VOID OCCLUSION DEVICE.

Abstract

A void occlusion device is described, comprising a scaffold that defines a plurality of voids and a reinforcing element. The scaffold is configured to allow infiltration of human tissue into the plurality of voids. The reinforcing element extends through at least a portion of the scaffold and is configured to resist compressive forces exerted on the scaffold. Modalities in which the void occlusion device is biocompatible, bioresorbable, elastic, and radiologically suitable are also described.

Description

VOID OCCLUSION DEVICE Cross-reference to related application This application claims the benefit of the United States application serial number 17 / 078,940 filed on October 23, 2020. The disclosure of the foregoing is incorporated by reference as if fully recapitulated herein. Field of invention The application relates to void occlusion devices and, more particularly, to void occlusion devices that are bioresorbable and configured to occupy space in tissue voids. Background of the invention Approximately 300,000 people in the United States, 55,000 in the United Kingdom, and 1.8 million people worldwide are diagnosed with breast cancer annually. As a result, mastectomies are commonly performed to remove cancerous breast tissue (e.g., a tumor) before it can metastasize to the rest of the body. Mastectomy procedures involve the complete removal of a human breast, a massively invasive surgery that causes significant aesthetic / cosmetic changes for the patient. Furthermore, mastectomies typically require breast reconstruction surgery after the procedure to rebuild the breast. For this reason, many patients experience not only physiological trauma but also psychological trauma. As an alternative to mastectomies, lumpectomy procedures can also be performed, which involve removing only the tumor rather than the entire breast. This procedure allows the surgeon to preserve much of the breast, but it significantly alters the breast's shape due to the void created where the tumor used to be. The most common method for treating a lumpectomy is to surgically close the tumor void, with the breast's shape maintained postoperatively by the fluid-filled void. However, fluid drainage can cause the void to collapse, resulting in the breast developing cavities or losing volume, or the edges scarring together. This affects the breast's shape and often causes pain and impedes healing.An additional problem is the difficulty of precisely targeting the old tumor bed for postoperative radiotherapy, which is necessary to minimize the risk of recurrence, but has the unfortunate side effect of increasing the patient's risk of developing secondary cancer later in life. However, lumpectomy procedures are generally safer, faster, and more cost-effective than mastectomies. Despite this, more than 50% of breast cancer patients opt for mastectomies. One of the main reasons patients choose mastectomy over lumpectomy is the lack of preservation of the breast's aesthetic shape. Physicians also often favor mastectomy procedures because they allow for better targeting of postoperative radiation therapy. Consequently, experts in the field continue their research and development efforts in the area of ​​lumpectomy procedures. Brief description of the invention Void occlusion devices are disclosed that include a support, a plurality of voids in the support, and a reinforcing element. In one embodiment, the void occlusion device includes a scaffold that defines a plurality of voids and a reinforcing element. The scaffold is configured to allow the infiltration of human tissue into the plurality of voids. The reinforcing element extends through at least a portion of the scaffold and is configured to resist compressive forces exerted on the scaffold. In another embodiment, the void occlusion device includes a support and a reinforcing element. The support includes a large disc comprising a plurality of concentric rings arranged around a central point and a plurality of radial elements extending radially outward from the central point, wherein each radial element of the large disc intersects each concentric ring of the large disc. The support further includes a small disc comprising a plurality of concentric rings arranged around a central point and a plurality of radial elements extending radially outward from the central point, wherein each radial element of the small disc intersects each concentric ring of the small disc. Each of the large and small discs defines a radius, and the radius of the large disc is greater than the radius of the small disc. In another embodiment, the void occlusion device includes a support and a reinforcing element. The support includes a lattice structure that defines a plurality of voids, where the support is configured to allow the infiltration of human tissue into the plurality of voids. The reinforcing element extends through at least a portion of the support and is configured to resist compressive forces exerted on the support. Further examples of the disclosed vacuum occlusion device, and the method for manufacturing