Aren’t all magnetic trackers the same?
A. No, there are several generations of trackers on the market. These range from 1st generation AC electromagnetic technology, first patented by Polhemus Inc. in the 1970s, and later enhanced by medical device companies, including Biosense, GE, Medtronic, MediGuide, NDI, and SuperDimension; 2nd generation trackers patented by Ascension in the 1990s that employ pulsed DC magnetic technology; and now 3rd generation DC magnetic technology, also patented by Ascension. 3D Guidance technology offers the latest improvements and innovations in magnetic tracking technology. First generation trackers are notoriously susceptible to distorted measurements in the presence of common metals, such as carbon steel, aluminum, and even stainless steel. Second generation DC trackers exhibit only 1/5 the sensitivity to non-magnetic conductive metal as their earlier counterparts. As a result their sensors can be attached to ultrasound scanheads, titanium instruments, and non-magnetic stainless steel objects
