The method involves implementing mask operation of tomographs around a body part, where the body part is examined without a contrast medium. Filling operations of the tomographs are implemented around the body part using the contrast medium. Data from the filling operations is combined to a data record. Data record received during the mask operation is subtracted from the data record for receiving a final data record, where the data record contains the data for a three-dimensional representation of arteries or the veins of a vascular system. An independent claim is also included for a device for separate three-dimensional imaging of arteries and/or veins of a vascular system in a body part of a vertebrate.
