Carrier system and method for delivering directed radiation therapy to a tissue site in response to a dosimetry plan - Patents.com

Abstract

The present disclosure is directed to devices for use in radiation therapy. For example, various configurations of shielding material in a shielding layer are contemplated herein for use in shielding radiation from a radioactive source in an implanted radioactive carrier.

Description

[Technical field]

[0001] The present disclosure relates generally to devices used in conjunction with radiation therapy. [Background technology]

[0002] Living tumors vary widely in size, location, and amount of infiltration into normal tissue, and this variability generally makes a one-size-fits-all approach to treatment very difficult. Furthermore, the extent of tumor and / or cavity at the time of debulking is usually unknown until presented in the operating room. Thus, the options required to effectively treat a tumor or tumor bed must be quite diverse.

[0003] Brachytherapy involves placing a radiation source within or immediately adjacent to a tumor. It provides effective treatment of cancers in many body sites. Brachytherapy provides cost-effective treatment as part of multi-modality cancer care. Brachytherapy may be intracavitary, such as when treating gynecological malignancies; intraluminal, such as when treating esophageal or lung cancer; superficial, such as when treating skin cancer; or interstitial, such as when treating various central nervous system tumors, and extracranial tumors of the head and neck, lung, soft tissue, gynecological sites, rectum, liver, prostate, penis, and skin. Summary of the Invention

[0004] Various embodiments of the systems, methods, and devices within the scope of the appended claims each have several aspects, none of which may share all of the desirable attributes described herein, and without limiting the scope of the appended claims, the following description will set forth some of the more prominent features.

[0005] In some aspects, the technology described herein relates to an encapsulated radioactive seed comprising a shielded encapsulant having a substantially cylindrical shaped device having a shielding layer comprising a high-z material embedded therein, wherein the shielded encapsulant comprises a central longitudinal cavity and a longitudinal opening into the cavity, wherein a substantially cylindrical radioactive seed is positioned within the central longitudinal cavity, wherein the longitudinal opening is sized to permit movement of the radioactive seed within the central longitudinal cavity having an inner diameter substantially the same as an outer diameter of the radioactive seed, wherein the shielding layer within the shielded encapsulant is configured to shield radiation emitted from the radioactive seed.

[0006] In some embodiments, the technology described herein relates to a shielding device having a shielding layer comprising a high-z material configured to shield radiation emitted from a radiation source; where the shielding device is configured to be attached to the radiation source by a snap fit or a friction fit to cover at least a portion of an outer surface of the radiation source; where when the shielding device is attached to the radiation source, the shielding layer is configured to shield radiation emitted from the radiation source.

[0007] In some aspects, the technology described herein relates to a shielding device, where the shielding device is cylindrical in shape having a hollow interior region and the radiation source is substantially cylindrical, whereby the shielding device receives the cylindrical radiation source in the hollow interior region.

[0008] In some aspects, the technology described herein relates to a shielding device that further includes one or more protrusions configured to increase the rotational inertia of the shielding device and prevent the shielding device from rotating relative to a carrier on which the shielding device is disposed.

[0009] In some embodiments, the technology described herein relates to a shielding device, wherein one or more protrusions are visible from the exterior of the carrier in which the shielding device is disposed to indicate the direction in which radiation emitted from a radiation source is shielded by the shielding layer.

[0010] In some aspects, the technology described herein relates to a shielding device, where the shielding layer comprises electroplated gold or tantalum.

[0011] In some aspects, the technology described herein relates to a shielding device, where the shielding layer comprises multiple individual, distinct layers of one or more high-Z materials.

[0012] In some aspects, the technology described herein relates to a shielding device, where a shielding layer is embedded in an interior area of ​​the shielding device.

[0013] In some aspects, the technology described herein relates to a shielding device, where a shielding layer is positioned on an exterior surface of the shielding device.

[0014] In some embodiments, the technology described herein relates to a shielding device, where the shielding layer has two half value layers (HVLs).

[0015] In some embodiments, the technology described herein relates to a shielding device, where the shielding layer is configured to reduce the magnitude of radiation traveling from a radiation source by a factor of four in the direction of the shielding layer.

[0016] In some embodiments, the technology described herein relates to a shielding device further having a cap at an end of the shielding device, where the cap comprises a high-Z material configured to shield radiation emitted by the radiation source in the direction of the cap.

[0017] In some aspects, the technology described herein relates to a shielding device, wherein the shielding device is cylindrically shaped with a hollow interior region and configured to receive a cylindrical radiation source in the hollow interior region, wherein the shielding device has a thickness between about 0.18 mm and 0.22 mm, and the shielding layer has a thickness between about 0.026 mm and 0.036 mm. In some embodiments, the shielding layer has a thickness between about 0.01 mm and 0.06 mm.

[0018] In some aspects, the technology described herein relates to a shielding device, where the shielding device comprises a plastic or a polymer.

[0019] In some aspects, the technology described herein relates to a carrier system for delivering directed radiation therapy to a tissue site in response to a dosimetry plan, the carrier system including: a carrier configured to hold one or more radioactive seeds, where the carrier comprises a biocompatible material; a plurality of shielding devices secured to the radioactive seeds and configured to shield a portion of radiation emitted from the radioactive seeds, where each of the plurality of shielding devices partially surrounds a corresponding radioactive seed to provide radiation shielding; where a shielding device is secured to a corresponding radioactive seed to position a shielding layer relative to the radioactive seed and carrier to shield a portion of the radiation emitted from the radioactive seed in a direction relative to the carrier; and one or more connectors secured to the plurality of shielding devices and configured to linearly connect the shielding devices.

[0020] In some aspects, the technology described herein relates to a system, where the radioactive seeds and shielding device are entirely embedded within a carrier.

[0021] In some aspects, the technology described herein relates to a system, where the radioactive seeds are embedded entirely within a carrier, and where the shielding device is configured to be secured to an exterior surface of the carrier.

[0022] In some aspects, the technology described herein relates to a system, where a plurality of shielding devices include protrusions configured to penetrate the carrier and secure the shielding devices to the carrier.

[0023] In some aspects, the technology described herein relates to a system, where a plurality of shielding devices include one or more protrusions configured to increase rotational inertia to reduce rotation relative to the carrier.

[0024] In some embodiments, the technology described herein relates to a system, where one or more protrusions are visible from the exterior of the carrier to indicate the direction in which radiation emitted from the radioactive seeds is blocked by the shielding layer.

[0025] In some aspects, the technology described herein relates to a system, where the shielding layer comprises electroplated gold or tantalum.

[0026] In some aspects, the technology described herein relates to a system, where the shielding layer comprises multiple individual, distinct layers of one or more high-Z materials.

[0027] In some aspects, the technology described herein relates to a system, where a shielding layer is embedded in an interior area of ​​a shielding device.

[0028] In some aspects, the technology described herein relates to a system, where a shielding layer is positioned on an exterior surface of a shielding device.

[0029] In some embodiments, the technology described herein relates to a system, where the shielding layer has two half value layers (HVLs).

[0030] In some embodiments, the technology described herein relates to a system, where a shielding layer is configured to reduce the magnitude of radiation traveling from a radioactive seed by a factor of four in the direction of the shielding layer.

[0031] In some embodiments, the technology described herein relates to a system further having a cap at an end of the shielding device, where the cap comprises a high-Z material configured to block radiation emitted by the radiation source in the direction of the cap.

[0032] In some aspects, the technology described herein relates to a system, wherein one or more connectors are cylindrical in shape and have a diameter of 0.5 mm.

[0033] In some aspects, the technology described herein relates to a system, where one or more connectors are configured to flex and to withstand compressive and torsional forces to prevent stretching, compression, and twisting.

[0034] In some aspects, the technology described herein relates to a system, where one or more connectors include ribs to facilitate bending of the connector.

[0035] In some aspects, the technology described herein relates to a system, where one or more connectors include a sensor.

[0036] In some aspects, the technology described herein relates to a system, where one or more connectors comprise a therapeutic agent.

[0037] In some aspects, the technology described herein relates to a system, wherein one or more connectors comprise a high-Z material.

[0038] In some aspects, the technology described herein relates to a carrier system, where at least one of the one or more connectors includes one or more protrusions visible from the exterior of the carrier to indicate a direction in which radiation emitted from the radioactive seeds is shielded by the shielding layer.

[0039] In some aspects, the technology described herein relates to a carrier system, where an end of at least one of the plurality of shielding devices is flush with a surface of the carrier.

[0040] In some aspects, the technology described herein relates to a carrier system, where at least one end of the one or more connectors is flush with a surface of the carrier.

[0041] In some aspects, the technology described herein relates to a system, wherein the carrier comprises collagen.

[0042] In some embodiments, the technology described herein relates to a shielding device comprising: a shielding layer comprising a high-z material configured to shield radiation emitted by a radiation source from within the carrier; one or more fasteners protruding from a surface of the shielding device and protruding a depth into the carrier to secure the shielding device to the carrier, wherein the shielding device is configured to be attached to the carrier by the fasteners and cover at least a portion of an outer surface of the carrier; and wherein when the shielding device is attached to the carrier, the shielding layer is configured to shield radiation emitted from a radiation source within the carrier.

[0043] In some aspects, the technology described herein relates to a shielding device, wherein the shielding device is spherical in shape having a hollow interior region, and the carrier is substantially spherical such that the shielding device receives the carrier in the hollow interior region.

[0044] In some aspects, the technology described herein relates to a shielding device, wherein the shielding device is planar and the carrier is substantially rectangular, and wherein the shielding device is configured to be attached to a substantially planar surface of the carrier.

[0045] The details of one or more embodiments of the subject matter described herein are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. It should be noted that the relative dimensions of the following figures may not be to scale. [Brief description of the drawings]

[0046] [Figure 1A] 1 is a cross-sectional view showing a portion of a patient's tissue in which a radioactive carrier has been placed; [Figure 1B] 1 is a cross-sectional view showing a portion of a patient's tissue in which a radioactive carrier has been placed; [Figure 1C] 1 is a cross-sectional view showing a portion of a patient's tissue in which a radioactive carrier has been placed;

[0047] [Figure 2A] FIG. 2 shows a perspective view of a tile-shaped embodied carrier device.

[0048] [Figure 2B] 1 illustrates a cross-sectional view of an exemplary carrier tile.

[0049] [Figure 3A] 1 is a perspective view of an exemplary embodiment of a dressing;

[0050] [Figure 3B] 1 is a perspective view of an exemplary embodiment of an encapsulant having a shielding layer on or around a seed.

