image processing method for correcting detection signals detected by the photon-counting detector
An X-ray computed tomography (CT) apparatus according to an embodiment includes a photon-counting detector, correction circuitry, and reconstruction circuitry. The photon-counting detector includes a plurality of X-ray detection elements detecting X-ray photons applied from an X-ray tube. The correction circuitry corrects detection signals detected by the photon-counting detector for the respective X-ray detection elements, based on a centroid of an X-ray spectrum detected by the photon-counting detector. The reconstruction circuitry reconstructs a CT image based on the corrected detection signals.