CORRECTION OF SHIFT AND DRIFT IN IMPEDANCE-BASED MEDICAL DEVICE NAVIGATION USING MEASURED IMPEDANCES AT EXTERNAL PATCH ELECTRODES

摘要

A system and method are provided for determining characteristics of a device electrode disposed on a medical device within a body. A plurality of measurement electrodes are coupled to an external surface of the body and establish transmission paths for current through the body. An electronic control unit (ECU) is configured to cause transmission of current between a pair of active electrodes selected from the measurement electrodes and thereby generate a voltage on the device electrode. The ECU receives impedance signals from a plurality of passive electrodes among the measurement electrodes other than the active electrodes. The ECU establishes a virtual reference electrode at a reference position within the body responsive to the impedance signals and computes a position of the device responsive to the voltage on the device electrode and the reference position of the reference electrode. The ECU may also compute impedances at the device and measurement electrodes.

主权项

1. A system for determining one or more characteristics of a device electrode disposed on a medical device within a body, comprising:
an electronic control unit configured to:
cause transmission of a current between a first pair of active electrodes, said first pair of active electrodes selected from among a plurality of measurements electrodes each coupled to an external surface of said body, to thereby generate a first voltage on said device electrode;receive impedance signals from a plurality of passive electrodes, each of said passive electrodes comprising one of said plurality of measurement electrodes other than one of said first pair of active electrodes, each of said impedance signals indicative of an impedance at one of said plurality of passive electrodes;establish a virtual reference electrode at a reference position within said body responsive to said impedance signals;generate a position value responsive to said first voltage on said device electrode and said reference position of said reference electrode; and,scale said position value using a scaling value computed in response to said impedance signals.