Thermo-mechanically controlled implants and methods of use

• US 8,980,297 B2
• Filed: 09/28/2010
• Issued: 03/17/2015
• Est. Priority Date: 02/20/2007
• Status: Active Grant

• Current Assignee: JW Medical Systems Ltd
• Original Assignee: JW Medical Systems Ltd
• Inventors: Ruane, Patrick H., Wilson, Cameron L.
• Primary Examiner(s): Long, Scott
• Assistant Examiner(s): BECKHARDT, LYNDSEY MARIE
• Application Number:
  US12/892,553
• Publication Number:
  US 20110022148A1
• Time in Patent Office: 1,631 Days
• Field of Search: None
• US Class Current: 424/423
• CPC Class Codes: A61F 2/12 Mammary prostheses and implants
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2210/0071 thermoplastic
• CPC Class Codes: A61F 2250/0001 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61F 2250/0004 adjustable
• CPC Class Codes: A61F 2250/0012 for adjusting elasticity, flexibility, spring rate or mechanical tension
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61K 41/0028 Disruption, e.g. by heat or ultrasounds, sonophysical or sonochemical activation, e.g. thermosensitive or heat-sensitive liposomes, disruption of calculi with a medicinal preparation and ultrasounds
• CPC Class Codes: A61L 2430/04 for mammary reconstruction
• CPC Class Codes: A61L 27/44 having a macromolecular matrix
• CPC Class Codes: A61L 27/54 Biologically active materials, e.g. therapeutic substances A61L27/227 takes precedence
• CPC Class Codes: A61L 27/58 Materials at least partially resorbable by the body
• CPC Class Codes: A61L 31/128 containing other specific inorganic fillers not covered by A61L31/126 or A61L31/127
• CPC Class Codes: A61L 31/148 Materials at least partially resorbable by the body
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G21K 5/02 having no beam-forming means

Abstract

An implant comprises a structure that may be implanted into tissue and that has a first material property at normal body temperature. The first material property is variable at elevated temperatures above normal body temperature. The implant also has a plurality of particles dispersed in the structure that are adapted to convert incident radiation into heat energy when irradiated with electromagnetic radiation. The particles are in thermal contact with the structure such that exposure of the particles to incident radiation raises the temperature of the structure thereby changing the first material property relative to the first material property at normal body temperature.

Claims

1. A method of controlling a material property of a stent, the method comprising:

providing a polymeric stent having a plurality of metallic nanoshells dispersed therein, wherein the nanoshells are covered with a metal selected from the group consisting of palladium, silver, platinum, and gold, and wherein the stent has a first material property when implanted in tissue at normal body temperature, the material property being variable at an elevated temperature above normal body temperature; and

exposing the stent to electromagnetic radiation in the range of about 800 nm to 1200 nm, the incident radiation being converted into heat energy via the plurality of nanoshells thus uniformly raising the temperature of the stent above normal body temperature, thereby changing the material property relative to the first material property wherein the material property is either;

(i) the ability of the stent to be plastically deformed such that the stent is not plastically deformable at normal body temperatures but is plastically deformable at an elevated temperature above normal body temperature or

(ii) the viscosity of the stent where the stent has a lower viscosity at an elevated temperature above normal body temperature.

2. The method of claim 1, wherein the stent temperature is raised to a temperature In the range from about 38°

C. to about 60°

C.

3. The method of claim 1, wherein exposing the stent to electromagnetic radiation comprises delivering electromagnetic radiation to the stent with a catheter.

4. The method of claim 1, wherein exposing the stent to electromagnetic radiation comprises delivering the radiation until a desired temperature is obtained in the implant.

5. The method of claim 1, wherein the stent is biodegradable.

6. The method of claim 1, further comprising releasing a therapeutic agent from the stent in a controlled manner.

7. The method of claim 1, wherein the metallic nanoshells are covered with gold.

8. The method of claim 1, further comprising generating the electromagnetic radiation with a laser light source.