GLOBAL AND SEMI-GLOBAL REGISTRATION FOR IMAGE-BASED BRONCHOSCOPY GUIDANCE

• US 20120203065A1
• Filed: 01/31/2012
• Published: 08/09/2012
• Est. Priority Date: 02/04/2011
• Status: Active Grant

• Current Assignee: Penn State Research Foundation
• Original Assignee: Penn State Research Foundation
• Inventors: Higgins, William E., Khare, Rahul
• Granted Patent: US 9,757,021 B2
• Time in Patent Office: Days
• US Class Current: 600/109
• CPC Class Codes: A61B 1/2676 Bronchoscopes
• CPC Class Codes: A61B 2090/365 augmented reality, i.e. correlating a live optical image with another image
• 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 6/12 Arrangements for detecting or locating foreign bodies
• CPC Class Codes: A61B 6/5217 extracting a diagnostic or physiological parameter from medical diagnostic data
• CPC Class Codes: A61B 6/5247 combining images from an ionising-radiation diagnostic technique and a non-ionising radiation diagnostic technique, e.g. X-ray and ultrasound
• CPC Class Codes: A61B 6/583 using calibration phantoms
• CPC Class Codes: G06V 10/754 involving a deformation of the sample pattern or of the reference pattern; Elastic matching
• CPC Class Codes: G06V 10/98 Detection or correction of errors, e.g. by rescanning the pattern or by human intervention; Evaluation of the quality of the acquired patterns
• CPC Class Codes: G06V 20/647 by matching two-dimensional images to three-dimensional objects
• CPC Class Codes: G06V 20/653 by matching three-dimensional models, e.g. conformal mapping of Riemann surfaces
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

Two system-level bronchoscopy guidance solutions are presented. The first incorporates a global-registration algorithm to provide the physician with updated navigational and guidance information during bronchoscopy. The system can handle general navigation to a region of interest (ROI), as well as adverse events, and it requires minimal commands so that it can be directly controlled by the physician. The second solution visualizes the global picture of all the bifurcations and their relative orientations in advance and suggests the maneuvers needed by the bronchoscope to approach the ROI. Guided bronchoscopy results using human airway-tree phantoms demonstrate the potential of the two solutions.

Claims

1. In a system for image-guided bronchoscopy, wherein global and local algorithms are used to register real bronchoscopic (RB) endoluminal video frames obtained from a bronchoscope to virtual bronchoscopic (VB) views computed from a 3D MDCT chest scan, a method of recovering from an adverse event, comprising the steps of:

detecting a faulty bronchoscope maneuver caused by an adverse event; and

performing at least one step to re-register the RB endoluminal video frames and the VB views to ensure that the bronchoscope remains on a correct path to a region of interest (ROI).

2. The method of claim 1, including the step of holding the bronchoscope steady until the adverse event passes.

3. The method of claim 1, wherein the VB views and video frames include luminal bifurcations, and step to re-register includes moving the bronchoscope to a nearby bifurcation after the adverse event has passed so that the endoluminal video frames provide a complete view of the lumen region.

4. The method of claim 1, wherein the VB views and video frames include luminal bifurcations, and the method includes the step of invoking a global registration algorithm at every bifurcation to synchronize the positions of the real and virtual bronchoscopes.

5. The method of claim 1, including the step of invoking a local registration algorithm to synchronize the positions of the virtual and the real bronchoscopes in the vicinity of the ROI.

6. The method of claim 1, including the step of superimposing the ROI on an RB frame along with a graphical arrow to provide localized guidance to the ROI.

7. The method of claim 1, including the step of advancing the bronchoscope by one airway generation along the indicated path if it is determined that global registration is correct and the bronchoscope is on the correct path.

8. The method of claim 1, including the step of pulling back on the bronchoscope N generations, where N indicates the number of airway generations needed to pull the bronchoscope back onto the correct path, if it is determined that global registration is correct but that the bronchoscope is not on the correct path.

9. The method of claim 1, including the step of holding the bronchoscope steady and causing the virtual bronchoscope to return to its previous position if it is determined that global registeration is incorrect when invoking the global registration algorithm.

10. The method of claim 1, wherein, the adverse event is a cough or other event causing the bronchoscope to move to an unknown position within an airway tree.

11. The method of claim 1, wherein, the search space of the global registration algorithm includes branches lying within one or more airway generations associated with previously registered positions.

12. The method of claim 1, wherein, the search space of the global registration is limited to a specific lung.

13. The method of claim 1, wherein, the search space of the global registration is limited to a specific lobar region of the lung.

14. The method of claim 1, wherein, the search space of the global registration algorithm includes at least one user-defined parameter.

15. The method of claim 1, wherein, the search space of the global registration algorithm is tuned to detect faulty maneuvers by the bronchoscope.

16. The method of claim 1, wherein, in case of an adverse event, the search space for the global registration algorithm is tuned to re-establish the position of the bronchoscope in the airway tree.

17. The method of claim 1, wherein the VB views and video frames include luminal bifurcations, and bronchoscope movement directions are suggested to a user at each bifurcation.

18. The method of claim 1, including the step of instructing a user to pull back to a known, correct route in the case of a faulty bronchoscope maneuver.

19. A semi-global method for image-guided bronchoscopy, including the steps of:

presenting a global picture of all bifurcations and their relative proper orientations along a route to a region of interest (ROI) within an airway tree; and

providing guidance to a user of a bronchoscope to the ROI.

20. The method of claim 19, including the step of presenting two views for every bifurcation along the route to the ROI.

21. The method of claim 20, wherein one view depicts the bifurcation as seen by the bronchoscope when that bifurcation is approached by the bronchoscope.

22. The method of claim 20, wherein one view depicts the bifurcation as seen by the bronchoscope after the suggested discrete bronchoscope maneuver is carried out.

23. The method of claim 19, including the step of using an animated sequence to suggest a bronchoscope maneuver.

24. The method of claim 19, including the step of suggesting a standard bronchoscope maneuver such as a rotate-flex-advance maneuver at a bifurcation.

25. The method of claim 19, wherein a known limitation in the maneuverability of the bronchoscope is used to determine discrete bronchoscope maneuvers at a bifurcation.

26. The method of claim 25, wherein the known limitation in the maneuverability of the bronchoscope includes rotation.

27. The method of claim 19, including the step of determining discrete bronchoscope maneuvers to minimize the total rotation of the bronchoscope at a bifurcation.

28. The method of claim 19, wherein user preferences for bifurcation orientations are used to determine a discrete bronchoscope maneuver at a bifurcation.

29. The method of claim 19, wherein airway tree topology is used to determine a discrete bronchoscope maneuver at a bifurcation.

30. The method of claim 19, including the step of suggesting discrete bronchoscope rotation and articulation maneuvers at a bifurcation.

31. The method of claim 19, wherein branch length, orientation and airway tree topology are used to determine if bifurcations that can be skipped in conjunction with the step of presenting the global picture to guide a user.

32. The method of claim 31, including user-defined parameters to determine if a bifurcation may be skipped.