Wound dressing for applying negative pressure to a wound and wound treatment system.

Abstract

Negative pressure wound dressing. The present invention relates to a multi-layered wound dressing for applying negative pressure to a wound. The dressing comprises a bioabsorbable layer, to be placed in contact with the wound; an occlusive outer layer impermeable to fluids; a fluid-porous carrier layer positioned between the outer layer and the bioabsorbable layer; and a fluid conduit in fluid communication with the carrier layer, to couple to a negative pressure source. The carrier layer comprises a multiplicity of fluid passages between the conduit and the bioabsorbable layer to allow fluid transfer through the dressing and bioabsorbable layers. The bioabsorbable layer comprises a plurality of openings to allow exudate to flow from the wound to the carrier layer.

Description

1 / 51 Wound dressing for applying negative pressure to a wound and wound treatment system. FIELD OF THE INVENTION

[001] The present invention relates to a wound dressing, in particular to a dressing for the application of negative pressure and / or for the instillation of treatment fluids into a wound. BACKGROUND OF THE INVENTION

[002] The technique of applying negative pressure in order to enhance healing in soft tissues has been used for many years with the main principle of the therapy remaining virtually unchanged.

[003] In the context of open wound treatment, negative pressure wound therapy (NPWT) typically involves placing porous materials, such as open-cell foam, reticulated foam, or gauze, at the wound site, sealing the wound cavity with an occlusive layer, and applying negative pressure to the sealed wound environment (see Figures 1 and 2). The clinical efficacy of this treatment is well supported in areas such as acute and chronic wounds, which has demonstrated accelerated granulation tissue formation in open wounds in response to treatment.

[004] Although the open architecture of the porous layer in contact with the wound allows for the effective application of pressure to the wound and the removal of wound exudate, a drawback with current NPWT dressing constructions is the susceptibility of healing granulation tissue to grow within the porous layer in contact with the wound. This results in trauma to the newly formed tissue when the foam layer is removed. To prevent or minimize this tissue growth, regular dressing changes are necessary, requiring additional time and expense. Furthermore, repeated dressing changes can induce acute trauma around the wound or cause the intact skin area at the periphery of the wound to also become granulated. Petition 870260051284, dated 05 / 28 / 2026, p. 7 / 129 2 / 51 the total treatment time.

[005] Collagen support structures, extracellular matrices, and tissue graft materials provide other useful means of promoting tissue growth and tissue regeneration in wounds. These bioabsorbable collagen-based materials contain biophysical and biochemical elements that support tissue regeneration through the various healing stages. The properties of collagen materials within these support structures can vary widely, which is largely attributed to variant xenogeneic or allogeneic origins and the different processing methods used during manufacturing.

[006] Collagen is a resorbable structural protein with a high affinity for water, and thus, collagen scaffolds can draw water out through the material's fine pores. Therefore, the use of these materials is primarily limited to the treatment of wounds with low levels of wound exudate. The fluid retained within the scaffold can prevent cell migration and proliferation, which may inhibit effective incorporation into the wound. In the context of NPWT, these materials present a substantial barrier to the passage of negative pressure to the wound interface, with the associated pressure drop resulting in ineffective NPWT treatment.

[007] One objective of the less preferred embodiments of the present invention is to eliminate one of the aforementioned disadvantages and / or at least offer the public a useful alternative.

[008] In this Descriptive Report, reference is made to patent descriptive reports, other external documents or other sources of information, and this is generally intended to provide context for discussing the characteristics of the invention. Unless specifically indicated otherwise, reference to such external documents or sources of information should not be interpreted Petition 870260051284, dated 05 / 28 / 2026, page 8 / 129 3 / 51 as the admission that such documents or sources of information, in any jurisdiction, consist of prior art or form part of the common general knowledge in the state of the art. SUMMARY OF THE INVENTION

[009] In a first aspect, the invention largely consists of a wound dressing for applying negative pressure to a wound, wherein the dressing comprises: a bioabsorbable layer to be placed in contact with the wound; an occlusive outer layer impermeable to liquids; a fluid-porous carrier layer positioned between the outer layer and the bioabsorbable layer; and a fluid conduit in fluid communication with the carrier layer, for coupling to a source of negative pressure; wherein the carrier layer defines a multiplicity of passages for fluids between the conduit and the bioabsorbable layer; and wherein the bioabsorbable layer comprises a plurality of openings or slits to allow fluid flow from the wound to the carrier layer.

[0010] The bioabsorbable layer may comprise a plurality of mechanically interlocked bioabsorbable sheets. The bioabsorbable layer may have a first sheet that has a plurality of lugs and a second sheet that has a plurality of openings, and each lug of the first sheet is situated through a respective opening in the second sheet in order to interlock the first sheet with the second sheet.

[0011] In one embodiment, the bioabsorbable sheets comprise the extracellular matrix (ECM). The ECM may comprise a reticulum.

[0012] In one embodiment, the bioabsorbable layer comprises a plurality of openings, and the openings define passages for fluids.

[0013] In one embodiment, the openings comprise two crossed notches to form a transverse shape and to define one or more fins in the bioabsorbable layer, wherein the fins are movable to Petition 870260051284, dated 05 / 28 / 2026, page 9 / 129 4 / 51 increase the size of the opening provided by each opening. The notches may have substantially an X shape, a Y shape, a C shape, a U shape, or a V shape.

[0014] In one embodiment, openings are formed through the bioabsorbable layer by removing a wad of material from the bioabsorbable layer.

[0015] In one embodiment, the bioabsorbable layer comprises a plurality of slits that define said passages for fluids, wherein each slit defines one or more fins in the bioabsorbable layer, wherein the fins are movable to increase the size of the opening provided by the slit. The slits may substantially have an X shape, a Y shape, a C shape, a U shape, or a V shape.

[0016] In one embodiment, slits or notches are cut into a matrix from the bioabsorbable layer.

[0017] Preferably, the slots or notches define the fins that allow the opening to open under pressure.

[0018] In one embodiment, the carrier layer is compliant and porous. For example, the carrier layer may comprise a fluid-permeable foam, such as a PVA (polyvinyl alcohol) foam.

[0019] In one embodiment, the upper surface of the carrier layer is wavy.

[0020] The carrier layer may include a microbicidal treatment.

[0021] In one embodiment, the dressing also comprises a pressure distribution layer between the carrier layer and the occlusive layer. The pressure distribution layer may comprise an open-cell foam or a three-dimensional fabric.

[0022] In one embodiment, the pressure distribution layer Petition 870260051284, dated 05 / 28 / 2026, page 10 / 129 5 / 51 comprises a plurality of fluid flow channels that are substantially perpendicular to the interface between the foam layer and the pressure distribution layer to allow fluid to flow through the pressure distribution layer.

[0023] In one embodiment, the conduit comprises a distally end portion that has an opening in fluid communication with the carrier layer.

[0024] In one embodiment, the distal end portion of the canal has a substantially arched shape.

[0025] In some forms, the conduit comprises a double lumen conduit comprising a support positioned along a central axis of one of the lumens to prevent the conduit from collapsing under compression.

[0026] Optionally, the conduit comprises a lumen that has an elliptical shape.

[0027] In one embodiment, the conduit is a double-lumen conduit comprising a primary conduit for applying negative pressure to the dressing and a secondary conduit for introducing fluid into the dressing or for facilitating pressure measurement.

[0028] In one embodiment, the dressing also comprises a sleeve comprising a port for receiving a portion of the conduit in the same in a secure arrangement for attaching the conduit to the dressing. The sleeve may comprise an elastomeric material.

[0029] In some modalities, the glove forms a divider between a negative pressure reception area of ​​the dressing and an ambient pressure area.

[0030] In one embodiment, the occlusive layer comprises a substantially transparent region and the carrier layer comprises one or more viewing openings below the transparent region to permit visual inspection of at least a portion of the Petition 870260051284, dated 05 / 28 / 2026, page 11 / 129 6 / 51 bioabsorbable layer.

[0031] In one embodiment, the occlusive layer comprises a polyurethane sheet having an adhesive surface.

[0032] In one embodiment, the wound dressing comprises a moldable adhesive seal to encircle a wound, wherein the seal comprises butyl rubber, a filler, and a tackifying resin. Preferably, the seal is removable and resealable against a patient's skin. In some embodiments, the seal is not resealable. In some embodiments, the seal is removable from the skin surface by stretching the adhered seal.

[0033] In a second aspect, the invention largely consists of a moldable and removable adhesive seal for surrounding a wound, and the seal comprises a butyl rubber, a filler and a tackifying resin.

[0034] In one embodiment, the seal is repositionable and deformable.

[0035] In one instance, the fence is not curable.

[0036] In one embodiment, the seal is removable from the skin surface by stretching the adhered seal.

[0037] In a third aspect, the invention largely consists of an adhesive seal application system comprising the moldable adhesive seal described in relation to the second aspect, and also comprising a first removable release sheet adhered to one side of the adhesive seal and a second removable release sheet adhered to the second side of the adhesive seal, wherein the second removable release sheet is stretchable.

[0038] In one embodiment, the second removable release sheet comprises silicone. Optionally, the removable protective sheet adheres to the second removable release sheet.

[0039] In some forms, the first removable release sheet Petition 870260051284, dated 05 / 28 / 2026, page 12 / 129 7 / 51 is paper-based and comprises a silicone-coated adhesive contact side.

[0040] In some forms, the adhesive seal is elongated and stretchable.

[0041] Optionally, the seal is not curable.

[0042] In a fourth aspect, the invention largely consists of a wound treatment system comprising a wound dressing, as described above in relation to the first aspect, and the moldable adhesive seal described above in relation to the second aspect, wherein the moldable adhesive seal is applied around the perimeter of a patient's skin wound.

[0043] In one embodiment, the occlusive layer is adhered over the moldable adhesive seal.

[0044] In one embodiment, a negative pressure source is coupled to the conduit to apply negative pressure to the wound.

[0045] In one embodiment, the system comprises a reservoir for collecting exudate removed from the dressing.

[0046] The present invention may also consist broadly of parts, elements and features referred to or indicated in the Patent Application Description, individually or collectively, and in any or all combinations of any two or more of said parts, elements or features. Where specific whole numbers are mentioned herein which have known equivalents in the prior art to which the present invention relates, such known equivalents are considered incorporated herein as if they had been described individually.

[0047] The term "comprising," as used in this Descriptive Report and the claims, means that it consists of at least part of. In interpreting the statements made in this Report Petition 870260051284, dated 05 / 28 / 2026, p. 13 / 129 8 / 51 Descriptive and in claims that include the term "comprising," other features besides those preceded by this term may also be present. Related terms, such as "comprising" and "comprising," should be interpreted in a similar manner.

