Note: Descriptions are shown in the official language in which they were submitted.
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SPECIFICATION
PRE-SHAPED ALLOGRAFT IMPLANT FOR RECONSTRUCTIVE SURGICAL USE
AND METHODS OF MANUFACTURE AND USE, AND TOOLS FOR FORMING
Background
[0001] An allograft includes bone, tendon, skin, or other types
of tissue that is
transplanted from one person to another. Allog rafts are used in a variety of
medical treatments, such as knee replacements, bone grafts, spinal fusions,
eye
surgery, and skin grafts for reconstructive surgery and for the severely
burned.
Allografts come from voluntarily donated human tissue obtained from cadaveric
donor-derived, living-related, or living-unrelated donors and can help
patients
regain mobility, restore function, enjoy a better quality of life, and even
save lives
in the case of cardiovascular tissue or skin.
[0002] An acellular dermal matrix (ADM) graft is a soft
connective tissue graft
generated by a decellularization process that preserves the intact
extracellular
skin matrix. Upon implantation, the ADM structure serves as a scaffold for
donor-
side cells to facilitate subsequent incorporation and revascularization. ADMs
are
manufactured utilizing known methods of decellularization by means of ionic
and
nonionic detergent methods, as well as those utilizing enzymatic processes and
other techniques such as those listed in "Decellularization of Tissues and
Organs,"
Gilbert, et al, 2006 (https://www.ncbi.nlm.nih.gov/pubmed/16519932).
[0003] Currently, ADM grafts are primarily derived from
decellularized
cadaveric skin and must be shaped and/or cut as necessary by the surgeon
either
prior to or during a surgical procedure. Such grafts are also commonly formed
from solid or perforated ADM. As a result, existing ADM grafts present
efficiency,
efficacy, and repeatability challenges when used for reconstructive surgery
purposes.
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Summary
[0004] This Summary is provided to introduce a selection of
concepts in a
simplified form that are further described below in the Detailed Description.
This
Summary is not intended to identify key aspects or essential aspects of the
claimed subject matter. Moreover, this Summary is not intended for use as an
aid
in determining the scope of the claimed subject matter.
[0005] One embodiment provides a method of manufacturing an
acellular
dermal matrix (ADM) graft product for use in a reconstructive surgical
procedure.
The method may include the following steps: (1) providing a portion of donor-
derived skin, the portion of the donor-derived skin having a full thickness;
(2)
removing an epidermis layer and a fat layer from the portion of the donor-
derived
skin to form a portion of dermal tissue; (3) decellularizing the portion of
the dermal
tissue to form a portion of ADM graft material; (4) forming the portion of the
ADM
graft material into a pre-defined shape in anticipation of the reconstructive
surgical
procedure; (5) fenestrating the pre-defined shape into a mesh pattern; (6)
verifying
that a thickness of the pre-defined shape equals a specified thickness; (7)
packaging the pre-defined shape in a medical sterilization pouch to form a
packaged, pre-shaped, and meshed ADM graft; and (8) irradiating the packaged,
pre-shaped, and meshed ADM graft to a sterility assurance level of 10-6 to
form
the ADM graft product.
[0006] Another embodiment provides a pre-shaped, meshed
acellular dermal
matrix (ADM) graft stored as a packaged graft product prepared by a process
comprising the steps of: (1) providing a portion of ADM tissue having a
thickness
between 1 mm and 2 mm; (2) fenestrating the portion of the ADM tissue in a
mesh
pattern extending over an entirety of the portion of the ADM tissue; (3)
scoring the
portion of the ADM tissue into a pre-defined shape to form the pre-shaped,
meshed ADM graft; (4) verifying the thickness of the pre-shaped, meshed ADM
graft; (5) packaging the pre-shaped, meshed ADM graft in a medical
sterilization
pouch; and (6) irradiating the pre-shaped, meshed ADM graft within the medical
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sterilization pouch to a sterility assurance level of 10-6 to form the
packaged graft
product.
