Medical navigation apparatus

• US 7,174,202 B2
• Filed: 12/17/2002
• Issued: 02/06/2007
• Est. Priority Date: 08/14/1992
• Status: Expired due to Term

• Current Assignee: British Telecommunications (BT Group Plc) (BT Group PLC)
• Original Assignee: British Telecommunications (BT Group Plc) (BT Group PLC)
• Inventors: Bladen, John Stuart, Anderson, Alan Patrick
• Primary Examiner(s): Smith; Ruth S.
• Application Number:
  US10/320,658
• Publication Number:
  US 20030163037A1
• Time in Patent Office: 1,512 Days
• Field of Search: 600/407, 600/424, 600/117, 600/427, 128/899, 324/207.17, 324/207.26, 324/247, 702/152, 702/153
• US Class Current: 600/424
• CPC Class Codes: A61B 2017/00207 with hand gesture control or hand gesture recognition
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2034/742 Joysticks
• 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 5/06 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 5/064 using markers A61B5/062 takes precedence
• CPC Class Codes: A61B 5/6806 Gloves
• CPC Class Codes: G01B 7/004 for measuring coordinates of points
• CPC Class Codes: G01V 3/08 operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices with electromagnetic waves G01V3/12
• CPC Class Codes: H01F 2005/027 wound on formers for receiving several coils with perpendicular winding axes, e.g. for antennae or inductive power transfer

Abstract

Methods and apparatus are provided for locating the position, preferably in three dimensions, of a sensor by generating magnetic fields which are detected at the sensor. The magnetic fields are generated from a plurality of locations and, in one embodiment of the invention, enable both the orientation and location of a single coil sensor to be determined. The present invention thus finds application in many areas where the use of prior art sensors comprising two or more mutually perpendicular coils is inappropriate.

Claims

1. A medical navigation apparatus for navigating an anatomical body during a medical procedure, the medical navigation apparatus comprising:

a medical instrument operable to be navigated through the anatomical body during the medical procedure;

at least one field sensor associated with the medical instrument and operable to be moved in association with the medical instrument;

at least one magnetic field source operable to radiate at least one magnetic field into the anatomical body and operable to be detected by the at least one field sensor;

a controller operable to receive from the at least one field sensor signals indicative of the at least one magnetic field and operable to continuously ascertain positions of the at least one field sensor based upon the at least one magnetic field detected by the at one least field sensor; and

a display operable to continuously display representations of the position of the at least one field sensor associated with the medical instrument as it moves from a first position to a second position to form continuous representations, wherein the continuous representations include a representation of the first position, a representation of the second position, and representations of the positions between the first position and the second position

wherein the continuous representations of the position of the at least one field sensor is operable to be rotated in any direction on the display to illustrate the continuous representations from a plurality of perspectives of the continuous representations.

2. The medical navigation apparatus as defined in claim 1 wherein the medical instrument is a catheter.

3. The medical navigation apparatus as defined in claim 1 wherein the medical instrument is an endoscope.

4. The medical navigation apparatus as defined in claim 1 wherein the medical instrument is a colonoscope.

5. The medical navigation apparatus defined in claim 1 wherein the medical instrument is used for a cardiac medical procedure.

6. The medical navigation apparatus as defined in claim 1 wherein the at least one field sensor includes a single sensing coil.

7. The medical navigation apparatus as defined in claim 6 wherein the single sensing coil is an air-core coil.

8. The medical navigation apparatus as defined in claim 6 wherein the single sensing coil includes a magnetic permeable core.

9. The medical navigation apparatus as defined in claim 1 wherein the at least one field sensor is a flux gate magnetometer.

10. The medical navigation apparatus as defined in claim 1 wherein the at least one field sensor includes three sensing coils oriented orthogonal to one another about a common origin.

11. The medical navigation apparatus as defined in claim 1 wherein the at least one magnetic field is a quasi-static magnetic field.

12. The medical navigation apparatus as defined in claim 1 wherein the medical procedure is selected from a group comprising a colonoscopy, a bronchoscopy, a gastroscopy, a nasogastric procedure, an endotracheal procedure, cardiovascular procedure, and a combination thereof.

13. The medical navigation apparatus as defined in claim 1 wherein the at least one magnetic field source includes a first magnetic field source operable to generate a first magnetic field, a second magnetic field source operable to generate a second magnetic field and a third magnetic field source operable to generate a third magnetic field.

14. The medical navigation apparatus as defined in claim 13 wherein the first, second, and third magnetic field sources are positioned at known locations in a two-dimensional plane.