it, will become apparent from the following detailed description, accompanying drawings, and appended claims. Brief description of the drawings Figure 1 is a top perspective view of a first modality of the void occlusion device; Figure 2 is a top plan view of the vacuum occlusion device of Figure 1; Figure 3 is a side elevation view of the vacuum occlusion device of Figure 1; Figure 4 is a schematic illustration of the void occlusion device of Figure 1 being inserted into a void in a human sinus; Figure 5 is a top perspective view of a second modality of the void occlusion device; Figure 6 is a top plan view of the vacuum occlusion device of Figure 6; Figure 7 is a side elevation view of the vacuum occlusion device of Figure 6; Figure 8 is an alternative side elevation view of the vacuum occlusion device of Figure 6; Figure 9 is a side elevation view of a portion of the vacuum occlusion device of Figure 6; Figure 10 is a top perspective view of a third modality of the void occlusion device; Figure 11 is a top plan view of the vacuum occlusion device of Figure 11; Figure 12 is a side elevation view of the vacuum occlusion device of Figure 11; Figure 13 is an alternative side view of the vacuum occlusion device of Figure 11; Figure 14 is a side elevation view of a portion of the void occlusion device of Figure 11; and Figure 15 is an X-ray image showing two modalities of the void occlusion device obtained by conventional clinical imaging. Detailed description of the invention The following detailed description refers to the accompanying drawings, which illustrate specific examples described in this disclosure. Other examples with different structures and operations are not outside the scope of this disclosure. Similar reference numbers may refer to the same feature, element, or component in the different drawings. The following are illustrative, non-exhaustive examples that may, but are not necessarily, constitute claims of the subject matter of this disclosure. References to "examples" herein mean that one or more functions, structures, elements, components, features, and / or operating steps described in relation to the example are included in at least one embodiment and / or implementation of the subject matter of this disclosure. Thus, the phrase "an example" and similar wording throughout this disclosure may, but are not necessarily, refer to the same example. Furthermore, the subject matter characterizing any example may, but are not necessarily, include the subject matter characterizing any other example. With reference to Figure 1, this disclosure provides a modality of a void occlusion device 100 (hereinafter, the device) that can be used to assist in the cosmetic restoration of a human breast. When a void is created in a human breast, the device 100 can be implanted in that void to provide mechanical support to the overlying breast tissue (e.g., adipocytes, blood vessels, and other native cells), thereby maintaining the natural contour of the breast (e.g., size and shape). The device 100 includes a scaffold 10, comprising a porous structure, which allows infiltration of natural breast tissue into it (i.e., ingrowth). After a period of time, the device 100 can be degraded by the body (i.e., bioresorbable), leaving only natural breast tissue in the space where the void was previously located. Particularly in the context of lumpectomy procedures, the Device 100 can be useful for filling voids created by tumor removal (Figure 4). The device can be inserted during the same procedure after tumor removal. Doing so can facilitate breast healing without the risk of collapse or cavity formation, thus improving the patient's quality of life. Furthermore, given the bioresorbability of the Device 100, it is anticipated that little or no subsequent breast reconstruction would be required. In addition, as described below, the Device 100 can also assist in obtaining radiographs of the tumor site after lumpectomy. The Device 100 can be used similarly for breast augmentation and enhancement. Breast augmentation is typically performed by separating the breast tissue from the underlying musculature and connective tissue to create a cavity in front of or behind the pectoral muscle. A conventional breast implant (e.g., saline or silicone) is then inserted into the cavity, and the site is closed. In this case, the Device 100 can be inserted into the cavity like a conventional breast implant to achieve the patient's desired size and shape. Furthermore, the Device 100 is generally considered to offer several improvements over conventional breast implants. For example, because the Device 100 is primarily composed of a porous structure and does not contain saline or silicone gel, it can be less dense and lighter than conventional breast implants.Therefore, the risk of leakage is eliminated and the likelihood of sagging is minimized. Furthermore, since the 100 device is designed to be broken down by the body, leaving only natural breast tissue, the end result will be a breast that looks and feels more natural, if not completely natural. In contrast, conventional