1. A computed tomography (CT) reconstruction method comprising: reconstructing an axially extended reconstructed image from a measured cone beam x-ray projection data set acquired during rotation of an x-ray source in a rotation plane around an axial axis, the reconstructing being performed for an extended volume comprising (i) a reconstructable volume of the measured cone beam x-ray data set within which each voxel is probed by projections of the measured cone beam x-ray projection data set over at least 180° and (ii) an additional volume extending beyond the reconstructable volume along the axial direction; and generating a reconstructed image by axial truncation of the axially extended reconstructed image.