[0007] Yet another embodiment provides an acellular dermal
matrix (ADM)
graft product. The ADM graft product may include an ADM graft derived from
full-
thickness skin, the ADM graft having a pre-formed shape with a mesh pattern
formed therein, as well as a medical sterilization pouch sealed about the ADM
graft, wherein when the medical sterilization pouch and the ADM graft are
irradiated to a sterility assurance level of 10-6, the ADM graft product has a
shelf-
life of two years.
[0008] In yet another embodiment, there is provided a method of
manufacturing an acellular dermal matrix (ADM) graft product for use in a
reconstructive surgical procedure. The method may include providing a portion
of
donor-derived skin, the portion of the donor-derived skin having a full
thickness.
The method may include removing an epidermis layer and a fat layer from the
portion of the donor-derived skin to form a portion of dermal tissue. The
method
may include decellularizing the portion of the dermal tissue to form a portion
of
ADM graft material. The method may include forming the portion of the ADM
graft
material into a pre-defined shape in anticipation of the reconstructive
surgical
procedure, and the forming the portion of the ADM graft material into the pre-
defined shape comprises at least one of scoring and cutting the portion of the
ADM graft material into a domed shape ADM graft. The method may include
verifying that a thickness of the pre-defined shape equals a specified
thickness.
The method may include packaging the domed shape ADM graft in a medical
sterilization pouch to form a packaged and domed shape ADM graft. The method
may include irradiating the packaged and domed shaped ADM graft to a sterility
assurance level of 10-6 to form the ADM graft product.
[0009] In still another embodiment there is provided a domed
shaped acellular
dermal matrix (ADM) graft stored as a packaged graft product prepared by a
process. The process may include a step of providing a portion of ADM tissue
having a thickness between 1 mm and 2 mm. The process may include a step of
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scoring the portion of the ADM tissue into a pre-defined shape to form the
domed
shape ADM graft. The process may include a step of verifying the thickness of
the
domed shape ADM graft. The process may include a step of packaging the
domed shaped ADM graft in a medical sterilization pouch. The process may
include a step of irradiating the domed shaped ADM graft within the medical
sterilization pouch to a sterility assurance level of 10-6 to form the
packaged graft
product.
[0010] And in yet another embodiment there is provided a tool or
set of tools
having a set of features for forming a domed ADM graft. The set of features
may
include a shaping tool feature having a shaping portion configured to shape a
dome shaped ADM graft. The set of features may include a scoring tool feature
having a scoring portion configured to impart a desired mesh pattern into the
domed shaped ADM graft.
[0011] Other embodiments provide an ADM graft that combines the
ADM as
designed with antimicrobial elements that mitigate or prevent complications
arising
from post-surgical infections. Antimicrobial agents that are compatible with
the
ADM include silver in its colloidal, elemental or ionic form. The silver may
be
complexed with chelating agents or may be added directly to the ADM prior to
final packaging. Similarly other antimicrobial agents may be combined with the
ADM. Other agents well known to be used medically are chlorhexidine gluconate
and antimicrobial peptides of various amino acid chain length.
[0012] Other embodiments are also disclosed.
[0013] Additional objects, advantages and novel features of the
technology will
be set forth in part in the description which follows, and in part will become
more
apparent to those skilled in the art upon examination of the following, or may
be
learned from practice of the technology.
