The invention relates to a CT system (1) comprising an image fusion unit (12) for generating a fusion image being a fusion of a CT image of an object (5) within a CT imaging region (6), particularly within a bore (13) of the CT system, and of an optical image of the object, which is generated, after the object has been moved out of the CT imaging region, particularly when the object is located in front of the bore. The fusion image further shows a path, along which an interventional instrument (26) should be moved within the object (5) and which has been provided based on the CT image. By looking at the fusion image a user can accurately move the instrument along the path, without needing to acquire many additional CT images for position checking purposes. This can reduce the radiation dose and time needed for an interventional procedure.
