Bone navigation system

• US 20020183610A1
• Filed: 07/18/2002
• Published: 12/05/2002
• Est. Priority Date: 10/07/1994
• Status: Active Grant

• Current Assignee: Surgical Navigation Technologies, Inc. (Medtronic Plc), Saint Louis University
• Original Assignee: Saint Louis University and Surgical Navigation Technologies Incorporated
• Inventors: Smith, Kurt R., Foley, Kevin T., Bucholz, Richard D.
• Granted Patent: US 6,978,166 B2
• Time in Patent Office: Days
• US Class Current: 600/407
• CPC Class Codes: A61B 2017/00022 Sensing or detecting at the treatment site
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 2034/2072 Reference field transducer attached to an instrument or patient
• CPC Class Codes: A61B 2090/363 Use of fiducial points
• CPC Class Codes: A61B 2090/364 Correlation of different images or relation of image positions in respect to the body
• CPC Class Codes: A61B 2090/376 using X-rays, e.g. fluoroscopy
• CPC Class Codes: A61B 2090/378 using ultrasound
• CPC Class Codes: A61B 2090/3925 ultrasonic
• CPC Class Codes: A61B 2090/3929 Active markers
• CPC Class Codes: A61B 2090/3945 Active visible markers, e.g. light emitting diodes
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 2090/3983 Reference marker arrangements for use with image guided surgery
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• 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 5/0064 Body surface scanning
• CPC Class Codes: A61B 5/0073 by tomography, i.e. reconstruction of 3D images from 2D projections A61B5/0066 takes precedence
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• 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 5/061 Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body A61B1/00158 takes precedence
• CPC Class Codes: A61B 5/062 : using magnetic field
• CPC Class Codes: A61B 5/1077 : Measuring of profiles
• CPC Class Codes: A61B 6/12 : Arrangements for detecting or locating foreign bodies
• CPC Class Codes: A61B 6/501 : for diagnosis of the head, e.g. neuroimaging or craniography
• CPC Class Codes: A61B 8/00 : Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• CPC Class Codes: A61B 8/5238 : for combining image data of patient, e.g. merging several images from different acquisition modes into one image for image registration algorithms G06T7/30
• CPC Class Codes: A61B 90/10 : for stereotaxic surgery, e.g. frame-based stereotaxis
• CPC Class Codes: A61B 90/14 : Fixators for body parts, e.g. skull clamps; Constructional details of fixators, e.g. pins
• CPC Class Codes: A61B 90/36 : Image-producing devices or illumination devices not otherwise provided for
• CPC Class Codes: A61B 90/39 : Markers, e.g. radio-opaque or breast lesions markers

Abstract

A system for use during a medical or surgical procedure on a body. The system generates a display representing the position of two or more body elements during the procedure based on a reference image data set generated by a scanner. The system produces a reference image of a body elements, discriminates the body elements in the images and creates an image data set representing the images of the body elements. The system produces a density image of the body element. The system modifies the image data set according to the density image of the body element during the procedure, generates a displaced image data set representing the position and geometry of the body element during the procedure, and compares the density image of the body element during the procedure to the reference image of the body element. The system also includes a display utilizing the displaced image data set generated by the processor to illustrate the position and geometry of the body element during the procedure. Methods relating to the system are also disclosed.

Claims

1. A system for use during a medical or surgical procedure on a body, said system generating a display representing the position and geometry of one or more body elements during the procedure based on one or more reference images, said system comprising:

first means for producing the reference image of the one or more body elements;

means for discriminating the one or more body elements in said reference image and creating an image data set representing a position and geometry of the reference image of the one or more body elements;

second means for producing, during the procedure, a density image of the one or more body elements;

a processor modifying the image data set according to the density image said processor generating a displaced image data set representing the position and geometry of the one or more body elements during the procedure; and

a display utilizing the displaced image data set illustrating the position and geometry of the one or more body elements during the procedure.

2. The system of claim 1 wherein said second producing means comprises a reference array for providing a reference and means for determining the position of one or more reference points of the body element to be displayed relative to the reference array.