[0048] It is desired that the reference to a range of numbers described in this document (for example, 1 to 10) also incorporates the reference to all rational numbers within that range and any range of rational numbers within that range (for example, from 1 to 6, from 1.5 to 5.5 and from 3.1 to 10). Therefore, all subranges of all ranges expressly described in this document are hereby expressly described.

[0049] As used in this document, the term(s) following a noun means the plural and / or singular form of that noun. As used in this document, the term and / or means and or or or, where the context permits, both. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The present invention will now be described only by way of example and with reference to the accompanying drawings.

[0051] Figure 1 is a perspective view of a negative pressure wound dressing of the prior technique.

[0052] Figure 2 is a perspective view of a negative pressure wound dressing of the prior additional technique.

[0053] Figure 3 is a close-up perspective view of an early embodiment of the negative pressure wound dressing described in this document.

[0054] Figure 4 is an exploded perspective view of the wound dressing in Figure 3.

[0055] Figure 5 is a close-up perspective view of a second type of negative pressure wound dressing. Petition 870260051284, dated 05 / 28 / 2026, page 14 / 129 9 / 51

[0056] Figures 6(i) and 6(ii) are perspective views of the carrier layer of Figure 5, wherein Figure 6(i) shows the top surface of the layer and Figure 6(ii) shows the bottom side.

[0057] Figures 7(i) to 7(iii) are detailed views showing the highlighted portion of the carrier layer of Figure 5, wherein Figure 7(i) is an isometric view showing the top surface of the layer, Figure 7(ii) is an aerial perspective view and Figure 7(iii) is a perspective view of the underside.

[0058] Figures 8(i) and 8(ii) are perspective views of an alternative embodiment of the carrier layer which has undulating ribs, wherein Figure 8(i) shows the upper surface of the layer and Figure 8(ii) shows the lower side.

[0059] Figures 9(i) to 9(iii) are detailed views showing a highlighted portion of the carrier layer of Figures 8(i) and 8(ii), wherein Figure 9(i) is an isometric view showing the top surface of the layer, Figure 9(ii) is an aerial perspective view and Figure 9(iii) is a perspective view of the underside.

[0060] Figures 10(i) and 10(ii) are perspective views of an alternative embodiment of the carrier layer having square ribs, wherein Figure 10(i) shows the top surface of the layer and Figure 8(ii) shows the bottom side.

[0061] Figures 11(i) to 11(iii) are detailed views showing a highlighted portion of the carrier layer of Figures 10(i) and 10(ii), wherein Figure 11(i) is an isometric view showing the top surface of the layer, Figure 11(ii) is an aerial perspective view and Figure 11(iii) is a perspective view of the underside.

[0062] Figures 12(i) to 12(iv) constitute a series of schematic diagrams showing the block-building process of regenerative tissue that forms in the carrier layer passages and the non-traumatic removal after proper treatment. Petition 870260051284, dated 05 / 28 / 2026, p. 15 / 129 10 / 51 successful.

[0063] Figure 13 is a close-up perspective view showing a portion of a bioabsorbable layer with multi-layered ears exemplifying according to a modality.

[0064] Figures 14(i) and 14(ii) are partial section views of exemplary multi-sheet bioabsorbable layers, wherein Figure 14(i) shows an embodiment that has lugs formed from the top sheet that couple with the underlying sheets, and Figure 14(ii) shows an embodiment that also has a sheet with a bottom lug coupled with the overlying sheets.

[0065] Figures 15(i) and 15(ii) illustrate an embodiment of the bioabsorbable layer that has X-shaped openings, wherein Figure 15(i) shows the flattened layer and Figure 15(ii) shows the edges of the openings that deform to allow more flow through the openings.

[0066] Figures 16(i) to 16(iii) also illustrate the operation of the bioabsorbable layer openings of Figures 15(i) and 15(ii), wherein Figure 16(i) is a plan view of an opening in a flattened sheet, Figure 16(ii) illustrates the opening deforming when the sheet is placed on a contoured wound surface and Figure 16(iii) shows the edges of the openings deformed to allow more flow through the opening.

[0067] Figures 17(i) to 17(iii) illustrate the fluid flow passages through the bioabsorbable layer of Figures 16(i) to 16(iii), wherein Figure 17(i) is a close-up perspective view illustrating the sheet placed on a contoured wound surface; Figure 17(ii) is a schematic side view showing the edges of the openings deformed to allow more flow through the opening and Figure 17(iii) illustrates the fluid flow passages through the openings.

[0068] Figure 18 illustrates a graft of the previous technique with Petition 870260051284, dated 05 / 28 / 2026, p. 16 / 129 11 / 51 alternating linear expansion fenestrations, wherein Figure 18(i) is a highlighted perspective view illustrating the graft placed on a contoured wound surface; Figure 18(ii) illustrates the deformation of the fenestrations to accommodate the undulations of the wound surface; and Figure 18(iii) illustrates the restricted flow through the graft.

[0069] Figures 19(i) to 19(iv) are perspective views illustrating four bioabsorbable layers of the exemplary alternative modality, wherein Figure 19(i) shows a modality that has oval openings, Figure 19(ii) shows a modality that has X-shaped slits, Figure 19(iii) shows a modality that has Y-shaped slits and Figure 19(iv) shows a modality that has C-shaped slits.

[0070] Figures 20(i) and 20(ii) are plan views illustrating two bioabsorbable layers of the exemplary alternative embodiment, wherein Figure 20(i) shows an embodiment having circular openings and Figure 20(ii) shows an embodiment having C-shaped notches.

[0071] Figures 21(i) and 21(ii) illustrate the operation of the bioabsorbable layer openings of Figure 19(iv), wherein Figure 21(i) is a perspective view showing the deformation of the bioabsorbable layer to conform to a contoured wound surface and Figure 21(ii) shows the fins defined by the slits, deformed to allow more flow through the openings.

[0072] Figures 22(i) and 22(ii) illustrate the operation of the bioabsorbable layer openings of Figure 19(iii), wherein Figure 22(i) is a perspective view showing the deformation of the bioabsorbable layer to conform to a contoured wound surface and Figure 22(ii) shows the fins defined by the slits, deformed to allow more flow through the openings.

[0073] Figures 23(i) and 23(ii) illustrate the operation of the openings Petition 870260051284, dated 05 / 28 / 2026, page 17 / 129 12 / 51 of the bioabsorbable layer of Figure 19(i), wherein Figure 23(i) is a perspective view showing the deformation of the bioabsorbable layer to conform to a contoured wound surface and Figure 23(ii) shows the flow through the openings.

[0074] Figures 24(i) to 24(iii) illustrate an alternative form of the bioabsorbable layer formed of a reticulum, wherein Figure 24(i) is a perspective view showing the textured top surface of a reticulum sheet, Figure 24(ii) is a perspective view of the top of the layer, with X-shaped notches, and Figure 24(iii) is a perspective view of the underside of the layer.

[0075] Figure 25 is an illustrative perspective view showing the wound dressing described in this document on a foot wound.

[0076] Figure 26 is a view corresponding to Figure 25, showing the process of removing the moldable strip from the foot dressing.

[0077] Figure 27 is an illustrative perspective view showing the placement of the wound dressing described in this document on an arm wound.

[0078] Figure 28 is a view corresponding to Figure 27, showing the process of removing the moldable dressing strip from the arm.

[0079] Figure 29 is a schematic cross-sectional diagram showing moldable rubber adhered to the skin.

[0080] Figure 30 is a view that corresponds to Figure 29, showing the removal of the moldable rubber.

[0081] Figure 31 is a close-up perspective view of the negative pressure wound dressing according to a third embodiment, which has a pressure distribution layer.

[0082] Figure 32 is an exploded perspective view of the wound dressing in Figure 31.

[0083] Figure 33 is a close-up perspective view of Petition 870260051284, dated 05 / 28 / 2026, p. 18 / 129 13 / 51 Negative pressure wound dressing according to a fourth modality, which has an alternative modality of the pressure distribution layer.

[0084] Figure 34 is a cross-sectional view of an embodiment of the double lumen conduit, comprising a primary conduit for applying negative pressure to the dressing and a secondary conduit for instilling fluid into the dressing or for measuring pressure.

[0085] Figures 35(i) and 35(ii) are illustrative views of a sleeve embodiment, where Figure 35(i) refers to a view along the axis of the component's through hole and Figure 35(ii) refers to an isometric view of the sleeve.

[0086] Figures 36(i) and 36(ii) are illustrative views of the embodiment of the double lumen conduit of Figure 34 mounted on the elastomeric sleeve component of Figure 35(i) and 35(ii), with the double lumen conduit being cut along the second end of the conduit to expose the primary and secondary conduits of the double lumen conduit along a length.

[0087] Figure 37 is a close-up perspective view of a negative pressure wound dressing according to a fifth embodiment, incorporating the assembled double lumen conduit and elastomeric sleeve component of Figures 36(i) and 36(ii).

[0088] Figure 38 is an exploded perspective view of the wound dressing in Figure 37.

[0089] Figure 39 is an exploded perspective view of an apparatus used to prepare a bioabsorbable layer of the invention.

[0090] Figure 40 is an exploded perspective view of the tooling used within the apparatus described in Figure 39.

[0091] Figures 41(i) and 41(ii) are cross-sectional views illustrating the operating process of the apparatus in Figure 39 for preparing Petition 870260051284, dated 05 / 28 / 2026, page 19 / 129 14 / 51 a bioabsorbable layer of the invention.

[0092] Figure 42 is an exploded perspective view of the pressure drop measuring apparatus described in this document.

[0093] Figure 43 is a graph that displays the results of measuring the pressure drop across various wound contact devices in response to two different levels of applied negative pressure. DETAILED DESCRIPTION I. Definitions

[0094] The term extracellular matrix (ECM), as used herein, refers to an animal or human tissue that has been decellularized and provides a matrix for structural integrity and a framework to contain other materials.

[0095] The term decellularized, as used herein, refers to the removal of cells and their related debris from a portion of a tissue or organ, for example, from the ECM.

[0096] The term polymeric material, as used herein, refers to large molecules or macromolecules comprising many repeating subunits, and may be natural materials, including but not limited to polypeptides and proteins (e.g., collagen), polysaccharides (e.g., alginate) and other biopolymers such as glycoproteins, or may be synthetic materials, including but not limited to polypropylene, polytetrafluoroethylene, polyglycolic acid, polylactic acid and polyester.

[0097] The term interlock or lock, as used herein, refers to the mechanical coupling of two or more overlapping sheets of material.

[0098] The term sheet, as used herein, refers to a substantially flat flexible section of ECM or polymeric material.

[0099] The term ear, as used here, refers to the section Petition 870260051284, dated 05 / 28 / 2026, p. 20 / 129 15 / 51 of a sheet that has been partially cut, so that the ear remains firmly attached to the sheet by means of a connecting bridge.