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Brief Description of the Drawings
[0014] Non-limiting and non-exhaustive embodiments of the
present invention,
including the preferred embodiment, are described with reference to the
following
figures, wherein like reference numerals refer to like parts throughout the
various
views unless otherwise specified. Illustrative embodiments of the invention
are
illustrated in the drawings, in which:
[0015] FIGURES 1A-1B illustrate respective front-plan and
perspective views
of one embodiment of a pre-shaped, meshed acellular dermal matrix (ADM) graft
derived from full-thickness skin;
[0016] FIGURES 2A-2B illustrate respective top-perspective and
bottom-
perspective views of one embodiment of scoring tool for manufacturing the pre-
shaped, meshed ADM graft of FIGURES 1A-1B;
[0017] FIGURES 3A-3B illustrate front-plan views of an exemplary
mesh, or
fenestration, pattern of the pre-shaped, meshed ADM graft of FIGURES 1A-1B,
shown in an open position and in a resting position, respectively;
[0018] FIGURE 4 illustrates a perspective view of an exemplary
skin mesher
for forming the mesh pattern of FIGURES 3A-3B;
[0019] FIGURE 5 illustrates a first perforated prior art ADM
graft for
comparison to the pre-shaped, meshed ADM graft of FIGURES 1A-1B;
[0020] FIGURE 6 illustrates a second perforated prior art ADM
graft for
comparison to the pre-shaped, meshed ADM graft of FIGURES 1A-1B;
[0021] FIGURES 7A-7B illustrate perspective views of a fluid
egress testing
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device in respective first and second stages of fluid egress testing of the
pre-
shaped, meshed ADM graft of FIGURES 1A-1B, the first perforated ADM graft of
FIGURE 5, and the second perforated ADM graft of FIGURE 6;
[0022] FIGURES 8A-8B provide a table reflecting multiple sets of
drainage
time measurements captured during the fluid egress testing performed using the
testing device of FIGURES 7A-7B;
[0023] FIGURE 9 provides a summary graft of the drainage time
measurements shown in FIGURES 8A-8B;
[0024] FIGURE 10 illustrates a front perspective view of an ADM
graft pocket
formed by joining two of the pre-shaped, meshed ADM grafts of FIGURES 1A-1B
together;
[0025] FIGURE 11 illustrates a front view of a pre-shaped,
meshed ADM graft
product in which the pre-shaped, meshed ADM graft of FIGURES 1A-2A is
packaged for storage in a sealed medical sterilization pouch;
[0026] FIGURE 12 illustrates the pre-shaped, meshed ADM graft
product of
FIGURE 11 further packaged in a medical peel pouch;
[0027] FIGURE 13 provides a flowchart depicting an exemplary
method of
manufacturing an embodiment of the pre-shaped, meshed ADM graft of FIGURES
1A-1B and the packaged ADM graft product of FIGURES 11-12;
[0028] FIGURE 14 is a photograph of an embodiment of a domed
shaped
ADM graft product;
[0029] FIGURES 15A and 15B illustrate an embodiment of a shaping
and
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scoring tool for manufacturing of the domed shaped ADM graft product of FIGURE
15; and
[0030] FIGURE 16 illustrates an alternative embodiment of a
domed shaped
ADM graft product having a multi-notched peripheral edge.
Detailed Description
[0031] Embodiments are described more fully below in sufficient
detail to
enable those skilled in the art to practice the system and method. However,
embodiments may be implemented in many different forms and should not be
construed as being limited to the embodiments set forth herein. The following
detailed description is, therefore, not to be taken in a limiting sense.
[0032] Various embodiments of the products and associated
methods of
manufacture and use described herein relate to a pre-shaped, meshed or
fenestrated acellular dermal matrix (ADM) graft derived from full-thickness
human,
donor-derived skin for use in the surgical reconstruction of soft tissue
defects
resulting from trauma, disease, or surgical intervention. For example,
embodiments of the ADM graft discussed herein may be used in the surgical
specialty of plastic surgery, and particularly in prepectoral and post-
mastectomy
breast reconstruction, where the ADM graft is an adjunct to integumental
repair of
the surgical site.
[0033] Embodiments of the ADM graft may be packaged and
irradiated for
long-term sterile storage in a manner that allows them to be used in surgical
procedures within two years of packaging. In use, embodiments of the pre-
shaped, meshed ADM graft provide the surgeon with a mechanism to restore
function to and support integumental tissue after surgical intervention in a
manner
that is repeatable, effective, and time efficient by leveraging a
manufactured, pre-
shaped and meshed ADM graft product that is derived from full-thickness skin.
