At least one embodiment of the present invention relates to a method and/or an apparatus for determining the spatial profile of a vessel axis in volume data records for medical imaging, in particular for producing slice images of vessels which are obtained by curved planar reformation CPR and can be rotated freely. In at least one embodiment of the method, the vessel axis is marked interactively on the displayed MPR or MIP images by marking points using a two-dimensional coordinate system. Depth information is derived automatically for each marking point from the known position of the respective image in the stack or using the known calculation procedure for MIP images, and the marking points are extended in dimension on the basis of the depth information in order to obtain extended marking points using a three-dimensional coordinate system. The three-dimensional profile of the vessel axis, which is used for producing CPR images which can be rotated freely, is then obtained by linking the extended marking points. The method makes it possible, in at least one embodiment, to determine the profile of the vessel axis with less time and computation effort.