Method and apparatus for mapping a structure

• US 8,663,120 B2
• Filed: 04/17/2009
• Issued: 03/04/2014
• Est. Priority Date: 04/18/2008
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc), Regents of The University of Minnesota (University of Minnesota)
• Original Assignee: Medtronic Incorporated (Medtronic Plc), Regents of The University of Minnesota (University of Minnesota)
• Inventors: Markowitz, H. Toby, Phillips, Lane A.
• Primary Examiner(s): Koharski, Christopher D
• Assistant Examiner(s): MAHMOOD, NADIA AHMAD
• Application Number:
  US12/425,480
• Publication Number:
  US 20090297001A1
• Time in Patent Office: 1,782 Days
• Field of Search: 607/60, 600/508
• US Class Current: 600/508
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61B 2017/00053 Mapping
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2034/105 Modelling of the patient, e.g. for ligaments or bones
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2053 Tracking an applied voltage gradient
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 2560/063 Devices specially adapted for delivering implantable medical measuring apparatus
• 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 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/0536 Impedance imaging, e.g. by tomography
• CPC Class Codes: A61B 5/0538 invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/063 using impedance measurements
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/29 for permanent or long-term implantation
• CPC Class Codes: A61B 6/503 for diagnosis of the heart
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 8/0891 for diagnosis of blood vessels
• CPC Class Codes: G06T 19/00 Manipulating 3D models or images for computer graphics

Abstract

An area of a patient can be mapped with a system operable to identify a plurality of locations and save a plurality of locations of a mapping instrument. The mapping instrument can include one or more electrodes that can sense a voltage that can be correlated to a three dimensional location of the electrode at the time of the sensing or measurement. Therefore, a map of an area or volume can be determined based upon the sensing of the plurality of points without the use of an imaging device. An implantable medical device can then be navigated relative to the mapping data.

Claims

1. A method of generating a map of a surface of a structure in an anatomy, comprising:

acquiring a first plurality of discrete position data points in a first region in the anatomy with a position element positioned within the first region;

rendering a first region display of a map based on the acquired first plurality of discrete position data points in a first region;

acquiring at least one second discrete position data point in the anatomy after acquiring the first plurality of discrete position data points with the position element positioned within the first region or a second region;

determining whether at least one acquired second discrete position data point is within the first region, wherein the second discrete position data point is acquired subsequent to the acquired first plurality of discrete position data points; and

if it is determined that the acquired at least one second discrete position data point is not in the first region, rendering a second region display of the map relative to the rendered first region display and only augmenting the rendered first region display of the map with the rendered second region display of the map based on the acquired at least one second discrete position data point.

2. The method of claim 1, further comprising:

positioning the position element in a volume to acquire both the first plurality of discrete position data points and at least one second discrete position data point at least in part by moving the position element within the volume; and

moving the position element within the volume to a plurality of positions to acquire both the first plurality of discrete position data points and at least one second discrete position data point;

wherein acquiring the discrete position data point includes determining the position of the position element at each of the positions of the position element.

3. The method of claim 2, further comprising:

placing a pair of axis patches on a surface of the volume;

injecting a current between the pair of axis patches to generate an axis of current in the volume; and

evaluating an electrical property using the position element to determine the position of the position element.

4. The method of claim 2, wherein acquiring the at least one of second discrete position data point includes acquiring the at least one second position data after the first plurality of position data;

wherein determining whether the second position data is within the first region includes determining that the second position data is outside a spatial boundary defined by the first region;

wherein the boundary defined by the first region includes a three-dimensional surface.

5. The method of claim 4, wherein rendering a first region display includes determining at least one of a three dimensional surface, a managed point in three-dimensional space, and a point in three dimensional space and rendering at least one of the three dimensional surface, a managed point in three-dimensional space, and a point in three dimensional space of the first region.

6. The method of claim 5, wherein rendering only a second region display relative to the rendered first region display includes augmenting the three dimensional surface of the first region display based only on the second position data without re-rendering the three dimensional surface of the first region.

7. The method of claim 1, wherein determining whether the second position data is within the first region includes determining whether the second position data spatially augments the first region, is spatially in addition to the first region, is a position substantially identical to at least one of the first plurality of position data, or combinations thereof.

8. The method of claim 7, wherein only rendering a second region display includes only rendering a display of the at least one of second discrete position data point when the second discrete position data point is not a part of the rendered first region display.

9. The method of claim 1, further comprising:

positioning at least three pairs of axes electrodes on a surface of a volume; and

injecting current between each of the three pairs of axes electrodes to generate three axes substantially orthogonal to one another;

wherein each of the first plurality of discrete position data points includes substantially three dimensional data;

wherein acquiring a second discrete position data point includes acquiring at least a three dimensional position data;

wherein rendering a first region display includes rendering a three dimensional region of the map.

10. The method of claim 9, wherein rendering the first region display includes point discretization, Gaussian voxelization, iso-surface extraction, and surface mesh data to render a surface on a display device;

wherein rendering only the second region display includes point discretization, Gaussian voxelization, iso-surface extraction and surface mesh data of only the second discrete position data point to render a surface only including the second discrete position data point;

wherein the surface of the second discrete position data point is rendered without altering the previously rendering first region display.

11. The method of claim 10, wherein three pairs of axes electrodes are positioned on at least one of a surface of an anatomical body and a surface of an organ with the anatomical body.