[00100] In this Descriptive Report and in the Claims, the terms negative pressure and vacuum pressure may be used interchangeably to mean a standard pressure lower than ambient pressure and an absolute pressure lower than atmospheric pressure. Alternative terms include subatmospheric pressure, suction pressure, or reduced pressure. For example, a negative pressure or vacuum pressure of 100 mm Hg is a standard pressure of -100 mm Hg or an absolute pressure of about 660 mm Hg. The terms higher or increased, when used in relation to negative or vacuum pressure, lend themselves to indicating a higher or increased negative pressure. For example, a standard pressure of -150 mm Hg (610 mm Hg absolute) is higher than a standard pressure of -100 mm Hg (660 mm Hg absolute).Similarly, with regard to the terms lower, decreased, when used in relation to a negative pressure or vacuum, they lend themselves to indicating a lower or decreased negative pressure. For example, a standard pressure of -100 mm Hg is lower than a standard pressure of -150 mm Hg.

[00101] In this Descriptive Report and Claims, unless the context indicates otherwise, the term exudate is used to mean any fluid removed from a patient's wound site. For example, exudate may include fluid produced by the patient and / or fluid applied to the wound site by a system, including air or a treatment fluid, such as saline solution or a fluid-providing medication, or fluid from a surgical procedure that may have introduced or administered treatment fluids to the wound site via a separate route, such as by injection. II. Device Petition 870260051284, dated 05 / 28 / 2026, p. 21 / 129 16 / 51

[00102] Several embodiments will now be described with reference to Figures 1 to 40. In these figures, the same reference numbers will be used in different embodiments to indicate similar features, with the addition of a multiple of 100. Directional terminology, such as the terms anterior, posterior, superior, inferior and other related terms, is used in the following description only for ease of description and reference, and is not intended to be limiting.

[00103] In general, the invention discloses a multi-layered wound dressing system comprising a wound dressing comprising at least one layer of bioabsorbable material and at least one other layer of material comprising openings that act as fluid ports to allow fluid to pass through the layers and the wound site. The fluid may be a gas or a liquid or both. The multi-layered wound dressing also comprises an adhesive portion, such as a moldable seal, that surrounds the wound site in order to define the boundary of a wound treatment region. Typically, the adhesive portion is provided on intact skin, outside the wound boundary. The adhesive portion is also sealed to a liquid-impermeable occlusive layer to provide a closed environment around the wound and to define the wound treatment region.The multi-layer wound dressing system also includes a negative pressure component comprising at least one conduit with a distal end terminating within the closed environment created by the wound dressing, allowing treatment fluid to be applied to the wound site and exudate to be removed from the wound site. The conduit also allows negative pressure to be applied to the closed environment surrounding the wound. Negative pressure aids in wound healing and therefore can reduce the wound healing time.

[00104] Figures 3 and 4 illustrate a first wound dressing of Petition 870260051284, dated 05 / 28 / 2026, p. 22 / 129 17 / 51 exemplary embodiment 101 suitable for applying negative pressure to a wound 103. The dressing 101 comprises a bioabsorbable layer 105 to be placed in contact with a wound surface 103, an occlusive outer layer impermeable to liquids 107, a carrier layer 109 between the outer layer 107 and the bioabsorbable layer 105, and a fluid conduit 111 in fluid communication with the carrier layer 109, for coupling to a source of negative pressure. Bioabsorbable layer

[00105] With reference to Figures 13 and 14, the bioabsorbable wound contact layer 105 comprises a flexible multi-layered structure. In the exemplary embodiments of this document, the bioabsorbable layer 105 comprises a plurality of overlapping layers 113a, 113b that are mechanically interlocked with each other, for example, by using portions of one or more of the layers to couple with one or more of the other layers. The mechanical interlocking of the layers 113a, 113b fixes the layers together without the need for the addition of other materials, such as adhesives or sutures, or without the need for treatments such as compression and dehydration. Furthermore, these multi-layered structures exhibit greater combined tensile strength than individual layers.

[00106] The multi-layered structure of the bioabsorbable layer 105 can be produced according to the method described in Patent Application PCT / NZ2015 / 050215, which is incorporated herein by reference. Blocked multi-sheet bioabsorbable layers exemplifying 105, 105' produced according to this method are illustrated in Figures 13, 14(i), and 14(ii)). In the embodiments shown, the bioabsorbable layer 105 comprises a first sheet with a lug 113a, 113a having a plurality of lugs 115 formed by cutting a U-shaped or C-shaped slit in the. Petition 870260051284, dated 05 / 28 / 2026, p. 23 / 129 18 / 51 first sheet to create an ear-like flap. The underlying or overlying sheets 113b have a plurality of perforations 117 and each ear 115 is pushed through the respective underlying or overlying perforations 117 in order to lock the sheets together to create a laminate with ears. The resulting structure contains recesses 114 in the ear sheet where each ear 115 has been cut from the sheet. Each ear 115 remains attached to its respective ear sheet 113, through a connecting bridge 116, thus locking the sheets together to hold them in place.

[00107] In the exemplary embodiments 105, 105' shown in Figures 14(i) and (ii), there are three or four perforated sheets, but alternatively, the bioabsorbable layer may comprise more or fewer perforated sheets. The number of overlapping sheets fixed at different points of the bioabsorbable layer may vary, for example, if different properties are required in different areas of the bioabsorbable layer.

[00108] In some embodiments, the bioabsorbable layer may comprise more than one 113a ear sheet, for example, having upper and lower ear sheets, as illustrated in Figure 14(ii). In this embodiment, three perforated sheets 113b' are sandwiched between an upper ear sheet and a lower ear sheet 113a. The ears 115' of the upper ear sheet have been pushed through the perforations 117' of the middle sheets 113b' to the underside of the lower ear sheet, and the ears 115' of the lower ear sheet have been pushed through the perforations of the middle sheets 113b' to the upper surface of the upper ear sheet.

[00109] The ears of the lower-eared leaf can be aligned with the ears on the upper leaf, as shown in the embodiment of Figure 14(ii), or they can be offset to prevent ears on different-eared leaves from being pushed through the Petition 870260051284, dated 05 / 28 / 2026, p. 24 / 129 19 / 51 same perforations 117'. The mechanical properties of the product can also be adapted to the application requirements by modifying the shape of the ears or by using a different pattern, size, density and / or shape of the ears.

[00110] Ears 115, 115' may or may not be pushed through all underlying or overlying leaves and, for embodiments with more than one ear leaf, they may or may not be pushed through another ear leaf.

[00111] The 117, 117' ear perforations in the bioabsorbable layer with multi-sheet ears provide a plurality of microchannels through the sheet. Advantageously, these channels aid in the flow of wound fluid through the bioabsorbable layer and assist in applying pressure to the wound due to the channels provided by the ear perforations.

[00112] The sheets of the bioabsorbable layer 113 comprise the extracellular matrix (ECM) or a polymeric material. ECM-derived matrices for use in embodiments of the present invention are biodegradable collagen-based matrices comprising collagens, glycoproteins, proteoglycans, and glycosaminoglycans highly conserved in their natural configuration and concentration. An extracellular collagen matrix for use in the present invention is the ECM of a warm-blooded vertebrate. ECM can be obtained from various sources, for example, gastrointestinal tissue harvested from animals raised for meat production, including pigs, cattle, and sheep or other warm-blooded vertebrates. Vertebrate ECM is an abundant byproduct of commercial meat production operations and is thus a low-cost tissue graft material. An exemplary method of preparing ECM is described in U.S. Patent No. 8,415,159.

[00113] In some embodiments of the invention, the resorbable polymeric material can be included in the bioabsorbable layer as sheets of Petition 870260051284, dated 05 / 28 / 2026, page 25 / 129 20 / 51 ears, perforated sheets and / or otherwise three-dimensional shape. For example, meshes comprising synthetic materials such as polyglycolic acid, polylactic acid and polyglecaprone-25 will provide additional short-term strength but will resorb in the long term. Alternatively, the polymeric material may be a natural material or derived from natural material, such as proteins (e.g. collagen), polysaccharides (e.g. alginate), glycoproteins or other materials.

[00114] In some embodiments, the bioabsorbable layer 105 may comprise one or more reticulum sheets 1113 (see Figure 24), which may be produced according to the method described in Patent Application PCT / NZ2009 / 000152, which is incorporated herein by reference. The reticulum is a propriosacral submucosa of the forestomach of a ruminant that possesses a unique raised honeycomb appearance on the luminal surface of the tissue. These honeycomb features are created by a series of continuous native projections comprised of predominantly dense collagen that create a wavy surface of varying texture on the luminal face of the reticulum tissue. The abluminal surface generally presents a smooth appearance following delamination and removal of the muscle layer. When these raised projections retain an element of elasticity, they are relatively incompressible when subjected to negative pressure applied within wound therapy.

[00115] The raised ridges of the reticulum also aid in pressure distribution across the surface of each individual honeycomb pouch, preventing collapse and sealing of adjacent dressing materials, which is a unique characteristic of native material. The bioabsorbable layer 105 can also be treated for the application of bioactive materials to the wound site. The bioactive materials can be endogenous to the ECM used in the preparation of a graft product or Petition 870260051284, dated 05 / 28 / 2026, page 26 / 129 21 / 51 They can be materials that are incorporated into the ECM and / or polymeric material layers during or after fabrication. Bioactive materials applied to the wound site in this manner are known to be beneficial in promoting cellular function, including wound healing and other desirable physiological and pharmacological functions.

[00116] In other embodiments, the bioabsorbable layer 105 may comprise one or more sheets of ECM derived from the rumen, which is another proper submucosa of the forestomach of a ruminant, and is also described within Patent Application PCT / NZ2009 / 000152.

[00117] With reference to Figures 13, 14 and 24 (i) to 24 (iii), the use of forestomach tissue in the construction of a multi-layered bioabsorbable layer with ears 105 presents other additional benefits. As described within Patent Application PCT / NZ2009 / 000152, tissue support structures originating from forestomach tissue typically exhibit a contoured surface of varying appearance according to the particular origin of the support structure (such as the rumen, reticulum or omasum), where the abluminal surface generally has a smooth appearance following delamination and removal of the muscle layer. In particular reference to the rumen, the luminal surface of this tissue support structure exhibits several surface protrusions known as papillae, which visually resemble hair-like elements projecting from the luminal surface.When a bioabsorbable layer 105 is constructed according to the aforementioned ear-laminated process using rumen tissue, the resulting ear-laminated layer comprises an interstitial space formed between adjacent layers of laminate due to the papillae located within each interstitial space, which prevents the adjacent layers from forming a tight seal. This interstitial space is not limited to laminates using rumen tissue. Others. Petition 870260051284, dated 05 / 28 / 2026, page 27 / 129 22 / 51 modalities comprising resorbable foam and other resorbable polymeric materials may also comprise an interstitial space between adjacent sheet layers.

