Flexible microwave catheters for natural or artificial lumens

• US 10,314,652 B2
• Filed: 05/23/2016
• Issued: 06/11/2019
• 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.
• Primary Examiner(s): Peffley, Michael F
• Application Number:
  US15/161,382
• Publication Number:
  US 20160278859A1
• Time in Patent Office: 1,114 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 microwave delivery device, including a coaxial feedline having an inner conductor, an inner dielectric insulator coaxially disposed about the inner conductor, and an outer conductor coaxially disposed about the inner dielectric, and a radiating portion operably coupled to a distal end. The radiating portion includes a radiating portion inner conductor operable coupled to and extending from a distal end of the coaxial feedline inner conductor, a shielding outer conductor helically wrapped about the radiating portion inner conductor and operably coupled to the coaxial feedline outer conductor; and a shielding dielectric positioned between the radiating portion inner conductor and the shielding outer conductor wherein the width of the shielding outer conductor varies according to the longitudinal position thereof along the coaxial feedline inner conductor, and a cap operably coupled to a distal end of the radiating portion inner conductor and the shielding outer conductor to provide an electrical connection therebetween.

Claims

1. A flexible microwave catheter comprising:

a catheter hub;

an outer sheath extending from the catheter hub, the outer sheath configured to prevent a release of microwave energy therethrough; and

a coaxial feedline disposed within the outer sheath, the coaxial feedline having an inner conductor, an inner dielectric coaxially disposed about the inner conductor, and an outer conductor coaxially disposed about the inner dielectric, wherein the coaxial feedline defines a radiating portion at a distal portion of the coaxial feedline, the radiating portion configured to emit microwave energy; and

wherein the coaxial feedline is slidable within the outer sheath and along a longitudinal axis of the outer sheath such that the radiating portion is selectively deployable from the outer sheath upon distal movement of the coaxial feedline relative to the outer sheath, and wherein the outer sheath includes a first inner diameter along at least a portion of the longitudinal axis and a distal portion of the outer sheath defines a sliding hub having a second inner diameter greater than the first inner diameter.

2. The flexible microwave catheter according to claim 1, wherein a width of the outer conductor of the radiating portion varies according to a longitudinal position thereof along the inner conductor of the radiating portion.

3. The flexible microwave catheter according to claim 1, further comprising a cap operably coupled to a distal end of the inner conductor and the outer conductor and providing an electrical connection therebetween.

4. The flexible microwave catheter according to claim 1, further comprising a temperature sensor disposed at a distal portion of the radiating portion.

5. The flexible microwave catheter according to claim 1, wherein a radiation pattern generated by the radiating portion is related to at least one of a variable width of the outer conductor or a variable helix angle of the outer conductor in the radiating portion.

6. The flexible microwave catheter according to claim 1, wherein the outer conductor in the radiating portion is helically wrapped about the inner conductor in the radiating portion, and wherein the radiating portion further includes a feed gap defined by a void formed between adjacent wraps of the outer conductor.

7. The flexible microwave catheter according to claim 6, wherein a feed gap ratio, defined by the ratio of a feed gap circumference and an outer conductor circumference along a cross section, changes linearly from a proximal end of the outer conductor in the radiating portion to a distal end of the outer conductor in the radiating portion.

8. The flexible microwave catheter according to claim 7, wherein the feed gap ratio varies between 0% at the proximal end of the radiating portion and about 50% at the distal end of the radiating portion.

9. The flexible microwave catheter according to claim 1, further comprising an actuator coupled to the coaxial feedline, the actuator configured to move the coaxial feedline relative to the catheter hub.

10. The flexible microwave catheter according to claim 9, wherein the actuator is configured to move the coaxial feedline relative to the outer sheath.

11. The flexible microwave catheter according to claim 1, wherein the radiating portion further comprises an outer dielectric insulating layer disposed about the outer conductor in the radiating portion, the outer dielectric insulating layer configured to slide along a length of the sliding hub and deploy from the sliding hub.

12. The flexible microwave catheter according to claim 11, wherein an outer surface of the outer dielectric insulating layer is movable along an inner surface of the sliding hub.

13. The flexible microwave catheter according to claim 11, wherein an outer diameter of the outer dielectric insulating layer is greater than the first inner diameter.