15. The medical navigation apparatus as defined in claim 14 wherein the first, second, and third magnetic field sources each include three coils oriented orthogonal to one another about a common origin.

16. The medical navigation apparatus as defined in claim 13 wherein the first, second, and third magnetic fields are sequentially generated in a time multiplexed manner.

17. The medical navigation apparatus as defined in claim 13 wherein the first, second, and third magnetic fields are generated in a frequency division multiplexed manner.

18. The medical navigation apparatus as defined in claim 13 wherein the first, second, and third magnetic field sources have a same center location.

19. The medical navigation apparatus as defined in claim 13 wherein the first, second, and third magnetic field sources each have a unique center location different from the center location of the other two field sources.

20. The medical navigation apparatus as defined in claim 1 wherein the at least one magnetic field source includes one field coil.

21. The medical navigation apparatus as defined in claim 1 wherein the at least one magnetic field source includes three field coils oriented orthogonal to one another about a common origin.

22. The medical navigation apparatus as defined in claim 1 wherein the ascertained positions include both the location and orientation of the at least one field sensor associated with the medical instrument.

23. The medical navigation apparatus as defined in claim 1 wherein the display is further operable to simultaneously display local information corresponding to an area in the anatomical body where the at least one field sensor is located while displaying the representation of the ascertained position of the at least one field sensor.

24. The medical navigation apparatus as defined in claim 23 wherein the local information is an image.

25. The medical navigation apparatus as defined in claim 1 wherein the at least one magnetic field is a near-field electromagnetic field.

26. The medical navigation apparatus as defined in claim 1 wherein the controller is operable to calculate from the signals a location, an elevation angle and a rotation angle of the at least one field sensor.

27. The medical navigation apparatus as defined in claim 1 wherein continuously displaying representations further includes displaying a three-dimensional map formed based on the representations.

28. The medical navigation apparatus as defined in claim 27 wherein contours of the anatomical body are displayed as a three-dimensional map.

29. The medical navigation apparatus as defined in claim 27 wherein the display is operable to simultaneously display an actual image of an internal structure of the anatomical body with the three-dimensional map.

30. The medical navigation apparatus as defined in claim 1 wherein the at least one field sensor is attached to the medical instrument and moves with the medical instrument.

31. The medical navigation apparatus as defined in claim 1 wherein the at least one field sensor moves independent of the medical instrument.

32. The medical navigation apparatus as defined in claim 1 wherein the at least one field sensor includes a plurality of field sensors associated with the medical instrument.

33. The medical navigation apparatus as defined in claim 1 wherein the ascertained positions of the at least one field sensor are three-dimensional positions of the at least one field sensor.

34. The medical navigation apparatus as defined in claim 33 wherein the display is operable to display the three-dimensional ascertained positions of the at least one field sensor using color coding.

35. The medical navigation apparatus as defined in claim 1 wherein the medical instrument is a catheter and the at least one field sensor is encapsulated within the catheter.

36. The medical navigation apparatus as defined in claim 1 further comprising an X-ray imaging device operable to generate an X-ray image of the anatomical body where the medical instrument is being navigated.

37. The medical navigation apparatus as defined in claim 36 wherein the X-ray image obtained from the X-ray imaging device is correlated with the display representations of the position of the at least one field sensor associated with the medical instrument.

38. The medical navigation apparatus of claim 1, wherein the continuous representation from a plurality of perspectives includes a display operable to display the continuous representation from a plurality of perspectives to determine three-dimensional spacing between different portions of the continuous representations of the positions.

39. A medical navigation apparatus for navigating an anatomical body during a medical procedure, the medical navigation apparatus comprising:

a medical instrument operable to be navigated through the anatomical body during a medical procedure;

at least one magnetic field source associated with the medical instrument and operable to be moved in association with the medical instrument, the at least one magnetic field source further operable to radiate at least one magnetic field out of the anatomical body;

at least one field sensor operable to detect the at least one magnetic field from the at least one magnetic field source;

a controller operable to receive from the at least one field sensor signals indicative of the at least one magnetic field and operable to continuously ascertain positions of the at least one field source based upon the at least one magnetic field detected by the at least one field sensor; and

a display operable to continuously display representations of the position of the at least one field source associated with the medical instrument as it moves from a first position to a second position, wherein the continuous representations include a representation of the first position, a representation of the second position, and representations of the positions between the first position and the second position;

wherein the display is operable to display the three-dimensional ascertained positions of the at least one field source where at least a first color and a second color are used to define the continuous representations to indicate a relative position of a portion of the continuous representations to a point.