[0051] [Figure 3C] 1 is a perspective view of an exemplary embodiment of an encapsulated seed, the encapsulant including a shielding layer.

[0052] [Figure 3D] 1 is a perspective view of an exemplary embodiment of an encapsulated seed, where the encapsulant does not include a shielding layer.

[0053] [Figure 3E] 1 is a perspective view of an exemplary embodiment of an encapsulated seed.

[0054] [Figure 3F] FIG. 1 is a perspective view of an exemplary embodiment of a cylindrically shaped encapsulant in which more than half the circumference of the cylinder (e.g., more than 180 degrees) remains in place around the cavity portion to retain the seed with a snap fit.

[0055] [Figure 3G] FIG. 1 is a perspective view of an exemplary embodiment of an encapsulated seed, in which the seed is snap-fitted into the encapsulant.

[0056] [Figure 4A] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant on or around a seed. [Figure 4B] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant on or around a seed. [Figure 4C] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant on or around a seed. [Figure 4D] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant on or around a seed. [Figure 4E] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant on or around a seed. [Figure 4F] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant on or around a seed.

[0057] [Figure 5A] 1 is an end view of an exemplary embodiment of an encapsulant on or around a seed. [Figure 5B] 1 is an end view of an exemplary embodiment of an encapsulant on or around a seed. [Figure 5C] 1 is an end view of an exemplary embodiment of an encapsulant on or around a seed.

[0058] [Figure 6A] 1 illustrates an exemplary implementation of an encapsulant and seeds within a carrier. [Figure 6B] 1 illustrates an exemplary implementation of an encapsulant and seeds within a carrier. [Figure 6C] 1 illustrates an exemplary implementation of an encapsulant and seeds within a carrier. [Figure 6D] 1 illustrates an exemplary implementation of an encapsulant and seeds within a carrier.

[0059] [Figure 6E] 1 illustrates an exemplary embodiment of an encapsulant in contact with various carriers. [Figure 6F] 1 illustrates an exemplary embodiment of an encapsulant in contact with various carriers. [Figure 6G] 1 illustrates an exemplary embodiment of an encapsulant in contact with various carriers.

[0060] [Figure 7A] 1 illustrates an exemplary embodiment of an encapsulant having protrusions. [Figure 7B] 1 illustrates an exemplary embodiment of an encapsulant having protrusions. [Figure 7C] 1 illustrates an exemplary embodiment of an encapsulant having protrusions.

[0061] [Figure 8A] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant connected by a connector. [Figure 8B] 1A-1D are end and cross-sectional views of an exemplary embodiment of an encapsulant connected by a connector.

[0062] [Figure 9A] 1 is an end view of a plurality of exemplary encapsulants having a shielding layer and connected by an exemplary connector. [Figure 9B] 1 is a side view of a plurality of exemplary encapsulants having a shielding layer and connected by an exemplary connector. [Figure 9C] 1 is a top view of a plurality of exemplary encapsulants having a shielding layer and connected by an exemplary connector.

[0063] [Figure 10A] FIG. 2 is a perspective view of an encapsulant and a seed connected by a connector.

[0064] [Figure 10B] 1A-1C are end and cross-sectional views of an exemplary implementation of an encapsulant, seed, and connector within a carrier.

[0065] [Figure 10C] FIG. 2 is a top view of an exemplary encapsulated seed assembly positioned for insertion into the side of a carrier.

[0066] [Figure 11]1 is a perspective view of an exemplary insertion device for placing encapsulants and seeds into a carrier. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0067] overview Tumors are difficult to eradicate surgically because their invasive nature makes them impossible to completely excise microscopically without excessive side effects or mortality. This local persistence of tumor cells may be controlled if sufficient radiation can be safely delivered before the remaining tumor cells regrow and replicate. Debulking surgery followed by radiation therapy may be used to locally control the tumor. For example, various systems, methods, and devices used in conjunction with radiation therapy to deliver (and control delivery of) radiation to the tumor bed after surgery are discussed herein. term

[0068] To facilitate understanding of the systems and methods discussed herein, several terms are explained below. These terms, as well as other terms, as used herein should be interpreted to include the explanations provided, the ordinary and customary meaning of those terms, and / or any other suggested meaning for each term, such interpretation being consistent with the context of those terms. Thus, the following explanations do not limit the meaning of those terms, but provide exemplary explanations only.

[0069] Tumor: An abnormal growth of tissue resulting from the uncontrolled and progressive proliferation of cells. Tumors can be benign or malignant.

[0070] Tumor bed: The anatomical region in a patient (e.g., a human or other mammal) in which a tumor resides (pre-operative tumor bed), and / or the region surrounding a surgically removed tumor (post-operative tumor bed), e.g., the cranial cavity from which a tumor has been surgically removed. Even after surgical removal of a tumor, the patient's remaining tumor bed may contain tumor cells.

[0071] Treatment area: A targeted anatomical region for delivery of radiation from one or more radiation delivery devices (e.g., carriers, discussed below), etc. The treatment area may include tissues under and / or around where the radiation delivery device is located, such as the anatomical region of a tumor or tumor bed.

[0072] Treatment surface: An anatomical surface of a patient (e.g., a human or other mammal) on which a radiation delivery device is to be placed to deliver radiation to a treatment area, such as the treatment surface itself and / or the tissues beneath the treatment surface. The treatment surface may be a portion of a tumor bed or any other anatomical surface. For example, if a tumor bed is surgically created, the treatment surface may include the entire exposed surface of the tumor bed, a portion of such an exposed surface, or the entire exposed surface of the tumor bed as well as surrounding tissue regions.

[0073] Brachytherapy: Radiation therapy in which a radiation delivery device is placed directly on and / or near a treatment surface of the body, e.g., directly on the surface of the body, within the body, or in a tumor bed. For example, brachytherapy may be intracavitary, such as in cranial or gynecological malignancies; intracavitary, such as in esophageal or lung cancer; external, such as in cancer of the skin; and / or intrainterstitial, such as in the treatment of various central nervous system tumors and extracranial tumors of the head, neck, lung, soft tissue, gynecological sites, rectum, liver, prostate, and penis.

[0074] Seed: A radioactive material configured to deliver radiation to a tumor and / or tumor bed. Seeds may be of various shapes and sizes, such as cylinders, cones, spheres, pyramids, cubes, prisms, rectangular prisms, triangular prisms, and / or any combination thereof, or other shapes. Although seeds are generally referred to herein as being cylindrical, seeds of any other shape or size may alternatively be used in the various systems and methods discussed herein. Seeds may include any combination of one or more of multiple radioactive components, such as, for example, Cs131, Ir192, I125, Pd103, etc. Seeds may include a protective shell that partially or completely surrounds the radioactive material. Seeds are one form of radioactive source. As used herein, the term "radioactive source" generally refers to a radioactive seed (or other object that emits radiation), either alone (e.g., a single seed) or embedded or otherwise attached to a carrier (e.g., a tile carrier with embedded radioactive seeds).

[0075] Carrier: a substrate that holds or contains radioactive seeds. A carrier containing one or more seeds is a radiation delivery device. The carrier may include various materials, such as one or more biocompatible and / or bioabsorbable materials, for example collagen. As such, these bioabsorbable materials are biodegradable or naturally absorbed by mammalian tissue over time, such as over a period of weeks or months. The carrier may be configured to be permanently implanted in the tumor bed, such as to provide radiant energy to a treatment surface surrounding the area where the tumor was removed to treat any remaining malignant tissue. The carrier may be composed of various materials and take on various shapes and sizes. Exemplary carriers, such as carriers having various sizes, shapes, and configurations, are included in the following patents and patent applications, each of which is hereby incorporated by reference in its entirety for all purposes: · U.S. Patent Application No. 14 / 322,785, filed July 2, 2014, now U.S. Patent No. 8,876,684, entitled "Dosimetrically Customizable Brachytherapy Carriers and Methods Thereof In The Treatment Of Tumors" U.S. Patent Application No. 14 / 216,723, filed March 17, 2014, now U.S. Patent No. 9,492,683, entitled "Dosimetrically Customizable Brachytherapy Carriers and Methods Thereof In The Treatment Of Tumors"

[0076] Tile Carrier (also called "Tile"): A type of carrier that is substantially planar and generally maintains a two-dimensional planar geometry when placed in a tumor bed. However, depending on the tile material, the tile may be flexible, allowing the tile to deform by bending to better conform to the tumor bed. For example, in the case of tiles that essentially comprise collagen (and / or other flexible materials), the tile may bend substantially when placed in or on (and / or pressed against) a treatment surface to conform to the shape of the treatment surface, such as a post-operative tumor bed.

[0077] Custom Carrier: A carrier having one or more non-planar surfaces, e.g., a spherical shape or having a spherical portion. Examples of custom carriers include the spherical carriers, gore carriers, and star carriers described below, as well as other custom carriers discussed herein.

[0078] Spherical Carrier (or "Gamma Sphere"): A body with substantial radial symmetry about an axis. Spherical carriers may also include non-spherical portions, such as tapered portions extending from a spherical portion. Examples of other variations of spherical carriers are discussed in co-pending Provisional Application No. 63 / 163583, entitled "Custom Brachytherapy Carriers," filed March 19, 2021, which is incorporated by reference in its entirety for all purposes.

[0079] Gore Carrier (also referred to as "Gore"): A type of carrier that is three-dimensional and conforms to the tumor bed while maintaining the necessary geometry for effective implantation. In some embodiments, the gore is initially planar and reconfigures to assume a three-dimensional shape, such as forming a hemispherical surface that can be placed into a similarly shaped tumor cavity. Gore carriers are further discussed in U.S. Patent No. 8,876,684, entitled "Dosimetrically customizable brachytherapy carriers and methods thereof in the treatment of tumors," filed July 2, 2014 as Application Serial No. 14 / 322,785, which is hereby incorporated by reference in its entirety for all purposes.

[0080] Star carriers (also called "stars" or "armed carriers"): a type of carrier that assumes a conformable three-dimensional shape when arranged or positioned in a surgical cavity or similar space to conform to the treatment environment while maintaining the geometry necessary for effective implantation. However, in some embodiments, star carriers may be used in their initial planar state to cover relatively flat tumor or tumor bed areas. Star carriers are further discussed in U.S. Patent No. 9,492,683, entitled "Dosimetrically customizable brachytherapy carriers and methods thereof in the treatment of tumors," filed March 17, 2014 as Application Serial No. 14 / 216,723, which is hereby incorporated by reference in its entirety for all purposes.