Embodiments of the ADM graft facilitate fluid drainage from the surgical site
to
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discourage seroma formation, increase the rate of integration of the ADM graft
with the body, and provide a reliable, repeatable solution the surgeon may use
"off
the shelf' rather than utilizing valuable time and resources for graft
processing in
preparation for or during the surgical procedure.
[0034] Turning to exemplary embodiments, FIGS. 1A-1B illustrate
respective
front-plan and perspective views of one embodiment of a pre-shaped, meshed
ADM graft 100 derived from decellularized, full-thickness skin. Using full-
thickness
skin as the source for the ADM graft 100 ensures that the ADM graft 100 has
sufficient biomechanical properties to support varying surgical requirements,
including, for example, a suitable ultimate tensile strength, suture pull-out
resistance, and a Young's modulus indicative of a soft and supple graft.
[0035] In this embodiment, the pre-shaped, meshed ADM graft 100
may have
a pre-formed shape approximating a circle with a portion of the top removed
(i.e.,
slightly larger than a semi-circle). In one embodiment, as detailed in FIGS.
1A-1B,
the pre-shaped ADM graft may form a generally semi-circular tissue portion 102
having a radius, r, of 9 cm. The semi-circular tissue portion 102 may
approximate
a circle having a top portion of the circle removed in a straight line
disposed
perpendicular to the radius, r, of the circle. The tissue portion 102 may have
a
total height, h, of 10 cm, and a material thickness, t, of 1.0-2.0 mm.
Additional pre-
shaped ADM graft embodiments may feature various circular or elliptical shapes
with diameters ranging from 10 cm to 22 cm. The circular or elliptical tissue
portion of the ADM graft may feature a removed top portion, as shown in FIGS.
1A-1B, or an in-tact top portion, as necessary or desired for the intended
surgical
preparation.
[0036] In addition, the pre-shaped, meshed ADM graft 100 may
include a notch
104 to indicate which surface provides a basement membrane surface 106, or the
dermal surface to be implanted towards the patient's vascular bed. In one
embodiment, as shown in FIGS. 1A-1B, the notch 104 of the graft 100 may be
disposed in the top left corner to indicate the basement membrane surface 106.
In
other embodiments, the basement membrane may be removed.
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[0037] The decellularized, full-thickness dermal tissue may be
shaped and cut
into the pre-shaped ADM graft 100 using an appropriately designed scoring tool
along with a cutting tool such as, for example, a surgical scalpel or a
surgical
scissor. FIGS. 2A-2B illustrate respective front and rear perspective views of
one
embodiment of a scoring tool 130 featuring a semi-circular edge pattern 132
that
incorporates a raised notch 134 configured to form the indicator notch 104 in
the
pre-shaped ADM graft 100. To manufacture the pre-shaped ADM graft 100, an
embodiment of the scoring tool 130 may be placed upon a portion of full-
thickness
dermal tissue and used to "stamp" out the notched, semi-circular tissue
portion
102 from a larger ADM tissue portion. The cutting tool (not shown) may be used
to
trim excess tissue from around a perimeter of the scoring tool 130.
[0038] The pre-shaped nature of the ADM graft 100 disclosed
herein saves the
surgeon valuable time during a surgical procedure because there is no (or
minimal) need for the surgeon to shape, cut, or otherwise form the ADM graft
into
a desired shape during surgical preparation. Instead, the surgeon may simply
select an appropriately pre-shaped ADM graft for the particular surgery and
proceed.