3. The system of claim 2 wherein the second producing means is a radiographic device.

4. The system of claim 3 wherein the radiographic device is a fluoroscopic device comprising a fluoroscopic tube and a fluoroscopic plate.

5. The system of claim 4 wherein the fluoroscopic tube is fixed in relation to the fluoroscopic plate between which the body elements are located for producing the density image of the one or more body elements during the procedure and wherein the processor compares the density image of the one or more body elements during the procedure to the position of the one or more body elements as represented by the image data set.

6. The system of claim 4 wherein the fluoroscopic tube is fixed in relation to a fluoroscopic plate between which the body elements are located for producing the density image of the one or more body elements during the procedure and wherein the processor compares the density image of the one or more body elements during the procedure to the geometry of the one or more body elements as represented by the image data set.

7. The system of claim 4 wherein said fluoroscopic tube has sensors thereon in communication with the reference array and wherein the determining means is adapted to determine the position of the tube relative to the reference array whereby the position of the density image of the one or more body elements can be determined.

8. The system of claim 4 wherein said fluoroscopic plate has sensors thereon in communication with the reference array and wherein the determining means is adapted to determine the position of the plate relative to the reference array whereby the position of the density image of the one or more body elements can be determined.

9. The system of claim 4 wherein said reference array has sensors thereon in communication with the fluoroscopic device and wherein the determining means is adapted to determine the position of the fluoroscopic device relative to the reference array whereby the position of the density image of the one or more body elements can be determined.

10. The system of claim 1 wherein the second producing means is a radiographic device.

11. The system of claim 10 wherein the radiographic device is a fluoroscopic device comprising a fluoroscopic tube and a fluoroscopic plate.

12. The system of claim 11 wherein the fluoroscopic tube is fixed in relation to the fluoroscopic plate between which the body elements are located for producing the density image of the one or more body elements during the procedure and wherein the processor compares the density image of the one or more body elements during the procedure to the position of the one or more body elements as represented by the image data set.

13. The system of claim 11 wherein the fluoroscopic tube is fixed in relation to a fluoroscopic plate between which the body elements are located for producing the density image of the one or more body elements during the procedure and wherein the processor compares the density image of the one or more body elements during the procedure to the geometry of the one or more body elements as represented by the image data set.

14. The system of claim 11 wherein said fluoroscopic tube has sensors thereon in communication with the reference array and wherein the determining means is adapted to determine the position of the tube relative to the reference array whereby the position of the density image of the one or more body elements can be determined.

15. The system of claim 11 wherein said fluoroscopic plate has sensors thereon in communication with the reference array and wherein the determining means is adapted to determine the position of the plate relative to the reference array whereby the position of the density image of the one or more body elements can be determined.

16. The system of claim 1 wherein the processor modifies the image data set to generate the displaced data set using an iterative process such that a two-dimensional projection through the displaced image data set matches the one or more density images during the procedure.

18. The system of claim 17 wherein the reference system comprises one or more reference frames in communication with a reference array and wherein the one or more reference frames are configured to be fixed in relation to a separate body element and being correlatable to the position of the reference points for each separate body element.

19. The system of claim 18, wherein the radiographic device is equipped with sensors that are in communication with the one or more reference frames whereby the position of the sensors relative to the reference array during the procedure is determined, whereby the position of the radiographic device is determined and whereby the position of the one or more body elements during the procedure is determined.

20. The system of claim 19, wherein the processor translates each of the image data subsets from the position of the one or more body elements as indicated in the image data set to the position of the one or more body elements during the procedure so that the displaced image data set consists of the translated image data subsets.

21. The system of claim 18, wherein the position of the one or more reference frames is known in relation to one of the body elements, and the reference system determines the position of the one or more reference frames relative to the reference array so that the body may be moved during the procedure while the one or more body elements remain in fixed relation to each other and in known relation to the one or more reference frames so that the system can determine the position of the one or more body elements after movement without re-determining the relative position of each of the reference points of the one or more body elements.

22. The system of claim 17 wherein the reference system determines a position of a contour of the one or more body elements during the procedure as represented by the two-dimensional radiographic image and wherein the processor compares the position of the contour of the one or more body elements during the procedure to a position of a contour of the one or more body elements as represented by the image data subset.