breast implants often feel different, which can cause problems with throbbing and even interfere with imaging during breast cancer screening tests. With reference to Figures 1-3, 5-9, and 10-14, this disclosure provides three non-limiting embodiments of the device. Each of these embodiments is discussed below. With reference to Figures 1-3, a first embodiment is shown. In this case, the device 100 includes a support 10 that defines a general cylindrical shape, composed of alternating units of small disks 20 and large disks 30 (Figure 3). These disks 20, 30 are arranged in a stacked configuration and aligned along their center points 22, 32. Each of the large disks 30 can include a plurality of concentric rings 34 (six are shown) connected by a plurality of radial elements 36 (sixteen are shown). The radial elements 36 can extend from the center point 32 to the outermost concentric ring 34. Furthermore, each concentric ring 34 can be incrementally larger than the immediately preceding concentric ring 34 (i.e., closer to the center point). The small disks 20 have a smaller radius than the large disks 30, but can otherwise be similar in configuration. That is, the small disks 20 can also include a plurality of concentric rings 24 (five are shown) connected by a plurality of radial elements 26 (sixteen are shown) extending radially outward from a central point 22. As arranged, the radial elements 26 can be aligned with the radial elements 36 of the large disks 30. Furthermore, the concentric rings 24 of the small disks 20 can be arranged in an offset arrangement relative to the concentric rings 34 of the large disks 30. As shown in Figure 2, when viewed from above, the concentric rings 24 of the small disks 20 can occupy the horizontal space between the concentric rings 34 of the large disks 30. Furthermore, the device may include a plurality of reinforcing elements 40 extending perpendicularly from the plane of each disk 20, 30. These reinforcing elements 40 may extend from where the concentric rings 24, 34 intersect with the radial elements 26, 36. In the embodiment shown, the reinforcing elements 40 are provided at each intersection of the concentric ring and the radial elements, and are generally equal in size and shape. As those skilled in the field will appreciate, the radial elements 26, 36 of the discs 20, 30 can resist the longitudinal compression 50 of the device 100 (Figure 3), while the reinforcing elements 40 resist the lateral compression 52 (Figure 2). In this way, the device 100 can prevent an empty sinus 58 from collapsing upon itself while providing the necessary support to maintain its shape (Figure 4). With reference to Figures 5-9, a second embodiment of Device 200 is shown. In this embodiment, Device 200 includes a support 60 comprising a uniform lattice structure 61. Each unit cell of the lattice structure 61 comprises a central portion 62 with six branching arms 64 and a pore 66 extending through the central portion 62 (Figure 9). The central portion 62 and the branching arms 64 can be curved such that circular channels 68 are defined throughout Device 200. In the embodiment shown, the circular channels 68 are defined from each Cartesian direction (X in Figure 7, Y in Figure 6, and Z in Figure 8). These channels 68 provide a clear pathway for the growth of new breast tissue within the device, thereby facilitating infiltration. In an exemplary embodiment, each unit cell can occupy a space of approximately 0.5 cubic millimeters to approximately 2.0 cubic millimeters. In addition, a reinforcing element 69 can also be provided to resist compression. In this case, the reinforcing element 69 comprises a spiral that extends through, and is integral with, the support 60. As those skilled in the art will appreciate, this spiral can resist lateral compressive forces 54 about the spiral axis A (Figure 7). Parallel forces 56 may encounter less resistance, which contributes to a softer feel. In one example, the reinforcing element 69 can have a spiral radius Ri of approximately 4 millimeters to approximately 40 millimeters. In another example, the reinforcing element 69 can have a spiral length Li of approximately 4 millimeters to approximately 40 millimeters. With reference to Figures 10-14, a third embodiment of device 300 is shown. This device 300 is similar to device 200 of the second embodiment in that it also includes a support 70 comprising a uniform lattice structure 71 and a spiral reinforcing element 79 extending through it. In one example, the reinforcing element 79 can have a spiral radius R? of approximately 4 millimeters to approximately 40 millimeters. In another example, the reinforcing element 79 can have a spiral length L3 of approximately 4 millimeters to approximately 40 millimeters. Furthermore, each unit cell of the third embodiment also includes a central portion 72 with six branching arms 74 and a pore 76 extending through the central portion 72 (Figure 14).However, the lattice structure 71 of the third mode 300 differs from the lattice structure of the second mode 200 in that the branching arms 74 and