Electrosurgical device with improved visibility

• US 20050159797A1
• Filed: 03/15/2005
• Published: 07/21/2005
• Est. Priority Date: 03/07/2003
• Status: Active Grant

• Current Assignee: Avent Incorporated (Avanos Medical, Inc.)
• Original Assignee: Baylis Medical Company Inc. (Boston Scientific Corporation)
• Inventors: Shah, Krishan, Chandran, Subashini
• Granted Patent: US 7,593,778 B2
• Time in Patent Office: Days
• US Class Current: 607/99
• CPC Class Codes: A61B 18/1477 Needle-like probes
• CPC Class Codes: A61B 2090/3966 Radiopaque markers visible in an X-ray image
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61N 1/06 for high-frequency therapy
• CPC Class Codes: A61N 1/36017 with leads or electrodes penetrating the skin
• CPC Class Codes: A61N 1/36021 for treatment of pain
• CPC Class Codes: A61N 1/40 Applying electric fields by inductive or capacitive coupling microwave apparatus A61N5/00; Applying radio-frequency signals

Abstract

A method and apparatus are disclosed for improving accuracy of placement of a cannula during delivery of electrical energy proximate to bodily tissue, e.g. neural structures. The apparatus optionally includes a cannula operable to deliver electrical current where a portion of the cannula is electrically insulated and a portion of the cannula is exposed and electrically conductive. The cannula further includes a radiopaque marker to identify a specific portion of the cannula, for example to differentiate the electrically insulated region from the electrically exposed region, by allowing it to be more clearly delineated using fluoroscopy or other radiographic imaging techniques. The radiopaque marker is optionally tapered in order to reduce the force required to insert a cannula comprising a radiopaque marker into the patient'"'"'s body.

Claims

1. A radiopaque cannula for insertion into a patient'"'"'s body, the cannula comprising:

a radiopaque elongate member, having a proximal end and a distal end and defining a lumen therebetween; and

a radiopaque marker associated with the elongate member for identifying a portion of said elongate member under radiographic imaging.

2. The cannula of claim 1, said radiopaque marker shaped to reduce a force required to insert said cannula into said patient'"'"'s body.

3. The cannula of claim 2, said radiopaque marker comprising a tapered distal end.

4. The cannula of claim 1, wherein said radiopaque marker comprises a material selected from the group consisting of platinum, iridium, gold, silver, tantalum and alloys thereof.

5. The cannula of claim 1, wherein said cannula comprises material selected from the group consisting of stainless steel, titanium and nitinol.

6. The cannula of claim 1, wherein at least a portion of said distal end is bent.

7. The cannula of claim 1, wherein said distal end defines an aperture in communication with said lumen.

8. The cannula of claim 1, further comprising a lateral aperture in communication with said lumen.

9. The cannula of claim 1, further comprising at least one marker selected from the group consisting of visual markers and tactile markers.

10. The cannula of claim 1, wherein said cannula is operable to connect to an energy source.

11. The cannula of claim 1, said elongate member being electrically conductive, said elongate member comprising:

an electrically insulated region; and

an electrically exposed region.

12. The cannula of claim 11, wherein said radiopaque marker is associated with at least one of said electrically insulated region and said electrically exposed region for distinguishing the exposed region from the insulated region under radiographic imaging.

13. The cannula of claim 1, further comprising a stylet, said stylet being insertable into said lumen.

14. The cannula of claim 13, wherein said stylet comprises a radiopaque marker.

15. A cannula for insertion into a patient'"'"'s body, said cannula comprising:

an elongate member; and

a means for improving radiographic visualization of said elongate member;

said means for improving radiographic visualization being associated with said elongate member and being shaped so as to reduce a force required to insert said elongate member into said patient'"'"'s body.

16. A system for delivering energy to a patient'"'"'s body, said system comprising:

an energy source;

a radiopaque cannula comprising an electrically conductive radiopaque elongate member, the elongate member comprising an electrically insulated region, an electrically exposed region and a radiopaque marker for distinguishing the insulated region from the exposed region using radiographic imaging techniques;

a means of delivering energy from said energy source to said cannula; and

a reference electrode.

17. The system of claim 16, said radiopaque marker shaped for reducing a force required to insert said cannula into said patient'"'"'s body.

18. A method for treating pain by delivering energy to a patient'"'"'s body, comprising the steps of:

(i) providing an electrically conductive radiopaque cannula comprising an electrically insulated region, an electrically exposed region and a radiopaque marker for distinguishing the insulated region from the exposed region;

(ii) positioning said electrically exposed region proximate a region of tissue to be treated;

(iii) determining a position of said electrically exposed region by identifying a location of said radiopaque marker using radiographic imaging techniques at least one of before and after step (ii); and

(iv) delivering energy through the cannula to said region of tissue to be treated;

whereby the energy is delivered to relieve pain.

19. The method of claim 18, said radiopaque marker shaped for reducing a force required to insert said cannula into said patient'"'"'s body.

20. The method of claim 18, wherein the tissue to be treated is neural tissue.

21. The method of claim 20, wherein the neural tissue is located proximate to or within a facet joint of a patient'"'"'s spine.