[0039] Embodiments of the pre-shaped ADM graft 100 may
additionally include
a mesh or fenestration pattern to allow for increased fluid flow through the
graft
100, thereby reducing the chances of post-surgical seroma formation, a
frequent
complication after surgeries using existing ADM grafts. Pre-meshing also
prevents
the surgeon from having to perform any type or kind of meshing procedures
during surgical preparation or during a surgical procedure and ensures an
optimal
mesh ratio to provide maximum fluid egress, or drainage, from the surgical
site to
prevent seroma formation and a maximum graft surface area for improved
integration into the body post procedure.
[0040] FIGS. 3A-3B illustrate respective front views of an
exemplary mesh, or
fenestration, pattern 108 applied to the pre-shaped, meshed ADM graft 100,
shown in an open position, A, in which the mesh pattern appears as a series of
holes 110 (FIG. 3A) and in a resting position, B, in which the mesh pattern
108
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appears as a series of straight slits or lines 112 (FIG. 3B). In this
embodiment, the
mesh pattern 108 may feature a 1:1 graft:space ratio in which each mesh hole
110/line 112 has a length, L, of 1.5 nun, an end-to-end offset, Eo, of 1.5 mm,
and
a lateral offset, Lo, of 1 mm. Alternative embodiments may feature a different
mesh ratio and/or any appropriate and/or desired material and line dimensions.
For example, in one embodiment the mesh pattern 108 may feature a 2:1
graft:space ratio, with a material thickness of 0.8-2.5 mm.
[0041] The mesh or fenestration pattern 108 may be formed in the
pre-shaped,
meshed ADM graft 100 using a standard "skin mesher" 140 such as, for example,
a 4MED (or Rosenberg) Skin Graft Mesher (Distributed by Exsurco Medical,
Wakeman, Ohio). As shown in FIG. 4, a portion of decellularized, full-
thickness
dermal tissue 101 or, alternatively, a pre-shaped semi-circular tissue portion
102
may be inserted into the skin mesher 140, which has been adjusted to the
appropriate mesh or fenestration settings, for application of the mesh pattern
108
to the tissue 101.
[0042] A fluid egress study was completed to exhibit the
increased fluid egress,
or drainage, properties of the pre-shaped, meshed ADM graft 100. In the study,
the fluid drainage properties of the pre-shaped, meshed ADM graft 100 were
compared to those of a prior art first perforated ADM graft 142, shown in FIG.
5,
having a first perforation density pattern 144 of 41 perforations per 320 cm2,
or
approximately .128 perforations per cm2, and a prior art second perforated ADM
graft 146, shown in FIG. 6, having a second perforation density pattern 148 of
80
perforations per 320 cm2, or approximately .25 perforations per cm2 and
approximately twice that of the first perforation density pattern 144. Three
samples
of each were tested, each sample having a thickness between 0.9-2.0 mm.
[0043] FIGS. 7A-7B illustrate perspective views of a fluid
egress testing device
150 in first and second stages of egress testing, respectively. Upon release
of a
valve 151, a fluid 152 was passed from a fluid column 158, through the
respective
tested ADM graft (i.e., the pre-shaped meshed ADM graft 100, the first
perforated
ADM graft 142, or the second perforated ADM graft 144) stretched across the
fluid
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column 158 (not shown) and into a waste container 157. An egress or drainage-
time measurement was taken of the time required for a top surface 159 the
fluid
152 to fall 8.5 inches from a first fluid-level line 154 to a second fluid-
level line 156
along the fluid column 158 of the fluid egress testing device 150, as shown in
FIGS. 7A-7B, respectively. The drainage time for the fluid surface 159 to pass
from the first line 154 to the second line 156 was measured in triplicate for
each of
the pre-shaped meshed ADM graft 100, the first perforated ADM graft 142, and
the second perforated ADM graft 146. The drainage time measurements are
provided in the table of FIGS. 8A-83. As summarized in the chart of FIG. 9,
the
fluid egress study showed that the pre-shaped, meshed ADM graft 100 having the
1:1 graft:space ratio demonstrated significantly improved fluid egress
properties,
namely approximately 3x and 5x faster fluid egress as compared to the first
and
the second perforation density patterns 144, 148 of the first and the second
perforated grafts 142, 146, respectively.
