Syntheon, LLC

Cns Technology, Inc.

Scott T Smith

Charles R Slater

Scott L Jahrmarkt

Kevin W Smith

Thomas O Bales, Jr

An implantable radiation therapy device includes a biocompatible radiotranslucent outer capsule containing a radiation shielding element and a radioactive isotope at least partially shielded by the shielding element. When the device is at or below body temperature, radiation is prevented or limited from being transmitted through the outer capsule by the shielding element. When non-ambient energy is applied to the device, the shielding element and radioactive isotope are reconfigured such that an increased level of radiation is transmitted through the outer capsule and emitted by the device.

Implantable radiation therapy device having controllable radiation emission

Radioactive therapeutic seeds include a substantially radiotransparent cylindrical capsule containing a radioactive isotope and, in particular embodiments, a radiopaque or MRI-visible marker. Each of the embodiments is designed to provide a substantially isotropic distribution of radiation. In one embodiment, the isotope is deposited on the outer surface of a hollow radiolucent tube and a collar is provided about a central portion of the tube. The capsule comprises two tubular halves positioned over the tube with the open ends of the halves forming an interference fit with the collar and welded thereabout. In another embodiment, the isotope bearing structure is a plurality of radiolucent spheres provided with a thin coating of silver to facilitate the adhesion of the isotope thereto. The spheres are provided in two capsule halves which are welded closed about a plug have an axial radiopaque marker therein. In yet another embodiment, the isotope bearing structure is a pair of silver tubes having surfaces on which the isotope is provided. One tube is positioned in each half of the capsule, and the halves are then welded about a plug provided with a marker. In each embodiment, the closed ends of the capsule are provided with tissue engaging members or connectors which can be coupled to discrete spacing links.

Radioactive therapeutic seeds

Radioactive therapeutic seeds include a substantially radiotransparent cylindrical capsule provided with a radioactive isotope, a radiopaque marker, and an engagement structure adapted to engage tissue surrounding the seeds at the implant site. The engagement structure is also preferably adapted to releasably engage the inside of a delivery needle prior to implantation. The engagement structure is preferably adapted to prevent axial longitudinal movement and axial rotation of a seed about its longitudinal axis when the seed is implanted. According to a preferred embodiment of the invention, the engagement structure includes three spring elements which are biased away from the seed capsule and which provide positive fixation in the tissue, and also frictionally engage the inside of the needle.

Radioactive therapeutic seeds having fixation structure

Radioactive therapeutic seeds include a seed capsule, a radioactive isotope, and a radiopaque marker. According to one embodiment of the invention, the radiopaque marker is a silver wire coil and the isotope is coated on the surface of the coil. According to a first method of the invention, the therapeutic dosage of the seed is adjusted during manufacture by expanding or contracting the coil before it sized and deposited in the capsule. According to second embodiment, the radiopaque marker is a silver rod and the isotope is coated on a radiotransparent coil which is placed over the rod. According to a third embodiment, the isotope is coated on a plurality of rings which are stacked on a radiopaque rod. According to a second method of the invention, the therapeutic dosage of the seed is adjusted during manufacture by stacking a mixture of radio-inactive rings with radioactive rings on the radiopaque rod before the capsule is sealed.

Radioactive therapeutic seeds and methods of making the same

Radioactive therapeutic seeds include a substantially cylindrical capsule containing a radioactive isotope and, preferably, a radiopaque marker. According to one embodiment, the capsule is made of titanium or stainless steel, the isotope is deposited on the surface of a hollow cylinder and a titanium or stainless steel tube is disposed inside the hollow cylinder. The capsule is sealed by swaging the end of the capsule against the inner tube and welding the swaged end and tube. The inner tube facilitates swaging and protects the contents of the capsule from the heat of welding. In alternate embodiments, a radiopaque marker is disposed inside the inner tube or the cylinder bearing the radioisotope is radiopaque. According to other embodiments, a gripping stem is installed on one or both ends of a capsule, a capsule is made of very thin material with rotary swaged ends welded shut and a supporting structure inside the capsule, a meltable isotope mixture is used to coat the interior of a capsule, a capsule is assembled from two halves which are placed over an interior tube and the halves are butt welded, a capsule is made of a borosilicate or elemental silicon glass tube with ends melted to seal the capsule. Bioabsorbable spacers are provided for use with seeds having gripping/linking stems so that seeds are linked together.

An implantable brachytherapy device includes a biocompatible outer capsule containing a radiation shielding element and a radioactive isotope between the shielding element and the wall of the outer capsule. When the device is at body temperature, radiation is emitted by the isotope through the wall of the outer capsule. When a predetermined amount of energy is applied to the device, the shielding element is adapted to at least partially surround the isotope, and thereby at least partially prevent the transmission of radiation through the outer capsule.

Implantable brachytherapy device having at least partial deactivation

Radioactive therapeutic seeds include a two part seed capsule, a radioactive isotope, and, preferably, a radiopaque marker. According to the invention, the seed capsule has an outer part, and an inner part which fits into the outer part and which carries the radioactive isotope. The capsule is sealed by welding the end(s) of the inner part to the end(s) of the outer part. According to one embodiment, the outer part of the seed capsule is a cylinder with one open end and one closed end. The inner part of the seed capsule has a reduced diameter portion which carries the isotope and a larger diameter portion which mates with the open end of the cylinder. According to another embodiment, the outer part of the seed capsule is a cylinder with two open ends. The inner part has a reduced diameter portion which carries the isotope and two larger diameter portions which mate with the open ends of the cylinder. According to some embodiments of the invention, the isotope is carried on a radiopaque structure which is mounted on the reduced diameter portion of the inner part of the seed capsule. According to another embodiment, the inner part of the seed capsule is a hollow member. According to another embodiment, the inner part of the seed capsule is made of radiopaque material.

Growing community of inventors

Miami, FL, United States of America

Scott T Smith