[0081] Loader: A device that aids in placing radioactive seeds into a carrier, such as by injecting the seeds into the carrier. A loader, also referred to herein as a "loading device," may have multiple components to hold the carrier in place, guide a delivery device (e.g., a needle or syringe) into the carrier to place the seeds in a precise location in the carrier, etc. "Loader Patents" refers to U.S. Patent Application No. 13 / 460,809, now U.S. Patent No. 8,939,881, filed April 30, 2012, entitled "Apparatus For Loading Dosimetrically Customizable Brachytherapy Carriers," and U.S. Patent Application No. 14 / 696,293, filed April 24, 2015, entitled "Apparatus and Method for Loading Radioactive Seeds Into Carriers," each of which is hereby incorporated by reference in its entirety for all purposes, which describe several embodiments of loaders. As discussed further herein, the loader may be manually operated, such as by a human operator, or may be fully automated such that the carriers are loaded with seeds using an automated process. Alternatively, the loader may be configured to be partially automated and partially requiring manual operation.

[0082] High-Z Material: Any element with an atomic number greater than 20, or an alloy containing such a material.

[0083] Hot Carrier: A carrier loaded with radioactive material.

[0084] Cold Carrier: A carrier that has not been loaded with radioactive material, such as a carrier prior to loading with radioactive seeds.

[0085] Shielding material: any material that limits the movement of radioactive particles, such as by absorbing, reflecting, and / or scattering them. The term "shielding" as used herein generally refers to any mechanism by which a shielding material prevents radiation from passing through and exiting a corresponding shielding material, such as by absorbing, reflecting, or otherwise blocking radiation. In various embodiments discussed herein, various forms of shielding materials may be used. For example, the shielding material may be in the form of particles, wires, rods, cylinders, bars, sheets, liquids, solutions, foams, or any other form that allows the material to have radiation absorbing and / or reflecting properties. Shielding materials generally provide a shielding factor, which is the amount of shielding of radiant energy (emitted from one or more radiation sources) provided by a particular shielding material. Similarly, a shielding layer, including multiple shielding materials and insulating sheets, has an associated shielding factor that varies depending on the combination of shielding (and possibly non-shielding) materials therein. For some applications, e.g., based on clinical need, an insulation sheet providing a shielding rate of 25%, 50%, 75%, 90%, 95%, 98%, or some other shielding percentage may be desired. As discussed herein, material composition, shape, size, dimensions, etc. may affect the shielding capabilities of a shielding material. For applications where a higher shielding percentage is desired than can be provided by a single shielding material (e.g., based on clinical need), multiple shielding materials may be used in combination in one or more shielding layers or insulation sheets.

[0086] In some embodiments, the shielding material includes high-Z materials such as tantalum, gold, platinum, tin, steel, copper, aluminum, etc. (e.g., metal foils with a thickness of 0.01 mm to 0.06 mm). In other embodiments, any other material that reduces radiation penetration may be the shielding material. For example, non-metallic, yet dense composites may be used alone (or in combination with metallic materials) as shielding materials. Such non-metallic shielding materials may advantageously reduce the likelihood of 1) MRI artifacts that may be caused by metallic shielding materials, 2) deflection of insulating sheets, and / or 3) MRI induced heating, such as that caused by current loop induction and / or radio frequency induction heating of tissue. Depending on the particular non-metallic material, the thickness of the material may be greater than that required for metallic shielding materials, given the overall high shielding capacity of metallic materials. Non-metallic high density shielding materials may beneficially shield non-target tissue from radiation, especially in applications where MRI or other magnetic field exposure may be expected. Examples of non-metallic shielding materials include polyetheretherketone (PEEK), nanoparticles, polymeric nanoparticles, encapsulated nanoparticles, calcium carbonate, calcium phosphate, calcium sulfate, barium sulfate, zirconium dioxide, polymers and polymer hybrids of these and other materials. Shielding materials may be combined to form composite shielding materials. For example, a metal cylinder may be filled with (non-metallic) liquid calcium carbonate to form a shielding material that better addresses one or more of the patient's clinical needs than separate metal cylinders and liquid calcium carbonate, or solid metal rods.

[0087] Although specific metallic or non-metallic materials (e.g., specific forms of specific materials) are referred to in the examples, references to shielding materials herein can be realized with any other shielding materials (e.g., different forms and / or different materials) and / or combinations of shielding materials. For example, a gold rod shielding material may be replaced with a PEEK mesh shielding material that provides similar radiation absorption and / or reflection properties. The dimensions (e.g., width, height, radius, thickness, etc.) of various shielding materials that provide the same radiation absorption and / or reflection properties may vary from material to material.

[0088] Shielding layer: one or more shielding materials configured to be placed on or near a radioactive source (e.g., a seed) to reduce penetration of radiation outside of the treatment area. The shielding layer may comprise one or more separate layers of material, such as a gold foil sheet or a polymer sheet. In other embodiments, the shielding layer may include particles of high-Z or non-metallic material that may be embedded in a shielding layer substrate (comprising the shielding layer material), such as an encapsulant. In some embodiments, the shielding layer may be perforated or may include a grid or mesh pattern, for example interwoven with one or more high-Z materials. A perforated or mesh shielding layer may improve the effectiveness of an insulating sheet, for example, by configuring a shielding layer with desired radioactive shielding properties. A perforated or mesh shielding layer may also improve ease of handling (e.g., flexibility to allow placement in the treatment area in a desired configuration) and / or imaging properties (e.g., reduced artifacts from the shielding material).

[0089] Encapsulator: a device configured to be placed on or near a radioactive source (e.g., a seed) or attached thereto. The encapsulant may include one or more shielding layers configured to shield (e.g., block, absorb, and / or absorb) a portion of the radiation emitted by the radioactive seed, e.g., 5% to 95% of the radiation. The encapsulant may be generally cylindrical in shape, with at least a portion of the cylindrical shape open so that the central axis of the cylinder is visible from the outside of the encapsulant. For example, the encapsulant may be cylindrical with a longitudinal slit missing along the length of the cylinder. For example, the encapsulant may be a semicircular cylinder with 180 degrees of its circumference comprising a shielding layer and the opposite 180 degrees open. In this manner, the encapsulant may define a cavity (e.g., the inner cavity of the cylinder) configured to receive the radioactive seed. In some embodiments, the inner cavity of the encapsulant, or a portion thereof, may be generally cylindrical, or any other shape needed or desired to receive the seed and match the shape of the seed. For example, the inner cavity of the encapsulant may be shaped to receive a cylindrical seed, or a spherical seed, or a rectangular seed.

[0090] In some embodiments, the encapsulant may be configured to be placed or attached to the carrier without being directly bonded to the radioactive seeds. For example, a "carrier encapsulant" may be placed and / or repositioned on a surface of the carrier during a medical procedure, e.g., by a medical professional, to provide shielding from radiation from one or more radioactive seeds embedded in the carrier. In various implementations, the carrier encapsulant may cover a portion of the carrier surface, all of the carrier surface, or multiple carrier surfaces. The carrier encapsulant may be secured to the carrier by adhesion, e.g., by adhesive properties of the encapsulant and / or carrier. The carrier encapsulant may be secured to the carrier by one or more fasteners on the encapsulant configured to pierce the carrier and anchor the encapsulant to the carrier. The carrier encapsulant may be shaped to fit the shape and / or size of the carrier. For example, a carrier encapsulant configured to be placed on a top surface of a tile carrier may be generally planar and sized to match the size of the top surface. In another example, a carrier encapsulant configured to be placed on a spherical surface of a carrier (e.g., an upper surface of a spherical carrier) may be generally spherical and have an inner cavity configured to receive the spherical surface of the carrier such that the encapsulant fits on or around the spherical surface.

[0091] A radioactive seed coupled to an encapsulant may generally be referred to as an "encapsulated radioactive seed." The radioactive seed may be attached to the encapsulant by a friction-fit and / or snap-fit ​​assembly. For example, the encapsulant may be flexible enough to expand the diameter of the inner cavity to allow the radioactive seed to be inserted therein. The seed within the cavity may then be held in place by a snap-fit ​​or friction-fit between the encapsulant and the radioactive seed. For example, the snap-fit ​​may be achieved by one or more protrusions or other mechanical features on the edge of the encapsulant that extends into the inner cavity. Generally, the terms "radioactive seed" or "seed" as used herein may refer to any of the radioactive seeds and / or encapsulated radioactive seeds described above.

[0092] The encapsulated radioactive seeds may be mounted or embedded within a carrier and placed adjacent to the treatment surface of the patient to deliver radiotherapy, or the encapsulated radioactive seeds may be placed directly on the treatment surface without being mounted on a carrier.

[0093] The encapsulant may comprise one or more materials, such as plastics, polymers, or other biocompatible materials, embedded with one or more shielding materials. Alternatively, the encapsulant may be entirely composed of the shielding material. The encapsulant may comprise a single continuous material or may comprise discrete layers of material. In some embodiments, the encapsulant may not include a shielding material and may be used to hold the seed, for example, to facilitate loading of the seed into the carrier. A radioactive seed is positioned within a cavity of the encapsulant such that radiation emitted from the seed is shielded in the direction of the encapsulant shielding material, while radiation may exit the seed and / or encapsulant in a direction not including the shielding material (e.g., of the encapsulant cavity opening) and into the patient's tissue for adjuvant therapy.

[0094] The encapsulation may be customized for a particular patient and / or treatment plan, for example, the openings in the encapsulation may be adjusted to reduce or increase the area through which radiation is delivered from the encapsulated radioactive seeds.

[0095] Shielding specification (also called shielding plan): attributes of one or more encapsulated radioactive seeds, such as attributes of the shielding layer and any other layers (e.g., collagen or other spacing layers, adhesive layers, etc.) included in the encapsulation, such as the shape, size, cavity dimensions, shielding material, shielding layers, and / or any combination of these attributes (also called "features" herein) of the encapsulation. Shielding specifications may be in digital form (e.g., electronic data structures such as databases or tables), written form (handwritten by an oncologist or surgeon or printed from a digital form), and / or may be created and / or updated without (or before) the deployment of the encapsulated radioactive seeds. In this manner, shielding specifications may be created in real time based on clinical needs and / or other patient characteristics.