[0044]
As discussed above, the mesh pattern 108 also increases the surface
area of the pre-shaped, meshed ADM graft 100, which, in turn, abets a rate of
integration of the graft 100 during the healing process after surgical
intervention.
The surface area calculations below compare the pre-shaped, meshed ADM graft
100 with the first and the second perforated grafts 142, 146 having the first
and
the second perforation patterns 144, 148, respectively, discussed above in
relation to FIGS. 5-6. In summary, the surface area of a 2x2 cm2 meshed ADM
graft having a 1 mm thickness and 130, 1.5 mm long mesh lines provides a 97.5%
increase in surface area over a 2x2 cm2 solid, non-meshed ADM graft, as shown
below:
Surf ace Area = (area of top of graft) + (44mesh lines)(perimeter of mesh
hole)(thickness)
Surface Area = (4 cm) + (130)(2 * 1.5 mm)(1 mm)
Surf aceArea = 4cm +3.9cm =7.9cm
Orignal Solid Graft Area= (2 cm)(2 cm) = 4 cm2
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7.9-4
Increase in Surface Area from Meshing = __________________ 4 * 100% = 97. 5%
[0045] The first perforated graft 142 having a 16 cm x 20 cm
perimeter and a 1
mm thickness, with a perforation density pattern 144 of 41 perforations per a
320
cm2 area, each perforation having a .15 cm radius, provides only a .3% surface-
area increase over a 16 cm x 20 cm solid, non-meshed ADM graft, as shown
below:
Sur face Area = (area of top of graft) + (# holes)(surface area of inside of
hale)
Surface Area= (320 cm2 - (41) (n- *152)) + (41)12* it *.15 cm)(.1 cm)
Sur face Area = 317.10188 cm2 + 3.86384 cm2 = 320.966 cm2
Orignal Solid Graft Area = (16 cm)(20 cm) = 320 cm2
320.966 - 320
Increase in Surface Area from Perforating = _________________________ * 320
100% = O. 3%
[0046] The second perforated graft 146 having a 16 cm x 20 cm
perimeter and
a 1 mm thickness, with a perforation density pattern 148 of 80 perforations
per a
320 cm2 area, each perforation having a .15 cm radius, provides only a .59%
surface-area increase over a 16 cm x 20 cm solid, non-meshed ADM graft, as
shown below:
Sur face Area = (area of top of graft) + (# holes)(surface area of inside of
hole)
Surface Area = (320 cm2 - (80) (n- *152)) + (80) (2* TE *.15 cm)(1 cm)
Surface Area = 314.34513 cm2 + 7.5392 cm2 = 321.884 cm2
Orignal Solid Graft Area = (16 cm)(20 cm) = 320 cm
321.884 -320
Increase in Sur f ace Area from Per f orating = ____________________ * 320
100% = 0.59%
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[0047] Thus, the fenestration pattern 108 applied to the pre-
shaped, meshed
ADM graft 100 significantly increases the exposed surface area of the graft
over
both existing solid and perforated grafts. This increase causes the pre-
shaped,
meshed ADM graft 100 to integrate into the human body much more rapidly
during the healing process after surgical intervention.
[0048] In one embodiment, the pre-shaped, meshed ADM graft 100
may be
formed of the ADM derived from full-thickness skin, as discussed above,
combined with antimicrobial elements that mitigate or prevent complications
arising from post-surgical infections. Antimicrobial agents compatible with
the
ADM may include, for example, silver in its colloidal, elemental, or ionic
form. The
silver may be complexed with chelating agents or may be added directly to the
ADM prior to final packaging. Similarly, other antimicrobial agents may be
combined with the ADM. Other agents known to be used medically may include
chlorhexidine glucon ate and antimicrobial peptides having various amino acid
chain lengths.
