X-RAY AND GAMMA RAY EMITTING TEMPORARY HIGH DOSE RATE BRACHYTERAPY SOURCE

摘要

Radioactive sources (10) are manufactured for treating a tumor or cancerous area occurring around a conduit or duct in the body by emitting X-rays to destroy or reduce the tumors. The sources (10) contain ytterbium which is substantially enriched in <168>Ytterbium and which is activated by exposure to neutron flux so as to contain a minor, but significant, fraction of X-ray and gamma-emitting <169>Ytterbium. The radioactive <169>Ytterbium source (10) is inserted through a catheter or applicator or needle to the site of the cancer where it is maintained in position for a period of time to reduce the occurrence of cancer. The ytterbium also acts as an X-ray-opaque marker to facilitate external visualization of the sources during their delivery to the treatment site. The sources are encased in a shell to prevent direct contact of the radioactive material with human tissue. This encapsulation may be formed by welding a pair of end caps (16) to a tubular member (15).