A registration artifact (10) for use in registering two or more
fluoroscopic images includes a plurality of radio opaque spheres (12, 14,
16) and a plurality of trackable markers, such as optical reflectors (20,
22, 24 and 26), mounted to a radio transparent body (11). A tracking
system locates the position of registrable artifact using the trackable
markers for registering the fluoroscopic images with respect to a known
frame of reference.