[0049] In one embodiment shown in FIG. 10, two pre-shaped,
meshed ADM
grafts 100 may be sutured together to form an ADM graft pocket 160. In this
embodiment, the two pre-shaped, meshed ADM grafts 100 may be sutured
together around the curved portions each of the semi-circular tissue portions
102,
such that a breast implant 162 may be disposed within the ADM graft pocket 160
between the two pre-shaped, meshed ADM grafts 100. The implant 162 is thus
supported from the bottom, without the need to be covered at the top. In one
embodiment, the ADM graft pocket 160 may be pre-sutured and then packaged
and stored for later surgical use, as discussed below in relation to FIGS. 11-
12, or
the ADM graft pocket may be formed from two pre-shaped, meshed ADM grafts
100 and sutured by the surgeon prior to or during a surgical procedure. In
another
operative embodiment applicable to reconstructive surgery, the implant may be
wrapped in the pre-shaped, meshed ADM graft 100 from an anterior side, and the
graft 100 sutured to the chest wall.
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[0050] After manufacture and to provide complete a shelf-stable,
packaged
ADM graft product 170, the pre-shaped, meshed ADM graft 100 (or the ADM graft
pocket 160) may be packaged along with two opposing pieces of backing material
172 and sterile water in a sealed medical sterilization pouch 174 such as, for
example, a Kapak pouch (manufactured by AMPAK Technology Inc. of
Larchmont, NY), as shown in FIG. 11, or further into a sealed, peelable
medical
sterilization pouch 176 known as a "peel pouch" or a "chevron pouch," as shown
in FIG. 12. The packaged ADM graft product 170 may then be irradiated to a
sterility assurance level (SAL) of 10-6 such that it may be stored at room
temperature for up to two years. The packaged ADM graft product 170 may be
labeled in any appropriate manner and may include information pertaining to
the
raw material, the shape, a use by date, special requirements, results of a
visual
inspection, and so on.
[0051] FIG. 13 provides a flowchart depicting an exemplary
method (200) of
manufacturing an embodiment of the pre-shaped, meshed ADM graft 100, the
ADM graft pocket 160, and the packaged ADM graft product 170, discussed
above. In this embodiment, the method may initiate with providing a portion of
full-
thickness donor-derived skin (202). Next, the epidermis layer and the fat
layer
adjacent to the dermis may be removed (204), and the dermal tissue may be
decellularized according to a well-known or a proprietary decellularization
process, resulting in the Acellular Dermal Matrix (ADM) (206). The ADM may
then
be shaped and/or cut into a pre-defined shape, such as the semi-circular
tissue
portion 102 or another appropriate shape, as necessary for an associated or
pre-
determined/assigned surgical procedure (208). The shaping may be accomplished
using any appropriate scoring tool 130 or another appropriate shaping tool,
and
the graft may be cut out with the cutting tool.
[0052] The ADM may also be meshed/fenestrated in the desired
mesh pattern
(e.g., 1:1 graft:space ratio, 2:1 graft:space ratio) using any appropriate
skin
mesher 140 (210). The meshing or fenestrating process (210) may occur before
or after the ADM is shaped into the pre-defined shape. The resulting pre-
shaped,
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meshed ADM graft 100 may then be verified for its thickness to specification
(e.g.,
1 mm ¨ 2 mm) (212) using a thickness gauge, and one or more antimicrobial
agents may be added to the pre-shaped, meshed ADM graft 100 to aid in post-
surgical infection prevention (213). The graft 100 may then be packaged (214)
between opposing pieces of backing material 172 within sterile water inside a
self-
sealing medical sterilization pouch 174 and/or a peelable pouch 176 such as,
for
example, a Kapak peel-pouch, forming the pre-shaped, meshed ADM graft
product 170. The packaged ADM graft product 170 may be irradiated to SAL 10-6
(216). After irradiation (216), the packaged, pre-shaped, meshed ADM graft
product 170 may be stored up to two years (218) before it is used in a
surgical
procedure (220).