24. The system of claim 23, wherein the fluoroscopic device determines a position of the two-dimensional radiographic image of the one or more body elements during the procedure, and wherein the processor compares the position of the two-dimensional radiographic image of the one or more body elements during the procedure to the position of the one or more body elements as represented by the image data subset.

25. The system of claim 23, wherein the fluoroscopic device determines a position of the two-dimensional radiographic image based on a density of the one or more body elements during the procedure, and wherein the processor compares the position of the two-dimensional radiographic image based on the density of the one or more body elements during the procedure to the position of the one or more body elements as represented by the image data subset.

26. The system of claim 23 wherein the fluoroscopic device determines a position of a contour of the one or more body elements during the procedure, and wherein the processor compares the position of the contour of the one or more body elements during the procedure to a position of a contour of the one or more body elements as represented by the image data subset.

27. The system of claim 23 wherein the radiographic device produces a two-dimensional radiographic image based on a density of the one or more body elements.

28. The system of claim 17 wherein the processor further creates a two-dimensional projection image of the body element that has been discriminated in the image data subset.

30. The system of claim 29 wherein the producing means comprises:

a reference array for providing a reference; and

means for determining the position of the one or more body elements to be displayed relative to the reference array.

31. The system of claim 29 wherein the producing means comprises a device for determining a position of the one or more body elements during the procedure and wherein the processor compares the position of the one or more body elements during the procedure as determined by the device to the position of the one or more body elements as represented by the image data subset.

32. The system of claim 31 wherein the producing means comprises a radiographic device for determining a position of the one or more body elements during the procedure and wherein the processor compares the position of the one or more body elements during the procedure as determined by the device to the position of the one or more body elements as represented by the image data subset, and the position of the one or more body elements may be determined.

33. The system of claim 31 wherein the producing means determines the position of the one or more body elements based on density and wherein the processor compares the density of the one or more body elements during the procedure as determined by the device to the position of the one or more body elements as represented by the image data subset, and the position of the one or more body elements during the procedure may be determined.

34. The system of claim 29 wherein the processor modifying the image data subset transforms the image data subset to represent the position and geometry of the one or more body elements during the procedure, and the displaced image data set consists of the transformed image data subset.

35. The system of claim 29 wherein the processor creates a two-dimensional projection image of the body element that has been discriminated in the image data subset.

37. The system of claim 36 wherein the determining system determines the contour based on density.

38. The system of claim 36 wherein the processor is programmed to compare the determined contour of the one or more body elements during the procedure to the contour of the one or more body elements as represented by the image data subset.

39. The system of claim 36 wherein the determining system comprises a radiographic device for determining the contour of the one or more body elements during the procedure and wherein the processor compares the contour of the one or more body elements during the procedure as determined by the radiographic device to the contour of the one or more body elements as represented by the image data subset.

40. The system of claim 36 wherein the modification of the image data subset is such that a contour as determined in a two-dimensional projection through the displaced image data set matches the contour of the images of the one or more body elements during the procedure.

41. The system of claim 36 wherein the processor modifies the image data subset of the one or more body elements such that a contour defined by a two-dimensional projection through the displaced image data set matches the contour of the images during the procedure of the one or more body elements as determined by the determining system.

42. The system of claim 36 wherein the processor further creates a two-dimensional projection of the body element that has been discriminated in the image data subset.

17. A system for displaying relative positions of the one or more body elements during a procedure on a body, the system comprising:

a processor for discriminating the one or more body elements of a reference image data set to create an image data subset defining a position and geometry the one or more body elements, the image data subset further having a plurality of data points correlatable to a plurality of reference points for the one or more body elements, the position of reference points of a particular body element relative to the data points for that particular body element being known;

a reference system for determining, during the procedure, the position of the reference points of the one or more body elements relative to the reference points of the other one or more body elements;

a radiographic device for producing a two-dimensional radiographic image of the one or more body elements during the procedure which includes the identification of reference points of the one or more body elements;

wherein the processor further digitizes the one or more radiographic images and generates a displaced image data set representing the position of the body elements during the procedure by modifying the image data subset using an iterative process such that a two-dimensional projection through the displaced image data set matches the one or more radiographic images; and

a display utilizing the displaced image data set to display the relative position of the one or more body elements during the procedure.

