Patent Description:
Tissue expanders are devices that are implanted beneath the skin or muscle and then gradually inflated to stretch the overlying tissue. Expanders are commonly used to either create a pocket for receiving a permanent prosthesis, or to generate an increased skin surface area in anticipation of the new skin being utilized for grafting or reconstruction.

Tissue expanders are typically formed of a silicone polymer shell. After implantation, a fluid, such as saline, is periodically injected into the tissue expander to enlarge it over time. Between injections, the surrounding skin is permitted to stretch and grow to create the increased skin surface and the increased tissue pocket for receipt of a permanent implant. Typically, a tissue expander has an injection element through which fluid can be introduced into or withdrawn from the expander. One such injection element is an integrated port having a septum that can be pierced with a hypodermic needle for the introduction into or withdrawal of fluid from the expander. Alternatively, the injection element may be a self-sealing area on the tissue expander which allows penetration by a hypodermic needle and self-closing after the needle has been withdrawn from the expander.

Conventional, commercially available tissue expanders have a single port that is used for inflating and deflating the shell of the tissue expander. They have no means for draining fluid (e.g., seroma) that forms around the outside of the shell of the tissue expander after implantation.

After surgery, patients typically have surgical drains placed to prevent blood and lymphatic fluid from building up under the skin, allowing for a quicker recovery. Some patients are sent home with drains that are implanted and connected to an external reservoir. Emptying these reservoirs can be traumatic because the patients have to measure and empty the reservoirs periodically (e.g., every morning). Many patients loathe surgical drains and look forward to having the drains removed.

In view of the above-noted problems, there is a need for tissue expanders having a single injection port that may be used for both inflating and deflating the tissue expander and draining fluid that collects around the tissue expander following surgery. There is also a need for tissue expanders having a single injection port that may be used for inflation/deflation, draining fluid and infusing fluid (e.g., an antibiotic solution) around the outside of an implanted tissue expander. Moreover, there remains a need for tissue expanders that remove seroma fluid without the need for a drain being attached <NUM> hours a day to a patient.

<CIT> describes a breast implant which includes an implant shell having an outer surface and defining a first fluid reservoir, and a porous membrane overlying the outer surface of the implant shell and defining a second fluid reservoir. The breast implant includes a filling tube having a first conduit in communication with the first reservoir and a second conduit in communication with the second reservoir. The breast implant includes an injection dome coupled with the filling tube and having a first fluid chamber in communication with the first conduit and a second fluid chamber in communication with the second conduit. The injection dome includes an upper end having an injection cover, a lower end including a support base, the first fluid chamber located adjacent the injection cover, the second fluid chamber located adjacent the support base, and a diaphragm dividing the first and second fluid chambers from one another. <CIT> describes a self-sealing patch for use with a tissue expander implant. The self-sealing patch serves as protection for the tissue expander against a hypodermic needle inadvertently missing a fluid injection port thereof by sealing a puncture through the patch. The patch includes a first sheet having a first sheet perimeter, a second sheet having a second sheet perimeter attached to the first sheet perimeter to form a pocket between the first sheet and the second sheet. Material is disposed within the pocket, where the material is hydrophobic material having a viscosity high enough that the material is prevented from flowing outside the pocket when either the first or second sheet is punctured with a hypodermic needle but low enough that the material flows to close a track made by a hypodermic needle puncturing the first or second sheet.

In one embodiment of the disclosure, a tissue expander preferably has a single injection port that may be used for inflating and deflating the tissue expander and draining fluid that forms around the outside of the tissue expander after implantation. Having a single injection port allows the empty tissue expander to be more easily folded and have a lower profile, which reduces the incision size needed for implantation. In addition, having a single injection port desirably reduces the total metal content of the tissue expander, which helps with MRI visualization and patient radiation. In addition, having only one injection port (with less metal than found in tissue expanders having two injection ports) will reduce the overall weight of the tissue expander.