40. The medical navigation apparatus as defined in claim 39 wherein the medical instrument is selected from a group comprising a catheter, an endoscope, a colonoscope, and a combination thereof.

41. The medical navigation apparatus defined in claim 39 wherein the medical instrument is used for a cardiac medical procedure.

42. The medical navigation apparatus as defined in claim 39 wherein the at least one field sensor includes a single sensing coil.

43. The medical navigation apparatus as defined in claim 39 wherein the at least one field sensor is a flux gate magnetometer.

44. The medical navigation apparatus as defined in claim 39 wherein the at least one field sensor includes three sensing coils oriented orthogonal to one another about a common origin.

45. The medical navigation apparatus as defined in claim 39 wherein the at least one magnetic field is a quasi-static magnetic field.

46. The medical navigation apparatus as defined in claim 39 wherein the medical procedure is selected from a group comprising a colonoscopy, a bronchoscopy, a gastroscopy, a nasogastric procedure, an endotracheal procedure, cardiovascular procedure, and a combination thereof.

47. The medical navigation apparatus as defined in claim 39 wherein the at least one magnetic field source includes one field coil.

48. The medical navigation apparatus as defined in claim 39 wherein the at least one magnetic field source includes three field coils oriented orthogonal to one another about a common origin.

49. The medical navigation apparatus as defined in claim 39 wherein the display is further operable to simultaneously display local information corresponding to an area in the anatomical body where the at least one field source is located while displaying the representation of the ascertained position of the at least one field source.

50. The medical navigation apparatus as defined in claim 49 wherein the local information is an image.

51. The medical navigation apparatus as defined in claim 39 wherein the at least one magnetic field is a near-field electromagnetic field.

52. The medical navigation apparatus as defined in claim 39 wherein the controller is operable to calculate from the signals a location, an elevation angle and a rotation angle of the at least one field source.

53. The medical navigation apparatus as defined in claim 39 wherein continuously displaying representations further includes displaying a three-dimensional map formed based on the representations.

54. The medical navigation apparatus as defined in claim 53 wherein contours of the anatomical body are displayed as a three-dimensional map.

55. The medical navigation apparatus as defined in claim 53 wherein the display is operable to simultaneously display an actual image of an internal structure of the anatomical body with the three-dimensional map.

56. The medical navigation apparatus as defined in claim 39 wherein the at least one field source is attached to the medical instrument and moves with the medical instrument.

57. The medical navigation apparatus as defined in claim 39 wherein the at least one field source moves independent of the medical instrument.

58. The medical navigation apparatus as defined in claim 39 wherein the ascertained positions of the at least one field source are three-dimensional positions of the at least one field source.

59. The medical navigation apparatus as defined in claim 39 wherein the medical instrument is a catheter and the at least one field source is encapsulated within the catheter.

60. The medical navigation apparatus as defined in claim 39 wherein the representations of the position of the at least one field source may be rotated in any direction on the display.

61. The medical navigation apparatus as defined in claim 60 wherein the x-ray image obtained form the x-ray imaging device is correlated with the displayed representations of the position of the at least one field source associated with the medical instrument.

62. The medical navigation apparatus as defined in claim 39 further comprising an x-ray imaging device operable to generate an x-ray image of the anatomical body where the medical instrument is being navigated.

63. A medical navigation apparatus for navigating in an anatomical body during a medical procedure, the medical navigation apparatus comprising:

a medical instrument operable to be navigated through the anatomical body during the medical procedure;

at least one field sensor associated with the medical instrument and operable to be moved in association with the medical instrument;

at least three magnetic field sources operable to radiate at least three magnetic fields into the anatomical body, where each magnetic field has a moment different from each moment of each of the other two magnetic fields relative to a fixed point in space, each magnetic field operable to be detected by the at least one field sensor;

a controller operable to receive from the at least one field sensor signals indicative of the at least three magnetic fields and operable to ascertain a position of the at least one sensor based upon the at least three magnetic fields detected by the at least one field sensor; and

a display operable to simultaneously display a representation of the ascertained position of the at least one field sensor and local information corresponding to an area in the anatomical body where the at least one field sensor is located;

wherein the representation of the ascertained position of the at least one field sensor includes at least a first color and a second color to distinguish positions of two portions of the representations relative to a point.

64. The medical navigation apparatus as defined in claim 63 wherein the local information is an image.

65. The medical navigation apparatus as defined in claim 63 wherein the at least one field sensor is a single coil sensor.

66. The medical navigation apparatus as defined in claim 63 wherein the displayed representation reflects the ascertained position in three-dimensions.

