Hydrophilic stent

• US 5,234,456 A
• Filed: 05/07/1992
• Issued: 08/10/1993
• Est. Priority Date: 02/08/1990
• Status: Expired due to Term

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Pfizer Hospital Products Group, Inc. (Pfizer Inc.)
• Inventors: Silvestrini, Thomas A.
• Primary Examiner(s): Rosenbaum, C. Fred
• Assistant Examiner(s): MCDERMOTT, CORRINE MARIE
• Application Number:
  US07/883,241
• Time in Patent Office: 460 Days
• Field of Search: 604/8, 604/96, 604/101, 604/264, 604/265, 604/280, 604/281, 604/285, 606/192, 606/194, 606/198, 606/108, 623/1, 623/12
• US Class Current: 623/1.2
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2002/825 having longitudinal struts
• CPC Class Codes: A61F 2250/0003 having an inflatable pocket filled with fluid, e.g. liquid or gas
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61M 25/1002 characterised by balloon shape A61M25/1006, A61M25/1009 take precedence

Abstract

A stent for placement within a body lumen and comprising a wall structure wherein at least a portion thereof is a hollow wall. The hollow wall has disposed therein a hydrophilic material which can be in the form of a gel, for example, which swells upon introduction of a liquid into the hollow wall to thereby achieve inflation thereof. The hollow wall is fabricated of a semi-permeable membrane whereby fluid from tissues surrounding the stent at the site of placement can pass through the membrane and swell the hydrophilic material to thereby inflate the hollow wall. A drug can be disposed with the hydrophilic material for release through the membrane at the site of stent placement. The entire wall structure of the stent can be a hollow wall, or the wall structure can incorporate both hollow and non-hollow wall portions such as hollow and solid fibers which are braided, woven or wound together.

Claims

1. A stent for placement within a body lumen. The stent comprising a wall structure wherein at least a portion thereof is a closed hollow wall having a plurality of radial openings therethrough, fabricated from a semi-permeable membrane, and wherein the hollow wall has disposed therein a hydrophilic material capable of absorbing a liquid to thereby increase the volume of said material.

2. A stent as claimed in claim 1 wherein the hydrophilic material is a gel.

3. A stent as claimed in claim 1 wherein the configuration thereof is tubular.

4. A stent as claimed in claim 3 wherein the stent is a balloon.

5. A stent as claimed in claim 1 wherein the hydrophilic material has disposed therewith a drug.

6. A stent for placement within a body lumen, the stent comprising a wall structure wherein at least a portion thereof is a hollow wall fabricated from hollow closed fibers which are constructed of semi-permeable membranes and held together by being braided, woven or wound together, and wherein the hollow fibers have disposed therein a hydrophilic material capable of absorbing a liquid to thereby increase the volume of said material.

7. A stent as claimed in claim 6 wherein the hydrophilic material is a gel.

8. A stent as claimed in claim 6 wherein the hydrophilic material has disposed therewith a drug.

9. A stent for placement within a body lumen, the stent having a spiral configuration when inflated and comprising a wall structure wherein at least a portion thereof is a closed hollow wall, fabricated from a semi-permeable membrane, and wherein the hollow wall has disposed therein a hydrophilic material capable of absorbing a liquid to thereby increase the volume of said material.

10. A stent as claimed in claim 9 wherein the hydrophilic material has disposed therewith a drug.

11. A stent as claimed in claim 9 wherein at least a portion of the hollow wall is reinforced.

12. A stent as claimed in claim 9 wherein the stent is a balloon.