[0053] In one embodiment, prior to packaging (214), two of the
pre-shaped,
meshed ADM grafts 100 may be joined (e.g., sutured) together about a curving
portion of each individual graft 100 to form the ADM graft pocket 160 (222),
discussed above in relation to FIG. 10. Alternatively, the ADM graft pocket
160
may be formed prior to a surgical procedure, within or prior to entering the
operating theater.
[0054] The method of manufacturing the packaged, pre-shaped, meshed ADM
graft product 170 provides a repeatable process for manufacturing the pre-
shaped, meshed ADM graft 100 formed from full-thickness donor-derived skin
such that surgeons may rely on the time-saving graft product in reconstructive
surgical procedures to provide a graft solution that has the robust physical
properties required of surgical skin grafts (as opposed to burn skin grafts),
promotes healing in the form of effective drainage from the surgical site, and
promotes integration of the graft into the patient's body.
[0055] In another embodiment, there may be provided a domed
shaped ADM
graft product 300 (see, for example FIGS. 14 and 16). FIGS. 15A and 15B
illustrate an embodiment of a shaping and scoring tool 400 for manufacturing
of
the domed shaped ADM graft product 300 as illustrated FIGURE 15. The shaping
and scoring tool 400 of FIG. 15, or a similar type of device or devices, may
be
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provided with a shaping portion 405 to impart the dome shape 305 to the ADM
graft product 300. Furthermore, a scoring portion 410 integrated in the same
device 305, or provided separately, is configured to impart a desired mesh
pattern
310 (which may be a concentric pattern formed on edges 315 of the ADM graft
product 300, or another desired mesh pattern, in addition to mesh patten 320,
across an entire surface of the ADM graft 300, or the domed shaped ADM graft
300may be shaped without a mesh pattern in a specific region or without any
mesh pattern across the entire ADM graft 300.)
[0056] With reference to FIG. 16, there is shown another
embodiment 500 of
an initial portion 325 of a domed shaped ADM graft product 300 having a multi-
notched peripheral edge 505. This multi-notched embodiment 500 may be one or
both of shaped and/or scored using the shaping and scoring tool 400 of FIG. 15
or
other suitable apparatus and processing steps.
[0057] The decellularized, full-thickness dermal tissue 500 may
be shaped and
cut into the domed shaped ADM graft 300 using an appropriately designed
scoring tool along with a cutting tool such as, for example, a surgical
scalpel or a
surgical scissor.
[0058] The pre-shaped nature of the domed shaped ADM graft
disclosed
herein saves the surgeon valuable time during a surgical procedure because
there
is no (or minimal) need for the surgeon to shape, cut, or otherwise form the
ADM
graft into a desired shape during surgical preparation. Instead, the surgeon
may
simply select an appropriately pre-shaped ADM graft for the particular surgery
and
proceed.
[0059] Embodiments of domed shaped ADM graft may additionally
include a
mesh or fenestration pattern to allow for increased fluid flow through the
graft,
thereby reducing the chances of post-surgical seroma formation, a frequent
complication after surgeries using existing ADM grafts. Pre-meshing also
prevents
the surgeon from having to perform any type or kind of meshing procedures
during surgical preparation or during a surgical procedure and ensures an
optimal
mesh ratio to provide maximum fluid egress, or drainage, from the surgical
site to
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prevent seroma formation and a maximum graft surface area for improved
integration into the body post procedure.
[0060] Although the above embodiments have been described in
language that
is specific to certain structures, elements, compositions, and methodological
steps, it is to be understood that the technology defined in the appended
claims is
not necessarily limited to the specific structures, elements, compositions
and/or
steps described. Rather, the specific aspects and steps are described as forms
of
implementing the claimed technology. Since many embodiments of the
technology can be practiced without departing from the spirit and scope of the
invention, the invention resides in the claims hereinafter appended.
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