Contrast-enhanced image data of breast tissue to be examined is generated. First two-dimensional contrast-agent-influenced x-ray projection data of the breast tissue are acquired at a first x-ray beam energy and a two-dimensional image data record is generated on the basis of the first two-dimensional x-ray projection data. Second two-dimensional contrast-agent-influenced x-ray projection data are acquired from different projection angles at a second x-ray beam energy that differs from the first x-ray beam energy and a three-dimensional tomosynthesis image data record of the breast tissue is reconstructed from the detected second two-dimensional x-ray projection data. Subsequently, a two-dimensional synthetic mammogram is calculated on the basis of the three-dimensional tomosynthesis image data record and a two-dimensional dual-energy mammogram is established by subtracting the image data of the synthetic mammogram from the image data of the two-dimensional image data record.
