A system and method for tracking or otherwise determining positioning of
an intracorporeal device is provided. The invention includes a device
that may be inserted into a subject and tracked based on an imageable tag
included with the device. The imageable tag is at least partially formed
of a substance whose nuclei precess at a Larmor frequency different than
the Larmor frequency of hydrogen when subjected to a polarizing magnetic
field. MR data may be acquired from the imageable tag using an RF
receiver tuned to the Larmor frequency of the substance and used to track
movement of the device within the subject.