Patent Publication Number: US-11642207-B2

Title: Size adjustable device to cover and secure implantable devices in surgical applications

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of nonprovisional patent application Ser. No. 16/515,142, filed in the United States Patent Office on Jul. 18, 2019, which is a nonprovisional filing of provisional patent application, Ser. No. 62/809,135, filed in the United States Patent Office on Feb. 22, 2019, claims priority therefrom, and is expressly incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to a device for preparing implantable devices for use in surgical applications. More particularly, the present disclosure relates to a size adjustable dermal matrix cover for enveloping an implantable device prior to implantation. 
     BACKGROUND 
     Implantable devices, such as breast implants and tissue expanders, require coverage with host tissue at the site of implantation, or coverage with a dermal or synthetic skin tissue matrix. Implantable devices also require stabilization at the site of host implantation to prevent the devices from shifting after implantation. Implantable devices cannot be sewn directly to host tissue without damage to the shell of the implantable device. Therefore, stabilization is often achieved by encasing the implantable device with implantable matrix material, such as acellular dermal matrixes, or by elevating host muscle and fascia. However, elevation of host fascia and muscle causes significant pain and disability in patients. 
     Acellular dermal matrixes are currently being used to both cover and stabilize breast implants or tissue expanders on the patient&#39;s chest wall by sewing multiple strips of usually square, rectangular or oval shaped devices to each other and then to the chest wall surrounding the implant or tissue expander. This practice of using multiple strips of dermal matrix has several important disadvantages. First, this practice results in significant wastage of expensive matrix material, and leads to increased preparation time within the operating room. Secondly, joining the different pieces of matrix results in palpable suture lines in the finished reconstruction. These suture lines may trigger false alarms in the future, leading to unnecessary imaging, tests, and biopsies. 
     There is also a possibility of lateral chest wall nerve entrapment. A suture line on the lateral aspect of the implant enclosure is necessary to prevent implant migration into the axillary area. However, a suture line which inadvertently runs across nerves which are superficial and abundant in this area, can lead to acute as well as chronic pain. In addition, changes in the dimensions of the implant pocket secondary to loosening of chest wall sutures can lead to implant malposition over time, resulting in revision surgeries for repositioning the implant. 
     Furthermore, this practice increases the risk of a needle puncture of the implantable device occurring during suture stabilization of the dermal matrix sheets to the chest wall. A needle puncture can lead to a rupture of the implantable device, requiring an otherwise avoidable surgical procedure to replace the damaged implantable device. 
     Finally, implantable devices vary widely in shape and size. For example, the implantable devices used in breast surgery are spherical or conical. Thus the practice of covering implantable devices using a patchwork of multiple pieces of dermal matrix continues, as it would be cost prohibitive to produce matrix covers uniquely configured to cover each type of implantable device. 
     Clearly, there is a need for an improved implantable matrix cover suitable for encasing implantable devices with varying dimensions, which addresses the problem of palpable suture lines causing nerve entrapment, and further avoids the use of stabilization methods which can cause needle punctures in the implantable device. 
     In the present disclosure, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which the present disclosure is concerned. 
     While certain aspects of conventional technologies have been discussed to facilitate the present disclosure, no technical aspects are disclaimed and it is contemplated that the claims may encompass one or more of the conventional technical aspects discussed herein. 
     BRIEF SUMMARY 
     An aspect of an example embodiment in the present disclosure is to provide a cover formed from a single piece of two-dimensional implantable matrix material with minimal wastage, which is capable of encasing an implantable device for use in a surgical procedure. Accordingly, the present disclosure provides a circular cover formed of implantable matrix material having an outer circle and a concentric inner circle. The outer circle is formed from a plurality of fringes which radiate circumferentially from the inner circle. The implantable device is placed upon the inner circle, while the fringes fold inwardly to form an overlapping implant pocket which fully envelops or encases the implantable device. 
     It is another aspect of an example embodiment in the present disclosure to provide a cover which can be stabilized at a site of host implantation without risk of puncturing the implantable device. Accordingly, the present disclosure provides a cover having a plurality of integral stabilization tabs which radiate from the inner circle after the overlapping implant pocket is formed, allowing the cover and the implanted device to be stabilized and centered at the site of host implantation via the stabilization tabs. 
