X-ray CT apparatus and X-ray CT image-generating method

摘要

An X-ray detector (320), configured to have X-ray detecting elements (322) arranged in array, detects the intensity of X-rays that are radiated from the X-ray tube (311) and have passed through a subject (500). A data processing device (420) executes steps of: arranging scan data, which is based on the intensity of X-rays, in an array sequence of the X-ray detecting elements (322) or in a time sequence, to detect an anomalous scan data; associating a weight greater than “1” with scan data adjacent to the anomalous scan data, and associating a weight of “1” with other imaging data; calculating an update amount of a pixel vector that reflects these weights; and performing an iterative operation using the update amount to generate an X-ray CT image of the subject (500).

主权项

1. An X-ray CT apparatus comprising:
an X-ray generator that generates X-rays; an X-ray detector that is configured to have multiple X-ray detecting elements arranged in array for detecting intensity of the X-rays; a scanning control unit that transmits detection data detected by the X-ray detecting elements as scan data of a subject; and a data processing device that obtains the scan data transmitted from the scanning control unit, and processes the obtained scan data to generate an X-ray CT image of the subject, wherein the data processing device executes steps of: storing the scan data obtained by the X-ray detecting elements into a storage unit in accordance with an arrangement of the X-ray detection elements in the X-ray detector, and detecting anomalous scan data among the stored scan data; associating a weight with scan data adjacent to the anomalous scan data detected, the weight being greater than a weight associated with other scan data; and calculating pixel data of the X-ray CT image of the subject, through iteration of an iterative operation using a projection matrix defined by data including a layout position of the X-ray generator and arrangement positions of the respective multiple X-ray detection elements, pixel data that has been set at that time, and the scan data, wherein in the iterative operation, when calculating an update amount for the pixel data based on difference data between projection data obtained from the projection matrix and the pixel data at that time, and the scan data, the difference data is weighted with the weight associated with the scan data corresponding to the difference data.