In one embodiment, the injection port desirably includes a needle guard having a needle guard base and a needle guard rim that projects upwardly from the needle guard base. In one embodiment, the needle guard may be made of metal. In one embodiment, the needle guard may be made of polymer materials such as plastic. The injection port preferably includes a barrier membrane that is positioned in the needle guard. The barrier membrane divides the injection port into two distinct chambers, an inflation chamber in fluid communication with one or more inflation/deflation ports that are used for inflating and deflating the tissue expander, and a drainage chamber in fluid communication with one or more drainage ports that are used for draining fluid that collects outside the tissue expander.

In one embodiment, the shape, size and configuration of the barrier membrane of the injection port creates a space without occluding the inflation/deflation ports of the tissue barrier. The drainage chamber is coupled with the drainage ports and at least one drainage conduit (e.g., tubing) that connects to at least one drainage hole formed in the outer shell of the tissue expander. In one embodiment, the drainage conduit desirably includes a one-way check valve (e.g., a duck bill valve). In one embodiment, the one-way check valve allows fluid (e.g., seroma) to be drawn from the tissue surrounding the tissue expander without the possibility of inadvertently delivering saline into the patient.

In one embodiment, a first, conventional injection needle may be used for inflating and deflating the tissue expander with a fluid (e.g., a saline solution). In one embodiment, the first needle is the standard, injection needle that is used for inflation and deflation of the tissue expander. In one embodiment, the first needle may be used for injecting a solution (e.g., saline solution) into an outer shell to expand the size of the tissue expander. The first needle may also be used for removing the solution from the outer shell for reducing the size of the tissue expander.

In one embodiment, a second, specially designed needle, referred to as a drainage needle, may be used for draining fluid (e.g., seroma) that collects around the outer shell of the tissue expander following implantation. In one embodiment, the second drainage needle is used for drainage purposes only. The drainage needle desirably includes a hollow, cylindrical shaft made of medical grade material (e.g., stainless steel). In one embodiment, the distal end of the hollow, cylindrical shaft is closed and has a sharpened tip. The drainage needle preferably includes a side port formed in the side of the hollow needle shaft that is proximally spaced from the sharpened tip. The side port desirably enables fluid such as seroma fluid to be drawn into the drainage needle. The distance between the side port opening and the sharpened distal tip preferably positions the side port in communication with a drainage chamber as described in more detail herein.

In one embodiment, a tissue expander preferably includes integrated drainage and infusion systems. In one embodiment, the tissue expander desirably has a single injection port that may be used for inflating and deflating the tissue expander, for draining fluid that builds up around the tissue expander following surgery and implantation, and for delivering fluids around the outside of the shell following implantation.

In one embodiment, a tissue expander having an integrated drain preferably includes a shell having an opening and one or more drainage holes, and an injection port disposed in the opening of the shell and forming a fluid-tight seal with the shell, the injection port including a needle barrier having a needle barrier base with a top surface. In one embodiment, the injection port preferably includes a moveable barrier membrane overlying the top surface of the needle barrier base. In one embodiment, the moveable barrier membrane is moveable between a first position for inflating and deflating the shell with a first fluid and a second position for draining a second fluid from outside the shell.

In one embodiment, a magnet is coupled with the moveable barrier membrane. In one embodiment, a compressible spring is connected with the magnet. In one embodiment, the compressible spring is compressed for storing energy as the moveable barrier membrane moves from the first position to the second position. The energy may be released for returning the membrane to the first position.

In one embodiment, a needle may overlie the injection port and a second magnet may be coupled with the needle. In one embodiment, the second magnet repels the first magnet that is coupled with the moveable barrier for moving the moveable barrier from the first position to the second position.

In one embodiment, the tissue expander preferably includes an inflation port for inflating the shell with the first fluid, and a drainage port for draining the second fluid from outside the shell. In one embodiment, the inflation port is open and the drainage port is closed when the moveable barrier membrane is in the first position. In one embodiment, the inflation port is closed and the drainage port is open when the moveable barrier membrane is in the second position.

In one embodiment, a tissue expander preferably includes an injection port having a moveable barrier membrane that divides the injection port into an inflation chamber for inflating and deflating the tissue expander, and a drainage chamber for removing fluid that tends to collect around implants following surgery. In one embodiment, the moveable barrier membrane is connected to a magnet that, in turn, is coupled with a compressible spring. The barrier membrane is moveable between a first extended position in which the connected spring is extended, and a second retracted position in which the spring is compressed for storing energy in the spring.

