Radioactive source wire, apparatus and treatment methods

• Main Authors: BRADSHAW ANTHONY J, RAIZNER ALBERT E, WEINBERG STEVEN L
• Format: Patent
• Language: English
• Published: 14.01.2003
• Edition: 7
• Subjects: BANDAGES, DRESSINGS OR ABSORBENT PADS; DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROMTHE BODY; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF,TUBULAR STRUCTURES OF THE BODY, E.G. STENTS; DIAGNOSIS; ELECTROTHERAPY; FILTERS IMPLANTABLE INTO BLOOD VESSELS; FIRST-AID KITS; FOMENTATION; HUMAN NECESSITIES; HYGIENE; IDENTIFICATION; MAGNETOTHERAPY; MEDICAL OR VETERINARY SCIENCE; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; PROSTHESES; RADIATION THERAPY; SURGERY; TREATMENT OR PROTECTION OF EYES OR EARS; ULTRASOUND THERAPY

A source wire having a radioactive source at its distal tip is used to treat a blood vessel within a patient's body by localized in vivo radiation to prevent stenosis of the blood vessel, including restenosis following percutaneous transluminal coronary angioplasty. The source wire is advanced to the target site along the intravascular system of the patient's body from a point external to the body. The source wire is preferably a solid lead of substantially uniform thickness along its entire length, composed of a superelastic nickel-titanium alloy (nitinol). Alternatively, the wire may be a cable composed of multiple strands of the alloy of substantially uniform thickness throughout the entire length of each strand. The alloy has desired characteristics of superelasticity for transitioning into and out of a stress-induced martensitic state as it is advanced through tortuous lumens for passage into the coronary arteries. The wire also is of a diameter suitable for passage into the coronary arteries, and the distal end of the wire may be tapered for ease of entry into narrowed portions. The targeted tissue is irradiated only briefly, with the radioactive source of the source wire positioned in the lumen of the coronary artery so as to deliver a substantially uniform dosage of radiation to the walls of the lumen.