the embodiments relate to generating a 2d projection image of a vascular system of a body region of interest , including : acquiring a 3d dataset of the body region of interest , acquiring at least one 2d projection image of the body region of interest , generating a modified 3d dataset by eliminating vessels whose size exceeds a predetermined limit value , normalizing the 2d projection image using projection data of the modified 3d dataset , eliminating vessel projections in the normalized 2d projection image whose size exceeds a predetermined limit value , interpolating the areas of the 2d projection image in which the vessel projections have been eliminated , and denormalizing the normalized and interpolated 2d projection image using projection data of the modified 3d dataset .