these three elements to each other the spatial orientation of the device can be calculated and then be integrated in the mr image better still is the application of markers which are directly identified by the u201c magnet u201d mri since this will prevent inaccuracies upon matching the coordination systems 0029 fig3 shows that this navigation device can also be directly connected to the instrument insertion channel 10 there could also be a navigation system for the device 2 a well as for the instrument insertion channel 10 resulting in having two navigation systems working with either different wavelengths or different codification or with different geometrically designed reflectors 12 the device can be manufactured of a material that is not depictable under mri or with other radiological imaging methods single parts or areas of the device could be designed of a material that is actively or passively identifiable under mri for instance the entire device for the operation under mri could be manufactured of plastics such as peek and only certain parts would be designed of titanium the device could also be designed to have hollow spaces containing a liquid which will emit active signals such as liquids with unpaired proton spin for instance a gadolinium based liquid fig1 shows a double.