Patent ID: 8456182
Filing Date: 2013-06-04
Classification: A61B

Abstract:
1. A method, comprising: positioning body-electrodes in galvanic contact with a body of a patient; positioning a mapping-tool, having a mapping-electrode, in a plurality of regions in the body of the patient; tracking the mapping-tool at different positions in each of the regions using a location-measuring system; for each region, generating a respective set of calibration-currents between the body-electrodes and the mapping-electrode at the different positions in the region; deriving for each region a respective relation between the respective set of the calibration-currents and the different positions, such that the different positions of the regions have different respective relations; positioning an investigation-tool having an investigation-electrode at a location in the body of the patient and generating investigation-tool-currents between the body-electrodes and the investigation-electrode at the location; and determining the location in response to the different respective relations and the investigation-tool-currents, wherein deriving the respective relation comprises one of: associating a volume including the different positions with the relation, wherein determining the location comprises verifying that the location is within the volume, and verifying that a number of the different positions exceeds a preset number of different positions prior to deriving the respective relation.