12. The method of claim 1, further comprising:

rending a complete map including the rendered first region display and a second rendered region based on the second position data;

wherein rendering the complete map includes;

retaining the rendered map of the first region; and

only rendering a portion of the complete map altered by the second discrete position data point based on point discretization, Gaussian voxelization, iso-surface extraction, and surface mesh data of the second discrete position data point only.

13. A method of rendering a map of an internal surface of a volume of an anatomy of a subject, comprising:

moving a position element within the volume to a plurality of discrete first positions;

moving the position element within the volume to a plurality of discrete second positions that are different than at least a sub-plurality of the plurality of discrete first positions within the volume after moving the position element within the volume to the plurality of discrete first positions; and

operating a processor system configured for;

determining first position data of the position element at each of the discrete first positions;

rendering a first map based on the determined first position data;

determining a second position data of the position element at each of the discrete second positions;

determining if any of the determined second position data are identical to the determined first position data, and if any of the determined second position data are not identical to the determined first position data, rendering for display a second map based only on the determined second position data; and

only augmenting the first rendered map with the second rendered map for display;

wherein the first position data and the second position data is acquired only with the position element.

14. The method of claim 13, wherein only augmenting the first rendered map includes:

retaining the first rendered map; and

rendering the second rendered map relative to the first rendered map to update the retained first rendered map without re-rendering the retained first rendered map.

15. The method of claim 13, wherein only augmenting the first rendered map with the second rendered map includes only incrementally changing the rendered portions of the first rendered map required to illustrate the second rendered map as a representation of the internal surface of the volume.

16. The method of claim 13, wherein rendering a first map includes at least point discretization, Gaussian voxelization, iso-surface extraction, and surface mesh data;

wherein only augmenting the first rendered map with the second rendered map includes point discretization, Gaussian voxelization, iso-surface extraction, and surface mesh data analysis of the determined plurality of second positions.

17. The method of claim 16, wherein rendering the second rendered map is performed without re-rendering the first rendered map.

18. The method of claim 13, wherein moving the position element to the plurality of discrete first positions includes moving the position element within a cardiovascular system of a human.

19. The method of claim 18, wherein rendering a first map includes rendering at least one of an internal surface of a superior of vena cava, right atrium, inferior vena cava, right ventricle, pulmonary artery, coronary sinus ostium, or combinations thereof.

20. The method of claim 19, further comprising:

positioning at least three pairs of axis electrodes on a surface of a human; and

injecting current between each of the pairs of axis electrodes to generate three substantially orthogonal axes within the volume of the human;

wherein determining the discrete first position data and determining the discrete second position data includes determining a position of the position element along each of the three axes injected into the human.

21. The method of claim 20, further comprising:

rendering a single surface for display based on the first map and the second map.

22. A system to render a map of an internal surface of a volume of an anatomy, comprising:

a position element operable to be moved in the volume to a first plurality of discrete positions within a first region of the volume and a second plurality of discrete positions within the volume that are different than the first plurality of discrete positions;

a position sensing system positioned relative to the volume, including a processor operable to;

determine the relative positions of the first plurality of positions and the relative positions of the second plurality of positions;

render a first map based on the determined position of the position element in each of the first plurality of positions; and

determine if the plurality of second discrete positions that are different than the first plurality of discrete positions are within the first region, and if the plurality of second discrete positions are not within the first region, render a second map based only on the determined second position data and only augmenting the first rendered map with the second rendered map, wherein only augmenting the first rendered map includes a complete addition of the second rendered map to the first rendered map or changing a boundary of the first rendered map with the second rendered map; and

a display device to display the rendered first map, rendered second map, the augmented first rendered map with the complete addition of the second rendered map, and combinations thereof.

23. The system of claim 22, wherein the position sensing system includes:

at least three pairs of axis electrodes; and

a driver operable to inject a current into the volume between each of the three pair of axis electrodes to generate three substantially orthogonal axes of current in the volume.

24. The system of claim 23, wherein the at least three pairs of axis electrodes are positionable on a surface of a human body;

wherein the axes of current intersect within the human body.

25. The system of claim 24, wherein the position element includes an electrode.

26. The system of claim 25, wherein the position element includes at least two electrodes spaced apart on a mapping instrument.

27. The system of claim 26, wherein the mapping instrument includes an inflatable portion positioned between and separate from the at least two spaced apart electrodes.

28. The system of claim 27, wherein the processor is operable to generate a single surface for display on the display device based on the first rendered map and the second rendered map.

29. A system to render a map of an internal surface of a volume of an anatomy, comprising:

a position element means for moving within the volume to a first plurality of positions within a first region of the volume and a second plurality of positions within the volume;

a position sensing means positioned relative to the volume, including a processor means for determining the relative positions of the first plurality of positions and the relative positions of the second plurality of positions;

a differentiation determination means for determining if the plurality of second positions are within the first region, if the plurality of second positions are not within the first region and different from the first plurality of positions, and determining if a second map should be rendered;

a rendering means for rendering a first map based on the determined position of the position element in each of the first plurality of positions and rendering a second map based only on the determined second position data and only augmenting the first rendered map with the second rendered map; and

a display means to display the rendered first map, rendered second map, the augmented first rendered map with the second rendered map, and combinations thereof.

30. The system of claim 29, further comprising:

a storage means for storing the first rendered map;

wherein the storage means retains the first rendered map for display with the display means while differentiation determination means is determining is a difference in first and second positions and the rendering means renders the second map based on the second position data.