     It is yet another aspect of an example embodiment in the present disclosure to provide a cover which envelops the implantable device without creating palpable suture lines which appear on medical imaging or which can entrap nerves. Accordingly, the present disclosure provides a cover with a punched opening on each of the plurality of fringes, allowing a loop of suture thread to be threaded circumferentially through each fringe while the cover lies flat and open, whereby the loop is tightened to pull the fringes inwardly to envelop the implantable device and form the overlapping implant pocket. 
     It is a further aspect of an example embodiment in the present disclosure to provide a cover which can be adjusted to the dimensions of the implantable device. Accordingly, the present disclosure provides a cover with fringes having fringe tips which can be trimmed in length to adjust for the diameter of the implantable device. 
     The present disclosure addresses at least one of the foregoing disadvantages. However, it is contemplated that the present disclosure may prove useful in addressing other problems and deficiencies in a number of technical areas. Therefore, the claims should not necessarily be construed as limited to addressing any of the particular problems or deficiencies discussed hereinabove. To the accomplishment of the above, this disclosure may be embodied in the form illustrated in the accompanying drawings. Attention is called to the fact, however, that the drawings are illustrative only. Variations are contemplated as being part of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, like elements are depicted by like reference numerals. The drawings are briefly described as follows. 
         FIG.  1    is a diagrammatic perspective view of a size adjustable cover formed of an implantable matrix material, such as acellular dermal matrix, in accordance with an embodiment in the present disclosure. 
         FIG.  2    is a diagrammatic perspective view of the size adjustable cover, showing an overlapping implant pocket formed from a plurality of radially projecting fringes, in accordance with an embodiment in the present disclosure. 
         FIG.  3    is a diagrammatic perspective view of the size adjustable cover, depicting an inner circle from which the fringes radiate, and an outer circle formed by the fringes, further showing an implantable device positioned upon the inner circle, in accordance with an embodiment in the present disclosure. 
         FIG.  4    is a diagrammatic perspective view of the size adjustable cover, depicting openings on each fringe through which a suture thread passes, in accordance with an embodiment in the present disclosure. 
         FIG.  5    is a diagrammatic perspective view of a cover die cutter for cutting dermal material to form the size adjustable cover, in accordance with an embodiment in the present disclosure. 
         FIG.  6    is a diagrammatic perspective view of the cover die cutter with optional inner circular blades, in accordance with an embodiment in the present disclosure. 
         FIG.  7    is a diagrammatic top view of the size adjustable cover lying flat and open, in accordance with an embodiment in the present disclosure. 
         FIG.  8    is a diagrammatic top view of the size adjustable cover, showing the plurality of fringes being linked together by the suture thread passing circularly through the openings of the fringes to form a loop, in accordance with an embodiment in the present disclosure. 
         FIG.  9    is a diagrammatic top view showing the implantable device placed upon the inner circle once the plurality of fringes have been linked together, in accordance with an embodiment in the present disclosure. 
         FIG.  10    is a diagrammatic perspective view of the size adjustable cover, showing the suture thread being drawn through the openings using a needle, in accordance with an embodiment in the present disclosure. 
         FIG.  11    is a diagrammatic perspective view of the size adjustable cover, showing the loop being tightened in a purse-string fashion to create the overlapping implant pocket which covers the implantable device, in accordance with an embodiment in the present disclosure. 
         FIG.  12    is a diagrammatic perspective view of the size adjustable cover, showing the overlapping implant pocket formed from fringes having a longer length, in accordance with an embodiment in the present disclosure. 
         FIG.  13    is a diagrammatic perspective view showing the overlapping arrangement of the fringes which form the overlapping implant pocket, in accordance with an embodiment in the present disclosure. 
         FIG.  14    is a diagrammatic cross section view of the implantable device enveloped within the size adjustable cover positioned at the site of implantation, whereby the implantable device is placed over the chest wall of a patient in a pre-pectoral position, further showing anchoring tabs which are attached to the chest wall to stabilize the implantable device, in accordance with an embodiment in the present disclosure. 
