Clinical tool for structure localization

• US 20050148850A1
• Filed: 11/12/2004
• Published: 07/07/2005
• Est. Priority Date: 11/13/2003
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Laske, Timothy G., Morissette, Josee, Baxter, Walton W. III, Lahm, Ryan P.
• Granted Patent: US 7,797,030 B2
• Time in Patent Office: Days
• US Class Current: 600/407
• 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 5/065 Determining position of the probe employing exclusively positioning means located on or in the probe, e.g. using position sensors arranged on the probe
• CPC Class Codes: A61B 5/7285 for synchronising or triggering a physiological measurement or image acquisition with a physiological event or waveform, e.g. an ECG signal A61B6/5205, A61B6/541, A61B8/5207, A61B8/543 take precedence

Abstract

A method for localizing an internal body structure during an image-guided procedure that includes obtaining a three dimensional image of a body portion containing a targeted structure and selected reference structures; determining a set of landmark point coordinates for defining the location of each of the targeted and reference structures; computing triangulation parameters relating the location of the landmark points for the targeted structure and the reference structures; and, during an image-guided procedure, using the computed triangulation parameters to plot an estimated location of the targeted structure on an intra-operative image in which the reference structures have been identified.

Claims

1. A method, comprising:

generating a three dimensional image of a body portion including a targeted structure for a surgical procedure;

selecting reference structures located in the generated three dimensional image;

calculating landmark point coordinates for defining locations of each of the targeted structure and the reference structures to generate respective targeted structure landmark point coordinates and reference structures landmark point coordinates;

computing triangulation parameters relating the location of the targeted structure landmark point coordinates to the reference structures landmark point coordinates;

acquiring an intra-operative three dimensional image during the surgical procedure;

identifying locations of the reference structures in the intra-operative image; and

plotting a location of the targeted structure on the intra-operative image in response to the computed triangulation parameters and the identified locations of the reference structures in the intra-operative image.

2. The method of claim 1, wherein calculating the landmark point coordinates comprises:

generating separate oblique planes through each of the targeted reference structure and the selected reference structures;

selecting a plurality of points corresponding to one of the targeted structure and the reference structure in each of the respective oblique planes; and

calculating the landmark point coordinates in response to the selected plurality of points.

3. The method of claim 2, wherein the selected plurality of points corresponding to one of the targeted structure and the reference structures in each of the respective oblique planes are structure boundary points.

4. The method of claim 2, wherein the selected plurality of points corresponding to one of the targeted structure and the reference structures in each of the respective oblique planes are selected automatically based on a gray-scale or color-scale change in a digitized image.

5. The method of claim 2, wherein the selected plurality of points corresponding to one of the targeted structure and the reference structures in each of the respective oblique planes are selected manually using a pointing tool.

6. The method of claim 2, wherein one of the targeted structure landmark point coordinates and the reference structures landmark point coordinates are the coordinates of a centroid calculated from the selected plurality of points.

7. The method of claim 1, wherein the computed triangulation parameters include a distance ratio and an angle, wherein the distance ratio relates the lengths of two sides of a triangle formed by the targeted structure landmark point coordinates and two landmark point coordinates of the reference structures landmark point coordinates and the angle is the angle formed between the two sides of the triangle.

8. The method of claim 7, wherein computing triangulation parameters comprises computing triangulation parameters corresponding to each of two or more triangles, the two or more triangles being formed by the targeted structure landmark point coordinates and two of the reference structure landmark point coordinates.

9. The method of claim 8, wherein plotting the location of a targeted structure in an intra-operative image comprises:

generating a first circle defined by rotating a trajectory extending from a first identified reference structure at a corresponding computed angle relative to a line segment defined by the first identified reference structure and a second identified reference structure, the circumference of the circle being a distance from the first identified reference structure, wherein the distance is determined from the corresponding computed distance ratio and a distance measured in the intra-operative image between the first identified reference structure and the second reference structure;

generating a second circle by rotating a trajectory extending from a third identified reference structure at a corresponding computed angle relative to a line segment defined by the third identified reference structure and the second identified reference structure, the circumference of the circle being a distance from the third identified reference structure determined from the corresponding computed distance ratio and a distance measured in the intra-operative image between the third identified reference structure and the second identified reference structure; and

plotting the location of the targeted structure at an intersection of the first circle and the second circle.

10. The method of claim 1, wherein the reference structures include the superior vena cava ostium and the tricuspid valve.

11. The method of claim 1, wherein the targeted structure is the coronary sinus ostium.

12. The method of claim 1, wherein the targeted structure is a cardiac vein.

13. The method of claim 1, wherein the targeted structure is a targeted pacing site.

14. The method of claim 1, further including using electrophysiological mapping for locating a targeted structure or selected reference structures.

