Retrieving patient orientation from previous images

The present invention relates to re-positioning in medical imaging. In order to facilitate the re-positioning of a patient in relation to an X-ray imaging system, it is proposed to provide (12) previously acquired first image data (14) of a patient in a first spatial position in relation to an X-ray image acquisition device. Current second image data (18) with the X- ray image acquisition device of the patient in a second spatial position in relation to the X-ray image acquisition device is acquired (16). One of the first or second image data is a 3D volume data of the patient, and the other one of the second or first image data is 2D or 3D image data of the patient. Further, the first image data and the second image data are registered (20). Next, a relative movement factor (24) between the first and the second spatial position is determined (22). Then, the patient and the X-ray image acquisition device in relation to each other are re-positioned (26) in a re-positioned relative spatial position based on the determined relative movement factor for movement compensation to achieve a predetermined matching degree of the re-positioned spatial position with the first spatial position for the acquisition of further image data.