The window mil artefact decrease device and the method in multiple slice CT reconstructing

摘要

A cone or wedge-beam CT scanner (10) generates image data which is potentially artifacted with windmill artifacts which appear to emanate from one or more windmill artifact centers (48). The image data is high-pass filtered (42), and reconstructed (44) to generate an image representation (46) which depicts the windmill artifact centers (48), and a background field (54). A forward projection processor (66) forward projects this image representation to identify data trajectories or rays (60, 62, 64) which pass through a windmill artifact center, a penumbra, or only through the field. Each element of image data is filtered both with a resolution sharpening filter (70) and with a smoothing filter (72). The sharpened and the smoothed data values corresponding to a common ray are weightedly combined (74) in accordance with whether the corresponding common ray passes through a windmill artifact center or only through the field. The weightedly combined filtered data values are reconstructed (66) into an image representation.