Flexible microwave catheters for natural or artificial lumens

• US 10,363,094 B2
• Filed: 04/09/2012
• Issued: 07/30/2019
• Est. Priority Date: 04/08/2011
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Covidien LP (Medtronic Plc)
• Inventors: Brannan, Joseph D., Case, Jason A, Ladtkow, Casey M., Smith, Kurt R.
• Primary Examiner(s): Hulbert, Amanda K
• Assistant Examiner(s): So, Elizabeth K
• Application Number:
  US13/442,831
• Publication Number:
  US 20120259326A1
• Time in Patent Office: 2,668 Days
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• 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 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 18/1815 using microwaves
• CPC Class Codes: A61B 2017/00323 Cables or rods
• CPC Class Codes: A61B 2018/00023 closed, i.e. without wound contact by the fluid
• CPC Class Codes: A61B 2018/00077 high, i.e. electrically conducting
• CPC Class Codes: A61B 2018/00172 Connectors and adapters therefor
• CPC Class Codes: A61B 2018/0022 Balloons
• CPC Class Codes: A61B 2018/00226 extending from a surface, i.e. Blisters
• CPC Class Codes: A61B 2018/00232 having an irregular shape
• CPC Class Codes: A61B 2018/00267 having a basket shaped structure
• CPC Class Codes: A61B 2018/00273 Anchoring means for temporary attachment of a device to tissue
• CPC Class Codes: A61B 2018/00285 Balloons
• CPC Class Codes: A61B 2018/00345 Vascular system
• CPC Class Codes: A61B 2018/00434 Neural system
• CPC Class Codes: A61B 2018/00511 Kidney
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/1846 : Helical antennas
• CPC Class Codes: A61B 2018/1861 : with an instrument inserted into a body lumen or cavity, e.g. a catheter
• CPC Class Codes: A61B 2018/1884 : with non-uniform emissions
• CPC Class Codes: A61B 2018/1892 : Details of electrical isolations of the antenna
• CPC Class Codes: A61B 90/10 : for stereotaxic surgery, e.g. frame-based stereotaxis
• CPC Class Codes: A61N 5/022 : Apparatus adapted for a specific treatment

Abstract

A method for forming a resonating structure within a body lumen, the method including advancing a flexible microwave catheter into a body lumen of a patient, the flexible microwave catheter including a radiating portion at the distal end of the flexible microwave catheter, the radiating portion configured to receive microwave energy, and at least one centering device proximate the radiating portion configured to deploy radially outward from the flexible microwave catheter; positioning the radiating portion near tissue of interest; deploying the at least one centering device radially outward from the flexible microwave catheter within the body lumen such that a longitudinal axis of the radiating portion is substantially parallel with and at a fixed distance from a longitudinal axis of the body lumen near the targeted tissue; and delivering microwave energy to the radiating portion such that a circumferentially balanced resonating structure is formed with the body lumen.

Claims

1. A method for forming a resonating structure within a body lumen, the method comprising:

advancing a flexible microwave catheter into a body lumen of a patient, the flexible microwave catheter including;

an outer sheath;

a radiating portion disposed within the outer sheath at a distal end of the flexible microwave catheter; and

a centering device proximate the radiating portion in a confined condition within the outer sheath;

positioning the radiating portion near targeted tissue;

distally advancing the centering device relative to the outer sheath while the outer sheath is in a fixed position along a longitudinal axis of the flexible microwave catheter, wherein distally advancing the centering device causes deployment of the centering device radially outward from the confined condition within the outer sheath to an unconfined condition distal the outer sheath within the body lumen, such that the radiating portion is at a radial center of the body lumen and a longitudinal axis of the radiating portion is substantially parallel with and at a fixed distance from a longitudinal axis of the body lumen near the targeted tissue; and

delivering microwave energy to the radiating portion such that a circumferentially balanced resonating structure is formed with the body lumen.

2. The method of claim 1, wherein the circumferentially balanced resonating structure radiates energy 360 degrees around the longitudinal axis of the radiating portion and along a longitudinal span of about 2 cm to about 3 cm.

3. The method of claim 1, wherein the body lumen is a renal artery.

4. The method of claim 3, wherein the targeted tissue is one or more renal nerves and the circumferentially balanced resonating structure generates an electromagnetic field that denervates the targeted tissue.

5. The method of claim 1, further comprising:

providing a continuous fluid flow within the body lumen; and

cooling at least a portion of the body lumen.

6. The method of claim 5, further comprising:

monitoring a temperature of the continuous fluid flow; and

terminating delivery of microwave energy if the monitored temperature exceeds a threshold temperature.

7. The method of claim 1, further comprising:

continuing delivery of microwave energy until a sufficient amount of energy is delivered to effectively damage the targeted tissue while preserving a critical structure of the body lumen.

8. The method of claim 1, wherein the body lumen is at least one of a gastrointestinal lumen, an auditory lumen, a respiratory system lumen, a urinary system lumen, a female reproductive system lumen, a male reproductive system lumen, a vascular system lumen, or an internal organ.

9. The method of claim 1, further comprising expanding the body lumen to form a structure related to the microwave frequency.

10. The method of claim 1, further comprising delivering microwave energy at a frequency that is selected to be resonate with the body lumen.

11. The method of claim 1, further comprising:

monitoring a temperature within the body lumen; and

terminating delivery of the microwave energy when the monitored temperature exceeds a threshold temperature.

12. The method of claim 1, wherein the radiating portion includes a feed gap forming an open circuit in the flexible microwave catheter.

13. The method of claim 1, wherein the radiating portion includes a first feed gap and a second feed gap, and wherein the first and second feed gaps each form open circuits in the flexible microwave catheter.