Combined angioplasty and intravascular radiotherapy method and apparatus

摘要

Apparatus and methods are provided for relieving a stenosed region of a blood vessel such as a coronary artery using a single catheter that relieves the angioplasty by conventional means and then delivers an easily controllable inherently uniform dosage of radiation to the walls of a blood vessel for preventing restenosis after angioplasty. The apparatus comprises a catheter having an angioplasty balloon surrounded by a second balloon that is inflatable with a liquid containing a suspended radioactive material such as <125>I or <32>P. The catheter is advanced through the patient until this treatment balloon is disposed in the stenosed region of the blood vessel. The stenosed region is relieved using the angioplasty balloon after which the outer balloon is filled with the radioactive fluid which expands the outer balloon to engage the walls of the blood vessel thereby providing an inherently uniform dosage of radiation to the blood vessel walls. An outer containment balloon is also provided to prevent loss of radioactive fluid in the event the treatment balloon ruptures. The angioplasty balloon may be filled during the radiation treatment to minimize the volume of radioactive fluid necessary to achieve the desired dosage. <IMAGE>