×

Catheter tracking system

  • US 6,298,261 B1
  • Filed: 11/16/1998
  • Issued: 10/02/2001
  • Est. Priority Date: 11/15/1997
  • Status: Expired due to Term
First Claim
Patent Images

1. A catheter tracking system for locating and tracking a catheter head with reference to a part of the human or animal body, said catheter tracking system comprising:

  • a plurality of spaced apart transducers, at least one of which is disposed on a catheter and at least two others of which are disposed at predetermined reference points; and

    a signal processing unit coupled to the plurality of spaced apart transducers and arranged to selectively enable individual ones of said plurality of spaced apart transducers to operate as either a transmitter or a receiver, and to energize at least one of the transmitters to generate at least one transmitted signal which is detected by at least one of said receivers, a time of flight of the at least one transmitted signal generated by the at least one transmitter and received by the at least one receiver being indicative of a distance between said at least one transmitter and said at least one receiver, and times of flight between the at least one transducer disposed on the catheter and the at least two other transducers disposed at said predetermined reference points providing an indication of the location of the catheter with reference to said reference transducers;

    wherein, the at least one transmitted signal has a predetermined waveform;

    the signal processing unit compares the at least one transmitted signal generated by said at least one transmitter with a signal representative of the transmitted signal received by the at least one receiver, and determines the time of flight of the at least one transmitted signal based on a result of said comparison; and

    said comparison is performed using cross-correlation of pairs of transmitted and received signals, with the received signal being shifted in time, a maximum peak of energy resulting from the cross-correlation being detected, and the time of flight being determined from a time shift corresponding to a temporal position of maximum cross-correlation energy.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×