Low-energy brachytherapy sources
OwnerRichard Taschereau, Jean Pouliot +1inventors
InventorsRichard Taschereau, Jean Pouliot, Rene Roy
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Abstract
A radioactive implant characterized by a biological effectiveness comparable to that of palladium-103 and, simultaneously, by a half-life of the order of that of iodine-125. More specifically, the present invention provides a radioactive implant having improved biological effectiveness, by lowering the average energy of the photon spectrum of a relatively long half-life radioisotope element using x-ray fluorescence. Selection of a fluorescent material within elements having an atomic number between 39 and 45, preferably between 40 and 42, for surrounding a radioactive inner core comprising the radioisotope element, is described.
Claims20
A radioactive source capable of radiating energy in a tissue wherein it is to be implanted, comprising:
- a radioactive inner core having an outer surface;
- and
- a layer of fluorescent material disposed around said outer surface;
- wherein said central radioactive inner core comprises at least one radioisotope element and said layer of fluorescent material is made of at least one sub-layer of fluorescent material that has a photon energy lower than the energy of said radioisotope element, so that a substantial portion of the energy of the radioisotope element is shifted within a range that is-effective for preventing cell proliferation of said tissue.
A radioactive source capable of radiating energy, comprising:
- a radioactive central, substantially cylindrical core, comprising iodine-125 and having an outer surface;
- and
- a layer of fluorescent material comprising at least one element selected from niobium, zirconium and molybdenum, and disposed around said outer surface.
A method for fabricating a radioactive source to be implanted in a recipient's tissue, which combines the half-life of a first radioactive element and the energy spectrum of a second radioactive element that has a shorter half-life, comprising the step of shifting down the energy spectrum of the first element towards the energy spectrum of the second radioactive element by placing at least one layer of fluorescent material between the first radioactive element and the tissue to be irradiated.
Dependencies are inferred from the claim text.