1. A surgical instrument navigation system, comprising: a surgical instrument; a tracking subsystem operable to capture in real-time position data indicative of the position of the surgical instrument; a data processor adapted to receive scan data representative of a region of interest of a given patient and the position data from the tracking subsystem, the data processor being operable to render an image of the region of interest from a point of view which relates to position of the surgical instrument, the image being derived from the scan data; and a display in data communication with the data processor, the display being operable to display the image of the patient.