67. The medical navigation apparatus as defined in claim 63 wherein the medical instrument is selected from a group comprising a catheter, an endoscope, a colonoscope, and a combination thereof.

68. The medical navigation apparatus as defined in claim 63 wherein at least one field sensor is a flux gate magnetometer.

69. The medical navigation apparatus as defined in claim 63 wherein the at least one field sensor includes three sensing coils that are orthogonal to one another about a common origin.

70. The medical navigation apparatus as defined in claim 63 wherein at least one magnetic field is a quasi-static magnetic field.

71. The medical navigation apparatus as defined in claim 63 wherein the medical procedure is selected from a group comprising a colonoscopy, a bronchoscopy, a gastroscopy, a nasogastric procedure, an endotracheal procedure, cardiovascular procedure, and a combination thereof.

72. The medical navigation apparatus as defined in claim 63 wherein the at least three magnetic field sources each include at least two coils formed orthogonally to one another about a common origin and are positioned at known locations in a two-dimensional plane.

73. The medical navigation apparatus as defined in claim 63 wherein the ascertained positions include both the location and orientation of the at least one field sensor associated with the medical instrument.

74. The medical navigation apparatus as defined in claim 63 wherein the controller is further operable to continuously ascertain positions of the at least one field sensor based upon the at least three magnetic fields detected by the at least one field sensor;

and

the display is further operable to continuously display representations of the position of the at least one field sensor associated with the medical instrument as it moves from a first position to a second position, wherein the continuous representations include a representation of the first position, a representation of the second position, and representations of the positions between the first position and the second position.

75. The medical navigation apparatus as defined in claim 63 wherein contours of the anatomical body are displayed as a three-dimensional map.

76. The medical navigation apparatus as defined in claim 63 wherein the display is operable to simultaneously display an actual image of an internal structure of the anatomical body with the three-dimensional map.

77. The medical navigation apparatus as defined in claim 63 wherein the at least one field sensor moves independent of the medical instrument.

78. The medical navigation apparatus as defined in claim 63 wherein the at least one field sensor is attached to the medical instrument and moves with the medical instrument.

79. The medical navigation apparatus as defined in claim 63 wherein the at least one field sensor includes a plurality of field sensors associated with the medical instrument.

80. The medical navigation apparatus as defined in claim 63 wherein the ascertained position of the at least one field sensor are three-dimensional positions of the at least one field sensor.

81. The medical navigation apparatus as defined in claim 80 wherein the display is operable to display the three-dimensional ascertained positions of the at least one field sensor using color coding.

82. The medical navigation apparatus as defined in claim 63 further comprising an x-ray imaging device operable to generate an x-ray image of the anatomical body where the medical instrument is being navigated.

83. The medical navigation apparatus as defined in claim 82 wherein the x-ray image obtained from the x-ray imaging device is correlated with the display representation of the position of the at least one field sensor associated with the medical instrument.

84. A medical navigation apparatus for navigating an anatomical body during a medical procedure, the medical navigation apparatus comprising:

a medical instrument operable to be navigated through the anatomical body during the medical procedure;

at least one field sensor associated with the medical instrument and operable to be moved in association with the medical instrument;

at least one magnetic field source operable to radiate at least one magnetic field into the anatomical body and operable to be detected by the at least one field sensor;

a controller operable to receive from the at least one field sensor signals indicative of the at least one magnetic field and operable to continuously ascertain positions of the at least one field sensor based upon the at least one magnetic field detected by the at one least field sensor; and

a display operable to continuously display representations of the position of the at least one field sensor associated with the medical instrument as it moves from a first position to a second position, wherein the continuous representations include a representation of the first position, a representation of the second position, and representations of the positions between the first position and the second position

wherein the continuous representations of the position of the at least one field sensor is operable to be rotated in any direction on the display to illustrate the continuous representations from a plurality of perspectives of the continuous representations;

wherein the at least one magnetic field source includes a first magnetic field source operable to generate a first magnetic field, a second magnetic field source operable to generate a second magnetic field and a third magnetic field source operable to generate a third magnetic field wherein each of the first magnetic field source, the second magnetic field source, and the third magnetic field source each is a coil positioned orthogonally to the others about a first common origin.

85. The medical navigation apparatus of claim 84, further comprising a fourth magnetic field source, a fifth magnetic field source, and a sixth magnetic field source, each defined by a coil positioned orthogonally about a second common origin;

a seventh magnetic field source, an eighth magnetic field source, and a ninth magnetic field source each defined by a coil positioned orthogonally about a third common origin;

wherein each of the first common origin, the second common origin, and the third common origin, are positioned substantially in a two-dimensional plane.