Cointegration filter for a catheter navigation system

• US 9,820,677 B2
• Filed: 01/03/2013
• Issued: 11/21/2017
• Est. Priority Date: 01/03/2013
• Status: Active Grant

• Current Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Original Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc. (Abbott Laboratories)
• Inventors: Olson, Eric S.
• Primary Examiner(s): KISH, JAMES M
• Application Number:
  US13/733,521
• Publication Number:
  US 20140187905A1
• Time in Patent Office: 1,783 Days
• Field of Search: None
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 18/02 by cooling, e.g. cryogenic techniques devices for cooling specific reflex points of the body within cell-life limits A61H39/06
• CPC Class Codes: A61B 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2053 Tracking an applied voltage gradient
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/0538 invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 5/063 using impedance measurements
• CPC Class Codes: A61B 5/066 Superposing sensor position on an image of the patient, e.g. obtained by ultrasound or x-ray imaging
• CPC Class Codes: A61B 5/068 using impedance sensors
• CPC Class Codes: A61B 5/72 Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: A61B 5/7425 Displaying combinations of multiple images regardless of image source, e.g. displaying a reference anatomical image with a live image geometric transforms for image registration G06T3/14; enhancement using image fusion G06T5/50; algorithms for registration of images G06T7/30
• CPC Class Codes: A61B 5/743 Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots
• CPC Class Codes: A61B 8/0883 for diagnosis of the heart
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61M 25/0105 Steering means as part of the catheter or advancing means; Markers for positioning systems for detection of markers A61B
• CPC Class Codes: A61M 25/09 Guide wires
• CPC Class Codes: A61M 5/142 Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/178 Syringes
• CPC Class Codes: A61N 7/022 : intracavitary

Abstract

A system and method for determining a position of a medical device within a body are provided. The system includes an electronic control unit that receives position signals from position sensors of a first type and a second type disposed on the device and applies a filter to each of the position signals to obtain filtered estimated positions for each sensor. The unit computes a spline connecting the position sensors of the first type responsive to the filtered estimated positions for the sensors and estimates a spline position for the sensor of the second type along the spline. The unit generates maps between the spline position and filtered and unfiltered estimated positions for the sensor of the second type and determines actual positions for the sensors of the first type responsive to the filtered estimated position for the sensors and a composite map of the two maps.

Claims

1. A system for determining a position of a medical device within a body, comprising:

an electronic control unit configured to;

receive a position signal from each of a plurality of position sensors of a first type disposed on the medical device and from at least one position sensor of a second type disposed on the medical device;

apply a filter to each of said position signals to obtain filtered estimated positions for each of said plurality of position sensors of said first type and said at least one position sensor of said second type;

compute a spline connecting said plurality of position sensors of said first type responsive to said filtered estimated positions for said plurality of positions sensors of said first type;

estimate a spline position for said at least one position sensor of said second type along said spline;

generate a first map between said spline position and said filtered estimated position of said at least one position sensor of said second type;

generate a second map between said spline position and an unfiltered estimated position of said at least one position sensor of said second type;

generate a composite map using said first and second maps;

determine an actual position for one of said plurality of position sensors of said first type using said composite map and said filtered estimated position for said one of said plurality of position sensors of said first type; and

a display communicatively coupled to the electronic control unit and configured and arranged to display the composite map overlaid with the actual position of said one of said plurality of position sensors of said first type.

2. The system of claim 1 wherein said first type of position sensor comprises an electrical position sensor.

3. The system of claim 2 wherein said second type of position sensor comprises a magnetic position sensor.

4. The system of claim 1 wherein said second type of position sensor comprises a magnetic position sensor.

5. The system of claim 1 wherein said first and second maps comprise vector offsets between said spline position and corresponding said filtered estimated position and said unfiltered estimated position of said at least one position sensor of said second type.

6. The system of claim 1 wherein said first and second maps comprise transformation matrices between said spline position and corresponding said filtered estimated position and said unfiltered estimated position of said at least one position sensor of said second type.

7. The system of claim 1 wherein said at least one position sensor of said second type comprises a plurality of position sensors of said second type and said first and second maps comprise transformation functions between said spline positions for said plurality of position sensors of said second type and corresponding ones of said filtered estimated positions and said unfiltered estimated positions of said plurality of position sensors of said second type.

8. The system of claim 7 wherein said transformation functions comprise thin plate spline transformation functions.

9. The system of claim 1, wherein the electronic control unit is further configured to generate the composite map by subtracting, adding, multiplying, or dividing the first and second maps, respectively.

10. A method for determining a position of a medical device within a body, comprising:

receiving a position signal from each of a plurality of position sensors of a first type disposed on the medical device and from at least one position sensor of a second type disposed on the medical device;

applying a filter to each of said position signals to obtain filtered estimated positions for each of said plurality of position sensors of said first type and said at least one position sensor of said second type;

computing a spline connecting said plurality of position sensors of said first type responsive to said filtered estimated positions for said plurality of positions sensors of said first type;

estimating a spline position for said at least one position sensor of said second type along said spline;

generating a first map between said spline position and said filtered estimated position of said at least one position sensor of said second type;

generating a second map between said spline position and an unfiltered estimated position of said at least one position sensor of said second type;

generating a composite map using said first and second maps;

determining an actual position for one of said plurality of position sensors of said first type using said composite map and said filtered estimated position for said one position sensor of said first type; and

a display communicatively coupled to the electronic control unit and configured and arranged to display the composite map overlaid with the actual position of said one of said plurality of position sensors of said first type.

11. The method of claim 10 wherein said first type of position sensor comprises an electrical position sensor.

12. The method of claim 11 wherein said second type of position sensor comprises a magnetic position sensor.

13. The method of claim 10 wherein said second type of position sensor comprises a magnetic position sensor.

14. The method of claim 10 wherein said first and second maps comprise vector offsets between said spline position and corresponding said filtered estimated position and said unfiltered estimated position of said at least one position sensor of said second type.

15. The method of claim 10 wherein said first and second maps comprise transformation matrices between said spline position and corresponding said filtered estimated position and said unfiltered estimated position of said at least one position sensor of said second type.

16. The method of claim 10 wherein said at least one position sensor of said second type comprises a plurality of position sensors of said second type and said first and second maps comprise transformation functions between said spline positions for said plurality of position sensors of said second type and corresponding ones of said filtered estimated positions and said unfiltered estimated positions of said plurality of position sensors of said second type.

17. The method of claim 16 wherein said transformation functions comprise thin plate spline transformation functions.

18. The method of claim 10, wherein generating the composite map comprises subtracting, adding, multiplying, or dividing the first and second maps, respectively.