[00118] The multi-layered bioabsorbable layer 105 comprises a plurality of main openings, which may include slits (formed from cuts made without removing material from the layer), notches (with spaced lateral edges as a consequence of material removed from the layer) or any other appropriate form of opening, such as a regularly or irregularly shaped opening, through the bioabsorbable layer 105, to define a multiplicity of passages for fluids. These passages allow flow from the wound to the carrier layer 109.

[00119] In the embodiment shown in Figures 15(i) to 17(iii), the openings in the bioabsorbable layer 105 comprise a set of X-shaped openings formed by two intersecting notches 119. The bioabsorbable layer is flexible, so that each X-shaped opening can define four generally triangular flaps 121 in the bioabsorbable layer. The two free edges of each triangular flap 121 are formed by a pair of notches extending through the same generally central point in an arrangement perpendicular to each other to form a cross, with the third edge of the triangular flap forming a joint with the body of the bioabsorbable layer.

[00120] These X-shaped notches allow the bioabsorbable layer 105 to flex in order to conform to the undulations on the wound surface 103, as illustrated in Figure 17(i), where the edges of a given notch can move closer together to accommodate a concavity, or can spread out to accommodate a convex surface. Therefore, the bioabsorbable layer can be in substantial full contact with the wound surface. The X-shaped openings also have other benefits, Petition 870260051284, dated 05 / 28 / 2026, p. 28 / 129 23 / 51 allowing the passage of wound exudate fluid through the layer and also allowing negative pressure therapy applied to the wound surface 103 over a large equivalent area without removing a large area of ​​material, thus reducing the amount of bioactive material that is applied to the wound by the bioabsorbable layer 105.

[00121] In another embodiment shown in Figure 16(i), the X shape formed by the intersecting notches 119 has a width and a height of about 5.5 mm. Preferably, the notch has a width of about 0.5 mm, with about 5 mm2 of the resulting bioabsorbable material removed from the layer 105. On the other hand, if the openings formed in the bioabsorbable layer are in the form of a circular perforation similar to that of Figure 20(i) with a diameter of about 5.5 mm, then about 24 mm2 of the bioabsorbable material must be removed in order to provide an opening of this size and a comparable level of negative pressure provided to the wound surface and fluid exchange capacity through the bioabsorbable layer 105, as experienced when using the cross-shaped openings of Figure 16(i).

[00122] In other embodiments, the width and height of the X-shaped opening may be longer in one direction than in another or may comprise several notches of different sizes through the bioabsorbable layer 105. The length of the notches forming the X shape may vary from about 3 mm to about 15 mm in width and length, with the width of each notch varying from about 0.2 mm to about 2 mm wide.

[00123] In some forms, openings are provided in the bioabsorbable layer in a generally regular arrangement, such as being situated in substantially aligned columns and rows. In other forms, the openings may be arranged in an offset or alternating arrangement. In still other forms, the openings may be provided in a Petition 870260051284, dated 05 / 28 / 2026, page 29 / 129 24 / 51 irregular arrangement or in a random arrangement in the bioabsorbable layer.

[00124] Figures 18(i) to 18(iii) show a known graft product that includes linear fenestrations / slits 419 instead of openings formed as a result of material being removed from the product. If used in a dressing, these fenestrations / slits are less likely to assume undulations in the longitudinal and transverse directions. Linear slits only provide a narrow opening for fluid 420 to flow through the graft, as they are formed without removing material from the graft product. Consequently, linear slits can only allow fluid removal from a smaller region of the wound site than the openings of the present invention.Furthermore, the linear fenestrations 419 close easily once the graft 405 is in situ due to the moisture absorbed by the graft 405, causing swelling of the graft near the slits 419, which also closes the narrow openings. Regenerating tissue, wound fluids such as blood, red blood cells, fibrin, and other wound phenomena such as scabs and residual healing tissue are also collected and remain in these narrow fenestrations and can cause the fenestrations to become blocked. Additionally, lateral movement of the graft within the wound can cause the linear slit fenestrations to close with the slightest movement, preventing any fluid exchange through the layer.

[00125] On the other hand, as illustrated in Figures 15(ii), 16(iii), 17(ii) and 17(iii), the tabs 121 defined by the X-shaped openings / notches of the dressing of the present invention can move upwards in order to increase the size of the opening and thus increase the size of the fluid passages 120 provided by the notches 119. This can happen under pressure, for example, due to the negative pressure being applied to the dressing, and allows the fluid passages to be maintained even if there is some swelling. Petition 870260051284, dated 05 / 28 / 2026, page 30 / 129 25 / 51 of the material surrounding the notches. In order to facilitate fluid removal from the wound site, maintaining fluid passages allows for more efficient application of negative pressure to the wound site because larger openings in the bioabsorbable layer are advantageously associated with less pressure drop across the bioabsorbable layer thickness 105. Furthermore, X-shaped notches are also less prone to closure when the graft moves within the wound as the X-shaped openings tilt in response to lateral movement in order to maintain the openings through the bioabsorbable layer.

[00126] In alternative embodiments, the main openings of the bioabsorbable layer 119 may have alternative shapes. For example, instead of being X-shaped, the openings may be notches of another two-dimensional shape, such that each of them defines one or more flaps that can move to accommodate the contours and can move to increase the size of the passage for fluids through the opening. For example, appropriate notch shapes include notches that have a curved portion or that comprise two or more linear portions arranged at an angle to form an arrowhead-type arrangement. Each flap is created by two or more adjacent linear notch edges or by a convex / curved notch, with the notch edge or edges defining the free (movable) edges of the flap and a virtual line between the two distal ends of the curved notch or pair of notches forming the flap joint.In some forms, instead of presenting an X shape, in alternative embodiments, the notches 119 may have a Y shape, C shape, U shape, or V shape. Each Y-shaped notch defines three tabs, and each C-shaped, U-shaped, or V-shaped notch defines one tab.

[00127] Each notch or other main opening is formed by Petition 870260051284, dated 05 / 28 / 2026, p. 31 / 129 26 / 51 removal of material from the bioabsorbable layer. For example, by means of slicing, by making spaced cuts and removing the intermediate material, or by means of die cutting or laser cutting, whereby the material is removed by a single pass of the laser beam, and the width of the notch corresponds to the width of the laser beam.

[00128] Alternatively, instead of a notch where material has been removed from the bioabsorbable layer, tabs for fluid passages can be formed using formed slits, created by cut lines where no material is removed from the sheet. The slits can be linear or curved, as described above in relation to notches, have a two-dimensional shape, or the slits can be formed by a non-linear cut or cuts of interesting / irregular shapes, so that each slit defines one or more tabs that are movable to accommodate the contours of the wound site. The tabs are movable to open in order to create a passage for fluids or increase the size of the passage for fluids through the layer in the slit. Figures 19(ii) to 19(iv) illustrate some exemplary slit arrangements.Figure 19(ii) illustrates an embodiment 605 having X-shaped slots 619, with each slot 619 defining four flaps that are movable in the manner described above with respect to the X-shaped notches. Figures 19(iii), 22(i) and 22(ii) illustrate an embodiment 705 with Y-shaped slots 719, each being formed of three intersecting linear cuts to define three flaps 721. Figures 19(iv), 21(i) and 21(ii) illustrate an embodiment 805 with variably oriented C-shaped slots 819, with each slot 819 defining a single flap 821.

[00129] As an additional alternative, the main openings in the bioabsorbable layer may comprise a plurality of openings that do not form flaps, for example, around openings 919, such as Petition 870260051284, dated 05 / 28 / 2026, page 32 / 129 27 / 51 as shown in Figure 20(i), oval or oblong openings 519, as shown in Figures 19(i), 23(i) and 23(ii), or openings of other shapes. In these embodiments, the bioabsorbable layers do not comprise movable flaps to increase the size of the passage for fluids through the layer. Instead, the openings provide a larger opening than the notches described above for efficient pressure transfer to the wound and passage for fluids. However, this increase in opening size is associated with a reduction in the area of ​​the bioabsorbable layer 505, 905 that is in contact with the wound surface, thus reducing the therapy area. Sheets that have larger openings may also be more difficult to manipulate.

[00130] In some embodiments, to provide a multilayer dressing with openings 119 within the bioabsorbable layer 105 that do not interfere with the blocking ears, the openings may be arranged in a grid pattern and the ears 115 may be arranged in at least some of the adjacent openings in a layer. The width of the openings 119 may also be longer on one axis than on another in order to provide sufficient space in the layer for the blocking ears 115, so that the width of each main opening 119 may span the equivalent length of two or more adjacent ears 115, but be limited in height. In other embodiments, the openings 119 within the bioabsorbable layer 105 may be arranged in an alternating pattern. carrier layer

[00131] The carrier layer 109 is positioned on top of the bioabsorbable layer 105, between the bioabsorbable layer and the occlusive layer 107. The carrier layer 109 defines a multiplicity of passages for fluids between the conduit 111 and the bioabsorbable layer 105, to allow the conduction of the bioabsorbable layer and the passage of the Petition 870260051284, dated 05 / 28 / 2026, p. 33 / 129 28 / 51 wound exudate outside the bioabsorbable layer 105.

[00132] The carrier layer 109 maintains the spacing between the bioabsorbable layer 105 and the outer occlusive layer 107 under the application of negative pressure to the dressing through the conduit 111. This carrier layer 109 also provides some protection to the wound 103 by cushioning the wound, and helps to distribute the negative pressure from the conduit 111 to the bioabsorbable layer over a wide area, and not to the area immediately adjacent to the conduit.

[00133] The carrier layer 109 comprises a material selected to minimize pressure drop across the layer 109 while also discouraging internal tissue growth. The carrier layer 109 must also confer sufficient structural integrity to allow fluid passage through the carrier layer under high pressure levels, such as between about 125 mm Hg and about 250 mm Hg vacuum pressure. In one embodiment, the carrier layer comprises a compliant porous material such as a solid-state water-permeable synthetic foam. The foam is at least of a semi-open cell nature to allow fluid passage through the foam layer. The greater the porosity of the foam layer and the stiffer the material, the lower the pressure drop.

[00134] In one embodiment, the carrier layer 109 comprises a microbicidal open-cell foam or a semi-open / semi-closed cell foam such as a PVA foam. The foam is flexible and compressible to conform to and cushion the wound site 103. Some openness is required in the sublayer 123 to allow pressure conduction and fluid transfer through the layer. However, more open foams such as cross-linked polyurethane are generally more susceptible to ingrown tissue, which is undesirable. The use of a semi-closed foam such as a Petition 870260051284, dated 05 / 28 / 2026, p. 34 / 129 29 / 51 PVA foam immediately adjacent to the bioabsorbable layer reduces the possibility of inward tissue growth in the foam layer. Furthermore, the carrier layer 109 may also comprise a series of channels 125 to further improve pressure conduction and fluid transfer through the carrier layer 109.

