Methods and devices for controlling ablation therapy

• US 9,937,000 B2
• Filed: 08/18/2016
• Issued: 04/10/2018
• Est. Priority Date: 04/12/2011
• Status: Expired due to Fees

• Current Assignee: Thermedical, Inc.
• Original Assignee: Thermedical, Inc.
• Inventors: Curley, Michael G.
• Primary Examiner(s): Holmes, Rex R
• Application Number:
  US15/240,693
• Publication Number:
  US 20160354138A1
• Time in Patent Office: 600 Days
• CPC Class Codes: A61B 18/04 by heating by applying electromagnetic radiation A61B18/18; hyperthermia using electric or magnetic fields, radiation or ultrasound A61N
• CPC Class Codes: A61B 18/082 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1477 Needle-like probes
• CPC Class Codes: A61B 18/16 Indifferent or passive electrodes for grounding
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61B 2018/00041 Heating, e.g. defrosting
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/00773 Sensed parameters
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00797 measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/00809 measured thermochromatically
• CPC Class Codes: A61B 2018/00821 measured by a thermocouple
• CPC Class Codes: A61B 2018/046 in liquid form
• CPC Class Codes: A61B 2018/1425 Needle
• CPC Class Codes: A61B 2018/162 located on the probe body
• CPC Class Codes: F04B 17/03 driven by electric motors
• CPC Class Codes: F04B 19/22 of reciprocating-piston type
• CPC Class Codes: F04B 41/02 having reservoirs
• CPC Class Codes: F04B 43/04 : Pumps having electric drive
• CPC Class Codes: F04B 49/06 : Control using electricity regulating by means of floats actuating electric switches F04B49/04
• CPC Class Codes: F04C 2270/041 : Controlled or regulated
• CPC Class Codes: Y10T 29/49016 : Antenna or wave energy "plumbing" making
• CPC Class Codes: Y10T 29/49085 : Thermally variable

Abstract

Devices and methods for controlling ablation therapy are provided herein. In one embodiment, an ablation device is provided that includes an elongate body having proximal and distal ends, and an inner lumen extending therethrough. The inner lumen can be configured to receive fluid therein and to deliver fluid to the distal end of the elongate body. The device can also include an ablation element positioned at a distal end of the elongate body that is configured to heat surrounding tissue, and a heater element disposed within the inner lumen adjacent to a distal end of thereof, the heater element being configured to heat fluid flowing through the inner lumen.

Claims

1. A method of ablating tissue, comprising:

positioning a blunt distal portion of an elongate body in contact with tissue;

delivering ablative energy to the tissue through an ablation element on the blunt distal portion of the elongate body;

delivering fluid from a proximal end to a distal end of the elongate body through a delivery lumen within an inner lumen of the elongate body;

returning fluid from the distal end to the proximal end of the elongate body through a return lumen within the inner lumen of the elongate body without releasing the fluid into tissue;

heating the fluid to a temperature greater than 37°

C. and less than 100°

C. using a heater element disposed in a distal portion of the elongate body;

wherein heating the fluid using a heater element includes passing electrical current through at least one wire that extends through at least one spacer to pass energy through fluid flowing through the inner lumen of the elongate body;

wherein the at least one spacer is configured to maintain a position of the at least one wire within he inner lumen of the elongate body, and

wherein heating the fluid using a heater element includes passing electrical current from a first power source between a single wire and a conductive elongate body.

2. The method of claim 1, wherein the blunt distal portion of the elongate body does not penetrate the tissue.

3. The method of claim 1, wherein the ablation element is positioned at the distal end of the elongate body and adjacent to the tissue.

4. The method of claim 1, wherein the heater element is disposed within the inner lumen to heat the fluid.

5. The method of claim 1, further comprising detecting the temperature of the tissue in contact with the blunt distal portion of the elongate body using a temperature sensor disposed on a distal end of the elongate body.

6. The method of claim 1, further comprising detecting the temperature of the fluid delivered through the elongate body using a temperature sensor disposed distal to the heater element.

7. The method of claim 6, further comprising adjusting an output level of any of the ablation element and the heater element to maintain the temperature of the ablation element above 37°

C. and below 100°

C.

8. The method of claim 1, wherein delivering ablative energy to the tissue through an ablation element includes passing electrical current from a second power source between the conductive elongate body and a collector electrode positioned outside the inner lumen.

9. The method of claim 1, wherein the return lumen is defined by the annular space between the delivery lumen and an inner wall of the elongate body inner lumen.

10. The method of claim 1, wherein the delivery lumen and the return lumen are each separate hollow tubes disposed within the inner lumen of the elongate body.

11. The method of claim 1, wherein the delivery lumen is positioned within the inner lumen of the elongate body such that it does not move with respect to the elongate body.

12. The method of claim 1, wherein the delivery lumen floats freely within the inner lumen of the elongate body.

13. A method of ablating tissue, comprising:

positioning a blunt distal portion of an elongate body in contact with tissue;

delivering ablative energy to the tissue through an ablation element on the blunt distal portion of the elongate body;

delivering fluid from a proximal end to a distal end of the elongate body through a delivery lumen within an inner lumen of the elongate body;

returning fluid from the distal end to the proximal end of the elongate body through a return lumen within the inner lumen of the elongate body without releasing the fluid into tissue;

heating the fluid to a temperature greater than 37°

C. and less than 100°

C. using a heater element disposed in a distal portion of the elongate body;

wherein heating the fluid using a heater element includes passing electrical current through at least one wire that extends through at least one spacer to pass energy through fluid flowing through the inner lumen of the elongate body;

wherein the at least one spacer is configured to maintain a position of the at least one wire within the inner lumen of the elongate body; and

wherein heating the fluid using a heater element includes passing electrical current through two wires that extend through two spacers.

14. The method of claim 13, wherein the blunt distal portion of the elongate body does not penetrate the tissue.

15. The method of claim 13, wherein the ablation element is positioned at the distal end of the elongate body and adjacent to the tissue.

16. The method of claim 13, further comprising detecting the temperature of the tissue in contact with the blunt distal portion of the elongate body using a temperature sensor disposed on a distal end of the elongate body.

17. The method of claim 13, further comprising detecting the temperature of the fluid delivered through the elongate body using a temperature sensor disposed distal to the heater element.

18. The method of claim 17, further comprising adjusting an output level of any of the ablation element and the heater element to maintain the temperature of the ablation element above 37°

C. and below 100°

C.

19. The method of claim 13, wherein the return lumen is defined by the annular space between the delivery lumen and an inner wall of the elongate body inner lumen.

20. The method of claim 13, wherein the delivery lumen and the return lumen are each separate hollow tubes disposed within the inner lumen of the elongate body.

21. The method of claim 13, wherein the delivery lumen is positioned within the inner lumen of the elongate body such that it does not move with respect to the elongate body.

22. The method of claim 13, wherein the delivery lumen floats freely within the inner lumen of the elongate body.