A data processing device for connection to a diagnostic medical imaging device (DMID) and an interventional medical imaging device (IMID), the data processing device being provided with program instructions for making the data processing device perform the steps of: - receiving, from the diagnostic medical imaging device, diagnostic medical image data representing a diagnostic medical image of the tissue of the patient; - segmenting, using an image segmentation criterion, in the diagnostic medical image data a diseased area image data representing a diseased area of the tissue; - defining, in the segmented diagnostic medical image data, a treatment surface of the tissue; - projecting the diseased area, represented by the diseased area image data, onto the treatment surface; - defining a treatment location on the treatment surface, the treatment location being in, out or at a boundary of the diseased area projected onto the treatment surface; - registering data representing the treatment surface and the treatment location at an interventional medical imaging device; - providing instructions for positioning the interventional device to face the treatment surface; characterised in that the program instructions are for making the data processing device further perform the steps of: - determining a local tangent plane of the treatment surface of the tissue in the diagnostic medical image data, the local tangent plane being located at the treatment location on the treatment surface; - determining a first direction perpendicular to a normal to the local tangent plane of the treatment surface of the tissue; - providing instructions for imaging, by the interventional medical imaging device, the tissue at the treatment location and at least a neighbouring part of the interventional device to obtain first interventional image data from the first direction; - providing instructions for enhancing, using the first interventional image data, a position of the interventional device in a direction of the normal and in a second direction perpendicular to the normal and perpendicular to the first direction. - receiving, from the diagnostic medical imaging device, diagnostic medical image data representing a diagnostic medical image of the tissue of the patient; - segmenting, using an image segmentation criterion, in the diagnostic medical image data a diseased area image data representing a diseased area of the tissue; - defining, in the segmented diagnostic medical image data, a treatment surface of the tissue; - projecting the diseased area, represented by the diseased area image data, onto the treatment surface; - defining a treatment location on the treatment surface, the treatment location being in, out or at a boundary of the diseased area projected onto the treatment surface; - registering data representing the treatment surface and the treatment location at an interventional medical imaging device; - providing instructions for positioning the interventional device to face the treatment surface; - determining a local tangent plane of the treatment surface of the tissue in the diagnostic medical image data, the local tangent plane being located at the treatment location on the treatment surface; - determining a first direction perpendicular to a normal to the local tangent plane of the treatment surface of the tissue; - providing instructions for imaging, by the interventional medical imaging device, the tissue at the treatment location and at least a neighbouring part of the interventional device to obtain first interventional image data from the first direction; - providing instructions for enhancing, using the first interventional image data, a position of the interventional device in a direction of the normal and in a second direction perpendicular to the normal and perpendicular to the first direction.