23. The system of 17, wherein the radiographic device is a fluoroscopic device comprising a fluoroscopic tube and a fluoroscopic plate between which the one or more body elements are located during the procedure.

29. A system for use during a medical or surgical procedure on a body, said system generating a display from a displaced image data set representing the position and geometry of the one or more body elements during the procedure based on reference images taken of the one or more body elements by a scanner, said system comprising:

means for creating an image data set from the reference image of one or more body elements;

means for substantially discriminating the one or more body elements of the image data set and creating an image data subset representing a position and geometry of the one or more body elements;

means for producing, during the procedure, images of the one or more body elements to be displayed;

a processor for modifying the image data subset of the one or more body elements to generate a diplaced image data set such that a two-dimensional projection through the displaced image data set matches the images during the procedure of the one or more body elements as produced by the producing means, wherein the displaced image data set represents the position and geometry of the one or more body elements during the procedure; and

a display utilizing the displaced image data set and illustrating the position and geometry of the one or more body elements during the procedure.

36. A system for use during a medical or surgical procedure on a body, the system generating a display from a displaced image data set representing an image of the one or more body elements during the procedure based on reference images taken by a scanner, the reference images having contours of one or more body elements, the system comprising:

a processor configured to substantially discriminate the contour of the one or more body elements of the reference image as represented by an image data set by creating an image data subset which represents the contours of the one or more body element;

a determining system configured to determine, during the procedure, contours of images of the one or more body elements to be displayed;

a processor programmed to modify the image data subset according to the determined contour for one or more body elements during the procedure, the processor generating a displaced image data set representing the contour of the one or more body elements during the procedure; and

a display utilizing the displaced image data set to illustrate the position and geometry of the one or more body elements during the procedure.

43. A method for use during a procedure, said method generating a display representing the position of body elements during the procedure based on a reference image data set, said method comprising the steps of:

creating a reference image of one or more body elements and a corresponding image data set;

discriminating the one or more body elements from the soft tissue in the image data set;

producing a two-dimensional image based on density of the one or more body elements during the procedure;

producing a displaced image data set by modifying the image data set such that a two-dimensional projection through the displaced image data set matches the two-dimensional image during the procedure; and

generating a display based on the displaced image data set illustrating the position of the one or more body elements during the procedure.

44. The method of claim 43, further comprising the step of simulating the generation of a two-dimensional image of the body elements by creating a two-dimensional projection of the one or more body elements that had been discriminated in the image data set.

45. The method of claim 43 wherein the step of producing a displaced data set includes modifying the image data set based on density.

46. The method of claim 43 further comprising the step of determining the position of the body elements during the procedure.

47. The method of claim 43 wherein the step of generating a display based on the displaced image data set further comprises the substep of illustrating the geometry of the one or more body elements during the procedure.

49. The method of claim 48 wherein the step of producing a density image further comprises the substep of determining the position of one or more reference points of the one or more body elements to be displayed relative to a reference array.

50. The method of claim 48 wherein the step of producing the density image further comprises the substep of determining the position of a fluoroscopic tube and a fluoroscopic plate relative to a reference array and thereby determining the position of the density image of the one or more body elements.

51. The method of claim 48 wherein a reference array has sensors thereon in communication with a fluoroscopic device and wherein the step of producing the density image further comprises the substep of determining a position of the device relative to the reference array whereby the position of the density image of the one or more body elements can be determined.

52. The method of claim 48, further comprising the step of comparing the density image of the one or more body elements during the procedure to the position of the one or more body elements as represented by the image data set.

53. The method of claim 48, further comprising the step of comparing the density image of the one or more body elements during the procedure to the geometry of the one or more body elements as represented by the image data set.

54. The method of claim 48, further comprising the step of comparing a contour of the density image of the one or more body elements during the procedure to a contour of the one or more body elements as represented by the image data set.

