Patent ID: 7792240
Filing Date: 2010-09-07
Classification: A61B

Abstract:
1. An x-ray CT apparatus comprising: an X-ray tube configured to generate X-rays for irradiating an object to be examined; an X-ray detector configured to measure an X-ray dosage transmitted through the object; a turntable configured to rotate the X-ray tube and the X-ray detector a specific rotation angle around the object, the x-ray tube and the x-ray detector being mounted facing each other on the turntable; projection data calculation means for calculating projection data of the object from the X-ray dosage measured by the X-ray detector; reconstruction means for reconstructing a tomogram of the object using the calculated projection data; tomogram storage means for storing the reconstructed tomogram of the object; association storage means for associating the projection data calculated by the projection data calculation means with a phase information of a moving region of the object having periodic motions, and storing both the phase information and the projection data associated with the phase information; target tomogram construction means for constructing a target tomogram of the object corresponding to desired phase information stored in the association storage means, and using the projection data associated with the desired phase information; tomogram group creation means for creating a first tomogram group by summing at least one tomogram corresponding to the desired phase information, and a second tomogram group by summing at least one tomogram corresponding to other phase information different from the desired phase information of the first tomogram group; and movement-degree acquisition means for acquiring a degree of movement of a pixel value of each pixel of the target tomogram, wherein said target tomogram construction means constructs the target tomogram by performing weighting addition on the first and the second tomogram groups in each pixel according to the degree of movement of the pixel value acquired by the movement-degree acquisition means.