COMPENSATION OF COMPUTED TOMOGRAPHYDATA FOR OBJECTS POSITIONED OUTSIDETHE FIELD OF VIEW OF THE RECONSTRUCTED IMAGE

摘要

An x-ray CT system acquires attenuation data over a field of view which is larger than the field of view of the reconstructed image. The data used to reconstruct the image is compensated for the shading effects otherwise caused by objects outside the image, but within the x- ray path. This compensation is accomplished with minimal impact on computation time by using a first order estimation of the convolution of the acquired attenuation data outside the image field of view.