     
    
    
     The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, which show various example embodiments. However, the present disclosure may be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein. Rather, these example embodiments are provided so that the present disclosure is thorough, complete and fully conveys the scope of the present disclosure to those skilled in the art. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIGS.  1  and  2    illustrate a size adjustable cover  10  adapted to envelop an implantable device  80  used in a surgical application. Turning briefly to  FIGS.  3  and  14    while continuing to refer to  FIGS.  1  and  2   , in a preferred embodiment, the implantable device  80  is a spherical or conical device such as a breast implant or tissue expander employed for augmenting or reconstructing breast tissue  84 . Returning to  FIGS.  1  and  2    while also referring to  FIG.  7   , the size adjustable cover  10  comprises a sheet of acellular dermal matrix  12  formed in a two dimensional circular shape having an inner circle  20  and an outer circle  22  which are concentric. The inner circle  20  and the outer circle  22  have an inner circle circumference  20 C and an outer circle circumference  22 C respectively. The inner circle  20  has an inner circle inner face  21 A and an inner circle outer face  21 B disposed opposite thereof. The dermal matrix  12  may be synthetic, human or animal derived, or a combination thereof. Furthermore, the dermal matrix  12  may be substituted with any two-dimensional implantable matrix material known to a person of ordinary skill in the art in the field of the invention, which is suitable for reinforcing soft tissue in the surgical application for which the implantable device  80  is to be employed. 
     The cover  10  further has a plurality of fringes  14  which radiate outwardly from the inner circle circumference  20 C. In a preferred embodiment, a plurality of radial cuts  28  divide the dermal matrix  12  from the inner circle circumference  20 C and the outer circle circumference  22 C to form the fringes  14 . The plurality of fringes  14  are arranged circumferentially around the inner circle circumference  20 C and collectively form the outer circle  22 , and each fringe  14  has a fringe tip  14 T which is coextensive with a portion of the outer circle circumference  22 C. 
     Referring to  FIGS.  2 ,  3 , and  7   , the implantable device  80  is positioned upon the cover  10  above the inner circle inner face  21 A. The plurality of fringes  14  are folded inwardly towards a center point  18  of the inner circle inner face  21 A, and collectively form an overlapping implant pocket  30  which envelops and encases the implantable device  80 . The plurality of fringes  14  are linked together by a loop  44  of suture thread  40  which passes through an opening  24 B formed in each fringe. Referring to  FIGS.  1  and  2   , any of the fringes  14  which are not folded inwardly to form the overlapping implant pocket  30  may instead each constitute a stabilization tab  16 . 
     Turning back to  FIG.  14   , the implantable device  80  enveloped within the cover  10  may then be placed by a surgeon at a site of host implantation  110 . In a preferred embodiment, the surgical application is breast surgery and the site of host implantation  110  corresponds to a chest wall  82  of a patient. The cover  10 , along with the implantable device  80  enveloped within, is positioned against the chest wall  82 , with the overlapping implant pocket  30  facing towards the chest wall  82  and the inner circle outer face  21 B facing away from the chest wall  82 . The stabilization tabs  16  which radiate outwardly may be attached directly to the chest wall  82  to anchor the cover  10  and the implantable device  80  at a correct implant position. The cover  10  and the implantable device  80  are placed beneath the breast tissue  84  and skin flaps  86 . 
     The use of the cover  10  and the stabilization tabs  16  greatly facilitates revision surgeries by making adjustments of the skin flaps  86  unnecessary. By using the stabilization tabs  16 , the surgeon is able to anchor the implantable device  80  directly to the desired position on the chest wall  82  rather than modifying the skin envelope around the implantable device  80  to ensure correct implant position. This approach greatly reduces postoperative pain and opioid use. The invention greatly facilitates breast reconstruction surgeries by allowing the implantable devices  80  to be placed in a pre-pectoral fashion. The cover  10  and the implantable device  80  may be positioned above pectoral muscle  82 B located on the chest wall  82 , instead of below the pectoral muscle  82 B. The use of this technique greatly reduces postoperative pain in the long and short run and will facilitate the avoidance of opioid use in the postoperative setting. 