15. A method, comprising:

generating a three dimensional image of a body portion including a targeted structure for a surgical procedure;

selecting reference structures included in the image;

calculating landmark point coordinates for defining the locations of each of the targeted structure and the reference structures to generate respective targeted structure landmark point coordinates and reference structures landmark point coordinates;

defining an isocenter axis location in the patient'"'"'s body about which a two-dimensional imaging plane is rotated;

rotating the targeted structure landmark point coordinates and the reference structures landmark point coordinates about the isocenter axis to a selected planar imaging view;

calculating the targeted structure landmark point coordinates and the reference structures landmark point coordinates projected onto the selected planar view;

computing triangulation parameters relating the location of the projected targeted structure landmark point coordinates to the projected reference structures landmark point coordinates;

acquiring an intra-operative two-dimensional image during the surgical procedure;

identifying the locations of the selected reference structures in the intra-operative image; and

plotting a location of the targeted structure on the intra-operative image in response to the computed triangulation parameters and the identified locations of the reference structures in the intra-operative image.

16. The method of claim 15, wherein calculating the landmark point coordinates comprises:

generating separate oblique planes through each of the targeted structure landmark point coordinates and selected reference structures;

selecting a plurality of points corresponding to one of the targeted structure and the reference structure in each of the respective oblique planes; and

calculating the landmark point coordinates in response to the plurality of selected points.

17. The method of claim 16, wherein selected plurality of points corresponding to one of the targeted structure and the reference structures in each of the respective oblique planes are structure boundary points.

18. The method of claim 16, wherein the selected plurality of points corresponding to one of the targeted structure and the reference structures in each of the respective oblique planes are selected automatically based on a gray-scale or color-scale change in a digitized image.

19. The method of claim 16, wherein the selected plurality of points corresponding to one of the targeted structure and the reference structures in each of the respective oblique planes are selected manually using a pointing tool.

20. The method of claim 16, wherein the targeted structure landmark point coordinates and the reference structures landmark point coordinates are the coordinates of a centroid calculated from the selected plurality of points.

21. The method of claim 15, wherein the computed triangulation parameters include a distance ratio and an angle, wherein the distance ratio relates the lengths of two sides of a triangle formed by the targeted structure landmark point coordinates and two reference structure landmark points of the reference structures landmark point coordinates and the angle is the angle formed between the two sides of the triangle.

22. The method of claim 21, wherein plotting the location of a targeted structure in an intra-operative image comprises:

measuring the distance between two identified reference structures;

extending a trajectory from a first identified reference structure at a corresponding computed angle relative to a line segment defined by the first identified reference structure and a second identified reference structure; and

plotting the targeted structure at a location on the trajectory a distance from the first identified reference structure, wherein the distance is determined in response to the corresponding computed distance ratio and a distance measured in the intra-operative image between the first identified reference structure and the second identified reference structure.

23. The method of claim 15, wherein the first identified reference structure and the second identified reference structure include the superior vena cava ostium and the tricuspid valve.

24. The method of claim 15, wherein the targeted structure is the coronary sinus ostium.

25. The method of claim 15, wherein the targeted structure is a cardiac vein.

26. The method of claim 15, wherein the targeted structure is a targeted pacing site.

27. The method of claim 15, further comprising locating one of the targeted structure and the reference structures using electrophysiological mapping.

28. A method, comprising:

generating a three dimensional image of a body portion including a targeted structure for a surgical procedure;

selecting reference structures located in the three dimensional image;

calculating landmark point coordinates for defining the location of each of the targeted structure and the reference structures;

computing triangulation parameters relating the location of the landmark point coordinates of the targeted structure to the landmark point coordinates of the reference structures;

repeating generating of a three dimensional image, selecting reference structures, calculating landmark point coordinates, and computing triangulation parameters in a number of subjects; and

calculating triangulation parameters representative of the number of subjects based on the computed triangulation parameters.

29. The method of claim 28, further comprising:

acquiring an intra-operative image during the surgical procedure;

identifying the locations of the reference structures in the intra-operative image; and

plotting the location of the targeted structure on the intra-operative image in response to the triangulation parameters and the identified locations of the reference structures in the intra-operative image.

30. A method, comprising:

generating a three dimensional image of a body portion including a targeted structure for a surgical procedure;

selecting a reference structure included in the image;

calculating a set of landmark point coordinates for defining the locations of the targeted structure and reference structure;

defining an isocenter axis location in the patient'"'"'s body about which a two-dimensional imaging plane is rotated;

rotating the landmark coordinate points about the isocenter axis to a selected planar imaging view;

calculating the landmark point coordinates projected onto the selected planar view;

measuring the distance between the projected targeted structure landmark point and the projected reference structure landmark point;

measuring an angle between a local coordinate axis and a trajectory extending from the projected reference structure landmark point in the direction of the projected targeted structure landmark point;

acquiring an intra-operative two-dimensional image during the surgical procedure;

identifying the location of the reference structure in the intra-operative image; and

plotting the location of the targeted structure on the intra-operative image wherein the plotted location is based on the measured distance, measured angle, and the identified location of the reference structure in the intra-operative image.

31. An image guided surgery system, comprising:

means for computing triangulation parameters relating a targeted structure location to locations of selected reference structures; and

means for plotting an estimated location of the targeted structure on a medical image acquired intra-operatively in response to the computed triangulation parameters.

32. A computer-readable medium containing a set of instructions which, when implemented in a medical imaging system cause the system to:

compute triangulation parameters relating a location of a selected targeted structure to locations of selected reference structures; and

plot the location of the selected targeted structure on an intra-operative image in response to the computed triangulation parameters and identified locations of the selected reference structures in the intra-operative image.