Ablation apparatus with ultrasonic imaging capabilities

• US 5,876,340 A
• Filed: 04/17/1997
• Issued: 03/02/1999
• Est. Priority Date: 04/17/1997
• Status: Expired due to Term

• Current Assignee: Irvine Biomedical, Inc. (Abbott Laboratories)
• Original Assignee: Irvine Biomedical, Inc. (Abbott Laboratories)
• Inventors: Tu, Hosheng, Chia, Weng-Kwen Raymond
• Primary Examiner(s): Jaworski, Francis J.
• Application Number:
  US08/840,905
• Time in Patent Office: 684 Days
• Field of Search: 600/439, 600/458, 600/461-463, 600/471, 600/381, 606/41, 607/116, 607/101-102, 607/120, 607/122, 607/126-128
• US Class Current: 600/439
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 18/1815 using microwaves
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/0091 Handpieces of the surgical instrument or device
• CPC Class Codes: A61B 2018/1412 Blade
• CPC Class Codes: A61B 2090/3782 transmitter or receiver in catheter or minimal invasive instrument
• CPC Class Codes: A61B 2090/3925 ultrasonic

Abstract

An RF ablation apparatus has a delivery catheter with distal and proximal ends. A handle is attached to the proximal end of the delivery catheter. The delivery catheter has an electrode deployment means where said electrode deployment means includes a retractable tip section comprising a deployable electrode with portion of one side having a sharp edge. The tip section has a non-deployed state when it is positioned in the delivery catheter. On the other hand, the tip section has a distended deployed state when it is advanced out of the distal end of said delivery catheter. The deployed tip section has a preformed shape while the farther distal deployed electrode defines an ablation target along with portion of the forward side having a sharp edge on said electrode. The forward edge of the deployed electrode has a slightly curvature or an essentially straight shape. Said deployable electrode has ultrasonic imaging capabilities.

Claims

1. An ablation apparatus comprising:

(a) a delivery catheter with a distal section, a distal end, a proximal end, and a lumen extending therebetween, wherein a wire having a distal end and a proximal end is located within the lumen of the delivery catheter;

(b) a handle attached to the proximal end of said delivery catheter, wherein a push-pull mechanism is located within the handle, and wherein the proximal end of the wire is attached to the push-pull mechanism;

(c) an electrode deployment means positioned at the proximal end of the wire, wherein the wire comprises a retractable tip section;

the catheter, handle, wire, and deployment means being adapted to cooperate to house non-deploy and deploy the tip section;

(d) an electrode mounted on the retractable tip section, wherein the electrode has a front side adapted to contact the tissue when the retractable tip section is deployed; and

(e) ultrasonically visible markers mounted on the distal catheter tip on the electrode.

2. The ablation apparatus as in claim 1, further comprising a preformed shape for the retractable tip section, wherein the tip section extends outwardly to one side of the delivery catheter when it is deployed.

3. The ablation apparatus as in claim 2, further comprising a torsion spring for the at least one electrode mounted on the retractable tip section, wherein the electrode bends inwardly to the opposite side of the delivery catheter with respect to the tip section.

4. The ablation apparatus of claim 3, wherein a portion of the front side of the electrode has an essentially straight edge.

5. The ablation apparatus as in claim 3, further comprising a steering mechanism at the handle for controlling the deflection of the distal section of said delivery catheter.

6. The ablation apparatus of claim 5, wherein the front side of the electrode has a slightly circular shape.

7. The ablation apparatus of claim 5, wherein the front side of the electrode has sections with plurality of curvatures.

8. The ablation apparatus as in claim 5, further comprising a temperature sensor mounted on the electrode and a closed-loop temperature controller, wherein the temperature sensor provides sensing signals for the closed-loop controller for the ablation apparatus.

9. The ablation apparatus of claim 3, wherein the electrode is consisted of blunt sides except a portion of the front side has a sharp edge wherein said sharp edge comprises a conductive surface adapted for RF energy delivery.

10. The ablation apparatus as in claim 3, further comprising ultrasonic probes on the front side of the electrode having ultrasonic signals being directed outwardly and received inwardly relative to the probes which are adapted to advance along with the front side of said electrode.

11. The ablation apparatus of claim 5, wherein the front side of the electrode has a sharp edge.

12. A method for operating an ablation apparatus system inside the body of a patient for ablating a target tissue, the ablation apparatus system comprising a delivery catheter with a distal section, a distal end, a proximal end, and a lumen extending therebetween, wherein a wire having a distal end and a proximal end is located within the lumen of the delivery catheter;

a handle attached to the proximal end of said delivery catheter, wherein a push-pull mechanism is located within the handle, and wherein the proximal end of the wire is attached to the push-pull mechanism;

an electrode deployment means positioned at the proximal end of the wire, wherein the wire comprises a retractable tip section;

the catheter, handle, wire, and deployment means being adapted to cooperate to house non-deploy and deploy the tip section;

an electrode mounted on the retractable tip section, wherein the electrode has a front side adapted to contact the tissue when the retractable tip section is deployed;

ultrasonically visible markers mounted on the distal catheter tip on the electrode, and an external RF generator, wherein RF is applied by the catheter electrode for ablation purposes;

the method comprising;

(a) introducing the delivery catheter having a retractable tip section under a non-deployed state into the body through a small surgery hole or through the natural body openings;

(b) once approaching the target tissue, deploying the tip section by operating the push-pull mechanism at the handle;

(c) moving the electrode to the proximity of the target tissue guided by the ultrasonically visible markers;

(d) once positioned at the target tissue, encircling the target tissue; and

(e) by a simultaneous or alternate mode, gradually pushing forward the delivery catheter against the target tissue and applying RF by the catheter electrode to the tissue.

13. The method for operating an ablation apparatus system inside the body of a patient for ablating a target tissue as in claim 12, further comprising treating body tissue selecting from removal of prostatic adenomas, bladder tumors, uterus tumors, urethra tumors, and intestinal polyps by loosening the tissue and applying RF energy in a simultaneous mode, alternate mode, or a combination thereof.

14. An ablation apparatus comprising:

(a) a delivery catheter with a distal section, a distal end, a proximal end, and a lumen extending therebetween, wherein a wire having a distal end and a proximal end is located within the lumen of the delivery catheter;

(b) a handle attached to the proximal end of said delivery catheter, wherein a push-pull mechanism is located within the handle, and wherein the proximal end of the wire is attached to the push-pull mechanism;

(c) an electrode deployment means positioned at the proximal end of the wire, wherein the wire comprises a retractable tip section;

the catheter, handle, wire, and deployment means being adapted to cooperate to house non-deploy and deploy the tip section;

(d) an electrode mounted on the retractable tip section, wherein the electrode has a front side adapted to contact the tissue when the retractable tip section is deployed, and wherein the electrode is consisted of blunt sides except a portion of the front side having a sharp edge to loosen the target tissue for improved ablation treatment with RF energy delivery; and

(e) ultrasonically visible markers mounted on the distal catheter tip on the electrode.