[0096] The shielding specifications may be determined to best meet one or more of a number of clinical needs (and / or other shielding objectives or requirements), for example to provide the following shielding: Shielding to create a directional treatment field. A radiation source, e.g., a carrier embedded with radioactive seeds, generally emits radiation in all directions, causing the entire area around the source to absorb the radiation (possibly in different amounts depending on the shape, size, placement, etc. of the source). Shielding specifications may include the use of encapsulated radioactive seeds, which reduce the range of radiation by blocking emitted radiation in certain directions; Shielding to reduce the risk of imaging distortion due to interference from shielding materials (or other components); · Shielding to reduce the risk of RF heating caused by energy from the MRI or other imaging device, and therefore the risk of further patient injury as a result of imaging, e.g. burns; Shielding to provide a preferred (or, in some embodiments, required) shape, size, etc. of the encapsulant, for example to allow placement of the encapsulated radioactive seeds in an irregularly shaped treatment area; and / or · Shielding to reduce the risk of the shielding material being deflected (e.g., moving) within the encapsulation by energy from imaging devices such as MRI.

[0097] Dosimetry: The process of measurement and quantitative description of the absorbed dose (e.g., rad) of radiation in a tissue or organ.

[0098] Dosimetry plan: a prescribed dosimetry description, e.g., for a particular patient associated with a particular clinical condition and / or for use in a particular surgical cavity, etc. For example, a dosimetry plan may indicate the location, quantity, radioactive intensity, etc. for placing radioactive carriers on the treatment surface of the patient, taking into account, e.g., the characteristics of a tumor removed (or planned to be removed) from the patient. In some embodiments, a dosimetry plan may include shielding specifications (or "shielding plans"), such as the characteristics of one or more encapsulants to be used in conjunction with radioactive seeds (e.g., encapsulated radioactive seeds) according to the dosimetry plan. In other embodiments, a dosimetry plan for a patient may not include shielding specifications, e.g., leave the determination of shielding specifications to another expert, e.g., the surgeon implementing the dosimetry plan. In this way, the shielding specifications may be determined based on clinical needs, either in real time when some of the prescribed radioactive carriers are positioned on the treatment surface, or at a later time. Determining shielding specifications based on clinical need can better accommodate the patient's actual clinical condition, which may be unknown and / or change after dosimetry planning, e.g., after tumor removal. In some embodiments, clinical need may be taken into consideration to increase shielding around sensitive tissue areas (e.g., optic nerves, vital organs, etc.) or scar tissue areas. Any discussion herein of determining shielding specifications as a function of a dosimetry plan, which is a type of "treatment plan" specific to radiation therapy planning, also refers to determining these same shielding specifications as a function of clinical need, whereby shielding specifications may be determined based on dosimetry planning and / or clinical need.

[0099] Therapeutic index: the relationship of the amount of therapeutic effect provided by a therapeutic agent, such as one or more radioactive seeds in a carrier, to the amount that causes toxicity. Therapeutic index may indicate the relative amount of healthy tissue (e.g., non-target tissue) that receives radiation (e.g., above a certain dose level) compared to the amount of the target area (e.g., tumor or tumor bed) that receives radiation. Therapeutic index may be the ratio of radiation delivered to the treatment area (e.g., tumor or tumor bed) to the radiation delivered to the area around the treatment area. Thus, a higher therapeutic index generally indicates that the radiation is better localized to the treatment area, sparing as many surrounding areas as possible. Thus, an improved therapeutic index may increase local control of the tumor and / or reduce side effects of the treatment. Exemplary Carrier Embodiments

[0100] 1A and 1B are cross-sectional views of portions of patient tissues 102 and 112 having tumor beds 104 and 114 therein, respectively. These tumor beds 104 and 114 may have been created by a surgical process, such as a tumor debulking process, in which tumor cells have been removed. For example, tissues 102 or 112 may represent human (or other mammal) cranial tissue, and tumor beds 104 and 114 have been surgically created to remove one or more tumors from the patient's brain (and / or surrounding areas). Thus, tissues 102 and 112 may represent different types of material, such as bone, adipose tissue, brain tissue, etc. Any reference to "tissue" herein may refer to any type of mammalian material, including bone, adipose tissue, brain tissue, etc.

[0101] In the example of FIG. 1A, four tile carriers 106 are shown as already positioned within the tumor bed 104. Positioning of the tiles 106 into the tumor bed 104 may occur in an operating room, such as immediately after the surgical procedure, or may occur elsewhere at some point after the surgical procedure, such as in another procedure performed hours, days, or weeks later. In the embodiment of FIG. 1A, the tiles 106 are flexible to conform to the treatment surface, which in this example is the non-planar outer surface of the tumor bed 104. In one embodiment, the tiles 106 may include collagen, which provides such flexibility in conforming the tiles 106 to the non-planar surface. In the example of FIG. 1B, the tiles 116 that are positioned in the tumor bed 114 of the tissue 112 are comprised of a non-pliable substrate, e.g., a polymer, that maintains its substantially planar shape even when positioned within the tumor bed 114. For ease of discussion, the tile carriers discussed herein are shown as flexible, such as the tiles 106 of FIG. 1A. However, any other type of tile carrier, as well as carriers of other configurations, such as gore, star, or dot carriers, may alternatively be used. Thus, any discussion herein of a tile carrier or any other particular carrier should be construed to also include embodiments that use other types of carriers, embodiments without a carrier at all (e.g., radioactive seeds that can be placed in the tumor bed without first being placed in a carrier), and / or any other radiation delivery device.

[0102] In the example of Figures 1A and 1B, the tiles 106 and 116 each include radioactive seeds embedded therein. As discussed in the related patents and patent applications mentioned above, the radioactive seeds can have a variety of shapes, sizes, and characteristics. In the examples discussed herein, the radioactive seeds are shown as generally cylindrical, such as the cylinders included in each of the tiles 106 and 116 in Figures 1A and 1B. However, in other implementations, other shapes and sizes of seeds may be used. In the examples discussed herein, the radioactive seeds are substantially rigid, such that they maintain their shape within their respective carriers. Thus, as shown in Figure 1A, even when the carrier 106 near the bottom of the tumor bed 104 is deformed to better engage the treatment surface, the seeds therein retain their linear cylindrical shape. In other embodiments, the seeds may be more pliable, such that they have some flexibility in taking on the shape of a particular treatment surface. In the example of FIG. 1C, no tumor cavity is present, so carrier 126 is placed over a substantially planar treatment area of ​​tissue 122, such as the patient's skin overlying the skull, or other tissue.

[0103] In the examples of Figures 1A, 1B, and 1C, radiation is delivered to the corresponding treatment area by the radioactive seeds in the carriers 106, 116, and 126, respectively. However, radiation from these seeds may extend to other areas of tissue outside the desired treatment area. For example, radiation emitted from the top surface of the carrier may extend to surrounding tissue outside the treatment area, other parts of tissue near and / or in contact with the treatment surface (e.g., the patient's hand resting on the tumor bed 104), or even to tissue of another person or animal, such as the tissue of a spouse who is near the treatment surface and therefore receives radiation from the radioactive seeds. Thus, depending on the placement of the carrier, the size and shape of the treatment surface, the strength of the radioactive seeds, and / or numerous other factors, the therapeutic index for using such carriers may be unnecessarily low. Discussed herein are various shielding devices, systems, and methods generally designed to improve the therapeutic index for delivering radiation using brachytherapy.

[0104] 2A shows a perspective view of a tile carrier 200 that serves as a loadable spacer for radioactive seeds 299. Additionally, the tile carrier 200 may include an antipodal surface 210 opposite the treatment surface 220.

[0105] 2B shows a cross-sectional view of an exemplary tile carrier 200. Cross-section 251 is a top view of the exemplary tile carrier 200. Cross-section 252 is a front view of the exemplary tile carrier 200 with embedded seeds 299. Cross-section 253 is a side view of the exemplary tile carrier 200 with embedded seeds 299. Exemplary Encapsulant Embodiments

[0106] Disclosed herein are several embodiments of encapsulants, which are generally any material disposed over, around, and / or included with radioactive seeds to provide directional radioactive shielding. As noted above, the encapsulant may include a single shielding layer that may itself include one or more shielding materials, or may include multiple shielding layers in various positions relative to one another. The encapsulant may improve the therapeutic index associated with a dosimetry plan. Shielding materials used in the encapsulant may include various forms of high-z materials or alloys thereof formed into a shielding layer, such as foils, meshes, oriented strips, grids, embedded, sprayed, bio-bonded, or overlayed, in or on a substrate, such as one or more layers of plastic or polymer. Specific shapes, materials, compositions, properties, and the like are disclosed herein with reference to various exemplary encapsulants, although variations of these examples are anticipated.

[0107] FIG. 3A is a perspective view of an exemplary embodiment of an encapsulant 303A. In the example of FIG. 3A, the encapsulant 303 is generally cylindrical in shape and includes a central cavity 302 sized to fit around (and / or engage) a cylindrical radioactive seed. For ease of description herein, the encapsulant is described as having a generally cylindrical shape, such as in FIG. 3A. However, any other shape of encapsulant having the same or similar characteristics is also contemplated. As such, any discussion of features or characteristics of an encapsulant of a particular shape (e.g., cylindrical with a central cavity) is also applicable to any other shape of encapsulant not specifically discussed herein. For example, other embodiments of the encapsulant may include a cavity that is generally cylindrical, spherical, cuboid, or rectangular in shape, e.g., to match the shape of the seed. Other embodiments of the encapsulant, sometimes referred to herein as a "carrier encapsulant," may be shaped to fit around or on a carrier or a portion thereof. For example, the carrier encapsulant may be generally planar so as to be placed on a surface of the tile carrier, or the encapsulant may be generally spherical so as to fit into or around a spherical carrier or a portion thereof, or may include a cavity that is generally rectangular in shape, for example, to match the shape of the tile carrier. For ease of explanation, an exemplary seed that is generally cylindrical in shape is discussed herein. However, seeds of any other shape may be used in conjunction with the encapsulant as well.

[0108] In some embodiments, the encapsulant 303A may include a single material, such as, for example, a single shielding material, which may be a homogenous or continuous material, or a single non-shielding material. For example, the encapsulant 303A may include a single plastic or polymer, or other biocompatible material, or may include a single high-Z material. In some embodiments, the encapsulant 303A may include more than one material, such as separate layers, portions, or sections of different materials. The encapsulant 303A may be manufactured by extrusion, injection molding, 3D printing, or the like.

[0109] 3B illustrates another example of an encapsulant 303B that includes a shielding layer 305 embedded within a non-shielding material 306 that forms the remainder of the encapsulant 303B. As discussed further herein, the shielding material may be embedded within and / or attached to the non-shielding material to form encapsulants of various configurations.

