GEOMETRIC CALIBRATION MARKER DETECTION IN SPECTRAL TOMOSYNTHESIS SYSTEM

A method for geometric calibration of a volume imaging apparatus disposes calibration phantom in a radiation path that includes a subject positioned between an x-ray source and a detector. The phantom has a number of radio-opaque markers formed of a marker material. In a repeated sequence, at each of a number of positional relationships of the x-ray source to the detector: 2D projection image data is acquired for the subject and the phantom, wherein the 2D projection image data distinguishes at least first and second x-ray energy distributions; source-to-detector geometry of the imaging apparatus is calculated, corresponding to the acquired 2D projection image data for the first and second x-ray energy distributions. The method reconstructs and displays a 3D volume image of the subject according to acquired anatomy image data from the subject and source-to-detector geometry within the 2D projection images.