In one embodiment, a first syringe with a needle is used for inflating and deflating the tissue expander. In one embodiment, a second syringe with a second needle contains a reversed pole magnet to repel the magnet coupled with the moveable membrane to occlude various openings. In the extended position, the moveable barrier membrane occludes a drainage port, with the compression spring keeping the moveable barrier membrane in place (i.e., in the extended position). With the barrier membrane in the extended position, saline injection for inflation and deflation is accomplished. A magnet mounted on the second syringe will repel the magnet coupled with the barrier membrane to push the movable barrier membrane down allowing drainage via syringe suction.

According to the invention, a tissue expander having an integrated drain includes a shell having an opening and one or more drainage holes, and an injection port disposed in the opening of the shell and forming a fluid-tight seal with the shell. The injection port may include a needle barrier having a needle barrier base with a top surface, and a barrier membrane overlying the top surface of the needle barrier base. The barrier membrane defines an inflation chamber located between the top surface of the needle guard base and a bottom surface of the barrier membrane, and a drainage chamber overlying a top surface of the barrier membrane. One or more inflation ports are in fluid communication with the inflation chamber for inflating and deflating the shell with a first fluid. A drainage conduit is in fluid communication with and extends between the drainage chamber and the one or more drainage holes for draining a second fluid from outside the shell.

In one embodiment, a first needle is used for inflating the shell and a second needle is used for draining fluid from around the outside of the shell. In one embodiment, the first needle has an opening at a pointed distal tip. In one embodiment, the first needle is adapted for insertion into the injection port so that the opening at the pointed distal tip is aligned with the inflation chamber for selectively inflating and deflating the shell using the first fluid. In one embodiment, the second needle has a closed distal tip and a side port spaced proximally from the closed distal tip. The second needle is adapted from insertion into the injection port so that the side port of the second needle is aligned with the drainage chamber for draining the second fluid from outside the shell.

In one embodiment, a tissue expander may include an infusion chamber overlying the top surface of the barrier membrane and separated from the drainage chamber, and an infusion conduit in fluid communication with and extending between the infusion chamber and at least one of the drainage holes for delivering an infusion fluid to the outside the shell.

In one embodiment, the tissue expander includes a needle assembly that is adapted for insertion into the injection port assembly. In one embodiment, the needle assembly has a first configuration in which an inflation lumen of the needle assembly is in fluid communication with the inflation chamber for selectively inflating and deflating the shell using the first fluid and a second configuration in which a drainage lumen of the needle assembly is in fluid communication with the drainage chamber for draining the second fluid from outside the shell.

In one embodiment, the needle assembly preferably includes a needle having an elongated shaft with a proximal end and a distal end. In one embodiment, the needle desirably includes the inflation lumen located at the distal end of the elongated shaft that is aligned with the inflation chamber and the drainage lumen that is proximal to the inflation lumen that is aligned with the drainage chamber, whereby the barrier membrane isolates the inflation lumen from the drainage lumen.

In one embodiment, the needle assembly includes an insert disposed inside the elongated shaft of the needle, which is moveable between an extended position in which the inflation lumen is open and the drainage lumen is closed, and a retracted position in which the inflation lumen is closed and the drainage lumen is open.

In one embodiment, the insert of the needle assembly preferably includes an elongated shaft having a proximal end that is open, a distal end that is closed by a distal end wall, and an elongated conduit that extends from the proximal end to the distal end of the insert. In one embodiment, the insert preferably has a side port formed in an outer wall of the elongated shaft of the insert that is in communication with the elongated conduit of the insert. In one embodiment, the side port of the insert is in alignment with the inflation lumen of the needle when the insert is in the extended position and the side port of the insert is in alignment with the drainage lumen of the needle when the insert is in the retracted position.

In one embodiment, the needle guard desirable has a needle guard rim that extends upwardly from the needle guard base.

In one embodiment, a barrier membrane support projects from the top surface of the needle guard base and toward the bottom surface of the barrier membrane for supporting an underside of the barrier membrane.