[00135] With reference to the embodiment shown in Figure 37 and Figure 38, the carrier layer 1409 comprises a non-crosslinked hydrophilic polyurethane foam comprising an absorbent polymer, such as sodium polyacrylates, within the foam sublayer 1423 to impart a hydrophilic property. The non-crosslinked hydrophilic polyurethane foam is a medium-density foam with a pore size of about 200 µm to about 400 µm. In other embodiments, the foam contains a pore size distribution ranging from about 10 µm to about 600 µm. In some embodiments, the foam may be a dense foam with a pore size of about 20 µm to about 50 µm, and may contain a pore size distribution ranging from about 5 µm to about 150 µm.

[00136] The surface of the carrier layer 1409 may comprise a silicone layer that forms an interface with the bioabsorbable layer 1405. In the embodiment of Figures 37 and 38, the carrier layer 1409 comprises an alternating pattern of x-shaped channels 1425 that are comparable to the shape illustrated in Figure 16(i). The channels 1425 are approximately 12 mm high and approximately 12 mm wide with a notch width of approximately 2 mm when applied to the wound site. The height and width of the channels 1425 may vary from approximately 3 mm to approximately 15 mm and may also vary in width from 0.5 mm to 8 mm. The channels 1425 are spaced in the alternating pattern with repeating channels 1425 spaced approximately 20 mm apart from each other along a first axis and spaced approximately 10 mm apart from each other Petition 870260051284, dated 05 / 28 / 2026, p. 35 / 129 30 / 51 mm on a second axis that is perpendicular to the first axis. The carrier layer 1409 is about 8 mm thick, but can still be about 3 mm thick to about 30 mm thick depending on the wound geometry 103, such as depth, and site comfort requirements, such as areas around the base of the spine and buttocks.

[00137] In another embodiment, the carrier layer 1409 may comprise a medium-density PVA foam with a pore size distribution ranging from about 10 µm to about 600 µm. The foam may also be a dense foam with a pore size distribution of about 20 µm to about 30 µm. The PVA foam may also retain a microbicidal agent. The carrier layer 1409 may also contain a series of x-shaped channels 1425 arranged in an alternating pattern. The channels 1425 are about 6 mm high and about 6 mm wide with a notch width of about 1.5 mm when measured in an unhydrated or dry form. The height and width of the channels 1425 may vary from about 3 mm to about 15 mm and may also vary from about 0.5 mm to about 8 mm in width.The 1425 channels are spaced in an alternating pattern with repetition of the 1425 channels spaced approximately 14 mm apart along a first axis of approximately 7 mm along a second axis that is perpendicular to the first axis. The carrier layer 1409 is approximately 5 mm thick when measured in a dry form, but may also be approximately 2 mm to 20 mm thick depending on the wound geometry 103, or may be confined for the treatment of areas such as deep tunnel wounds or areas where undermining occurs.

[00138] The carrier layer 109 has liquid transfer properties from the bioabsorbable layer. PVA foams, unlike cross-linked foams, are denser, since they contain Petition 870260051284, dated 05 / 28 / 2026, p. 36 / 129 31 / 51 A greater amount of PVA material in the cell walls of the foam pores allows high levels of moisture to be absorbed and retained within the foam. When used for the carrier layer 109, PVA provides a fluid absorbance gradient that draws excess moisture from the bioabsorbable layer to allow cells important for wound healing to migrate to the bioabsorbable layer and proliferate. PVA foams that are combined with microbicidal agents also further reduce the risks of infection associated with retained wound fluid settling in a wound while also being able to elute the microbicidal agent to control high levels of bioburden and unwanted microbial activity. Examples of such microbicides may include silver, tetracyclines, gentian violet, methylene blue, and chlorhexidine.

[00139] In addition to the multiple fluid passages inherent in the foam, provided by the foam's porosity, the carrier layer 109 may comprise an arrangement of through channels 125 that are substantially perpendicular to the interface between the carrier layer 109 and the bioabsorbable layer 105 and extend through the entire thickness of the carrier layer 109. These channels 125 reduce the pressure drop across the carrier layer 109 to ensure that negative pressure is effectively applied to the bioabsorbable layer 105.

[00140] The through channels 125 are preferably linear and x-shaped, as shown in Figure 37, but, on the other hand, they can be of any suitable cross-section and configuration, such as round or oval, as shown in the alternative embodiment of Figure 5. The cross-section through the channels is preferably many times larger than that of the fluid passages inherent in the foam.

[00141] The 124 through channels, together with the semi-enclosed nature Petition 870260051284, dated 05 / 28 / 2026, page 37 / 129 32 / 51 of the foam, ensure that a low pressure drop is provided across the carrier layer 109 to allow effective application of negative pressure, while reducing inward tissue growth. Figure 12 illustrates the process of inward tissue growth in a through channel 124 of the carrier layer as the wound heals. However, due to the fact that inward tissue growth in the foam itself is minimal, the carrier layer can be lifted from the wound without also removing significant amounts of tissue, as shown in Figure 12(iv).

[00142] In the embodiment of Figure 3, an upper surface of the carrier layer 109 is undulating with peaks 127 and valleys 128. The occlusive layer 107 is stretched across the carrier layer 109, settling on the peaks 27 in such a way that in the valleys 28 a gap is formed between the occlusive layer and the adjacent upper surface of the carrier layer 109. With respect to Figure 7 (i), these gaps form fluid passages 124 to assist in applying negative pressure across the entire width of the carrier layer 109, and also to assist in the passage of fluids from the carrier layer 109 to the conduit 111.

[00143] With respect to Figures 6(i) to 7(iii), in the embodiment of Figure 3, the upper surface of the carrier layer 109 is undulating in two directions wherein an arrangement of peaks 127 defines an interlacing of diagonally crossed flow passages 124. The openings of the through channels 124 are situated in the valleys 128 between the peaks 127 in such a way that they are in fluid communication with the fluid flow passages that pass between the peaks 127.

[00144] In alternative embodiments, the upper surface of the carrier layer 109 may comprise a series of ribs 327. The ribs 327 may be curved as shown in Figures 8(i) to 9(iii), or they may be stepped, as shown in the example of Petition 870260051284, dated 05 / 28 / 2026, p. 38 / 129 33 / 51 Figures 10(i) to 11(iii). In the embodiment of Figure 10(i), the openings of the fluid channels 324 pass through the peaks of the ribs 327. This allows free flow of fluids along the adjacent valleys 328, thus ensuring that the applied negative pressure is uniformly distributed throughout the carrier layer 109. The distributed pressure is then moved through the channels 324 to the underside 323 of the carrier layer, to uniformly distribute the pressure through the adjacent bioabsorbable layer.

[00145] The carrier layer may be partially or fully adhered to the bioabsorbable layer or may have a non-adherent surface. In addition, ear elements of the bioabsorbable layer may be inserted into the foam to mechanically hold the two components together. Fluid conduit

[00146] Fluid conduit 111 comprises a flexible tube, for example, a tube with a plastic or elastomeric wall. The tube may have sufficient wall thickness to prevent the walls from collapsing under applied negative pressure, for example, from 50 to 250 mm Hg, or up to 650 mm Hg. Suitable conduits used for wound therapy purposes are apparent to those skilled in the art. Alternatively, conduit 111 may comprise a thin wall supported by a support frame or other material or structure to prevent the tube walls from collapsing under negative pressure. For example, conduit 111 may comprise a tube comprising a membrane or thin wall surrounding a resilient coil or open-cell foam or three-dimensional tissue or matrix.

[00147] One end of conduit 111 is configured for attachment to a negative pressure source such as a pump (not shown) or another pressure wound therapy system. Petition 870260051284, dated 05 / 28 / 2026, page 39 / 129 34 / 51 common negative. For example, conduit 111 may have an end coupling such as a luer connector or a threaded connector for attachment to a negative pressure source. Alternatively, conduit 111 may be sized to receive or be received by an appropriate connector such as should be apparent to a person skilled in the art.

[00148] A second end 112 of the conduit 111 is in fluid communication with the carrier layer 109 and is arranged to apply pressure to the carrier layer 109. In the embodiment shown in Figures 3 and 4, the second end 112 of the conduit is positioned between the occlusive layer 107 and the carrier layer 109. A distal end of the conduit 111 extends into an opening formed between the occlusive layer 107 and the patient. In some embodiments, the distal end of the conduit 111 may be fixed to the patient's skin to reduce the risk of the second distal end of the conduit being inadvertently pulled from the dressing 101. For example, the distal end of the conduit 111 may be fixed by using a piece of adhesive tape 131 placed over the conduit 111 and adhered to the skin. In the embodiment shown, the adhesive tape is positioned between the edge of the pressure distribution layer 106 and the adjacent edge of the occlusive layer 107 and covered by the occlusive layer 107.

[00149] Figures 35 (i) and 35 (ii) illustrate a sleeve form 132 comprising a passage 137 for receiving a portion of the conduit 111. The sleeve 132 forms a separator that defines a negative pressure region on one side of the sleeve and an ambient pressure region on the other side of the sleeve 132. A hermetic seal can be formed between the outer surface of the conduit 111 and the inner surface of the passage 137, such as by fixing the conduit 111 to the sleeve 132 by means of bonding, welding or adhesion of the conduit to the sleeve. The underside, or skin contact side, of the sleeve may comprise an adhesive layer 136 Petition 870260051284, dated 05 / 28 / 2026, page 40 / 129 35 / 51 such as a medical-grade acrylic-based pressure-sensitive adhesive, a silicone gel adhesive, or another suitable adhesive material to aid in locating and securing the conduit and glove to the skin. In some forms, the glove comprises an elastomeric material to provide a flexing and gripping element.

[00150] Alternatively, the occlusive layer 107 may comprise an opening and the second distal end 112 of the conduit 111 may terminate on the upper surface of the occlusive layer 107 so as to apply negative pressure through the underside of the occlusive layer and those layers below the occlusive layer, in a manner similar to the dressing arrangement shown in Figure 2. Alternatively, the distal end of the conduit 111 may extend through an opening in the occlusive layer 107 to apply negative pressure through the layers of the wound dressing below the occlusive layer. In some embodiments, the occlusive layer is sealed at the distal end of the conduit to prevent fluid leakage.

[00151] The conduit 111 may comprise a double-lumen conduit having a primary lumen 133 for applying negative pressure to the dressing and one or more secondary lumens 134. The secondary lumens 134 may be used to introduce fluid into the wound site or to allow measurement and monitoring of pressure within the dressing. Alternative embodiments may instead comprise a plurality of conduits for introducing fluid into the wound site and monitoring pressure across the site.

