X-ray-emitting interstitial implants
Abstract
Abstract Particles or "seeds" are manufactured for implantation into tumors within a human body for emitting X-rays to destroy or reduce the tumors. The seeds contain palladium which is substantially enriched in palladium-102 and which is activated by exposure to neutron flux so as to contain a minor, but significant, fraction of X-ray-emitting palladium-103. The palladium is distributed on or throughout a base material so as to reduce self-shielding by the palladium. The seeds include an X-ray-opaque marker to facilitate external visualization of the seeds after their implantation, the marker preferably being formed of a material, such as lead or rhodium, which does not activate to contain undesirable isotopes under the radiation conditions in which palladium-102 is activated to palladium-103. The base material-distributed palladium and the marker are encased in an elongated shell which is formed by welding a pair of end caps to a tubular member, the construction of the shell reducing the mass of material at the end of the seed, thereby providing a more isotropic angular distribution of X-rays.
Inventors
- 👤 John L. Russell, Jr.
- 👤 David N. Coggins
Bibliographic Details
Claims Analysis
Total Claims: 10References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1990-10-26 | 1991-04-27 | 1991-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-26 | 1995-04-27 | 1995-10-27 | $3760.00 | Window Closed / Lapsed |
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