Patent ID: 9715745
Date: 2017-07-25
CPC Classifications: A61B,G06T

Claim:
1. An X-ray CT apparatus comprising: an X-ray generating device irradiating an X-ray from the surroundings of an object; an X-ray detection device detecting an X-ray transmitted through the object; a data collection device collecting data detected by the X-ray detection device; an calculation device generating projection data by inputting data to be collected by the data collection device and reconstructing a CT image using the projection data; and a display device displaying the CT image, wherein the calculation device is comprised of: an application range determining unit determining an application range for an iterative approximation projection data correction process that is a correction process by the iterative approximation method which uses a smoothing coefficient showing a correction intensity for the projection data; an iterative approximation projection data correction processing unit performing the iterative approximation projection data correction process for projection data that corresponds to the range determined by the application range determining unit to generate correction projection data; and an image reconstruction unit reconstructing a CT image using the correction projection data, wherein margin regions are set around a range determined by the application range determining unit, and the iterative approximation projection data correction process is performed for projection data corresponding to the margin regions by changing the smoothing coefficient continuously.