Abstract: An implantable source (40) of therapeutic radiation for brachytherapy is provided as a sealed, biocompatible capsule (410) of plastic (e.g. polyethylene or PEEK) transparent to the radiation. The capsule contains a radiation source (400) comprising particles of a radioactive isotope (e.g. Pd103, I125, Cs131) in a fluid carrier that is resistant to radiation polymerization but solidifies at elevated temperature. It also has a marker (420), and desirably has a socket (430) which accommodates attaching spacers (660) and makes possible linear strands and planar arrays of the capsules. The spacers may be functional, e.g. heat-generating or medication-releasing.

Abstract: An implantable source (40) of therapeutic radiation for brachytherapy is provided as a sealed, biocompatible capsule (410) of plastic (e.g. polyethylene or PEEK) transparent to the radiation. The capsule contains a radiation source (400) comprising particles of a radioactive isotope (e.g. Pd103, I125, Cs131) in a fluid carrier that is resistant to radiation polymerization but solidifies at elevated temperature. It also has a marker (420), and desirably has a socket (430) which accommodates attaching spacers (660) and makes possible linear strands and planar arrays of the capsules. The spacers may be functional, e.g. heat-generating or medication-releasing.

Abstract: Therapeutic sources for use in the practice of brachytherapy comprise a radioactive composite that includes (a) a polymeric matrix and (b) a radioactive powder, e.g. Pd-103 or I-125, consisting essentially of very fine radioactive particles that are randomly and essentially uniformly dispersed within the polymeric matrix. The composite may be in the shape of one or more solid cylindrical rods surrounded by a non-radioactive sleeve. Alternatively it may be a hollow rod, suture, film, sheet, or microspheroidal particles. The composite may be shaped by molding, extrusion or other methods, may be made with a flexibility suitable to its intended use or may be encapsulated in a metallic capsule.

Abstract: Therapeutic sources for use in the practice of brachytherapy are fabricated from radioactive composites of a radioactive powder of palladium-103, yttrium-90, phosphorus-32 or gold-198 and a biocompatible polymeric matrix. The particles of radioactive powder are dispersed within the polymer essentially randomly throughout a particular volume. The polymeric matrix is desirably manufactured with preselected flexibility suitable to its intended use, e.g. in the form of a rod, hollow rod, suture, film, sheet, or microspheroidal particles. The radioactive composites produce therapeutic sources which generate a radiation field that is substantially uniform in all directions. The therapeutic source may assembled from the radioactive composite during a medical procedure to emit the desired amount of therapeutic radiation. Optionally, the polymer is selected to dissolve or degrade in the body at a predetermined rate, the rate chosen depending upon the half life of the radioisotope used in the therapeutic source.

Abstract: A method and apparatus for precisely applying radioactive material to a substrate such as a brachytherapy device is disclosed. A radioactive fluid adapted to cure rapidly is deposited as discrete dots onto a surface with a fluid-jet printhead. The apparatus comprises a fluid-jet printhead in communication with a chamber containing radioactive fluid to be applied by the printhead. The printhead is microprocessor driven, and the microprocessor may be provided with feedback from a station where the radioactivity deposited on a preceding substrate in a batch is measured, permitting the system to be recalibrated on an ongoing basis as the batch of printed devices is produced. Compensation for attenuation of radiation by a casing may also be made part of the feedback technique. Also disclosed is a brachytherapy device having printed on a surface dots of radiation-emitting material, in a pattern comprising various bands, dots or areas.

Abstract: A method of making a sealed double-walled tubular precursor device that is adapted to be transmuted into a brachytherapy device is disclosed. The device is hollow-tube-shaped, allowing the easy association of the device with suture material. Disclosed are methods of making devices that can be rendered radioactive by the transmuting effects of irradiation by a cyclotron or nuclear reactor. The brachytherapy devices facilitate medical application and improve safety for patients and medical personnel.

Abstract: A method of making a novel brachytherapy device is disclosed. The device is formed from a hollow-tube-shaped seed-substrate, allowing the easy association of the device with suture material. This shape minimizes the chance of migration of implanted seeds due to better attachment to tissue. The distribution of the radioactive material on the exterior surface of an interior tube of the tubular device provides a relatively uniform radiation field around the hollow-tube-shaped brachytherapy seed source. Methods are disclosed of making brachytherapy devices that are inherently radioactive. Also disclosed are methods of making devices that can be rendered radioactive by the transmuting effects of neutron irradiation. Brachytherapy devices are disclosed that facilitate medical application and improve safety for patients and medical personnel.

Abstract: A method and apparatus for precisely applying radioactive material to a substrate such as a brachytherapy device is disclosed. A radioactive fluid adapted to cure rapidly is deposited as discrete dots onto a surface with a fluid-jet printhead. The apparatus comprises a fluid-jet printhead in communication with a chamber containing radioactive fluid to be applied by the printhead. The printhead is microprocessor driven, and the microprocessor may be provided with feedback from a station where the radioactivity deposited on a preceding substrate in a batch is measured, permitting the system to be recalibrated on an ongoing basis as the batch of printed devices is produced. Compensation for attenuation of radiation by a casing may also be made part of the feedback technique. Also disclosed is a brachytherapy device having printed on a surface dots of radiation-emitting material, in a pattern comprising various bands, dots or areas.

Abstract: A novel brachytherapy device is formed from a hollow-tube-shaped seed-substrate, allowing the easy association of the device with suture material. This shape minimizes the chance of migration of implanted seeds due to better attachment to tissue. The distribution of the radioactive material on the exterior surface of the tubular device provides a relatively uniform radiation field around the hollow-tube-shaped brachytherapy seed source. Brachytherapy devices are described that are inherently radioactive. Also disclosed are devices that can be rendered radioactive by the transmuting effects of neutron irradiation. Brachytherapy devices are discussed that facilitate medical application and improve safety for patients and medical personnel.