the central portions 72 are curved such that the channels 78 are provided only from one Cartesian direction (Y in Figure 11). As those skilled in the art will appreciate, orienting the central portions 72 in this way can enable the device to resist compressive forces parallel 56 to the axis of the spiral of the reinforcing element. The 100, 200, 300 device can be scaled, shaped, and / or combined as needed to accommodate voids of any size and shape. For example, the first modality 100 device can be enlarged to accommodate particularly large voids. In another example, the second modality 200 device can comprise a repeating unit in a larger void occlusion device. In yet another modality, the third modality 300 device can be cut (i.e., shaped) or manipulated by a clinician to match the shape of a void. Any of the principles illustrated in the three preceding examples can be applied to any of the three modality 100, 200, 300 devices. While the three device modalities described above (100, 200, 300) are exemplary, several other designs and configurations for the support and reinforcement element are contemplated and may be used without departing from the scope of this disclosure, provided that the general device 100 is sufficiently porous to infiltrate natural breast tissue. For example, porous, irregular designs that do not include a defined lattice structure composed of repeating unit cells may also be used. These designs may be preferable for modalities where the device 100 is fabricated from foam-based materials. By necessity, Device 100 must be manufactured from biocompatible (e.g., cytocompatible) materials. Otherwise, it may cause pain, discomfort, or worse for the patient, especially considering how Device 100 is intended to remain inside the patient long-term. Furthermore, the selected material must also exhibit bioresorption properties (i.e., the material will be absorbed by the body upon implantation rather than remaining inert at the implant site) to allow the patient to degrade Device 100 over time. Preferably, Device 100 can degrade slowly within the body over a period ranging from 12 to 48 months, but ideally from 18 to 24 months. Additionally, the material can also be 3D-printable to facilitate the fabrication of the complex lattice structures shown in Figures 1–14.In addition, the material can also be elastic, exhibiting low expansion force and preferably a tensile strength to failure ranging from 20% to nearly 300%, so that the device can be compressed before implantation, and then smoothly expand to fill the void and take the shape of the void without expanding or tearing the surrounding soft tissue (e.g., shape memory). The ideal material for lumpectomy and breast augmentation applications will be a soft, flexible polymer that can be processed using additive manufacturing (preferably compatible with the PCResink platform) or traditional manufacturing techniques. It should be able to withstand the deformations resulting from tissue distortion both during surgery and in daily life, and act as a tissue scaffold (chemical or inert guide) to allow healing to occur throughout the empty site, after which the device will degrade (via hydrolytic, enzymatic, or oxidative degradation). Additional ideal characteristics include radiovisibility, the ability to withstand sterilization, and the capacity to be processed as a composite, as well as the formulation of the original material. One example of a suitable material is aliphatic polycarbonate, which exhibits a low elastic modulus and elastomeric behavior, can be processed by digital light processing or stereolithography, and is suitable for tissue infiltration before slow degradation by surface erosion over the course of 18 to 24 months. A second suitable material would be aliphatic polyester, where sufficient crystalline content could be used to produce a flexible and resilient material capable of being 3D printed into a porous tissue support device that would slowly degrade as healing occurs. While the exact composition of such aliphatic polycarbonate and / or aliphatic polyester may vary without departing from the scope of this disclosure, a suitable material is generally considered to include, for example, polycarbonate linkages, diluents (e.g., reactive and / or nonreactive), and crosslinkers. Examples of suitable polycarbonate linkages may include, but are not limited to, phosphorus-ester linkages, polyester linkages, polyurethane linkages, amide linkages, urea linkages, sulfide linkages, disulfide linkages, dithioester linkages, thioester linkages, and / or a hydrocarbon backbone. Examples of suitable diluents may include functional groups such as, but are not limited to, thiols, alkynes, azides, cyclic carbonates, propylene carbonate, small-molecule epoxides, alkenes, thiols, and / or hybrid molecules containing any combination of the aforementioned functional groups.Examples of a suitable crosslinking agent may include, without limitation, a thiol crosslinking agent, multi-branched thiol crosslinking agents, and, most preferably, pentaerythritol tetrakis(3-mercaptopropionate). In