A method for iterative image reconstruction for Bi-Modal CT data and corresponding arithmetic unit, computer system, computer program and data carrier

A method for reconstructing image data (PIC) of an examination object from measurement data (p), wherein the measurement data (p) at a relative rotational movement between a radiation source (C2, C4) of a computed tomography system (C1) and the object under examination have been detected, from the measurement data (p) first image data (PIC A) with a first image characteristic and second image data (PIC B) is reconstructed with a second image characteristic, with respect to the first image characteristic improved signal-to-noise ratio of the second image characteristic, using the first (PIC A) and second (PIC B) image data using an iterative algorithm (it Recon) improved image data (PIC) are calculated, wherein in the iterative algorithm (it Recon) - a low pass to a difference between the first image data (PIC A) and image data of an iteration, and - a high-pass to a difference between the second image data (PIC B) and the image data of iteration is applied.