     Turning now to  FIG.  5    while also referring to  FIG.  7   , the cover  10  is manufactured using a cover die cutter  50  which is used to cut and shape the dermal matrix  12 . The use of the cover die cutter  50  allows the cover  10  to be produced in accordance with current FDA and other regulatory approvals, as the dermal matrix  12  differs from existing acellular dermal matrixes only in the use of the cutter  50  to shape the dermal matrix  12  in the patterns described herein. The cover die cutter  50  comprises an outer circular blade  56  adapted to cut the outer circle  22 , a plurality of fan shaped blades  58  adapted to create the radial cuts  28  that define the fringes  14 , as well as a plurality of hole punches  52  arranged in concentric rows which adapted to perforate the dermal matrix  12  to create the openings  24 A and/or inner openings  24 B for each fringe  14 . In an example embodiment, the openings  24 A or inner openings  24 B may have a diameter of one millimeter. Referring to  FIG.  6    while also referring to  FIGS.  5  and  7   , the cover die cutter  50  may further comprise one or more inner circular blades  54  which are concentric with the outer circular blade  56 . The inner circular blade  54  may be used to score rather than cut the dermal matrix  12  to define the inner circle  20  and the inner circle perimeter  20 C. Scoring the inner circle perimeter  20 C facilitates the folding of the fringes  14 . Furthermore, referring to  FIGS.  5 - 7    along with  FIG.  2   , the fan shaped blades  58 , the inner and outer circular blades  54 ,  56 , and the hole punches  52  may be retractable to allow for variation in the number of fringes  14  and stabilization tabs  16 . For example, stabilization tabs  16  may be cut without openings  24 A or inner openings  24 B. In an example embodiment, the cover  12  may have a diameter of approximately twenty-five centimeters as measured between the outer circle circumference  22 C. The inner circle  20  may have a diameter which is approximately one third the diameter of the outer circle  22 . Note that the example dimensions provided are not limiting, and the cover  10  may be provided in any size to suit the dimensions of the implantable device  80  and the requirements of the surgical application. Furthermore, the cover die cutter  50  is adapted to cut any alternative implantable matrix material suitable for use in the surgical application, as can be appreciated by a person of ordinary skill in the field of the invention and in adherence with the principles of the present disclosure. 
     Referring to  FIGS.  2 ,  3 , and  4    while also referring to  FIG.  7   , the opening  24 A of each fringe is disposed between the fringe tip  14 T and the inner circle circumference  20 C, while the inner opening  24 B is positioned between the opening  24 A and the inner circle circumference  20 C. Several of the plurality of fringes  14  are linked together by the loop  44  of suture thread  40  passing circularly around the cover  10  and through the opening  24 A of each fringe  14  which is used to form the overlapping implant pocket  30 . For example, the suture thread  40  may pass through several of the fringes  14  in an alternating sequence whereby every other fringe  14  is excluded from the loop  44 . Each excluded fringe  14  may therefore be used as one of the stabilization tabs  16 . Note that any number of stabilization tabs  16  may be created by excluding any of the fringes  14  from the loop  44 . 
     Turning now to  FIGS.  7 ,  8 , and  9   , when performing the surgical procedure, the cover  10  is unpacked from its sterile package and then soaked in sterile saline solution. The surgeon then selects and places the implantable device  80  upon the inner circle  20 , oriented in relation to the center  18  of the inner face  21 A. The surgeon then forms the loop  44  by threading the suture thread  40  through the openings  24 A of several of the fringes. As shown in  FIG.  10   , the threading can be performed using a needle  42 . Referring to  FIGS.  9 ,  10 , and  11   , the loop  44  is complete once all the fringes  14  selected to form the overlapping implant pocket  30  are linked together via the suture thread  40 . Alternatively, the threading may be performed before the implantable device  80  is placed upon the inner circle  20 . 
     Referring to  FIGS.  9 ,  11 , and  12   , the fringes  14  or tabs  16  may be trimmed to adjust the size of the overlapping implant pocket  30  to adapt to implantable devices  80  of different dimensions. A circular implantable device  80 , such as a breast implant, may have a diameter  80 D and a central point  80 C. Each fringe  14  may be cut or trimmed between the fringe tip  14 T and the inner circle circumference  20 C in order to shorten the length of the fringe  14  and create a new fringe tip  14 T at the location of the cut. The inner opening  24 B is positioned proximate to the inner circle circumference  20 C, allowing the fringe  14  to be linked to the suture thread  40  when cut short anywhere between the fringe tip  14 T and the inner opening  24 B, allowing the overlapping implant pocket  30  to envelop a smaller implantable device  80  with a smaller diameter  80 D. Fringes  14  which have not been trimmed (as shown in  FIG.  12   ), allow the overlapping implant pocket  30  to envelop a larger implantable device  80 . Referring to  FIGS.  9 ,  10 ,  11 , and  12   , the length of the fringes  14  can be adjusted so that the fringe tips  14 T of the plurality of fringes  14  meet at the central point  80 C of the implantable device  80  when drawn together to form the overlapping implant pocket  30 . Note that the loop  44  may be threaded through either the openings  24 A or the inner openings  24 B depending on the desired length of each fringe  14  as measured from the inner circle circumference  20 C to the fringe tip  14 T. For example, each fringe  14  may be cut to remove the opening  24 A, while leaving the inner opening  24 B which is disposed proximate to the inner circle circumference  20 C. 