[00152] In the embodiment shown in Figure 34, the duct 111 comprises a primary lumen 133 and a smaller secondary lumen 134 arranged side by side. The primary lumen 133 has an elliptical profile with a major axis length of about 4.5 mm and a minor axis length of about 3.8 mm, while the secondary lumen 134 has a circular profile of about 1.5 mm in diameter. The open area of Petition 870260051284, dated 05 / 28 / 2026, p. 41 / 129 The primary lumen 133 is approximately 10 mm2, while the open area of ​​the secondary lumen is approximately 2 mm2. The elliptical profile of this embodiment, coupled with the side-by-side arrangement, lends itself to ensuring that the conduit 111 generally lies flat against the various contours of the body in situations where the negative pressure source is located away from the wound, and such a situation is likely when the wound is located on the forearm or lower leg regions of the body.

[00153] The double-lumen conduit 111 in this embodiment is preferably made of a medical-grade thermoplastic elastomer with a 'soft touch', preferably with a Durometer hardness between Shore 30 A and Shore 80 A, to ensure comfort against the skin and wound when pressure is applied to the dressing 101 during use, such as when a patient may lie on the dressing 101 for extended periods of time.

[00154] It is also important that the surface texture of the conduit material has a low coefficient of friction to prevent unwanted bioburden and the accumulation of particulates on the conduit surface, as is the case with polysiloxane (silicone) materials. However, the conduit can be made of any other readily available elastomeric material, such as thermoplastic polyurethane, synthetic rubber, silicone, or other plasticized synthetic polymers.

[00155] The embodiment in Figure 34 also incorporates an angled support 135 along the minor axis of the primary lumen 133 to prevent tube collapse when pressure is applied to the top of the conduit 111 or dressing 101, such as when a patient may be lying on the device. This support 135 gives the conduit a soft, conformable profile to reduce the risk of the conduit creating pressure-related injuries to the patient after prolonged localized compression between the patient's body and the conduit, particularly where the conduit comes into contact with the spine, hip, ankle, or knee. Petition 870260051284, dated 05 / 28 / 2026, page 42 / 129 37 / 51 or the shoulder.

[00156] The second distal end 112 of the conduit or a portion of the conduit adjacent to the second end 112 may have an enlarged open area to receive fluid into the conduit 111 and better distribute the pressure of the conduit 111 across the carrier layer. For example, the conduit may be provided with an elongated elliptical opening, such as by providing a tapered distal end 112. In some forms, the tapering of the distal end 112 may be gradual to such a point that it allows the distal end of the conduit to lie almost flat against an upper surface of one of the layers of the wound dressing, such as the occlusive layer 107. This enlarged open area of ​​the distal end reduces the likelihood of the conduit becoming blocked at the distal end 112 and also helps in the distribution of negative pressure across the surface of the carrier layer.In alternative modalities, the conduit may comprise a series of teeth within the internal lumen of the conduit, so that if a portion of the conduit wall is cut to obtain a tapered distal end 112, the teeth are exposed and prevent the collapse of the remaining portion of the tube wall under compression. This may also reduce point loading of the conduit on the wound, which is a limitation of the existing prior technique (Figure 2), and which may cause the conduit port to be pressed against the wound and cause pain.

[00157] With reference to the alternative embodiment shown in Figures 34, 36 (i) and 36 (ii), the conduit 111 comprises a double-lumen conduit where the elongated opening at the distal end 112 is formed by removing an 'L' extension of the conduit that extends from an area near the elastomer sleeve 132 to the terminal end point of the distal end 112 of the conduit. In effect, the distal end portion 'L' of the double-lumen conduit is opened along the underside to expose each of the lumens to the upper surface of the dressing layer. Petition 870260051284, dated 05 / 28 / 2026, p. 43 / 129 38 / 51 This arrangement is preferably oriented to preserve the support 135 of the double-lumen conduit, to help prevent collapse of the remaining portion of the conduit, and to expose the secondary lumen 134 along the same 'L' length. The exposed inner surface of the 'L' end portion should be provided with a length sufficient to extend substantially through the longest axis of the wound and to facilitate the distribution of negative pressure across the uppermost surface of the carrier layer. Provided the double-lumen conduit is sufficiently flexible, the conduit 111 can be positioned in any shape or pattern across the top of the carrier layer to ensure adequate distribution of the applied negative pressure.

[00158] In the embodiment shown in Figures 3 and 4, the distal end portion of the conduit, adjacent to the second distal end 112, is substantially arch-shaped, with the underside of the arch open to the top of the carrier layer 109. In this embodiment, the length of the arched end portion of the conduit is about 30% of the dressing width, but in the alternative embodiment, the length of the end portion can be between about 20% and about 90% of the dressing width 101.

[00159] In an alternative embodiment, the second distal end 112 may divide into a plurality of branches, each of which extends in different directions across the upper surface of the carrier layer 109 to aid in pressure distribution and fluid reception into the conduit 111 across the entire area of ​​the carrier layer 109. Each of these branches may have an internal diameter similar to or smaller than the main conduit 111, and may comprise an arched portion with a downside in fluid communication with the carrier layer 109. Pressure distribution layer

[00160] Optionally, the dressing may comprise a layer Petition 870260051284, dated 05 / 28 / 2026, page 44 / 129 39 / 51 additional between the carrier layer and the occlusive layer. Figures 31 to 33 show such alternative modal dressings 1201, 1301. The additional layer is a pressure distribution layer 1206 to distribute the pressure applied by the conduit 1211 substantially across the entire surface of the underlying carrier layer 1209, 1309. The pressure distribution layer 1206, 1306 rests directly on the carrier layer 1209, 1309, between the carrier layer and the occlusive layer 1207, 1307.

[00161] The pressure distribution layer 1206, 1306 is flexible and compressible to conform to and cushion the wound site. The pressure distribution layer 1206, 1306 has an open shape that defines multiple fluid passages between the conduit 111 and the carrier layer 1209, 1309 to minimize pressure drop across the thickness of the pressure distribution layer 1206, 1306. As examples, the pressure distribution layer 1206, 1306 may comprise an open-cell foam or a three-dimensional fabric, such as a spacer fabric. The opening of the pressure distribution layer 106 is larger than the opening of the carrier layer material 1209, 1309, and the opening at least partially compensates for the pressure drop from using a more closed material such as silicone foam for the carrier layer.

[00162] In the embodiments shown, the pressure distribution layer 1206, 1306 comprises a three-dimensional braided polyethylene fabric. The braided layer has an open shape that defines an interlacing of the pressure distribution channels between the lines that form the fabric. Multidirectional flow passages ensure that fluid flow can always flow through the layer even if some passages become blocked.

[00163] Optionally, the pressure distribution layer 1206 may comprise an arrangement of pressure distribution channels. Petition 870260051284, dated 05 / 28 / 2026, page 45 / 129 40 / 51 interconnected 1208 that are substantially perpendicular to the interface between the carrier layer 1209, 1309 and the pressure distribution layer 1206, 1306. Fluid flow can occur along these vertical channels, but also laterally between the channels, i.e., between the lines that form the fabric. In alternative embodiments, the pressure distribution layer may comprise an open-cell foam, for example, a cross-linked foam. Occlusive layer

[00164] The occlusive layer 107 is substantially impermeable to liquids and substantially impermeable to air. Preferably, the occlusive layer 107 has a high water vapor transmission rate (WVTR), also known as moisture vapor transmission rate (MVTR), to provide a sealed environment for the application of negative pressure, but to allow moisture to pass through the dressing. This helps prevent maceration of the periphery of the intact wound and also allows excess fluid and exudate to be expelled from the wound environment. One underside of the occlusive layer 107 optionally comprises an adhesive surface for removablely adhering a peripheral portion of the dressing 101 to a patient's skin to seal the wound cavity and thereby allow control of pressure within the cavity.

[00165] The surface area of ​​the occlusive layer 107 is preferably larger than that of the underlying bioabsorbable and carrier layers 105, 109, with the peripheral portion of the occlusive layer 107 optionally forming an adhesive flap 108 to adhere to the periphery of the wound 104 to fix the dressing in place. In some embodiments, the adhesive dressing may only be applied to the underside (patient contact side) of this adhesive flap 108.

[00166] The adhesive surface of the occlusive layer can be created by applying an adhesive coating to all or part of it. Petition 870260051284, dated 05 / 28 / 2026, page 46 / 129 41 / 51 peripheral underside (patient contact side) of occlusive layer 107. Where the adhesive backing is applied to the entire underside of the occlusive layer, the occlusive layer 107 may optionally be bonded to the carrier layer 1091.

[00167] In other forms, an adhesive or a sealant may be applied separately around the periphery of the occlusive layer, or a sealant layer may be placed over the occlusive layer so as to extend beyond the periphery of the occlusive layer to adhere and seal the wound dressing to the patient's skin.

[00168] The occlusive layer 107 may be substantially transparent or may comprise a transparent region to allow monitoring of the underlying layers. In one embodiment, the carrier layer 109 comprises one or more viewing openings located below the transparent region to allow at least visual inspection of a portion of the bioabsorbable layer. This may aid in monitoring the progress of wound healing.

[00169] In the embodiment shown, the occlusive layer 107 is a thin transparent polyurethane-based sheet (e.g., about 15 to 60 µm thick, preferably about 20 µm thick, to provide good MVTR while still being easy to pick up), and has a 20 to 80 µm thick layer of silicone adhesive applied to the underside. Alternative adhesives include modified rubber-based adhesives and pressure-sensitive acrylic adhesives, or a combination thereof. Moldable seal

[00170] To improve the liquid impermeability of the seal between the dressing and the patient's skin surface, and to protect the area at the periphery of the wound 104, a moldable seal / adhesive 129 may be placed around the perimeter of the wound, but preferably within the boundary of the occlusive layer 107. The occlusive layer 107 is placed Petition 870260051284, dated 05 / 28 / 2026, p. 47 / 129 42 / 51 typically over the moldable seal / adhesive 129 and adheres to the skin around the outer part of the area defined by the moldable strip 129. In another form, the moldable seal can be placed over and around the periphery of the occlusive layer 107 to seal against the occlusive layer and the patient's skin.

[00171] A moldable sealant / adhesive may comprise a non-curable moldable material. Typically, a moldable sealant comprises a homogeneous material in which the adhesive strength is generally consistent throughout the material. This allows the material to be stretched, deformed, kneaded, and manipulated to create any shape while maintaining a high level of adhesive strength. Consequently, the moldable sealant / adhesive may be repositionable, deformable, and stretchable.

[00172] In the embodiments shown, the moldable seal comprises a butyl rubber-based adhesive component. The component comprises synthetically obtained butyl rubber that has been mixed with a tackifying resin agent, an organic filler to weaken the rubber compound into a uniquely soft tacky form, and optionally a stabilizing agent. In the preferred embodiment, the compound consists of polyisobutylene, an aliphatic hydrocarbon resin as a tackifying agent, calcium carbonate as a filler material, and poly(dicyclopentadiene-co-p-cresol) as a stabilizing agent. Alternatively, any suitable hypoallergenic tackifying resin may be used during the mixing and extrusion process to obtain the sealing material, while other filler materials may include talc, dolomite, barite, kaolin, and silica.In alternative embodiments, the moldable seal may comprise alternative moldable adhesives or alternative rubber sources, such as moldable polysiloxane (silicone), styrene butadiene, polychloroprene (neoprene), nitrile rubber, or... Petition 870260051284, dated 05 / 28 / 2026, page 48 / 129 43 / 51 compounds that include mixtures of the aforementioned synthetic rubbers.

