Micro-resecting and evoked potential monitoring system and method

• US 8,016,846 B2
• Filed: 06/02/2006
• Issued: 09/13/2011
• Est. Priority Date: 10/27/2005
• Status: Active Grant

• Current Assignee: Medtronic Xomed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Xomed Incorporated (Medtronic Plc)
• Inventors: McFarlin, Kevin, Reinker, David
• Primary Examiner(s): Hughes; S. Thomas
• Assistant Examiner(s): MILES, JONATHAN WADE
• Application Number:
  US11/446,520
• Publication Number:
  US 20070100336A1
• Time in Patent Office: 1,929 Days
• Field of Search: 606/167, 606/170, 606/171, 606177-180
• US Class Current: 606/170
• CPC Class Codes: A61B 17/1622 Drill handpieces A61B17/1626, A61B17/1628 take precedence
• CPC Class Codes: A61B 17/1626 Control means; Display units
• CPC Class Codes: A61B 17/1684 for the shoulder
• CPC Class Codes: A61B 17/1691 for the sternum
• CPC Class Codes: A61B 17/32002 with continuously rotating, oscillating or reciprocating cutting instruments
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 2017/00022 Sensing or detecting at the treatment site
• CPC Class Codes: A61B 2017/00119 alarm; indicating an abnormal situation
• CPC Class Codes: A61B 2017/00345 Micromachines, nanomachines, microsystems
• CPC Class Codes: A61B 2017/320032 Details of the rotating or oscillating shaft, e.g. using a flexible shaft
• CPC Class Codes: A61B 2090/08021 of the patient or his organs
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61B 5/4893 Nerves

Abstract

Surgical micro-resecting and evoked potential monitoring system and method. The system includes a micro-resecting instrument, handpiece, and evoked potential monitor. The instrument includes an outer tube forming a cutting window at which a cutting tip of an inner member is located. A hub assembly rotatably maintains the inner and outer members. An electrically non-conductive material covers a region of the outer tube, and wiring is connected to an exposed surface of the outer tube. The instrument defines a probe surface proximate the cutting window as part of an electrical pathway with the wiring. The hub assembly is powered by the handpiece, and the wiring is connected to the evoked potential monitor. Evoked potential monitoring is performed at the probe surface via stimulation energy delivered along the electrical pathway, and tissue/bone resection occurs with rotation of the cutting tip.

Claims

1. A method of perfouning a surgical micro-resecting procedure at a target site of a patient, the method comprising:

providing a micro-resecting instrument including;

an outer tubular member having a lumen, a proximal section, and a distal section forming a cutting window fluidly connected to a lumen,

an inner member disposed within the lumen and having a proximal portion and a distal portion, the distal portion including a cutting tip positioned at the cutting window upon final assembly,

a hub assembly maintaining the proximal section and the proximal portion,

an electrically non-conductive material covering a region of the outer tubular member distal the hub assembly,

wiring electrically connected to the outer tubular member,

wherein the instrument defines a probe surface proximate the cutting window, the probe surface characterized by the absence of the non-conductive material,

and further wherein an electrical pathway is established from the wiring to the probe surface,

electrically connecting the wiring to an evoked potential monitoring device such that an energy source of the evoked potential monitoring device is in electrical communication with the probe surface;

delivering the distal section of the outer tubular member toward the target site such that the cutting window is adjacent the target site;

applying a stimulation energy to the probe surface via the energy source and the wiring;

operating the evoked potential monitoring device to evaluate a proximity of the probe surface relative to a bodily structure of interest based upon reference to the applied stimulation energy;

rotating the inner member relative to the outer tubular member to perform a micro-resecting operation in which bodily material at the target site is resected by the cutting tip within the cutting window; and

attaching a motorized handpiece to the hub assembly such that operation of the handpiece causes the inner member to rotate relative to the outer tubular member, and further wherein the hub assembly electrically isolates the micro-resecting instrument from the handpiece.

2. The method of claim 1, wherein the evaluation of a proximity of the probe surface relative to a bodily structure of interest is indicative of a proximity of the cutting window relative to the bodily structure of interest.