     Each fringe  14  has a fringe inner face  14 F oriented in the same direction as the inner circle inner face  21 A, and a fringe outer face  14 H positioned opposite thereof. The threading may be performed using a consistent threading pattern by inserting the suture thread  40  through the opening  24 A of each fringe  14 , passing through the fringe inner face  14 F, and then drawing the suture thread  40  away from the fringe outer face  14 H. The threading pattern is repeated in either a clockwise or counterclockwise direction circumferentially around the cover  10 . 
     Referring to  FIGS.  9 ,  11 , and  13   , the suture thread  40  has two thread ends  40 E. To create the overlapping implant pocket  30 , the surgeon may pull each thread end  40 E to tighten the loop  44  in a purse-string manner and cause the plurality of fringes  14  to fold inwardly towards the inner circle inner face  21 A in an overlapping configuration to envelop the implantable device  80 . Each fringe  14  folds inwardly about the inner circle circumference  20 C, which may be scored to facilitate the folding. The stabilization tabs  16  continue to radiate outwardly from the inner circle circumference  20 C. In a preferred embodiment, each fringe  14  is overlapped by the fringe  14  either immediately preceding it or following it in the threading pattern (as shown in  FIG.  13   ). In certain embodiments where the fringes  14  are of sufficient length, the fringe tips  14 T of the plurality of fringes  14  are drawn together at the central point  80 C of the implantable device  80 , thus causing the entirety of the implantable device  80  to be enveloped within the overlapping implant pocket  30 . The thread ends  40 E may be tied together to secure the loop  44  and prevent the fringes  14  from separating. 
     Turning now to  FIG.  14    while continuing to refer to  FIG.  11   , once the implantable device  80  is enveloped within the overlapping implant pocket  30 , the cover  10  and the implantable device  80  is placed against the chest wall  82  at the site of host implantation  110 , with the inner circle outer face  21 B facing away from the chest wall  82 . In one embodiment, the site of host implantation  110  may be a defect created by a mastectomy and the removal of breast tissue  84 . The cover  10  and the implantable device  80  enveloped within may be stabilized by attaching the stabilization tabs  16  to the chest wall  82  using sutures, staples, or other attachment means. As the stabilization tabs  16  are integral with the cover  10 , it is unnecessary to suture the tabs to the cover  10 , thereby avoiding the possibility of accidentally puncturing the implantable device  80  during stabilization. Any unused or extra stabilization tabs  16  may be trimmed or removed. Once the cover  10  has been secured, the skin flaps  86  may be draped over the cover  10  and the implantable device  80  enveloped within to create a newly reconstructed breast mount  88 . 
     Note that the cover  10  may be employed for implantable devices  80  and surgical applications other than breast reconstruction. For example, the cover  10  may be employed for soft tissue reinforcement, and the stabilization tabs  16  may be used to secure the cover  10  to any site of host implantation  110 . 
     It is understood that when an element is referred hereinabove as being “on” another element, it can be directly on the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. 
     Moreover, any components or materials can be formed from a same, structurally continuous piece or separately fabricated and connected. 
     It is further understood that, although ordinal terms, such as, “first,” “second,” “third,” are used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, “a first element,” “component,” “region,” “layer” or “section” discussed below could be termed a second element, component, region, layer or section without departing from the teachings herein. 
     Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, are used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. It is understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     Example embodiments are described herein with reference to cross section illustrations that are schematic illustrations of idealized embodiments. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, example embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein, but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Moreover, sharp angles that are illustrated may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the present claims. 
     In conclusion, herein is presented a size adjustable cover for enveloping an implantable device in a surgical application. The disclosure is illustrated by example in the drawing figures, and throughout the written description. It should be understood that numerous variations are possible, while adhering to the inventive concept. Such variations are contemplated as being a part of the present disclosure.