[0110] The shielding layer 305 may include one or more high-Z materials. For example, the shielding layer 305 may include gold (Au) or tantalum (Ta). In some embodiments, the shielding layer 305 may include an electroplated layer of a high-Z material, such as gold. In some embodiments, the encapsulant may include more than one shielding layer, for example two or three separate shielding layers, each positioned within the encapsulant at various distances away from the seed and separated from each other by a portion, section, or layer of a non-high-Z material of the encapsulant, such as a plastic or polymer.

[0111] In some embodiments, the shielding layer may have a variable thickness along the length of the seed and / or around the periphery of the seed. A variable thickness shielding layer may allow radiation to be delivered at different doses to different areas of the tumor bed, for example, depending on a prescribed treatment plan. In some embodiments, the shielding layer may have a thickness between about 0.01 mm and 0.06 mm, between about 0.02 mm and 0.03 mm, between about 0.025 mm and 0.035 mm, between about 0.03 mm and 0.04 mm, or any other thickness. In some embodiments, the shielding layer 305 may have a thickness of about 0.026 mm or about 0.036 mm.

[0112] The thickness and / or material of the shielding layer 305 may depend on the desired dosimetry plan. For example, it may be desired that the shielding layer 305 has a certain half value layer (HVL). The HVL is the thickness of the material at which the intensity of the radiation entering it is reduced by a factor of two. In some embodiments, the shielding layer 305 may have an HVL of 1, 1.5, 2, 2.5, 3, or other HVL. In some embodiments, the shielding layer 305 may have an HVL of 2, such that the intensity / magnitude of the radiation entering the shielding layer 305 from the radioactive seeds is reduced by a factor of four before exiting the shielding layer 305. The HVL may vary depending on the material. Thus, for some materials, a thicker shielding layer 305 may be required to reduce the radiation intensity / magnitude by the same amount as other materials. In some embodiments, the shielding may be prescribed as a percentage of dose reduction. For example, the shielding layer may provide a dose reduction of between about 30% and 90%.

[0113] 3C shows an encapsulant 303B with a radioactive seed 301 positioned in the encapsulant cavity. This combination of encapsulant and radioactive seed is referred to herein as an encapsulated seed, such as encapsulated seed 304. As discussed further herein, the radioactive seed may be coupled to the encapsulant by various means, such as a friction fit, a snap fit, and / or an adhesive.

[0114] In the embodiment of FIG. 3C, the seed 301 is rod-shaped or cylindrical. Depending on the embodiment, the seed 301 may have a length between about 4 mm and 5 mm, or any other length as needed or desired. In some embodiments, the seed 301 may have a length of 4.5 mm. The seed may have a diameter between about 0.65 mm and 0.75 mm, between about 0.7 mm and 0.8 mm, or between about 0.75 mm and 0.85 mm. In some embodiments, the seed 301 has a diameter of about 0.7 mm, or about 0.8 mm, or about 0.9 mm.

[0115] In some embodiments, the encapsulant 303 (e.g., encapsulant 303A, 303B, or any other encapsulant discussed herein) may be attached to the seed 301 by adhesion. For example, the encapsulant 303 may include an adhesive surface and / or material on an inner cavity surface that adheres the seed 301 to the cavity walls of the encapsulant 303. In some embodiments, the encapsulant 303 may be secured to the seed 301 by mechanical force. For example, the encapsulant 303 may surround a majority of the peripheral surface of the seed 301, e.g., such that the seed 301 is press-fit or snap-fit ​​within the encapsulant 301.

[0116] In some embodiments, the encapsulant 303 may be removably secured to the seed 301 such that the seed 301 may be inserted into or removed from the encapsulant 303. The encapsulant 303 may be quickly and easily applied to the seed 301, for example, by gluing or snap-fitting. For example, a medical professional may place the encapsulant 303 on the seed 301 during a medical procedure prior to placing the encapsulated seed 304 in the patient's tumor bed. The medical professional may place the encapsulant 303 on the seed 301 according to a desired dosimetry plan or radiation dose desired to be delivered to the patient.

[0117] 3C, the encapsulant 303B has a uniform thickness along the length of the seed 301. For example, the encapsulant 303B may have a thickness between about 0.1 mm and 0.2 mm, between about 0.15 mm and 0.25 mm, between about 0.2 mm and 0.3 mm, or any other thickness. In some embodiments, the encapsulant 303B may have a thickness of 0.2 mm. In some embodiments, the encapsulant may have a variable thickness along the length of the seed and / or around the circumference of the seed.

[0118] In some embodiments, the shielding layer 305 may be closer to the seed 301 or farther from the seed 301 than shown in the encapsulant 303B. For example, in some embodiments, the shielding layer 305 may be positioned closer to the cavity wall of the encapsulant 303B such that the shielding layer 305 is closer to the seed 301 or even in physical contact with the seed 301. As another example, in some embodiments, the shielding layer 305 may be positioned in an outer region of the encapsulant 303B such that the shielding layer 305 is closer to or even exposed on the outer surface of the encapsulant 303B. The shielding layer 305 may be positioned at any distance from the cavity wall of the encapsulant 303B, which may be uniform or variable along the length of the encapsulant 303B and / or around the circumference of the encapsulant 303B.

[0119] FIG. 3D is a perspective view of another exemplary encapsulated seed 304D including an encapsulant 303D and a seed 301 positioned within a central cylindrical cavity of the encapsulant 303D. In this example, the encapsulant 303D includes only a non-high-Z material, such as a plastic or polymer. The encapsulant 303D may include a uniform, continuous non-high-Z material, or may include separate layers, portions, or sections of various non-high-Z materials. In such embodiments where the encapsulant 303D does not include a shielding layer, the encapsulant 303D may be used to facilitate placement of the seed 301 within a carrier, as discussed elsewhere herein, for example with reference to FIGS. 10A-10B and 11. Any of the encapsulant embodiments discussed herein may be realized with or without a shielding layer.

[0120] FIG. 3E is a perspective view of another exemplary encapsulated seed 304E including an encapsulant 303E and a seed 301 positioned within a central cylindrical cavity of the encapsulant 303E. In this embodiment, the encapsulant 303E includes only a shielding layer 315E without a corresponding non-shielding layer. The shielding layer 315E may include a uniform, continuous high-Z material or may include separate layers, portions, or sections of various high-Z materials, such as foils having thicknesses ranging from 0.01 mm to 0.06 mm. In the embodiment of FIG. 3E, the encapsulant 303E (corresponding to the shielding layer 315E in the particular embodiment of FIG. 3E) may include adhesive properties and / or substances to facilitate adhesion of the seed 301 to the cavity walls of the encapsulant 303E. This may facilitate quick and easy application of the encapsulant 303E to the seed 301 and of the shielding layer 315E. For example, a medical professional may place an encapsulant 303E on a seed 301 during a medical procedure prior to placing the encapsulated seed 304E in a patient's tumor bed. A medical professional may place the encapsulant 303E on a seed 301 depending on a desired dosimetry plan or radiation dose to be delivered to a patient. Any of the embodiments of the shielding layer discussed herein may be implemented as the encapsulant itself (as with the encapsulant 303E) and / or in conjunction with one or more non-shielding and / or additional shielding layers.

[0121] FIG. 3F is a perspective view of another exemplary encapsulant 303F. In this example, the encapsulant 303F is cylindrical in shape and more than half (e.g., more than 180 degrees) of the circumference of the cylinder remains intact. Thus, the opening to the cavity 302F is narrower than the diameter of the cavity 302F. Thus, a seed having an outer diameter approximately equal to (or slightly smaller than) the diameter of the cavity 302F may be snapped into the cavity 302F by pressing the seed against the entrance of the cavity 302F of the encapsulant 303F, bending the encapsulant 303F slightly, thereby allowing the seed to enter the cavity 302F. Once in the cavity 302F, the seed 303F is held in place. FIG. 3G shows the same encapsulant 303F with a radioactive seed 303 placed therein and held in place due to the narrow entrance to the cavity 302F. Any other embodiments of the encapsulant discussed herein may include similar snap-fit ​​configurations and / or features, such as where moving the seed toward the cavity of the encapsulant causes a portion of the encapsulant to bend outward until the seed snaps through an opening into the cavity of the encapsulant.

[0122] 4A is an end view 410 and a cross-sectional view 411 of another exemplary encapsulant 413 having a shielding layer 415 on or around a seed 301. As shown in cross-sectional view 411, the length of the shielding layer 415 can be coextensive with the length of the encapsulant 413 and the length of the seed 301. As shown in cross-sectional view 411, the edges of the shielding layer 415, encapsulant 413, and seed 301 can all be coplanar at one or both ends.

[0123] 4B is an end view 420 and a cross-sectional view 421 of another exemplary encapsulant 423 having a shielding layer 425 adjacent to or around a seed 301. As shown in cross-sectional view 421, in some embodiments, the length of the shielding layer 425 may not be coextensive with the length of the encapsulant 423 and / or the length of the seed 301. The ends of the shielding layer 425 may not be coplanar with the encapsulant 423 and / or the seed 301 on one or both ends.

[0124] 4C is an end view 430 and a cross-sectional view 431 of another exemplary encapsulant 433 having a shielding layer 435 on or around a seed 401. As shown in cross-sectional view 431, in some embodiments, the length of encapsulant 433 may not be coextensive with and / or equal to the length of seed 401. For example, as shown, seed 401 may be longer than encapsulant 433 such that one or both ends of seed 401 extend beyond the ends of encapsulant 433. In some embodiments, seed 401 may be shorter than encapsulant such that one or both ends of seed do not extend beyond the ends of encapsulant. Advantageously, by encapsulating only a portion of seed 401 with encapsulant 433, the desired dose of radiation delivered to the patient may be improved. For example, by encapsulating only a portion of seed 401, radiation emanating from seed 401 in the encapsulated portion may be directionally blocked, while radiation in other, unencapsulated portions of seed 401 may be allowed to emit in all directions.

[0125] 4D is an end view 440 and a cross-sectional view 441 of another exemplary encapsulant 443 having a shielding layer 445 on or around the seed 402. As shown in cross-sectional view 441, in some embodiments, the encapsulant 443 includes a cap portion 406 (including cap portions 406A and 406B) at each end. The cap portion 406 may include additional shielding layers 446 (including shielding layers 446A and 446B positioned at both ends of the encapsulant 443) that may reduce radiation from the seed 402 from extending away from the seed 402 in one or both directions along a direction substantially parallel to the longitudinal axis of the seed 402. In some embodiments, the cap portion 446 may facilitate retention of the seed 402 within the encapsulant 443. For example, the cap portion 406 may be configured to retain the seed 402 within the cavity of the encapsulant 443 via a snap or friction fit between the cap portion 406 .