[00173] The moldable seal / adhesive 129 offers several other advantages such as high levels of skin adhesion with a low level of trauma or pain during removal. The adhesive properties of the moldable seal can be adjusted by varying the amount of tackifying agent added during the mixing and extrusion process, which can be adjusted to obtain adhesion properties comparable to acrylic-based pressure-sensitive adhesives typically used for dressings and medical devices to achieve high skin adhesion. Unlike coated adhesive dressings, the moldable seal / adhesive 129 can be stretched from the skin after use to break the adhesion between the adhesive surface of the seal and the skin. The moldable seal / adhesive 129 is also removable and repositionable on the skin while retaining a high level of adhesive strength.

[00174] Another advantage of the moldable sealant / adhesive 129 is the possibility of directly applying release agents comprising isopropyl alcohol (IPA), hexamethyl disiloxane, 1,1,1,2-tetrafluoroethane, ISOPARAFFIN L, (2-methoxymethylethoxy)propanol, hydrotreated heavy naphtha (petroleum) or a mixture of the agents to the moldable sealant / adhesive 129 as needed during dressing removal.

[00175] Other advantages of the moldable sealant / adhesive 129 include its thickness and softness, which allow the sealant material to be compressed and molded into the folds and crevices of the skin that are common in patients and that can lead to leaks and subsequent loss of negative pressure to the wound, as shown in Figure 29, if an ineffective seal is formed between the dressing and the skin. The softness of the moldable sealant / adhesive can also be adjusted by changing the Petition 870260051284, dated 05 / 28 / 2026, p. 49 / 129 44 / 51 Rubber material used during the mixing and extrusion process. The amount of filler added during manufacturing can increase or decrease the softness of the moldable seal / adhesive.

[00176] The moldable seal 129 can be provided in a strip form. In some forms, the seal is provided in a strip comprising a width of about 10 mm, a thickness of about 3 mm and a length of about 250 mm. In some forms, the seal strip can then be provided in any widths ranging from about 5 mm to about 30 mm and with thicknesses ranging from about 2 mm to about 8 mm, and a length ranging from about 50 mm to about 400 mm. In some forms, the moldable seal 129 can be provided in a roll with a total length ranging from about 200 mm to about 5,000 mm. In some forms, the seal can be manually formed into a desired shape from a block of moldable material, such as by shaping the material as an elongated strip in the shape of a long sausage.

[00177] In some embodiments, an elongated flattened strip of moldable material is provided in a first removable release sheet, which is adhered to one side of the moldable strip 129. A second removable release sheet is adhered to the opposite second side of the moldable strip, such that the moldable strip is sandwiched between the release sheets. In other embodiments, the moldable adhesive 129 is provided in a roll with the release sheets attached to both sides of the overlapping surfaces of the roll.

[00178] The first removable release sheet may be a paper-based material or any other suitable material, such as a plastic material, which is attached to a first surface of the moldable strip, i.e., the patient contact side of the moldable strip. This first removable release sheet protects the moldable strip during storage and handling and is removable to expose a first surface. Petition 870260051284, dated 05 / 28 / 2026, page 50 / 129 45 / 51 surface of the moldable sealing strip. The surface of the paper-based material that comes into contact with the moldable strip may be coated with a release coating, such as silicone or any other release agents such as polytetrafluoroethylene (PTFE), to reduce adhesion between the first removable release sheet and the moldable strip for easy removal of the first release sheet.

[00179] The second removable release sheet adheres to a second surface of the moldable strip opposite the first surface. This second removable release sheet protects the moldable strip during placement of the strip around the wound. The second removable release sheet is preferably a thin, flexible sheet of silicone or any other suitable material that can stretch along with the moldable strip 129 to allow the moldable strip to be manipulated and shaped as needed to conform to the wound periphery site without removing the second release sheet. The surface of the second release sheet that contacts the moldable strip may be coated with a release liner to reduce adhesion between the second removable sheet and the moldable strip for easy removal of the second release sheet.

[00180] The second release sheet is preferably transparent or semi-transparent, such that the skin surface to which the moldable strip is being applied is visible to the clinician during application in order to assist with application. For example, the second removable release sheet may comprise a silicone sheet.

[00181] The second removable release sheet is removed from the moldable strip after the moldable strip is applied to the patient, thereby eliminating the need for a medical professional to touch the surface of the moldable strip to apply it.

[00182] A removable protective sheet is attached to the second removable release sheet to protect the second release sheet. Petition 870260051284, dated 05 / 28 / 2026, page 51 / 129 46 / 51 removable during transport. This protective sheet may be a paper-based material or may be of any other suitable material, such as a plastic material that is removable to expose the second release sheet. Applying and removing the dressing

[00183] Dressings 101, 201, 401 described above and other embodiments thereof are suitable for use in the treatment of chronic wounds, for example, diabetic ulcers and burns. Figures 25 and 26 illustrate dressing 101 applied to a wound on the foot and a wound on the arm, respectively.

[00184] To apply the dressing, the moldable material is first applied around the periphery of the wound as described above. The moldable material is pressed into the skin 104 surrounding the wound, thereby filling the undulations and creases of the skin as illustrated in Figure 29, to act as a skin barrier and reduce fluid leakage from the dressing.

[00185] The bioabsorbable layer 105 is then adjusted over the wound surface in full contact with the surface and following the contours of the wound. The carrier layer 109 is then placed over the bioabsorbable layer, the conduit 111 is fixed in place over the carrier layer 109, and the arrangement is then covered by the occlusive layer and sealed to ensure that the wound is airtight.

[00186] The first end of conduit 111 is coupled to a negative pressure source such as a vacuum pump, and the pump is operated to create a continuous or intermittent vacuum within the sealed dressing. The negative pressure helps in removing fluid from the wound and can improve circulation to enhance wound healing.

[00187] To remove the dressing, the occlusive layer 107 is torn from the skin, and the conduit 111 and carrier layer 109 are removed. The vacuum pump may include a reservoir to collect the Petition 870260051284, dated 05 / 28 / 2026, page 52 / 129 47 / 51 exudate fluids removed from the dressing.

[00188] With regard to Figures 26, 28 and 30, in a final step, the moldable seal 129 can be removed from the patient's skin by stretching the moldable seal in a longitudinal direction as illustrated. When the seal is stretched, it is gently released from the patient's skin 104, minimizing the likelihood of skin damage.

[00189] The bioabsorbable layer does not need to be removed from the wound, as it breaks down naturally over time. EXAMPLES Example 1: Manufacturing method

[00190] A bioabsorbable layer 105 with x-shaped openings 119 was prepared according to the following method. With reference to Figures 39 to 41, a sheet of reticulated tissue was prepared according to the method described in patent application PCT / NZ2009 / 000152 for the provision of a material 95 for processing when using a cutting / punching apparatus 89.

[00191] The cutting apparatus 89 includes an upper press assembly comprising a punch retainer plate 92, a punch pin assembly 99 and a retainer plate 90. The punch pin assembly 99 includes a punch 93 which is formed to produce the desired end opening, and a punch pin retainer 91.

[00192] In this example, the punch 93 is formed to produce the x 119 shaped opening shown in Figure 16 (i) and has a width and height of about 5.5 mm with a notch thickness or width of about 0.5 mm.

[00193] The cutting apparatus 89 includes a press plate 94, which is aligned to pass along the same axis as the upper press assembly, defined by the punch retainer plate 92, the punch pin assembly 99 and a retaining plate. Petition 870260051284, dated 05 / 28 / 2026, p. 53 / 129 48 / 51 90, and the lower die plate 97, which is retained by a die nest 98.

[00194] The punch retaining plate 92, the press plate 94 and the lower die plate 97 are aligned with high precision to ensure tight spacing with the punch 93 as it moves through the press plate 94 of the lower die plate 97 during the cutting / punching process.

[00195] With reference to Figure 41(i), the cutting material 95 is placed on the lower die plate 97 of the die and the pressure plate 94 and the upper pressure plate assembly is contracted to advance the punch 93. The press plate 94 engages with the material 95 to firmly hold the sheet in place while the upper press assembly continues to advance.

[00196] Figure 41(ii) illustrates the punch 93 passing through the material 95 to cut / puncture a rod 96 of material, thereby forming the opening 119 in the material 95. In other words, gaps are formed in the bioabsorbable material layer by removing a rod from the material layer. The material 95 is then positioned, or moved in a transverse direction, to repeat the process until the required number of openings 119 is formed in the material. Example 2: Measuring the pressure drop across multiple bioabsorbable layers.

[00197] The following example outlines the apparatus and test method used to evaluate and compare the pressure drop through various materials and different forms of bioabsorbable layers. With reference to Figure 42, a pressure drop test apparatus 79 was constructed, comprising a base plate 81, a base support 80, and a clamping ring 86. The clamping ring 86 includes a peripheral groove (not shown in Figure 42) to accommodate a rubber O-ring or other form of seal 85. Petition 870260051284, dated 05 / 28 / 2026, page 54 / 129 49 / 51

[00198] The base plate 81 includes two ports 82, each of which is connected to a separate pressure sensor. Each pressure sensor is capable of accurately measuring vacuum pressure across a range of 0 to 400 mm Hg. The pressure sensors are indicated in this document as measuring points P2 and P3. The two ports 82 are spaced approximately 45 mm apart. The base plate 81 may also include three spare ports 83 which are spaced approximately 45 mm apart from a central pressure measuring port 82.

[00199] A test specimen 84 was cut to fit within a central recess in the base plate 81 and subsequently secured in place by attaching the clamping ring 86 to the base plate 81 using the fastening components located around the periphery of the clamping ring 86 and the base plate 81.

[00200] Before proceeding further, the test specimen was rehydrated within the testing apparatus according to the manufacturer's instructions, and excess fluid was removed from the apparatus. For materials related to the invention described, the test specimens were rehydrated using a saline solution for approximately 5 minutes, and any excess fluid was removed from the apparatus before testing.

[00201] All tests were performed by placing a 100 mm x 100 mm piece of cross-linked open-cell polyurethane foam (VAC® GRANUFOAM® - KCI / Acelity®) into the central opening of the clamping ring 86, which was sized to ensure a tight fit consistent with the foam. Each test was then performed with an adhesive polyurethane dressing (VAC® Curtain - KCI / Acelity®) and the centrally positioned portal 87 (SENSAT.RACTMPad KCI / Acelity®) affixed over the top of the installation.

