A system for determining a transformation between different coordinate systems associated with different medical image data, comprising: - a landmark input for obtaining first coordinates representing a first set of anatomical landmarks obtained from first medical image data in a first coordinate system and second coordinates representing a second set of anatomical landmarks obtained from second medical image data in a second coordinate system; - a matching subsystem configured for: providing reference coordinates representing a reference set of anatomical landmarks in a reference coordinate system, wherein the reference set of anatomical landmarks represents a predefined set of anatomical landmarks encountered in medical imaging of a particular anatomical structure and at least comprises the first set of anatomical landmarks and the second set of anatomical landmarks; and determining a transformation between the first coordinate system and the second coordinate system by: i) determining a first intermediate transformation between the first coordinate system and the reference coordinate system by matching the first set of anatomical landmarks to the reference set of anatomical landmarks; ii) determining a second intermediate transformation between the second coordinate system and the reference coordinate system by matching the second set of anatomical landmarks to the reference set of anatomical landmarks; and iii) combining the first intermediate transformation and the second intermediate transformation to obtain the transformation. - a landmark input for obtaining first coordinates representing a first set of anatomical landmarks obtained from first medical image data in a first coordinate system and second coordinates representing a second set of anatomical landmarks obtained from second medical image data in a second coordinate system; - a matching subsystem configured for: providing reference coordinates representing a reference set of anatomical landmarks in a reference coordinate system, wherein the reference set of anatomical landmarks represents a predefined set of anatomical landmarks encountered in medical imaging of a particular anatomical structure and at least comprises the first set of anatomical landmarks and the second set of anatomical landmarks; and determining a transformation between the first coordinate system and the second coordinate system by: i) determining a first intermediate transformation between the first coordinate system and the reference coordinate system by matching the first set of anatomical landmarks to the reference set of anatomical landmarks; ii) determining a second intermediate transformation between the second coordinate system and the reference coordinate system by matching the second set of anatomical landmarks to the reference set of anatomical landmarks; and iii) combining the first intermediate transformation and the second intermediate transformation to obtain the transformation. providing reference coordinates representing a reference set of anatomical landmarks in a reference coordinate system, wherein the reference set of anatomical landmarks represents a predefined set of anatomical landmarks encountered in medical imaging of a particular anatomical structure and at least comprises the first set of anatomical landmarks and the second set of anatomical landmarks; and determining a transformation between the first coordinate system and the second coordinate system by: i) determining a first intermediate transformation between the first coordinate system and the reference coordinate system by matching the first set of anatomical landmarks to the reference set of anatomical landmarks; ii) determining a second intermediate transformation between the second coordinate system and the reference coordinate system by matching the second set of anatomical landmarks to the reference set of anatomical landmarks; and iii) combining the first intermediate transformation and the second intermediate transformation to obtain the transformation. i) determining a first intermediate transformation between the first coordinate system and the reference coordinate system by matching the first set of anatomical landmarks to the reference set of anatomical landmarks; ii) determining a second intermediate transformation between the second coordinate system and the reference coordinate system by matching the second set of anatomical landmarks to the reference set of anatomical landmarks; and iii) combining the first intermediate transformation and the second intermediate transformation to obtain the transformation.