[0126] 4E is an end view 450 and a cross-sectional view 451 of another exemplary encapsulant 453 having a shielding layer 455 on or around a seed 301. As shown in cross-sectional view 451, in this exemplary embodiment, the shielding layer 455 has a variable thickness along the length of the seed 301. For example, the shielding layer 455 is thicker at one end than the other, thereby blocking more radiation from the seed 301 at one end than the other, providing variable radiation as prescribed, for example, in a radiation treatment plan. Any other variations in the thickness of the shielding layer 455 along the length of the seed are contemplated as needed or desired, for example, depending on a dosimetry plan.

[0127] 4F is an end view 460 and a cross-sectional view 461 of another exemplary encapsulant 463 having a shielding layer 465 on or around a seed 301. As shown in cross-sectional view 461, in this exemplary embodiment, the shielding layer 465 has a variable thickness around the perimeter of the portion of the seed 301 to be shielded. For example, the shielding layer 465 is thicker on one side than the other side, thereby shielding more radiation on one side of the seed 301 than the other side, providing variable radiation as prescribed, for example, in a radiation treatment plan. Any variation in the thickness of the shielding layer 465 around the perimeter of the seed is contemplated as needed or desired depending, for example, on a dosimetry plan.

[0128] 5A-5C are end views of additional examples of encapsulated seeds 504 (including encapsulated seeds 504A, 504B, 504C) having encapsulants extending around different portions of the circumference of seed 301. In the example of FIG. 5A, encapsulant 503 including shielding layer 505 extends around less than half (e.g., less than 180 degrees) of the circumference of seed 301. In the particular example of FIG. 5A, encapsulant 503 and shielding layer 505 extend around approximately 80 degrees of the circumference of seed 301.

[0129] In the example of Figure 5B, the encapsulant 513, including the shielding layer 515, extends around more than half the circumference of the seed 301. In the particular example of Figure 5B, the encapsulant 513 and the shielding layer 515 extend around approximately 270 degrees of the circumference of the seed 301.

[0130] As shown in Figures 5A-5B, by providing more or less encapsulant around the seed, the amount and / or direction of radiation emitted by the seed and delivered to the patient may be altered, e.g., to match a radiation dose prescribed in a radiation treatment plan. Additionally, by providing more or less encapsulant around the seed, it may be easier to secure the encapsulant to the seed. For example, an encapsulant that extends more than 180 degrees around the seed may be secured to the seed by a snap fit or friction fit (see, e.g., Figures 3F-3G).

[0131] In the example of FIG. 5C, the encapsulant 523 includes two shielding layers 525 (including shielding layers 525A and 525B) positioned around the seed 301. As shown, the exemplary encapsulant 523 extends around the entire perimeter of the seed 301, which may advantageously hold the seed 301 in place more securely within the encapsulant 523. Additionally, as shown in FIG. 5C, in some embodiments, the encapsulant 523 may include more than one shielding layer 525, such that the shielding layers 525 are physically separated from one another within the encapsulant 523 and block different directions and / or amounts of radiation exiting the seed. Advantageously, the encapsulant 523 may thus be configured to deliver a particular dose of radiation in a particular direction relative to the patient. Exemplary Carrier Implementations

[0132] 6A is a cross-sectional end view of carrier 607 with seeds 601 (including seeds 601A and 601B) embedded therein. As shown, encapsulant 603 (including encapsulants 603A and 603B) each include shielding layer 605 (including shielding layers 605A and 605B) configured to shield radiation from approximately 180 degrees around seed 601 without shielding radiation directed toward carrier 607. As shown, seed 601 is partially embedded within carrier 607.

[0133] In some embodiments, the seed and / or encapsulant may be adhered to the carrier using the carrier's inherent adhesive properties and / or a separate adhesive. As noted above, certain carrier materials may have inherent tackiness that adheres the carrier to the seed and / or encapsulant. For example, a collagen carrier may be adhered to the seed and / or encapsulant without the need for additional adhesive materials or attachment mechanisms.

[0134] In the embodiment of FIG. 6A, the encapsulant 603B includes a fastener 609. The fastener 609 may be configured to protrude into the carrier 607 to a certain depth, thereby securing the encapsulant 603B (and thus the seed 601B) to the carrier 607. The fastener 609 may be pointed and / or cylindrical, such as a nail or rod, or may be curved, such as a hook. The fastener 609 may be elongated and extend along the length of the encapsulant 603B. The fastener 609 may include a barb to prevent backing out of the encapsulant 603B from the carrier 607 without compromising ease of insertion into the carrier 607.

[0135] In some embodiments, in addition to the biocompatibility of the carrier, other components of the encapsulated seed (e.g., fasteners 609, 619; protrusions 711; connectors 808, 818, 908, 1008, 1028, 1108; protrusions 1011, 1012; anchors 1026; and / or any other components discussed herein) may comprise biocompatible materials. Furthermore, in some embodiments, these components may be bioabsorbable, e.g., such that the encapsulant is naturally absorbed into tissue at the same or similar rate as the carrier to which it is attached or embedded. For example, such bioabsorbable components (e.g., fasteners with sharp edges) do not remain in tissue after the carrier is naturally absorbed into tissue.

[0136] In embodiments where the seeds are partially embedded within the carrier, the encapsulant may be applied to the seeds and / or removed from the seeds after the seeds are already disposed within the carrier. Such implementations may facilitate the production of directionally shielded seed carriers with the seeds already inserted within the carrier but without directional radiation shielding such as an encapsulant.

[0137] 6B is a cross-sectional end view of carrier 617 with seeds 601A and 601C embedded therein. As shown, encapsulants 603A and 603C with shielding layers 605A and 605C are positioned around seeds 601A and 601C to block radiation emanating from seeds 601 in a particular direction. In this example, seeds 601 and encapsulant 603 are entirely embedded within carrier 617. In this embodiment, an additional shielding layer 650 is disposed on the surface of carrier 617. Shielding layer 650 may cover the entire surface of carrier 617 or only a portion of the surface. In some embodiments, one or more shielding layers 650 may be disposed on more than one surface of carrier 617. Shielding layer 650 may be implemented in addition to or instead of encapsulant 603 and / or shielding layer 605 of encapsulant 603. The shielding layer 650 may provide additional radioactive shielding to achieve a desired radiation dose (e.g., amount and / or direction of radiation) delivered to a patient. The shielding layer 650 may be realized in the form of a sticker, for example, having adhesive properties configured to allow for easy application and attachment of the shielding layer 650 to a carrier. In some embodiments, the shielding layer may be configured to be customized, such as by cutting or tearing the shielding layer to create a custom shaped and / or sized shielding layer that can be placed on or around one or more carriers.

[0138] The shielding layer 650 may be secured to the carrier 617 by adhesion. In some embodiments, the shielding layer 650 may be configured to have adhesive properties or an adhesive substance to facilitate application and placement on the carrier 617. In some embodiments, the shielding layer 650 may be secured to the carrier 617 by adhesive properties of the carrier 617. For example, the carrier 617 may be made of a material that has inherent tackiness that may bond the shielding layer 650 to the carrier 617. (e.g., collagen). Adhering the shielding layer 650 to the carrier 617 may facilitate quick and easy application of the shielding layer 650 to the carrier 617. For example, a medical professional may place the shielding layer 650 on the carrier 617 during a medical procedure prior to (or after) placing the carrier 617 in the patient's tumor bed. The medical professional may place the shielding layer 650 on the carrier 617 depending on the desired radiation dose or dosimetry plan to be delivered to the patient. For example, the medical professional may place the shielding layer 650 on a particular surface of the carrier 617 as desired.

[0139] 6C is a cross-sectional end view of carrier 627 with seeds 601 (including seeds 601D and 601E) and encapsulant 603 (including encapsulant 603D and 603E) embedded therein. As shown, the encapsulated seeds (e.g., a combination of seeds 601 and corresponding encapsulant 603) may be positioned at various locations throughout carrier 627. Additionally, encapsulated seeds 603 may be oriented differently from one another to adjust the shielding direction of each seed 601 in a non-uniform direction. For example, as shown, encapsulant 603D is positioned to shield radiation traveling in an upward direction (relative to the page) and encapsulant 603E is positioned to shield radiation traveling in a rightward direction (relative to the page). Encapsulated seeds 601 may be positioned in this manner to achieve a dosimetry plan.

[0140] 6D is a perspective view of carrier 627. In this example, embedded seeds 601 and encapsulant 603 are not visible from the outside of carrier 627. A medical professional may wish to know the placement of seeds 601 or the orientation of encapsulant 603 (and any corresponding shielding) within the carrier to know the direction in which radiation is shielded and / or emitted. In this exemplary embodiment, carrier 627 includes indicators 621D and 621E that indicate the direction of shielding of the encapsulated seeds embedded in carrier 627. Such indicators allow a medical professional during a medical procedure to place the carrier (with encapsulated seeds) in a desired location and orientation. For example, indicator 621D indicates that encapsulated seeds 601D are positioned within carrier 627 below indicator 621D in alignment with indicator 621D, and that radiation is shielded from emitting from carrier 627 in the direction of the surface of carrier 627 where indicator 621D is positioned (e.g., generally upwards relative to the page). As another example, indicator 621E indicates that encapsulated seed 601E is positioned within carrier 627 adjacent to indicator 621E in alignment with indicator 621E, and that radiation is shielded from emitting from carrier 627 in the direction of the surface of carrier 627 on which indicator 621E is positioned (e.g., generally to the right relative to the page).

[0141] In some embodiments, the indicator may be pad printed or laser printed on the surface of the carrier. In some embodiments, the indicator may be a dotted line, as shown in FIG. 6D, to match the shape of the encapsulated seed, e.g., cylindrical, or any other shape or marking to indicate the placement of the encapsulated seed within the carrier and / or to indicate the direction of shielding and / or emission of radiation. In some embodiments, the indicator may include additional information, such as the depth of the encapsulated seed, the amount of shielding, the amount of radiation emitted by the seed, etc.