55. The method of claim 48, further comprising the steps of:

digitizing one or more density images;

generating a two-dimensional image by creating a two-dimensional projection of the one or more body elements that have been discriminated in the image data set; and

generating a displaced image data set representing the position of the one or more body elements during the procedure by modifying the image data set using an iterative process such that the two-dimensional image matches the one or more density images.

56. The method of claim 48, further comprising the step of creating a two-dimensional projection of the body element that has been discriminated in the image data set.

58. The system of claim 57, further comprising a medical instrument, wherein the reference system identifies, during the procedure, a position of medical instrument relative to at least one of the body elements, and the display illustrates the position of the medical instrument relative to the body elements based on the identified position of the medical instrument.

59. The system of claim 58, wherein the reference system determines an orientation of the medical instrument relative to the body elements and the display illustrates the orientation of the medical instrument relative to the body elements.

60. The system of claim 57, wherein the reference system comprises one or more reference frames in communication with a reference array and wherein each of the one or more reference frames is configured to be fixed in relation to a separate body element and is correlatable to the position of the reference points for each separate body element.

61. The system of claim 60, further comprising a localizer for determining a position of the reference points of each of the body elements relative to the reference array.

62. The system of claim 61, further comprising a registration probe in communication with the reference array, wherein the localizer determines a position of a tip of the registration probe relative to the reference array and a position of the reference points of each of the body elements can be determined by positioning the tip of the registration probe at each of the reference points.

63. The system of claim 60, wherein the position of the one or more reference frames is known in relation to one of the body elements, and the reference system determines a position of the one or more reference frames relative to the reference array so that the body may be moved during the procedure while the body elements remain in fixed relation to each other and in known relation to the one or more reference frames so that the system can determine a position of each of the body elements after movement without re-identifying the relative position of each of the reference points of each of the body elements.

64. The system of claim 57, wherein the processor discriminates the body elements of the image data set by creating an image data subset representing the position and geometry of each of the body elements.

65. The system of claim 64, wherein the processor translates each of the image data subsets from the position of the body elements as represented in the image data set to the position of the body elements during the procedure so that the displaced data set consists of the translated image data subsets.

66. The system of claim 57, wherein the device comprises an radiographic device.

67. The system of claim 66, wherein the radiographic device is a fluoroscopic device which determines a position of a projection of each of the body elements during the procedure, and wherein the processor compares the position of the projection of the each of the body elements during the procedure to the position of each of the body elements as represented in the image data set.

68. The system of claim 67, wherein the fluoroscopic device comprises a fluoroscopic tube in fixed relation to a fluoroscopic plate between which the body elements are located.

48. A method for use during a medical or surgical procedure on a body, said method generating a display representing the position and geometry of one or more body elements during the procedure based on reference images taken of the one or more body elements, said method comprising the steps of:

producing a reference image of the one or more body elements;

discriminating the one or more body elements in said reference images and creating an image data set representing the position and geometry of the one or more body elements;

producing, during the procedure, a density image of the one or more body elements to be displayed;

generating a displaced image data set representing the position and geometry of the one or more body elements during the procedure, by comparing the density image of the one or more body elements during the procedure to the image data set of the one or more body elements and modifying the image data set according to the density image of the one or more body elements during the procedure; and

displaying the displaced image data set thereby illustrating the position and geometry of the one or more body elements during the procedure.

57. A system for displaying relative positions of body elements during a procedure on a body, the system comprising:

a memory storing an image data set, the image data set representing a position and density of the body elements based on reference images of the body, and having a plurality of data points correlatable to a plurality of reference points for each of the body elements, the position of reference points of a particular body element relative to the data points for that particular body element being known;

a reference system for identifying, during the procedure, the position of the reference points of each of the body elements relative to the reference points of the other body elements, and wherein the reference system determines a density of each of the body elements during the procedure;

a processor comparing the density of each of the body elements during the procedure as determined by a device to a density of each of the body elements as represented by the image data set, and modifying the spatial relation of the data points of one body element relative to the data points of another body element according to the identified relative position of the reference points during the procedure as identified by the reference system to generate a displaced image data set representing the position of the body elements during the procedure; and

a display utilizing the displaced image data set to display the relative position of the body elements during the procedure.