Stent retention element and related methods

• US 20030181842A1
• Filed: 03/19/2002
• Published: 09/25/2003
• Est. Priority Date: 03/19/2002
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Gellman, Barry N.
• Granted Patent: US 8,328,877 B2
• Time in Patent Office: Days
• US Class Current: 604/8
• CPC Class Codes: A61F 2002/048 Ureters
• CPC Class Codes: A61M 27/008 pre-shaped, for use in the urethral or ureteral tract

Abstract

In one embodiment, the invention is directed to a stent retention element having an elastic member adapted to be incorporated with a first end of an elongate stent and to coil toward a second end of the elongate stent to anchor the elongate stent at an anatomical site. According to one feature, the stent retention element expands and compresses to effectively lengthen and shorten, respectively, the stent to accommodate ureter lengthening and shortening.

Claims

1. A stent comprising,

an elongate body having first and second ends and defining an internal lumen extending there between, and having a length at least sufficient to extend through an anatomical lumen of a patient from a first anatomical site to a second anatomical site, and

a first retention element incorporated with the first end of the elongate body and including a first elastic member coiling toward the second end of the elongate body at first distances around a first section of the elongate body and adapted to anchor the stent at the first anatomical site.

2. The stent of claim 1, wherein the first retention element includes a first elongate section extending axially from the first end of the elongate body and the first elastic member coils toward the second end of the elongate body at first distances around the first elongate section of the first retention element.

3. The stent of claim 1 further comprising,

a second retention element incorporated with the second end of the elongate body and including a second elastic member coiling toward the first end of the elongate body and adapted to anchor the stent at the second anatomical site.

4. The stent of claim 3, wherein the second elastic member coils toward the first end of the elongate body at second distances around a second section of the elongate body.

5. The stent of claim 3, wherein the second retention element includes a second elongate section extending axially from the second end of the elongate body and the second elastic member coils toward the first end of the elongate body at second distances around the second elongate section of the second retention element.

6. The stent of claim 1, wherein the first elastic member is adapted to compress in response to an axial force directed from the second end toward the first end of the elongate body, the compression retracting a portion of the elongate body from the ureter to accommodate ureter shortening.

7. The stent of claim 6, wherein the first retention element is adapted to return to an uncompressed steady state in response to removal of the axial force to re-extend the portion of the elongate body back into the ureter to accommodate ureter re-lengthening.

8. The stent of claim 1, wherein the first retention element is adapted to expand in response to an axial force directed from the first end toward the second end of the elongate body to extend a portion of at least one of the elongate body and the first retention element into the ureter to accommodate ureter lengthening.

9. The stent of claim 8, wherein the first retention element is adapted to return to an unexpanded state in response to removal of the axial force to retract the portion of the elongate body or retention element from the ureter to accommodate ureter re-shortening.

10. The stent of claim 1, wherein the first distances are substantially constant to form the first retention element as a substantially cylindrical helix having a plurality of coils having substantially equal diameters.

11. The stent of claim 1, wherein the first distances are substantially constant to form the first retention element as a substantially cylindrical helix having a plurality of coils having substantially equal diameters.

12. The stent of claim 1, wherein the first distances vary to form the first retention element as a conical spiral having a plurality of coils, each having an associated diameter, the associated diameter increasing as the plurality of coils extends from the first end toward the second end of the elongate body.

13. The stent of claim 1, wherein the first distances vary to form the first retention element as a conical spiral having a plurality of coils, each having an associated diameter, the associated diameter increasing as the plurality of coils extends from the first end toward the second end of the elongate body.

14. The stent of claim 12, wherein those of the plurality of coils having a relatively smaller diameter are adapted to pass through those of the plurality of coils having a relatively larger diameter in response to an axial force on the first retention element directed from the first end toward the second end of the elongate body.

15. The stent of claim 13, wherein those of the plurality of coils having a relatively smaller diameter are adapted to pass through those of the plurality of coils having a relatively larger diameter in response to an axial force on the first retention element directed from the first end toward the second end of the elongate body.

16. The stent of claim 1, wherein the first retention element defines an internal retention element lumen.

17. The stent of claim 16, wherein the first retention element is adapted to uncoil in response to inserting a guide wire into the internal retention element lumen.

18. A stent retention element comprising, an elastic member adapted to be incorporated with a first end of an elongate stent and to coil toward a second end of the elongate stent to anchor the elongate stent at an anatomical site.

19. The stent retention element of claim 18, wherein the elastic member is adapted to coil toward the second end of the elongate stent at first distances around a first section of the elongate stent.

20. The stent retention element of claim 19, wherein the retention element includes an elongate section adapted to extend axially from the first end of the elongate body, and the elastic member is adapted to coil toward the second end of the elongate stent at first distances around the elongate section of the stent retention element.

21. The stent retention element of claim 19, wherein the first distances are substantially constant to form the elastic member as a substantially cylindrical helix having a plurality of coils with substantially equal diameters.

22. The stent retention element of claim 20, wherein the first distances are substantially constant to form the elastic member as a substantially cylindrical helix having a plurality of coils with substantially equal diameters.

23. The stent retention element of claim 19, wherein the first distances vary to form the elastic member as a conical spiral having a plurality of coils, each of the plurality of coils having an associated diameter, and the associated diameter increasing as the plurality of coils extend toward the second end of the elongate stent.

24. The stent retention element of claim 20, wherein the first distances vary to form the elastic member as a conical spiral having a plurality of coils, each of the plurality of coils having an associated diameter, and the associated diameter increasing as the plurality of coils extend toward the second end of the elongate stent.

25. The stent retention element of claim 23, wherein those of the plurality of coils having a relatively smaller diameter are adapted to pass through each of the plurality of coils having a relatively larger diameter in response to an axial force directed from the first end toward the second end of the elongate stent.

26. The stent retention element of claim 24, wherein those of the plurality of coils having a relatively smaller diameter are adapted to pass through each of the plurality of coils having a relatively larger diameter in response to an axial force directed from the first end toward the second end of the elongate stent.

27. The stent retention element of claim 18, wherein the elastic member defines a retention element lumen.