another modality, a suitable material may include drug-derived monomers, such as a monomer derived from one or more of the following classes of non-steroidal anti-inflammatory drugs (NSAIDs): salicylates, propionic acid derivatives, acetic acid derivatives, enolic acid derivatives (oxicam), anthranilic acid derivatives (fenamates), selective COX-2 inhibitors, sulfonanilides, and others.Specific examples of NSAIDs found within these classes, which may be suitable for the purposes of this document, may include: aspirin (acetylsalicylic acid), diflunisal (Dolobid), salicylic acid and its salts, salsalate (Disalcid), ibuprofen, dexibuprofen, naproxen, fenoprofen, ketoprofen, dexketoprofen, flurbiprofen, oxaprozin, loxoprofen, indomethacin, tolmetin, sulindac, etodolac, ketorolac, diclofenac, aceclofenac, nabumetone, piroxicam, meloxicam, tenoxicam, droxicam, lornoxicam, isoxicam, phenylbutazone (Bute), mefenamic acid, meclofenamic acid, flufenamic acid, tolfenamic acid, celecoxib, rofecoxib, valdecoxib, parecoxib, lumiracoxib; etoricoxib, firocoxib, nimesulide, clonixine, licofelone, and / or 35 H-harpagod. In addition, the material may also include one or more photoinitiators so that the resulting composition is photocurable. An example of a suitable photoinitiator may include, without limitation, Irgacure (RTM) 784 (IUPAC name: Bis(.eta.5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1 Hpyrrol-1 -yl)-phenyl)titanium), an iodonium salt, a silyl or germane initiator (e.g. tris(trimethylsilyl)germane), tris(trimethylsilyl)silane (TTMS), Omnirad (RTM) 369 (IUPAC name: 2-benzyl-2dimethylamine-1-(4-morphol¡nophen¡l)-butanone-1), Irgacure (RTM) 819 (IUPAC name: bis(2,4,6 trimethylbenzoylj-phenylphosphineoxide), H-Nu 640 (RTM) (a cyanine borate photoinitiator available from Spectra Group Limited, Inc. 27800 Lemoyne Rd., Suite J Millbury, OH 43447) and / or Sylanto 7MP (a proprietary diaryliodonium salt with a hexafluorophosphate anion available from Synthos Specialties, Synthos Spólka Akcyjna, Chemików 1,32-600 Oswi^cim, Poland). With reference to Figure 15, which depicts two devices of the second modality (one device 200 with a coiled booster element 69 and the other device 200' without it), it is shown that the device design provides excellent radiovisibility when viewed by X-ray. In effect, the device 100 can be used as a target within the body to increase the accuracy of postoperative radiotherapy, thereby reducing the risk of secondary cancer formation caused by prolonged or undirected radiation exposure.By using the present invention as a visual target for medical radiotherapy, the precise area where cancerous tissue removed by lumpectomy can be treated can be targeted, while limiting radiation exposure outside that precise treatment area. This makes radiotherapy more effective by directing it to the exact area where the cancer was present, and safer for the patient by avoiding radiation exposure outside the precise area, or at least limiting radiation exposure beyond the area where the invention is located on the patient's body. Furthermore, it is further contemplated that the support and / or reinforcing element can be modified with materials such as metallic micro / nanoparticles or heavy atoms (e.g., iodine) to further enhance the radiovisibility of the device. The device, including the device modalities 100, 200, and 300 described above, can be manufactured using any suitable method, including, but not limited to, additive manufacturing. In a preferred embodiment, the device can be manufactured by formulating a polycarbonate resin, customizable by adjusting various compositions of oligomers, crosslinkers, reactive diluents, and chain extenders, and feeding the resin through a 3D printer to additively manufacture the device. Even more preferably, the resin can be a 4D polycarbonate resin ink (PCResink), ideally reproducible at a 1-liter scale, which is compatible with the PCResink platform. As those skilled in the field will appreciate, such a material is 3D printable and, at the same time, possesses the ability to change its shape in response to external stimuli.The PCResink platform may be capable of filling large voids without exerting substantial expansion forces that would distort soft tissues. Any embodiment of the present invention may include any of the features of the other embodiments of the present invention. The exemplary embodiments disclosed herein are not intended to be exhaustive nor to unnecessarily limit the scope of the invention. The exemplary embodiments were chosen and described to explain the principles of the present invention so that other people skilled in the art may practice the invention. Having shown and described exemplary embodiments of the present invention, those skilled in the art will realize that many variations and modifications can be made to the described invention. Many of these variations and modifications will provide the same result and will lie within the substance of the claimed invention. Therefore, the invention is intended to be limited only as indicated by the scope of the claims.

