Abstract: A catheter apparatus and radiation dosimetry unit indicator for delivery of a prescribed radiation dose to a patient. The catheter is filled with a radiation carrier material such as an inert radioactive gas for the treatment of, for example, restenosis after angioplasty, and malignancies. The inflated catheter includes a plurality of discrete chambers for transporting the radioactive carrier material, and a plurality of discrete chambers enabling substantial blood flow through the artery during treatment with the prescribed radiation. The inflated catheter can also comprise a one-unit balloon. A specific metal coating enhances the radiation dose delivered to the target. The wall of the inflation lumen attenuates transmission dose to the blood circulating through the hollow inner lumen of the catheter device. The system also creates increased by-product radiation, from the impact of beta particles and gamma protons traveling toward the lumen wall.

Abstract: An essentially cylindrical, metal-encapsulated, brachytherapy source including an outer metal capsule, an annulus in a central interior position of said outer metal capsule, and a longitudinally extending heavy metal core in said annulus. The annulus is made of the same metal as said outer metal capsule. One or more low-profile welds are formed around the central circumference of the outer metal capsule for attaching the outer metal capsule to the annulus and for sealing the outer metal capsule. A plurality of substrate particles each having bound thereto a radioisotope are positioned in the outer metal capsule so that the radioisotope is distributed symmetrically within the source, equally divided between the two ends of the source, and positioned with a strong bias towards the extremes of the two ends of the source.