[0142] FIG. 6E is a cross-sectional end view of a carrier 637 with a seed 601F embedded therein. As shown, an encapsulant 603F (which may be referred to as a carrier encapsulant) having a shielding layer 605F is disposed on the carrier 637 to shield radiation emitted from the seed 601F in a generally upward direction (relative to the page). In the embodiment of FIG. 6E, the encapsulant 603F includes a fastener 619. The fastener 619 may be configured to protrude into the carrier 637 to a depth to secure the encapsulant 603F to the carrier 637. The fastener 619 may be pointed and / or cylindrical, such as a nail or rod, or may be curved, such as a hook. The fastener 619 may be elongated and extend along the length of the encapsulant 603F. The fasteners 619 may include barbs to prevent backing out of the encapsulant 603F from the carrier 637 without compromising easy insertion into the carrier 637. In some embodiments, the encapsulant 603F may not include fasteners and may be secured to the carrier 637 by adhesion. For example, the adhesive properties of the encapsulant 603F and / or the carrier 637, which may be made from collagen with inherent tackiness, may secure the encapsulant 603F to the carrier 637.

[0143] In some embodiments, the encapsulant 603F may be removably secured to the carrier 637 such that the encapsulant 603F may be placed on the carrier 637 and then removed from the carrier 637 and repositioned. The encapsulant 603F may be quickly and easily applied to the carrier 637, for example, by adhesive or fasteners. For example, a medical professional may place the encapsulant 603F on the carrier 637 during a medical procedure prior to placing the carrier 637 in the tumor bed of a patient. The medical professional may place the encapsulant 603F on the carrier 637 depending on a desired dosimetry plan or radiation dose to be delivered to the patient. In some implementations, a carrier encapsulant, such as the encapsulant 603F, may be used in conjunction with a seed encapsulant. For example, to provide more directional shielding of radiation, the seeds 601F may each be coupled to an encapsulant that provides directional shielding, for example, upwards towards the encapsulant 603F.

[0144] 6F is a perspective view of an encapsulant 603G (sometimes referred to as a carrier encapsulant) having a shielding layer 605G disposed on or around a carrier 647 to block radiation in a particular direction from the seeds within the carrier 647. In an exemplary embodiment, the encapsulant 603G is generally spherical and may be sized to fit on or around the spherical carrier 647.

[0145] FIG. 6G is an end cross-sectional view of an encapsulant 603G. As shown, the encapsulant 603G includes fasteners 629 that may be configured to secure the encapsulant 603G to the carrier 647, for example, as described with reference to FIG. 6E. In some embodiments, the encapsulant 603G may not include fasteners and may be secured to the carrier 647 by adhesion. In some embodiments, the encapsulant 603G may be secured to the carrier 647 by a snap fit or friction fit. For example, the encapsulant may have a diameter slightly smaller than the diameter of the carrier, such that when the carrier is placed within the encapsulant, the carrier may deform to a size smaller than its normal size, thus exerting an outward force on the inner cavity of the encapsulant, which may hold the carrier in place. As another example, the perimeter of the encapsulant may include more than half (e.g., more than 180 degrees) of the encapsulant in its entirety. In this manner, the diameter of the opening into the inner cavity of the encapsulant may be smaller than the diameter of the inner cavity. Thus, a carrier having an outer diameter approximately equal to or slightly smaller than the diameter of the inner cavity of the encapsulant may be snapped into the cavity of the encapsulant by pressing the seed against the entrance to the encapsulant cavity, slightly bending the encapsulant and / or slightly deforming the carrier, thereby allowing the carrier to enter the encapsulant cavity. Once in the cavity, the carrier is held in place.

[0146] 7A-7C show exemplary encapsulants 703 (including encapsulants 703A, 703B, 703C) having a shielding layer 705 and protrusions 711 positioned at various locations on the exterior surface of the encapsulant 703. The protrusions 711 may be pointed and / or cylindrical, such as pegs, or rods, or pyramids. The protrusions 711 may be elongated and extend along the length of the encapsulant 703, for example, as shown with reference to FIG.

[0147] The protrusions 711 may increase the rotational inertia of the encapsulated seeds (e.g., encapsulant 703 and corresponding seeds 701) such that more force is required to rotate the encapsulated seeds relative to the carrier they are at least partially embedded in. For example, when the protrusions 711 are embedded in the carrier, they may prevent the encapsulated seeds from rotating within the carrier, preventing the orientation of the radiation shielding from being changed after the encapsulated seeds are attached to and / or embedded in the carrier.

[0148] In some embodiments, the protrusions 711 may indicate the direction of radiation shielding provided by the encapsulated seeds. For example, as shown and discussed with reference to FIG. 10B, one or more protrusions of the encapsulant embedded in the carrier may be visible from the side of the carrier to indicate the direction of radiation shielding, for example, to a manufacturer and / or a physician. For example, as shown in FIG. 7A or 7C, the downwardly facing protrusions 711 may be flush with the side of the carrier or may extend partially outwardly from the carrier, such that the downwardly facing protrusions 711 may be visible from the exterior of the carrier and indicate the orientation of the encapsulant 703 within the carrier, while other portions of the encapsulant 703 may not be visible within the carrier. Ensuring the direction of radiation shielding, for example, by using the protrusions 711, may facilitate quality control during manufacturing of the carrier with embedded seeds and encapsulant, and may facilitate medical quality control when medical personnel place the carrier in a patient and can quickly know the direction of radiation shielding.

[0149] In some embodiments, the protrusions 711 may be the same material as the rest of the encapsulant 703, e.g., a plastic or polymer, that remains in the tissue after the carrier is absorbed into the tissue, e.g., to reduce seed migration. In some embodiments, the protrusions 711 may extend into the carrier to be adjacent (or closer to) the embedded seeds, which may provide better seed migration control (before and after absorption of the carrier). In other embodiments, such as those discussed above with reference to FIG. 6, the protrusions 711 may include a bioabsorbable material, such as a material configured to be absorbed into the tissue at the same or a similar rate as the material of the carrier. In some embodiments, the protrusions 711 may include a high-Z material to provide additional radiation shielding. Exemplary Connector Embodiments

[0150] 8A illustrates an end view 810 and a cross-sectional view 811 of multiple exemplary encapsulants 803 (including encapsulants 803A and 803B) having a shielding layer 805 (including shielding layers 805A and 805B) and connected by an exemplary connector 808. As shown in cross-sectional view 811, encapsulants 803A and 803B are connected by connector 808. In some embodiments, more than two encapsulants 803 may be connected by connector 808, such as three encapsulants 803 connected by two connectors 808. Connector 808 may be the same material as encapsulant 803, such as a plastic or polymer. In this example, connector 808 is the same diameter as the encapsulants 803 to which it is connected.

[0151] In some embodiments, the connector 808 may be configured to carry a therapeutic agent, such as an antimicrobial agent. The connector 808 may carry the therapeutic agent in an interior area of ​​the connector 808 and may include one or more holes through which the therapeutic agent may diffuse to reach the tissue site of the patient. The connector 808 may be coated with the therapeutic agent.

[0152] In some embodiments, the connector 808 may include a sensor. For example, the connector 808 may include a pH meter configured to detect a pH level at the patient's tissue site, which may warn of a bacterial infection at the tissue site. In some embodiments, the sensor may be powered by a biological component at the patient's tissue site, such as ions of sodium, potassium, etc. In some embodiments, the connector 808 may biodegrade over time.

[0153] In some embodiments, the connector 808 may include indentations, or notches, or ribs 814. The ribs 814 may allow the connector 808 to bend while preventing the connector 808 from stretching, compressing, or twisting. Advantageously, the ribs 814 may allow the connector 808 to bend, facilitating placement of the carrier (with the connector 808 and encapsulant 803 embedded therein) over the uneven surface of a tumor bed without sacrificing structural durability or integrity.

[0154] In some embodiments, the connector 808 may include a high-Z material, such as a shielding layer, along an outer surface of the connector and / or in an interior section of the connector.

[0155] FIG. 8B illustrates an end view 820 and a cross-sectional view 821 of a plurality of exemplary encapsulants 813 (including encapsulants 813A and 813B), each having a shielding layer 815 (including shielding layers 815A and 815B), connected by an exemplary connector 818. In this example, the connector 818 has a smaller diameter than the encapsulants 813. In some embodiments, the connector 818 may have a diameter large enough to prevent stretching, compression, or twisting when a longitudinal or rotational force is applied to the connector 818, for example, when placing the encapsulant 813 and corresponding seed 301 on the carrier, as described with reference to FIGS. 10A-10B and 11. In some embodiments, the connector 818 may have a diameter small enough to allow the connector 818 to bend. For example, in implementations where the carrier is placed on a curved surface, the connector 818 may be configured to bend to allow the carrier to conform to a tissue site. In some embodiments, the connector 818 may be approximately 0.5 mm in diameter.

[0156] In some embodiments, connectors such as exemplary connectors 808 and 818 may include one or more magnetic resonance imaging (MRI) markers that are visible on magnetic resonance imaging. The MRI markers may allow the location of the connectors and / or encapsulated seeds to be visualized or referenced in post-operative MR images, for example, to confirm dosimetry. This may reduce or eliminate the need to perform additional imaging, such as a post-operative computed tomography (CT) scan to visualize the seeds and confirm dosimetry. The MRI markers may also facilitate placement of the encapsulated seeds during MRI-guided brachytherapy. Exemplary MRI markers may include gadolinium, iron oxide, iron platinum, manganese, protein, saline, Conray 60, copper sulfate, liquid vitamin E, fish oil, agarose gel, or cobalt chloride.

[0157] 9A-9C are end, side, and top views, respectively, of a plurality of exemplary encapsulants 903 having a shielding layer 915 and connected by exemplary connectors 908. As shown, in some embodiments, the connectors 908 may not have a circular cross-section. The connectors 908, or portions thereof, may extend beyond the seeds 301. As shown in FIG. 9B, the connectors 908 may extend deeper into the carrier 907 than the seeds 301, thus facilitating securing the encapsulants 903 and seeds 301 to the carrier 907. As shown in FIG. 9C, the encapsulants 903 and connectors 908 are visible at the top surface of the carrier 907. Thus, in some embodiments, the encapsulant 903 and / or connector 908 may be configured to extend partially out from the carrier (e.g., rather than being fully embedded as in some other embodiments discussed herein) to provide a visual cue to the user of the top (e.g., the shielded side from which the encapsulant extends) and bottom (the unshielded side that will be placed on the treatment surface of the patient). In some embodiments, the encapsulant 903 may be secured to the top (or other surface) of the carrier 907 using one or more fasteners, such as fasteners 609, 619 discussed with reference to FIG. 6.

