Patent ID: 7902816

Claim:
An electromagnetic tracking method featuring compensation of metal artifacts, comprising: providing an electromagnetic field generator ( 12 ) for generating an electromagnetic field ( 14 ) in a region of interest ( 16 ), wherein the electromagnetic field is subject to distortion in response to a presence of metal artifacts proximate the electromagnetic field and the region of interest; providing an array of reference sensors ( 30 , 50 , 102 , 104 , 110 ) disposed proximate the region of interest, the array of reference sensors having a predefined known configuration; determining a first set of locations of the array of reference sensors with respect to the electromagnetic field generator in response to an excitation of one or more of the reference sensors via the electromagnetic field; using a second mechanism ( 28 ), other than the electromagnetic field, for determining a first portion of a second set of locations of at least one or more reference sensor of the array of reference sensors with respect to the second mechanism, the second mechanism being in a known spatial relationship with the electromagnetic field generator; determining a remainder portion of the second set of locations of the reference sensors of the array of reference sensors in response to (i) the first portion of the second set of locations determined using the second mechanism and (ii) the predefined known configuration of the array of reference sensors; and compensating for metal distortion of the electromagnetic field in the region of interest as a function of the first and second sets of reference sensor locations of the array of reference sensors.