Multifaceted tracker device for computer-assisted surgery

• US 8,386,022 B2
• Filed: 11/02/2006
• Issued: 02/26/2013
• Est. Priority Date: 11/03/2005
• Status: Active Grant

• Current Assignee: ORTHOsoft ULC. (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Orthosoft Inc. (Zimmer Biomet Holdings, Inc.)
• Inventors: Amiot, Louis-Philippe, Jutras, Sbastien, Pelletier, Benot
• Primary Examiner(s): Le, Long V.
• Assistant Examiner(s): EVOY, NICHOLAS LANE
• Application Number:
  US11/555,947
• Publication Number:
  US 20070100325A1
• Time in Patent Office: 2,308 Days
• Field of Search: 600/417, 600/424, 600/427, 600/429, 600/473, 606/130
• US Class Current: 600/429
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/256 having a database of accessory information, e.g. including context sensitive help or scientific articles
• CPC Class Codes: A61B 2090/3983 Reference marker arrangements for use with image guided surgery
• 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 90/39 Markers, e.g. radio-opaque or breast lesions markers

Abstract

A tracker device of the type is associated with a surgical instrument and being trackable in space by a CAS system such that a position of the surgical instrument is calculable. A support is adapted to be connected to the surgical instrument. Optical elements are mounted to the support in a first pattern so as to be detectable by the CAS system along a first range of visibility. Other optical elements are mounted to the support in a second pattern so as to be detectable by the CAS system along a second range of visibility, with the first range of visibility and the second range of visibility having at most a common portion, whereby a position of the surgical instrument is tracked within the first and the second range of visibility as a function of the detection of any one of the patterns of the optical elements.

Claims

1. A tracker device of the type being associated with a surgical instrument and being trackable in space by a CAS system such that at least a position of the surgical instrument is calculable, comprising:

a support adapted to be connected to the surgical instrument and supporting at least four different optical elements;

at least three optical elements each having a single flat retro-reflective surface and being mounted to the support in a first pattern so as to be detectable by the CAS system along a first range of visibility, with the first pattern defining a first polygon with each corner of the first polygon being a point in a respective one of the three optical elements; and

at least three other optical elements separate from said three optical elements, the at least three other optical elements each having a single flat retro-reflective surface and being mounted to the support in a second pattern, with the second pattern defining a second polygon geometrically different from the first polygon, with each corner of the second polygon being a point in a respective one of the three other optical elements so as to be detectable by the CAS system along a second range of visibility, with the first range of visibility and the second range of visibility having at most a common portion;

whereby at least a position of the surgical instrument is tracked within the first and the second range of visibility as a function of the detection and identification of any one of the first polygon and the second polygon of the optical elements.

2. The tracker device according to claim 1, wherein the flat retro-reflective surfaces of the at least three optical elements are on separate planes and parallel to a same first plane, and the flat retro-reflective surfaces of the at least three other optical elements are on separate planes and parallel to a same second plane, the first plane and the second plane being solely in an unparallel relation.

3. The tracker device according to claim 2, wherein the first polygon has three of the at least three optical elements in a first triangle, and the second polygon has three of the at least three other optical elements in a second triangle, whereby the surgical instrument is trackable for position and orientation.

4. The tracker device according to claim 1, further comprising at least three further other optical elements mounted to the support in a third pattern, with the third pattern defining a third polygon geometrically different from the first polygon and the second polygon, with each corner of the third polygon being a point in a respective one of the three further other optical elements so as to be detectable by the CAS system along a third range of visibility, with the third range of visibility and at least one of the first range and the second range of visibility having at most a common portion.

5. The tracker device according to claim 1, wherein each optical element is formed by an annular cap secured to the support, and a reflective member with the flat retro-reflective surface held captive to the support by the annular cap, an opening in the annular cap being opposite the reflective member so as to define a geometry of the optical element.

6. The tracker device according to claim 5, wherein the annular cap is releasably secured to the support so as to change reflective members after use.

7. The tracker device according to claim 5, wherein the reflective members are each in a concavity defined by the annular cap, so as to be protected from accidental contact.

8. The tracker device according to claim 7, wherein the concavity has a beveled surface surrounding the reflective member to increase a range of visibility of the reflective member.

9. The tracker device according to claim 1, wherein each of the optical elements is circular.

10. The tracker device according to claim 1, wherein the support has a first connection configuration so as to be releasably connected to a first size of surgical instrument, and a second connection configuration so as to be releasably connected to a second size of surgical instrument.

11. A computer-assisted surgery system for tracking surgical instruments during surgery, comprising:

at least one surgical instrument;

a tracker device secured to the surgical instrument, the tracker device having at least six optical elements, with a first geometrical pattern of at least a first, a second and a third optical elements visible along a first range of visibility, with the first geometrical pattern defining a first polygon with each corner of the first polygon being a point in a respective one of the three optical elements, and a second geometrical pattern of at least a fourth, a fifth and a sixth optical elements separate from the first, the second and the third optical elements and visible along a second range of visibility, with the second pattern defining a second polygon geometrically different from the first polygon, with each corner of the second polygon being a point in a respective one of the three other optical elements;

a tracking system having;

a sensor unit tracking a visible one of the geometrical patterns depending on which of the first range of visibility and the second range of visibility is in a line of sight of the sensor unit as the instrument is moved;

a database storing geometrical pattern data and instrument/tracker device relation data; and

a position and orientation calculator to identify either one of the geometrical pattern being tracked from the geometrical pattern data, and to calculate a position and orientation of the tracker device as a function of the tracking of the identified geometrical pattern from the sensor unit;

the tracking system calculating a position and orientation of the instrument as a function of the position and orientation of the tracker device and of the instrument/tracker device relation data.

12. The computer-assisted surgery system according to claim 11, wherein the instrument/tracker device relation data is obtained by calibration.

13. The computer-assisted surgery system according to claim 11, wherein the tracker device has a third geometrical pattern of a seventh, an eighth and a ninth optical elements visible along a third range of visibility, with the third pattern defining a third polygon geometrically different from the first polygon and the second polygon, with each corner of the third polygon being a point in a respective one of the three further other optical elements.