[0158] 10A is a perspective view of an encapsulated seed assembly 1004 that includes multiple encapsulants 1003 (including encapsulants 1003A and 1003B) connected therebetween by multiple connectors 1008. As shown, a seed 301 is positioned within each encapsulant 1003. The encapsulants 1003 may include a shielding layer, for example, according to any of the exemplary embodiments discussed herein. In this example, the encapsulant 1003A includes protrusions 1011 on either side of the encapsulant 1003A that may reduce rotation and / or other movement of the encapsulant 1003A after it is placed in the carrier and maintain a constant orientation of the radiation shielding.

[0159] The encapsulant 1003 may be connected by connectors 1008. Additional connectors 1008 extend away from the end of the encapsulant 1003. One or all of the connectors 1008 may include protrusions 1012. For example, as shown, connector 1008A includes three protrusions 1012 that may further anchor the encapsulated seed assembly 1004 by reducing movement of the connector 1008A. In some embodiments, a portion of the encapsulated seed assembly 1004, such as a portion of the connector 1008A that includes protrusions 1012, may be positioned partially outside the carrier to provide a visual indication of the location and orientation of the encapsulated seed within the carrier. This may allow a manufacturer or medical personnel to know the direction of radiation shielding without having to view the entire encapsulated seed assembly 1004.

[0160] 10B is an end view 1020 and a cross-sectional view 1021 of an example implementation of a carrier 1007 with multiple encapsulated seeds embedded therein. In this example, multiple encapsulants (including encapsulants 1003A, 1003B, 1003C, and 1003D) are loaded with seeds 301, and the encapsulated seeds are connected to other encapsulated seeds by connectors 1008. The seeds 301, encapsulants 1003, and connectors 1008 may be fully embedded within the carrier 1007, as shown in FIG. 10B, or may be partially embedded within the carrier.

[0161] In this exemplary embodiment, the encapsulant 1003 includes a protrusion 1011 and some of the connectors 1008 include a protrusion 1012. The protrusions 1011 and 1012 may prevent the encapsulant 1003 and / or the connectors 1008 from rotating within the carrier 1007. This may prevent the orientation of the radiation shielding from changing relative to the carrier 1007 after the encapsulant 1003 is placed within the carrier 1007. As shown, the protrusion 1012 of the connector 1008A and the protrusion 1011 of the encapsulant 1003C are visible from the exterior of the carrier 1007, for example, as shown in end view 1020. For example, the protrusion 1011 or the protrusion 1012 may be flush with an end (or side) surface of the carrier 1007 to provide a visual indication of the location and / or orientation of the encapsulated seeds within the carrier. This allows the manufacturer or medical personnel to know the direction of radiation shielding without having to view the entire encapsulated seed assembly.

[0162] 10C is a top view of an exemplary encapsulated seed assembly 1022 positioned for insertion into a side of a carrier 1030 (e.g., between the top and bottom surfaces). In this example, multiple encapsulants 1023 are connected by connectors 1028. Although not shown in FIG. 10C, each of the encapsulants 1023 may be loaded with radioactive seeds using a process discussed elsewhere herein. The position-maintaining component of the encapsulated seed assembly 1022 comprises a cross member 1025 having an anchor 1026 that extends toward the carrier 1030. In this embodiment, the encapsulated seed assembly 1020 is sized and configured (e.g., the length of the connector 1028 is selected) such that the seeds are properly positioned within the carrier 1030 when the anchor 1026 is inserted into the side of the carrier 1030 (e.g., when the cross member 1025 abuts the proximal end 1031 of the carrier 1030). 10C , the dashed lines indicate a portion of the encapsulated seed assembly 1022 embedded within the carrier 1030. In this example, the radioactive seeds within the encapsulation 1023 are appropriately positioned within the carrier 1030 (e.g., according to a radiation treatment plan) with the cross member 1025 abutting the proximal end 1031 of the carrier 1030. In some embodiments, the cross member 1025 may have visual or tactile features that indicate the orientation of the encapsulation and / or seeds, for example, to indicate the direction in which shielding is provided by the encapsulation 1023 (which is not visible once the encapsulation 1023 is embedded within the carrier 1030).

[0163] 10C , the anchors 1026 secure the encapsulated seed assembly 1022 within the carrier 1030 by reducing movement of the encapsulated seed assembly 1022. In the example of FIG. 10C , the anchors 1026 include spikes, however, in other embodiments, the anchors 1026 may be any other type or configuration of anchoring mechanism, such as hooks. Additionally, the number of anchors 1026 may vary, for example, including fewer (e.g., one) or additional (e.g., three, four, five, etc.) anchors as part of the encapsulated seed assembly 1022.

[0164] 11 is a perspective view of an insertion device 1115 used to place an encapsulated seed assembly, including multiple encapsulants, connectors, and seeds, into a carrier. The insertion device 1115 may be connected to a connector 1108, which may then be connected to the encapsulant 1103 and / or the seed 301. The insertion device 1115 may include a distal tip 1117, which may be pointed or sharp. The insertion device 1115 may be inserted into the carrier via the distal tip 1117. The pointed distal tip 1117 may facilitate insertion into the carrier. The insertion device 1115 may be longer than the length of the side of the carrier in which the encapsulated seed assembly is to be placed, such that the insertion device may be pushed through the carrier from one side until the distal tip 1117 exits the carrier on the other side. Once the distal tip 1117 has been pushed completely through the carrier such that the distal tip 1117 exits the other side of the carrier, the distal tip 1117 may be pulled such that the insertion device 1115 is pulled through the entire carrier. This may also pull the adjacent encapsulated seed assembly into the carrier and at least partially through the carrier. The distal tip 1117 and / or the insertion device 1115 may be pulled until the entire encapsulated seed assembly is embedded within the carrier, or may be otherwise positioned relative to the carrier as needed or desired. In some embodiments, the distal tip 1117 and / or the insertion device 1115 may be pulled until the end of the connector 1108A is flush with the side of the carrier, as shown, for example, in FIG. 10B. Once the encapsulated seed assembly is positioned relative to the carrier as needed or desired, a portion of one or more of the connectors 1108 may be partially embedded within the carrier or may partially protrude from the carrier. For example, after the encapsulated seed assembly is positioned relative to the carrier as needed or desired, connector 1108A and / or connector 1108B may protrude partially from the carrier. Any portion of connector 1108 that protrudes from the carrier after insertion may be cut off so that the end of the connector is flush with the end of the carrier and so that no portion of the connector extends beyond the side of the carrier.In some embodiments, the portion of the encapsulant that protrudes from the carrier after positioning may also be cut as described above with reference to the connector. Additional embodiments.

[0165] In particular, conditional language such as "can," "could," "might," or "may," unless expressly stated otherwise or understood otherwise within the context in which it is used, is generally intended to convey that certain embodiments include certain features, elements, and / or steps, while other embodiments do not. As such, such conditional language is generally not intended to suggest that the features, elements, and / or steps are in any way required by one or more embodiments, or that one or more embodiments necessarily include logic that determines, with or without user input or prompts, whether those features, elements, and / or steps are included or should be performed in any particular embodiment.

[0166] It should be emphasized that many variations and modifications may be made to the above-described embodiment, and that the elements should be understood to belong to other acceptable examples. All such modifications and variations are intended to be included within the scope of the present disclosure herein. The above description details certain embodiments of the present invention. However, no matter how detailed the above description may appear in writing, it will be understood that the present invention can be implemented in many aspects. As mentioned above, the use of a particular term in describing a particular feature or aspect of the present invention should not be interpreted as suggesting that the term is redefined herein to be limited to include any inherent characteristics of the feature or aspect of the present invention with which the term is associated. Thus, the scope of the present invention should be interpreted according to the appended claims and any equivalents thereof.

Claims

1. 1. A carrier system for delivering directed radiation therapy to a tissue site in response to a dosimetry plan, comprising: a biocompatible carrier configured to be placed on an exposed treatment surface of a surgically created cavity in mammalian tissue; a plurality of shielded encapsulants each having a substantially cylindrically shaped device having a shielding layer comprising a high-z material, where each shielded encapsulant includes a central longitudinal cavity and a longitudinal opening to the cavity; a plurality of substantially cylindrical radioactive seeds positioned within the central longitudinal cavity of a corresponding shielded encapsulant, the longitudinal openings being sized to permit movement of the radioactive seeds within the central longitudinal cavity having an inner diameter substantially the same as an outer diameter of the radioactive seeds; and one or more connectors configured to secure and space respective pairs of shielded envelopes in response to the dosimetry plan; An encapsulated seed assembly having Equipped with A carrier system, wherein after the encapsulated seed assembly is inserted into the biocompatible carrier, the plurality of radioactive seeds are positioned within the biocompatible carrier according to the dosimetry plan.

2. 10. The carrier system of claim 1, wherein each of the shielding envelopes is configured to be attached to a corresponding radioactive seed by a snap fit or friction fit and to cover at least a portion of an outer surface of the radioactive seed.

3. The carrier system of claim 1 , wherein at least one of the shielded encapsulants includes one or more protrusions configured to secure the shielded encapsulant to the carrier.

4. The carrier system of claim 1 , wherein at least one of the shielded encapsulants includes one or more protrusions configured to increase rotational inertia to reduce rotation relative to the carrier.

5. The carrier system of claim 1 , wherein the shielding layer comprises a plurality of individual, separate layers of one or more high-Z materials.

6. The carrier system of claim 1 , wherein the shielding layer is embedded in an interior area of ​​the shielding device.

7. The carrier system of claim 1 , wherein the shielding layer is positioned on an outer surface of the shielding device.

8. The carrier system of claim 1 , wherein the shielding layer comprises two half-value layers (HVLs).

9. 10. The carrier system of claim 1, wherein the shielding encapsulant has a thickness between about 0.18 mm and 0.22 mm and the shielding layer has a thickness between about 0.026 mm and 0.036 mm.

10. The carrier system of claim 1 , wherein the shielding layer has a thickness between about 0.01 mm and 0.06 mm.

11. The carrier system of claim 1 , wherein the shielding encapsulant comprises a plastic or a polymer.

12. The carrier system of claim 1 , wherein the one or more connectors are cylindrical in shape and have a diameter of 0.5 mm.

13. The carrier system of claim 1 , wherein the one or more connectors comprise a therapeutic agent.

14. 2. The carrier system of claim 1, wherein at least one of the one or more connectors includes one or more protrusions visible from an exterior of the carrier to indicate a direction in which radiation emitted from the radioactive seed is shielded by the shielding layer.

15. The carrier system of claim 1 , wherein the carrier comprises collagen.

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