[00202] A 'y-shaped connector' was then attached to the portal. Petition 870260051284, dated 05 / 28 / 2026, p. 55 / 129 50 / 51 centrally positioned to allow one end of the conduit to be connected to a pressure sensor with the other end of the conduit being connected to a controlled negative pressure source. The pressure sensor placed next to the curtain is indicated in this document as measurement point P1. Before and after testing, the pressure sensors at measurement points P1, P2, and P3 were checked to ensure calibration was within specification.

[00203] Each test was then performed according to the following sequence: 1. Pressurize the measuring point P1 to the required pressure level. 2. Maintain pressure for 5 minutes to verify that the system is free of any leaks. 3. Maintain the pressure setpoint for an additional 5 minutes while recording the pressure at measurement points P1, P2, and P3 at 1-second intervals. 4. Repeat the test cycle 3 or more times for the same test specimen to establish average pressure measurements at the 3 measurement points (P1, P2 and P3). 5. Evaluate the data to determine if P1 was kept constant within ±5 mm Hg throughout the 5-minute data acquisition period (step 3 above). 6. Remove the test specimen and perform two more replicate tests on the same specimen to determine the pressure drop for each type of material.

[00204] The test was performed with four different materials where a 'foam only' test was performed as a control. The four different materials were denoted as follows: 1. DOUBLE LAYER CGAG - A bioengineered composite wound matrix comprising type 1 bovine collagen that was Petition 870260051284, dated 05 / 28 / 2026, page 56 / 129 51 / 51 cross-linked with glycosaminoglycan. This wound matrix was affixed to a silicone layer and fenestrated using a series of alternating linear cuts, similar to that in Figure 18. 2. CORC - a resorbable composite collagen dressing comprising 45% oxidized regenerated cellulose (ORC) and 55% collagen. 3. WITH 3-LAYER EAR - a multi-layered 3-layer bioabsorbable layer similar to that in Figure 14 (i), prepared according to the method described in patent application PCT / NZ2015 / 050215, using freeze-dried sheets of sheep gizzard matrix, or rumen originating from and processed according to patent application PCT / NZ2009 / 000152. 4. 3-LAYER EAR WITH OPENING - a 3-layer multi-layer bioabsorbable layer, the same as 3 above, wherein the layer comprised x-shaped openings prepared according to Example 1 with an opening geometry of 5 mm length x 5 mm width with a thickness or width of the slit of approximately 0.5 mm, wherein the openings were positioned in an alternating pattern with repeated openings positioned 20 mm apart on a first axis and 10 mm apart on a second axis that is perpendicular to the first axis.

[00205] Tests were performed at a vacuum pressure of 40 mm Hg and 200 mm Hg with the test results shown in Figure 43. Petition 870260051284, dated 05 / 28 / 2026, page 57 / 129

Claims

1 / 6 CLAIMS 1. Wound dressing (101, 201, 1201, 1301, 1401) for applying negative pressure to a wound (103, 503, 703, 803, 1203, 1303, 1403) comprising: a bioabsorbable graft layer (105, 205, 605, 705, 805, 1005, 1105, 1205, 1305, 1405) for placement in contact with the wound; a liquid-impermeable occlusive outer layer (107, 207, 1207, 1307, 1407); a porous fluid carrier layer (109, 209, 1209, 1309, 1409) positioned between the outer layer and the bioabsorbable graft layer; and a fluid conduit (111, 211, 1211, 1311, 1411) in fluid communication with the carrier layer (109, 209, 1209, 1309, 1409), for coupling to a negative pressure source; wherein the carrier layer comprises a multiplicity of fluid passages between the conduit and the bioabsorbable graft layer;characterized in that the bioabsorbable graft layer comprises a plurality of openings (119, 219, 619, 719, 819, 1019, 1119, 1219, 1319, 1419) to allow fluid flow from the wound to the carrier layer, each opening comprising one or more notches or slits that define one or more fins (121, 721, 821); wherein each fin is movable from a closed position, in which the entire fin is in contact with the wound, to an open position in order to increase the size of the respective opening.

2. Wound dressing according to claim 1, characterized in that the bioabsorbable graft layer (105, 205, 605, 705, 805, 1005, 1105, 1205, 1305, 1405) comprises a plurality of mechanically blocked bioabsorbable graft sheets (113a, 113b).

3. Wound dressing according to claim 1 or 2, characterized in that the bioabsorbable graft layer (105, 205, 605, 705, 805, 1005, 1105, 1205, 1305, 1405) comprises a first sheet (113a) having a plurality of ears (115) and a second sheet (113b) having a plurality of openings (117), wherein each ear of the first sheet is positioned through a respective opening (117) in the second sheet to lock the first sheet (113b) with the second sheet.

4. Wound dressing according to any of the preceding claims, characterized in that the bioabsorbable graft layer (105, 205, 605, 705, 805, 1005, 1105, 1205, 1305, 1405) comprises an extracellular matrix (ECM).

5. Wound dressing according to claim 4, characterized in that the ECM comprises a reticulum.

6. Wound dressing according to any one of claims 1 to 5, characterized in that each opening comprises two or more crossed notches or slits or one curved notch or slit.

7. Wound dressing according to any of the preceding claims, characterized in that the notches or slits (119, 219, 619, 719, 819, 1019, 1119, 1219, 1319, 1419) are in the shape of an X, in the shape of a Y, in the shape of a C, in the shape of a U, or in the shape of a V.

8. Wound dressing according to any of the preceding claims, characterized in that openings are formed through the bioabsorbable graft layer by removing a plug of material from the bioabsorbable graft layer.

9. Wound dressing according to any of the preceding claims, characterized in that the cracks or notches are cut by a matrix of the bioabsorbable graft layer.

10. Wound dressing according to any of the preceding claims, characterized in that the carrier layer (109, 209, 1209, 1309, 1409) comprises a fluid-permeable foam.

11. Wound dressing according to claim 10, characterized in that the carrier layer (109, 209, 1209, 1309, 1409) comprises a PVA foam.

12. Wound dressing according to any of the preceding claims, characterized in that the carrier layer (109, 209, 1209, 1309, 1409) is compliant and porous.

13. Wound dressing according to any of the preceding claims, characterized in that an upper surface of the carrier layer (109, 209, 1209, 1309, 1409) is wavy.

14. Wound dressing according to claim 10 or 11, characterized in that it also comprises a pressure distribution layer (106, 1206, 1306) between the carrier layer (109, 209, 1209, 1309, 1409) and the occlusive layer (107, 207, 1207, 1307, 1407).

15. Wound dressing according to claim 14, characterized in that the pressure distribution layer (106, 1206, 1306) comprises an open-cell foam or a three-dimensional fabric.

16. Wound dressing according to claim 14 or 15, characterized in that the pressure distribution layer (106, 1206, 1306) comprises a plurality of fluid flow channels (1208, 1308) that are perpendicular to the interface between the carrier layer (109, 209, 1209, 1309, 1409) and the pressure distribution layer to allow fluid to flow through the pressure distribution layer. Petition 870260051284, dated 05 / 28 / 2026, page 60 / 129 4 / 6 17. Wound dressing according to any of the preceding claims, characterized in that the conduit (111, 211, 1211, 1311, 1411) comprises a distal end portion (112, 212, 1212, 1312, 1412) having an opening in fluid communication with the carrier layer (109, 209, 1209, 1309, 1409).

18. Wound dressing according to claim 17, characterized in that the distal end portion is arc-shaped.

19. Wound dressing according to claim 17, characterized in that the conduit comprises a double lumen conduit (111, 1411) comprising a support (135) positioned along a central axis of one of the lumens to prevent the conduit from collapsing under compression.

20. Wound dressing according to claim 19, characterized in that the conduit comprises a lumen that is elliptically shaped.

21. Wound dressing according to any of the preceding claims, characterized in that the conduit is a double lumen conduit (111, 1411) comprising a primary conduit (133) for applying negative pressure to the dressing and a secondary conduit (134) for introducing fluid into the dressing or for facilitating pressure measurement.

22. Wound dressing according to any of the preceding claims, characterized in that it also comprises a sleeve (132) comprising a port for receiving a portion of the conduit (111) therein in an arrangement secure for attaching the conduit to the dressing.

23. Wound dressing according to claim 22, characterized in that the glove (132) comprises an elastomeric material. Petition 870260051284, dated 05 / 28 / 2026, page 61 / 129 5 / 6 24. Wound dressing according to claim 22 or 23, characterized in that the sleeve (132) forms a divider between a negative pressure receiving area of ​​the dressing and an ambient pressure area.

25. Wound dressing according to any of the preceding claims, characterized in that the occlusive layer (107, 207, 1207, 1307, 1407) comprises a transparent region and the carrier layer (109, 209, 1209, 1309, 1409) comprises one or more viewing openings to allow visual inspection of a portion of the bioabsorbable graft layer (105, 205, 605, 705, 805, 1005, 1105, 1205, 1305, 1405).

26. Wound dressing according to any of the preceding claims, characterized in that the occlusive layer (107, 207, 1207, 1307, 1407) comprises a polyurethane sheet comprising an adhesive surface.

27. Wound dressing according to any of the preceding claims, characterized in that it comprises a moldable adhesive seal for surrounding a wound, wherein the seal comprises butyl rubber, a filler, and a tackifying resin.

28. Wound dressing according to claim 27, characterized in that the moldable adhesive seal is removable and resealable against a patient's skin.

29. Wound dressing according to claim 27 or 28, characterized in that the moldable adhesive seal is not curable.

30. Wound dressing according to any one of claims 27 to 29, characterized in that the seal is removable from a skin surface by stretching the adhered seal. Petition 870260051284, dated 05 / 28 / 2026, p. 62 / 129 6 / 6 31. Wound dressing according to any of the preceding claims, characterized in that the bioabsorbable graft layer (105, 205, 605, 705, 805, 1005, 1105, 1205, 1305, 1405) comprises a multiplicity of perforations and / or microchannels (117, 117').

32. Wound treatment system, characterized in that it comprises the wound dressing (101, 201, 1201, 1301, 1401) as defined in any one of claims 1 to 30 and the moldable adhesive seal (129, 229, 1229, 1329, 1429) suitable for application around the perimeter of the patient's wound, wherein the seal is suitable for removal and resealing against a patient and optionally comprises butyl rubber, a filler and a tackifying resin; wherein the occlusive layer is suitable for being adhered over the moldable adhesive seal.

33. Wound treatment system according to claim 32, characterized in that the occlusive layer is adhered onto the moldable adhesive seal.

34. Wound treatment system comprising the wound dressing (101, 201, 1201, 1301, 1401) as defined in any one of claims 1 to 31, characterized in that a negative pressure source is coupled to the conduit to apply negative pressure to the wound (103, 503, 703, 803, 1203, 1303, 1403).

35. Wound treatment system according to any one of claims 32 to 34, characterized in that it also comprises a reservoir for collecting exudate removed from the dressing. Petition 870260051284, dated 05 / 28 / 2026, pp. 63 / 129

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