In an imaging method and a tomosynthesis apparatus, a two-dimensional low-energy image of the predetermined volume segment is obtained after administration of a contrast agent, followed by a two-dimensional high-energy image and then a high-energy tomosynthesis of the predetermined volume segment is obtained with a high total radiation dose that is significantly higher than the low radiation dose. The two-dimensional low-energy image is subtracted from the two-dimensional high-energy image to generate a result with which the concentration of the contrast agent is visible. Additionally, in a time interval in which an enrichment or a washing-out of the contrast agent occurs within the predetermined volume segment, a tomosynthesis of the predetermined volume segment is automatically implemented to show the concentration of the contrast agent in the predetermined volume segment.