Trajectory guide with instrument immobilizer

• US 20020049451A1
• Filed: 08/17/2001
• Published: 04/25/2002
• Est. Priority Date: 08/17/2000
• Status: Active Grant

• Current Assignee: Image Guided Neurologics, Inc. (Medtronic Plc)
• Original Assignee: Image Guided Neurologics, Inc. (Medtronic Plc)
• Inventors: Parmer, Kari, David, John, Miller, Thomas I.
• Granted Patent: US 6,902,569 B2
• Time in Patent Office: Days
• US Class Current: 606/108
• CPC Class Codes: A61B 2017/347 Locking means, e.g. for locking instrument in cannula
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61B 2090/3933 Liquid markers
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 90/11 with guides for needles or instruments, e.g. arcuate slides or ball joints

Abstract

A method and apparatus accurately maintains alignment of a surgical instrument. The apparatus includes a base with an attached movable member. The movable member includes a passage forming a portion of a trajectory path. A relaxable or rigid material has a similar passage in common with the passage of the movable member. If a relaxable material is used, the passage portion of the relaxable region is held open by an inserted stem removably attached to the movable member. The instrument is then inserted into the center of the stem and thus into the trajectory path. The stem is removed by withdrawing it from the movable member over the proximal portion of the instrument. This releases the relaxable region to tightly hold the instrument in place. Alternatively, using a relaxable or rigid component, the component is slid laterally to at least partially offset a passage through the component from the passage of the movable member to reduce a combined effective area of the passages and to grasp an instrument.

Claims

1. A device for immobilizing a surgical instrument, including:

a base;

a movable member coupled to the base yet capable of rotating with respect to the base, the movable member including a first passage sized and shaped to substantially immobilize the instrument with respect to the movable member.

2. The device of claim 1, further including a stem including an opening, the stem and movable member fitting with each other such that the opening in the stem substantially aligns with the first passage of the movable member.

3. The device of claim 2, in which the stem carries at least one locator readable by a remote imaging system.

4. The device of claim 1, in which the base includes a groove sized and shaped to accept the instrument after the instrument has been laterally bent into the groove.

5. The device of claim 1, in combination with a locking member that engages and fixes the movable member upon tightening of the locking member when the movable member is properly positioned with respect to the device.

6. The device of claim 1, in which the base includes a mounting seat, sized and shaped to receive at least a portion of the movable member, and a collar, sized and shaped to receive at least a portion of a locking member, the collar including a coupler to detachably engage the mounting seat.

7. The device of claim 6, in which the coupler is selected from at least one of a snap-fit leg and a screw.

8. The device of claim 1, further including a material coupled to the movable member, in which the first passage of the movable member extends through the material coupled to the movable member, and the material coupled to the movable member is sized and shaped to immobilize the instrument with respect to the movable member.

9. The device of claim 8, in which the material is within the movable member.

10. The device of claim 8, in which the material is within the base but outside of the movable member.

11. The device of claim 8, in which the material is selected from at least one of a rigid material, a semi-rigid material, and a relaxable material.

12. The device of claim 1, in which the movable member includes a two-piece ball assembly carrying a relaxable cylindrical stabilizer, the ball and stabilizer having a coaxially aligned passage therethrough, and in which the base includes:

a mounting seat, including a flange and a hemispherically sized and shaped seat to receive at least a portion of the ball; and

a collar, sized and shaped to receive at least a portion of a locking member, the collar including a coupler to detachably engage the mounting seat.

13. The device of claim 12, further including:

a locking member threadedly engaging the collar; and

a guide stem, threadedly engaging the first passage of the movable member and holding open the passage through the relaxable stabilizer, the guide stem including a passage coaxially aligned to the first passage of the movable member.

14. The device of claim 1, in which the movable member includes a slide having a second passage sized and shaped to be aligned with the first passage to allow an instrument to be passed therethrough, the second passage also sized and shaped to be at least partially offset from the first passage to reduce an effective area of the first passage to grasp the instrument.

16. The method of claim 15, including providing a base and a movable member coupled to the base yet capable of rotating with respect to the base, the movable member including a second passage aligned with the first passage.

17. The method of claim 16, including, aiming a trajectory formed by the commonly-aligned first passage and the second passage of the movable member using at least one imagable locator along the trajectory.

18. The method of claim 16, in which the base includes a groove, and further including laterally bending the instrument into the groove.

19. The method of claim 16, in which the providing the material includes providing a relaxable material, and further including providing a stem spreading the relaxable material around the first passage, and in which the reducing the effective area includes relaxing the relaxable material includes removing the stem over the introduced instrument.

20. The method of claim 19, further including providing a locking member, and engaging the locking member to the base to fix the movable member in place before removing the stem.

21. The method of claim 20, in which providing the base includes providing a mounting seat receiving the movable member and a detachable collar receiving the locking member, and further including, after removing the stem:

removing the locking member; and

removing the collar.

22. The method of claim 15, in which the providing the material includes providing a relaxable material, and in which the reducing the effective area of the material around the instrument includes relaxing the relaxable material around the instrument.

23. The method of claim 15, further including providing a slidable component having a second passage substantially aligned with the first passage, introducing the instrument into the substantially aligned first and second passages, and in which the reducing the effective area of the material around the instrument includes at least partially offsetting the second passage from the first passage to immobilize the instrument.

24. The method of claim 23, in which the at least partially offsetting the second passage from the first passage includes sliding the second passage with respect to the first passage.

15. A method of immobilizing an instrument, including:

providing a material having a first passage;

introducing the instrument into the first passage; and

reducing an effective area of the material around the instrument to immobilize the instrument with respect to the material.