摘要 |
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. |