Surgical Segment Navigator - SSN++

Since 2001, at the University of Heidelberg, Germany, the SSN++ has been developed, a markerless-registration navigation system, based on a native (=markerless) CT or MRI. In this case, the patient registration is obtained on the operating table, using a surface scanner. The SSN++ corelates the surface scan data (gathered on the operating table) with the skin surface reconstruction from the dataset obtained preoperatively by CT or MRI. This principle complies with the terrain contour matching principle described for flying objects. The advantage of the new method is that the registration of the patient's position becomes a simple automated procedure; on the other hand, the radiation load for the patient is reduced, compared to the method using markers.