In one embodiment, the injection port assembly preferably includes an injection dome secured to an upper end of the needle guard rim. In one embodiment, the injection dome desirably includes a base having a bottom surface with an annular groove formed therein, whereby the upper end of the needle guard rim is disposed within the annular groove of the injection dome for securing the injection dome to the needle guard.

In one embodiment, the needle guard rim has a first height, and the injection dome has a second height that is less than the first height of the needle guard rim.

In one embodiment, the needle guard rim has one or more assembly openings formed therein that are located adjacent the upper end of the needle guard rim. In one embodiment, the one or more assembly openings are disposed within the annular groove of the injection dome.

In one embodiment, a drainage port passes through the needle guard rim for interconnecting the drainage chamber and the drainage conduit. In one embodiment, the drainage port is located between the bottom surface of the base of the injection dome and the needle guard base.

In one embodiment, silicone material (e.g., uncured silicone), such as silicone sheeting, preferably overlies the upper end of the needle guard rim and is in contact with the one or more assembly openings formed in the needle guard rim for securing the injection dome to the upper end of the needle guard rim.

In one embodiment, the drainage chamber is located between the bottom surface of the injection dome and the top surface of the barrier membrane.

In one embodiment, the one or more inflation ports pass through lateral openings provided in the needle guard rim. In one embodiment, the one or more inflation ports are located between the drainage port and a top surface of the needle guard base.

In accordance with the invention, the drainage conduit has a second end that is coupled with a drain, which, in turn, is in fluid communication with the one or more drainage holes that are formed in the shell.

In accordance with the invention, the tissue expander includes a drainage manifold that is aligned with and covers the one or more drainage holes formed in the shell.

In one embodiment, the drainage manifold includes a drainage manifold port. In one embodiment, the second end of the drainage conduit may be secured to the drainage manifold port for connecting the drainage conduit to the drainage manifold.

In one embodiment, the drainage conduit preferably includes a one-way check valve that is configured to enable fluid passing through the drainage conduit to move in only one direction toward the drainage chamber of the injection port assembly.

In one embodiment, the drainage manifold has an inner face and an outer face. In one embodiment, the drainage manifold port projects from the inner face of the drainage manifold, and the outer face of the drainage manifold is secured to an inner surface of the shell to form a water-tight seal between the drainage manifold and the inner surface of the shell.

In one embodiment, the inner face of the drainage manifold surrounds a trough. In one embodiment, the tissue expander includes one or more drains that are disposed in the trough and that are aligned with the one of more drainage holes formed in the shell. In one embodiment, the drainage manifold port is in fluid communication with the trough and the one or more drains that are disposed within the trough.

In one embodiment, a tissue expander may include a drainage manifold having an inner face and an outer face, the outer face of the drainage manifold forming a water-tight seal with the inner surface of the shell and surrounding the one or more drainage openings formed in the shell.

In one embodiment, an integral drain preferably includes a sealed drain cover that is secured with the inner face of the drainage manifold. In one embodiment, a second end of the drainage conduit is preferably coupled with the drainage manifold.

In one embodiment, a tissue expander may include an infusion chamber that overlies the top surface of the barrier membrane, whereby the barrier membrane separates the infusion chamber from the drainage chamber.

In one embodiment, an infusion conduit in fluid communication with and extends between the infusion chamber and at least one of the one or more drainage holes formed in the shell for delivering an infusion fluid to the outside the shell.

In one embodiment of the disclosure, a tissue expander having an integrated drain preferably includes a shell having an injection port opening and one or more drainage holes formed in the shell, and an injection port assembly disposed in the injection port opening for forming a fluid-tight seal with the shell, the injection port assembly including a needle guard having a needle guard base with a top surface.

In one embodiment, a barrier membrane is disposed within the needle guard and overlies the top surface of the needle guard base.

In one embodiment, the barrier membrane define an inflation chamber that is located between the top surface of the needle guard base and a bottom surface of the barrier membrane for inflating and deflating the shell with a first fluid.

In one embodiment, the barrier membrane defines a drainage chamber located within the needle guard that overlies a top surface of the barrier membrane for draining a second fluid from outside the shell through the one or more drainage holes.