Claims

CLAIMS 1. A void occlusion device comprising: a breast implantable support defining a plurality of voids, wherein the support is configured to permit infiltration of human tissue into the plurality of voids; and a reinforcing element extending through at least a portion of the support, wherein the reinforcing element is configured to resist compressive forces exerted on the support.

2. The vacuum occlusion device according to claim 1, wherein the support comprises a biocompatible material.

3. The vacuum occlusion device according to any of the preceding claims, wherein the support is bioresorbable.

4. The vacuum occlusion device according to any of the preceding claims, wherein the support is X-ray visible.

5. The vacuum occlusion device according to any of the preceding claims, wherein the support comprises a deformation-to-failure ratio ranging from 20 to 300%.

6. The vacuum occlusion device according to any of the preceding claims, wherein the support comprises aliphatic polycarbonate oligomers.

7. The vacuum occlusion device according to any of the preceding claims, wherein the support is manufactured from a 3D printable polycarbonate.

8. The vacuum occlusion device according to any preceding claim, wherein the support comprises a lattice structure defining a plurality of channels extending through the lattice structure.

9. The vacuum occlusion device according to claim 8, wherein the lattice structure comprises a unit cell having a size between 0.5 and 2.0 cubic millimeters.

10. The vacuum occlusion device according to claims 8 and 9, wherein the plurality of channels comprises a first channel and a second channel, the first channel being orthogonal to the second channel.

11. The vacuum occlusion device according to claims 8-10, wherein the reinforcing element comprises a spiral.

12. The void occlusion device according to claims 1-7, wherein the support comprises: a large disk comprising a plurality of coplanar concentric rings and a plurality of radial elements, wherein the large disk defines a central point and the plurality of radial elements extends from the central point through at least one of the concentric rings; a small disk comprising a plurality of coplanar concentric rings and a plurality of radial elements, wherein the small disk defines a central point and the plurality of radial elements extends from the central point through at least one of the concentric rings; and wherein each of the large disk and the small disk defines a radius, and the radius of the large disk is greater than the radius of the small disk.

13. The vacuum occlusion device according to claim 12, wherein the large disk and the small disk are arranged in a stacked configuration and the center point of the large disk is aligned with the center point of the small disk.

14. The vacuum occlusion device according to claim 13, wherein the concentric rings of the large disc and the concentric rings of the small disc are offset from each other.

15. The void occlusion device according to claims 12-14, wherein the reinforcing element extends perpendicularly between the large disc and the small disc.

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