Medical device for delivering localized radiation

• US 6,106,454 A
• Filed: 06/17/1997
• Issued: 08/22/2000
• Est. Priority Date: 06/17/1997
• Status: Expired due to Fees

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Berg, Eric P., Dinh, Thomas Q.
• Primary Examiner(s): Gilbert, Samuel G.
• Application Number:
  US08/877,426
• Time in Patent Office: 1,162 Days
• Field of Search: 600/1-8, 376/156
• US Class Current: 600/3
• CPC Class Codes: A61N 5/1002 Intraluminal radiation therapy

Abstract

A medical device useful for localized delivery of radiation in vivo is provided. The medical device includes a structure including a porous material; and a plurality of discrete particles including a water-insoluble radioactive salt dispersed throughout a substantial portion of the porous material. The water-insoluble radioactive salt is formed by contacting an aqueous radioactive salt solution with a heavy metal water-soluble salt dispersed throughout a substantial portion of the porous material. The heavy metal water-soluble salt can be dispersed in the porous material so that the device can be sterilized and the radioactive material can be loaded in the device in situ, for example, just prior to implantation.

Claims

1. An implantable device capable of delivering localized radiation in vivo comprising:

a structure comprising a porous material; and

a plurality of discrete particles comprising a heavy metal water-soluble salt dispersed throughout a substantial portion of the porous material, wherein the heavy metal water-soluble salt forms a water insoluble salt containing a radiation emitting material upon contact with a solution of a radioactive salt.

2. The implantable device of claim 1, wherein the porous material comprises a material selected from selected from the group of a natural hydrogel, a synthetic hydrogel, teflon, silicone, polyurethane, polysulfone, cellulose, polyethylene, polypropylene, polyamide, polyester, and polytetrafluoroethylene.

3. The implantable device of claim 1, wherein the radiation emitting material comprises a β

-radiation emitting isotope.

4. The implantable device of claim 1, wherein the heavy metal water-soluble salt is selected from the group of AgNO₃, Ba(NO₃)₂, BaCl₂, and CaCl₂.

5. The implantable device of claim 1, wherein the structure comprises a generally cylindrical shape.

6. The implantable device of claim 5, wherein the shape is selected from the group of a catheter, a stent, and a guide wire.

7. The implantable device of claim 1, wherein the β

-radiation emitting isotope has an half-life of about 150 days or less.

8. The implantable device of claim 7, wherein the water-insoluble radioactive salt is selected from the group of AgI¹³⁵, BaS³⁵ O₄, and (Ca)₃ (P³² O₄)₂.