Patent ID: 7850610

Claim:
A medical device localization system, comprising: a plurality of orthogonally-arranged electrode pairs defining orthogonal planes extending through a mapping volume within a patient; a measuring electrode; an ultrasound marking transducer located in close proximity to the measuring electrode; a calibration electrode spaced apart from the measuring electrode; a reference electrode spaced apart from the measuring electrode and the calibration electrode; a reference ultrasound marking transducer located in close proximity to the reference electrode; a location mapping unit adapted to define the mapping volume and to locate the measuring electrode within the mapping volume by measuring a voltage signal between the measuring electrode and the reference electrode in response to electrical signals applied to the plurality of orthogonally-arranged electrode pairs; an ultrasound unit adapted to generate an ultrasound image of the patient's anatomy within the mapping volume; and a display unit adapted to receive data from the location mapping unit and from the ultrasound unit and to superimpose the location of the measuring electrode onto the ultrasound image; wherein the relative location of a reference plane in the mapping volume with respect to the ultrasound image is established by aligning an initial ultrasound scanning plane with the reference plane in the mapping volume by adjusting the initial ultrasound scanning plane to include both of the ultrasound marking transducer and the reference ultrasound marking transducer, and wherein the display unit is configured to display the relative location of the reference plane with respect to an ultrasound scanning plane.