In one embodiment, a needle assembly is preferably configured for insertion into the injection port assembly. In one embodiment, the needle assembly has a first configuration in which an inflation lumen of the needle assembly is in fluid communication with the inflation chamber for selectively inflating and deflating the shell using the first fluid and a second configuration in which a drainage lumen of the needle assembly is in fluid communication with the drainage chamber for draining the second fluid from outside the shell.

In one embodiment, a barrier membrane support projects from the top surface of the needle guard base toward the bottom surface of the barrier membrane for supporting an underside of the barrier membrane.

In one embodiment, the needle guard preferably includes a needle guard rim that extends upwardly from the needle guard base.

In one embodiment, the injection port assembly preferably includes an injection dome that is secured to an upper end of the needle guard rim. In one embodiment, the injection dome preferably includes a base having a bottom surface with an annular groove formed therein, whereby the upper end of the needle guard rim is disposed within the annular groove of the injection dome for securing the injection dome to the needle guard.

In one embodiment, the needle guard rim has one or more assembly openings (e.g., elongated slots) that are formed therein that are located adjacent the upper end of the needle guard rim.

In one embodiment, the one or more assembly openings are disposed within the annular groove of the injection dome.

In one embodiment, silicone material overlies the upper end of the needle guard rim and is in contact with the one or more assembly openings formed in the needle guard rim.

In one embodiment, the silicone material preferably secures the injection dome to the upper end of the needle guard rim.

Dip molding using an appropriately sized and shaped mandrel can be used to form the outer shell, although other suitable means such as injection molding or spraying may also be used. With dip molding, the mandrel is dipped into silicone dispersion and then removed to allow for partial cure and solvent evaporation. The process is generally repeated several times. Once the outer shell has been formed it is removed from the mandrel. The dip molding process results in the formation of a partial shell that has an opening, e.g., a circular hole (patch hole), on the posterior side. The injection port is installed and the patch hole is subsequently covered with a patch that seals the hole, thus forming a complete, fluid impervious shell. The patch may be attached to the partial shell using silicone rubber or other similar biocompatible adhesive. The completed shell can either be non-filled or partially prefilled. After implantation, the expander is intraoperatively filled through the injection port with saline, gel, foam, or combinations of these materials or other suitable materials known in the art to gradually expand the tissue expander to the desired dimensions. Filling through the injection port typically takes place over the course of multiple office visits.

These and other preferred embodiments of the present disclosure will be described in more detail below.

The embodiments illustrated by <FIG>, <FIG>, <FIG>, and <FIG> include all of the features required by the present invention. Other figures illustrate components of embodiments of the invention.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> preferably includes a shell <NUM> and an injection port <NUM> located at a top side of the shell. The shell <NUM> may have any desired shape and any thickness that is suitable for the purpose of the particular tissue expander. The shell <NUM> may be formed of a biocompatible elastomer material such as silicone.

In one embodiment, the tissue expander <NUM> preferably includes one or more stability tabs <NUM> that may be used for securing the tissue expander <NUM> to tissue. In one embodiment, sutures or surgical fasteners may be utilized for securing the one or more stability tabs <NUM> to a patient's tissue. In one embodiment, the tissue expander <NUM> desirably includes one or more drainage holes <NUM> that are provided on the shell <NUM>. The one or more drainage holes <NUM> may be used to drain fluid (e.g., seroma fluid) that may accumulate around the tissue expander <NUM> following surgical implantation.

Referring to <FIG> and <FIG>, in one embodiment, the injection port <NUM> may be secured to an opening that is present in the shell for sealing the shell <NUM>. In one embodiment, the injection port <NUM> is fitted into the opening in the shell <NUM> at a location that faces toward a patient's skin surface. The injection port may be formed of an elastomeric material. In one embodiment, the injection port <NUM> desirably includes a septum region <NUM> that is preferably located at the central region of the upper surface of the injection port <NUM> and/or the tissue expander <NUM>. The septum region <NUM> is desirably self-sealing for preventing the leaking of fluid from the tissue expander <NUM> after an injection needle is removed from the injection port <NUM>.

