Catheter and spring element for contact force sensing

Patent metadata

Field	Value
Publication number	US-12178662-B2
Application number	US-201815986667-A
Country	US
Kind code	B2
Filing date	May 22, 2018
Priority date	May 23, 2017
Publication date	Dec 31, 2024
Grant date	Dec 31, 2024

Abstract

A spring element for a contact force sensing medical catheter. The spring element includes a first ring, a second ring spaced apart from the first ring, a plurality of struts connecting the first ring to the second ring, and a plurality of interlocking features. The second ring and the first ring are coaxially aligned with a longitudinal axis of the spring element. The plurality of struts is configured to permit elastic, relative axial and radial displacement between the first ring and the second ring. The plurality of interlocking features is configured to limit the relative axial and radial displacement between the first ring and the second ring.

First claim

We claim:

1. A spring element for a contact force sensing medical catheter, the spring element comprising:
a first ring;
a second ring spaced apart from the first ring, the second ring and the first ring coaxially aligned with a longitudinal axis of the spring element; and
a plurality of struts connecting the first ring to the second ring, each of the plurality of struts connected to an adjacent strut by an interconnect configured to define a space between adjacent struts, the plurality of struts configured to elastically deform so as to permit relative axial and radial displacement between the first ring and the second ring;
wherein each of the plurality of struts includes a plurality of interlocking features configured to limit the relative axial and radial displacement between the first ring and the second ring, each of the plurality of interlocking features interlocking with an adjacent strut of the plurality of struts, wherein at least some of the interlocking features include a head portion and a neck portion, the head portion having a first axially facing surface facing away from the neck portion and a second axially facing surface facing a direction opposite the first surface, wherein the first surface and the second surface are substantially parallel to one another.

2. The spring element of claim 1 , wherein each of the plurality of struts extends at least partially in a circumferential direction to permit elastic relative axial and radial displacement between the first ring and the second ring.

3. The spring element of claim 2 , wherein each of the plurality of struts extends at least substantially in the circumferential direction and the plurality of struts are interconnected.

4. The spring element of claim 2 , wherein each of the plurality of struts extends directly between the first ring and the second ring and in both the circumferential direction and an axial direction.

5. The spring element of claim 1 , wherein each of the interlocking features extends between the first ring and one of the plurality of struts adjacent to the first ring, between the second ring and one of the plurality of struts adjacent to the second ring, or between two of the plurality of struts adjacent to each other.

6. The spring element of claim 5 , wherein each of the interlocking features includes:
a tab extending from one of the first ring, the second ring, or the one of the plurality of struts; and
an opening defined in one of the first ring, the second ring, or another one of the plurality of struts adjacent to the one of the first ring, the second ring, or the one of the plurality of struts from which the tab extends, the opening configured to engage the tab.

7. The spring element of claim 6 , wherein for at least some of the interlocking features:
the tab includes the head portion and the neck portion connecting the head portion to the one of the first ring, the second ring, or the one of the plurality of struts, the head portion being wider than the neck portion; and
the opening includes a wide region and a narrow region, wherein the wide region is larger wider in a circumferential direction and longer in an axial direction than the head portion of the tab, the narrow region is wider than the neck portion of the tab, and the narrow region is narrower than the head portion of the tab, the head portion of the tab contained within the wide region and the neck portion of the tab extending through the narrow region such that the opening engages the tab to limit the relative axial and radial displacement between the first ring and the second ring.

8. A spring element for a contact force sensing medical catheter, the spring element comprising:
a first ring;
a second ring spaced apart from the first ring, the second ring and the first ring coaxially aligned with a longitudinal axis of the spring element;
a plurality of struts configured to elastically deform to moveably couple the first ring to the second ring, each of the plurality of struts connected to an adjacent strut by an interconnect configured to define a space between adjacent struts; and
wherein the plurality of struts includes a plurality of interlocking features configured to limit the relative axial and radial displacement between the first ring and the second ring, each of the interlocking features formed in the first ring and engaging one of the plurality of struts adjacent to the first ring, formed in one of the plurality of struts adjacent to the second ring and engaging the second ring, or formed in one of the plurality of struts and engaging a strut adjacent to the one of the plurality of struts, each of the interlocking features including:
a tab including a head portion and a neck portion extending from one of the first ring or the one of the plurality of struts; and
an opening defined in one of the second ring, or another one of the plurality of struts adjacent to the one of the first ring or the one of the plurality of struts from which the tab extends, the opening configured to engage the tab, the opening including a wide region and a narrow region, wherein the wide region contains the head portion and is wider in a circumferential direction and longer in an axial direction than the head portion, wherein the narrow region is wider than the neck portion of the tab, the narrow region is narrower than the head portion of the tab, and wherein the narrow region is defined by two opposing surfaces substantially parallel to the neck portion.

9. A catheter adapted to measure a contact force, the catheter comprising:
a proximal segment;
a distal segment;
a spring segment extending from the proximal segment to the distal segment, the spring segment configured to permit relative displacement between the distal segment and the proximal segment in response to an application of the force on the distal segment, the spring segment including:
a spring element including:
a first ring;
a second ring spaced apart from the first ring, the second ring and the first ring coaxially aligned with a longitudinal axis of the spring element; and
a plurality of struts configured to elastically deform, the plurality of struts elastically coupling the first ring to the second ring and configured to permit elastic, relative axial and radial displacement between the first ring and the second ring;

wherein the plurality of struts includes a plurality of interlocking features configured to limit the relative axial and radial displacement between the first ring and the second ring, wherein each of the plurality of interlocking features is formed in a strut of the plurality of struts and interlocks with an adjacent strut of the plurality of struts;
wherein the plurality of interlocking features includes:
a tab including a head portion and a neck portion connecting the head portion to one of the first ring, the second ring, or one of the plurality of struts, the head portion being wider than the neck portion; and
an opening including a wide region and a narrow region, wherein the wide region is wider in a circumferential direction and longer in an axial direction than the head portion, wherein the narrow region is wider than the neck portion of the tab, the narrow region is narrower than the head portion of the tab, and wherein the narrow region is defined by two opposing surfaces substantially parallel to the neck portion, the head portion of the tab contained within the wide region and the neck portion of the tab extending through the narrow region such that the opening engages the tab to limit the relative axial and radial displacement between the first ring and the second ring; and

a plurality of sensing elements configured to output a plurality of signals indicative of the relative displ

Assignees

• Boston Scient Scimed Inc

Inventors

• Miklos Kimberly A
• Walker Joseph
• Maierhofer Edward J
• Mindermann Garth
• Arnholt Devon N
• College Todd

Classifications

• A61M2025/0002

  with a pressure sensor at the distal end · CPC title

• A61B2018/00577

  Ablation · CPC title

• A61B18/1492

  having a flexible, catheter-like structure, e.g. for heart ablation (A61B18/1477 takes precedence) · CPC title

• A61B2090/065

  for measuring contact or contact pressure · CPC title

• A61B90/37

  Surgical systems with images on a monitor during operation · CPC title