3. The method of claim 1, wherein delivering the distal section toward the target site includes:

simultaneously performing evoked potential monitoring with movement of the distal section, whereby as the distal end is moved toward the target site, stimulation energy is delivered to the probe surface for evaluating a proximity of the probe surface relative to a bodily structure of interest.

4. The method of claim 1, wherein the micro-resecting operation and the proximity evaluation are performed simultaneously.

5. The method of claim 1, wherein rotating the inner member to perform a micro-resecting operation includes:

rotating the inner member for a first period of time;

applying a stimulation energy to the probe surface upon completion of the first period of time as part of a proximity evaluation; and

determining whether to rotate the inner member for a second period of time based upon the proximity evaluation.

6. The method of claim 1, further comprising:

automatically stopping rotation of the inner member based upon the evaluated proximity.

7. The method of claim 1, wherein the bodily structure of interest is a nerve.

8. The method of claim 1, wherein the bodily structure of interest is an ocular bone.

9. The method of claim 1, wherein the method is performed as part of an endoscopic procedure.

10. The method of claim 1, wherein the outer tubular member includes a curved region distal the hub assembly.

11. The method of claim 1, wherein the applied stimulation energy is characterized as not being RF energy.

12. The method of claim 1, wherein applying a stimulation energy is characterized by the absence of tissue cauterization at the target site.

13. The method of claim 1, wherein the probe surface is defined at least in part by an exposed distal region of the outer tubular member.

14. The method of claim 1, wherein the probe surface is defined at least in part by the cutting tip.

15. The method of claim 1, wherein the inner member folins a central lumen and an opening to the central lumen at the cutting tip, the method further comprising:

aspirating material from the target site through the opening and the central lumen.

16. A surgical micro-resecting system comprising:

a micro-resecting instrument including;

an outer tubular member having a lumen, a proximal section, and a distal section forming a cutting window fluidly connected to the lumen,

an inner member disposed within the lumen and having a proximal portion and a distal portion including a cutting tip positioned at the cutting window upon final assembly,

a hub assembly maintaining the proximal section and the proximal portion,

an electrically non-conductive material covering a region of the outer tubular member distal the hub assembly,

wiring electrically connected to the outer tubular member,

where the instrument defines a probe surface proximate the cutting window, the probe surface characterized by the absence of the non-conductive material,

and further wherein an electrical pathway is established from the wiring to the probe surface;

a motorized handpiece selectively coupled to the hub assembly for rotating the inner member relative to the outer tubular member wherein the hub assembly is configured to electrically isolate the micro-resecting instrument from the motorized handpiece; and

an evoked potential monitoring device having an energy source selectively coupled to the wiring for applying a stimulation energy to the probe surface via the wiring and configured to evaluate a proximity of the probe surface relative to a bodily structure of interest.

17. The system of claim 16, wherein the outer tubular member is curved along a length thereof distal the hub assembly.

18. The system of claim 16, wherein the motorized handpiece is electronically coupled to the evoked potential monitoring device and further wherein the evoked potential monitoring device is adapted to prompt disablement of the motorized handpiece based upon an evaluated proximity of the probe surface relative to a bodily structure of interest.

19. The system of claim 16, wherein the energy source is characterized as generating a low level stimulation energy that is not capable of cauterizing human tissue.

20. The system of claim 16, wherein the cutting window includes a plurality of teeth.

21. The system of claim 16, wherein the cutting tip includes a plurality of cutting teeth arranged about a mouth.

22. The system of claim 16, wherein the cutting tip is a bur.

23. The system of claim 16, wherein the probe surface is defined at least in part by an exposed distal region of the outer tubular member.

24. The system of claim 16, wherein the probe surface is defined at least in part by the cutting tip.

25. The system of claim 16, further comprising:

an irrigation pathway terminating adjacent the cutting window; and

an irrigation source fluidly connected to the irrigation pathway.

26. The system of claim 25, wherein the irrigation pathway is formed between the inner and outer tubular members.

27. The system of claim 25, wherein the irrigation pathway includes a tube assembled to an exterior of the outer tubular member.

28. The system of claim 16, wherein the instrument further includes an electrical coupling establishing a continuous electrical communication between the wiring and the inner tubular member.

29. The system of claim 16, wherein the inner member is tubular, defining a central lumen.