In one embodiment, the injection port <NUM> desirably includes an outer flange <NUM> that overhangs the outer surface of the shell <NUM>. In one embodiment, the injection port <NUM> desirably includes a self-sealing, safety patch <NUM> that is secured to the inner surface of the shell <NUM>, whereby the shell is at least partially sandwiched between the flange <NUM> of the injection port and the self-sealing, safety patch <NUM>. The self-sealing, safety patch preferably has a diameter that is larger than the flange <NUM> of the injection port <NUM> so that the safety patch extends beyond the outer perimeter of the flange <NUM>.

In one embodiment, an appropriately sized and shaped mandrel may be used to form the shell <NUM> of the tissue expander <NUM>. In one embodiment, the shell <NUM> may be formed using a dip molding methodology, although other methodologies may be used including spraying a mandrel with a shell forming solution or injection molding. During a dip molding method, a mandrel is dipped into silicone dispersion and then removed to allow for partial cure and solvent evaporation. The dipping step is repeated several times. Once the shell has been formed, it is removed from the mandrel. The dip molding process results in the formation of a partial shell that has an opening, e.g., a circular hole (patch hole). The injection port <NUM> and the safety patch <NUM> are installed, thus forming a complete, fluid impervious shell. The safety patch <NUM> may be attached to the inner surface of the shell <NUM> using silicone rubber or other similar biocompatible adhesives. The completed shell can be non-filled or partially pre-filled. After implantation, the tissue expander <NUM> is filled through the septum region <NUM> with saline, gel, foam, or combinations of these materials or other suitable materials known in the art to gradually expand the tissue expander <NUM> to the desired dimensions. This typically takes place over the course of multiple office visits.

In one embodiment, the injection port <NUM> desirably includes a needle guard <NUM> having needle guard base <NUM> and a needle guard rim <NUM> that extends upwardly from the needle guard base <NUM>. In one embodiment, the needle guard rim <NUM> completely surrounds the outer perimeter of the needle guard base <NUM>.

In one embodiment, the injection port <NUM> desirably includes a barrier membrane <NUM> that extends from one side of the needle guard rim <NUM> to an opposite side of the needle guard rim portion <NUM>. In one embodiment, the barrier membrane <NUM> preferably overlies the needle guard base <NUM> and is co-extensive with the area of the needle guard base <NUM>. The barrier member <NUM> preferably divides the injection port <NUM> into an inflation chamber <NUM> that is used to introduce an inflation solution into the shell <NUM> to expand the tissue expander and/or remove a solution from the shell to deflate the tissue expander, and a drainage chamber <NUM> that is used to drain fluid (e.g., seroma fluid) that may collect around the shell <NUM> of the tissue expander <NUM> following implantation.

In one embodiment, the inflation chamber <NUM> is in fluid communication with shell inflation ports 128A, 128B that pass through lateral openings provided in the needle guard rim <NUM>. In one embodiment, an injection needle may be used to introduce fluid (e.g., saline solution) into the inflation chamber <NUM> whereupon it flows through the inflation ports 128A, 128B for inflating the shell <NUM> with the solution. In one embodiment, an injection needle may be used to generate a vacuum within the inflation chamber with removing fluid from the shell <NUM> to deflate the tissue expander <NUM>.

In one embodiment, the drainage chamber <NUM> of the injection port <NUM> preferably includes a drainage port <NUM> that passes through an opening <NUM> formed in the needle guard rim <NUM> of the needle guard <NUM>. In turn, the drainage port <NUM> is connected to a first end <NUM> of a drainage conduit <NUM>. The drainage conduit <NUM> desirably has a second end <NUM> that is coupled with a drain <NUM>, which is in fluid communication with one or more drainage holes <NUM> formed in the shell <NUM>.

