| 主权项 |
1. A method of catheterization, comprising the steps of:
creating a subject-specific skeletal model of a body of a subject; in the model defining an intended path of a probe within the body that leads from a point of insertion of the probe to a target; inserting the probe into the body, wherein the probe comprises at least one electrode; passing electrical currents through the body between the at least one electrode and respective electroconductive location pads that are disposed at a plurality of locations on a surface of the body, wherein the plurality of locations are distributed along the intended path of the probe, the location pads having operating volumes, the location pads being deliberately arranged so that the operating volumes of immediately neighboring pads overlap; measuring respective characteristics of the currents passing through the plurality of locations; and while inserting the probe iteratively determining position coordinates of the probe responsively to the measured characteristics; in the model tracking an actual path of the probe using the iteratively determined position coordinates; and determining whether the actual path corresponds to the intended path, wherein creating a subject-specific skeletal model comprises:
applying a hand-held probe to respective landmarks on the body, the hand-held probe comprising a magnetic sensor;applying a magnetic field to the magnetic sensor;receiving signals from the magnetic sensor responsively to the magnetic field;computing respective positions of the landmarks responsively to the signals; andincluding the positions of the landmarks as reference locations in the model, wherein at least one of the conductive pads is a multi-location pad having a plurality of location pad units, wherein all the location pads are connected to an enhanced active current location (ACL) system, wherein a respective set of calibration currents is generated between the at least one electrode and the catheter at different positions in a region of interest, wherein a respective relation is derived for each position between the respective set of the calibration currents and the different positions, and is used in determining the location of the probe in response to the different respective relations and probe currents wherein, during insertion of the probe, the ACL subsystem processes data derived from selected location pad units, wherein said selected location pad units are those whose operating volumes include or are proximate the current location of the distal end of the probe and wherein distant pad units are ignored, wherein accuracy of the ACL subsystem is enhanced by correlating impedance measurements taken from the multi-location pad with location information provided by the magnetic sensor, and wherein the ACL subsystem is calibrated to conform to the position as computed from data supplied by the magnetic sensor. |