In one embodiment, a first needle <NUM> is utilized for inflating and deflating the shell <NUM> of the tissue expander <NUM>. The first needle <NUM> preferably has a pointed tip <NUM> and an opening <NUM> provided at the pointed tip <NUM>. In one embodiment, the pointed tip <NUM> of the first needle <NUM> is passed through the septum <NUM> and the barrier membrane <NUM> so that the opening <NUM> at the distal tip <NUM> of the first needle <NUM> is aligned with the inflation chamber <NUM> of the injection port <NUM>. Once the opening <NUM> of the first needle <NUM> is positioned within the inflation chamber <NUM>, a fluid (e.g., saline solution) may be passed through the needle opening <NUM> whereupon the injected fluid flows into the inflation chamber <NUM>, through lateral openings in the needle guard rim <NUM>, and through the inflation ports 128A, 128B for inflating the shell <NUM> with the injected fluid. In order to deflate the tissue expander <NUM>, the first needle <NUM> may be used to remove fluid from the shell by withdrawing fluid through the inflation ports 128A, 128B and into the inflation chamber <NUM>, whereupon the fluid may be removed from the shell <NUM> via the first needle <NUM>.

In one embodiment, a second needle <NUM> may be used to drain fluid that collects around the outer perimeter of the tissue expander <NUM>. In one embodiment, the second needle <NUM> has a pointed distal tip <NUM> and a side port <NUM> that is spaced proximally away from the pointed distal tip <NUM>. As will be described in more detail herein, the side port <NUM> of the second needle enables fluid that has collected around the outside of the shell to be drained and removed from a patient's body.

Referring to <FIG> and <FIG>, in one embodiment, the tissue expander <NUM> preferably includes a drainage manifold <NUM> that is aligned with and covers the one or more drainage holes <NUM> that are provided on the shell <NUM>. In one embodiment, the second end <NUM> of the drainage conduit <NUM> is secured to a drainage manifold port <NUM> for connecting the drainage conduit <NUM> to the drainage manifold <NUM>.

In one embodiment, the drainage conduit <NUM> desirably includes a one-way check valve <NUM> (<FIG>) that enables the fluid passing through the drainage conduit to move in only one direction designated DIR1, i.e., toward the drainage chamber <NUM> (<FIG>) of the injection port <NUM>.

Referring to <FIG>, in one embodiment, the drainage manifold <NUM> desirably includes the drainage manifold port <NUM> that projects from an inner face <NUM> of the drainage manifold <NUM>. In one embodiment, the drainage manifold <NUM> preferably has an outer face <NUM> that surrounds a trough <NUM>, which is adapted to receive one or more drains <NUM> (<FIG>) that are preferably aligned with the one or more drainage holes <NUM> (<FIG>) provided on the shell. The drainage manifold port <NUM> is desirably in fluid communication with the trough <NUM> provided at the front face <NUM> of the drainage manifold <NUM>. In one embodiment, the outer face <NUM> of the drainage manifold <NUM> is preferably secured to the inner surface of the shell <NUM> (<FIG>) to form a water-tight seal with the inner surface of the shell so as to divide the fluid that is used to inflate and deflate the shell from the fluid that is drained from outside the shell.

In one embodiment, one or more drains <NUM> (<FIG>) are desirably positioned within the trough <NUM> of the drainage manifold <NUM> for draining fluid from around the perimeter of the tissue expander. In one embodiment, the drains are desirably aligned with the drainage holes <NUM> (<FIG>) formed in the shell <NUM> of the tissue expander <NUM>.

Referring to <FIG>, in one embodiment, a drain <NUM> preferably has a core <NUM> with struts <NUM> that project from the core <NUM> along the longitudinal axis of the core. Each of the outer ends of the struts <NUM> have respective overhang portions <NUM> which extend longitudinally throughout the length of the struts <NUM>. As shown in <FIG>, in one embodiment, the overhang portions <NUM> are arcuate members that extend on either side of their respective struts <NUM>. The overhang portions <NUM> are sized to form a generally oval shaped member at the periphery of the drain <NUM>, with small gaps between the adjacent overhang portions <NUM>. Each of these gaps forms a longitudinal groove <NUM>, parallel to the longitudinal axis of the core <NUM>, and extending throughout the length of the drain <NUM>. The core portion <NUM>, the struts <NUM>, and the overhand portions <NUM> cooperate to form plural channels or lumens <NUM> that extend along the length of the drain <NUM>. The longitudinal grooves <NUM> permit fluid communication between the respective lumens <NUM> and a wound.

In one embodiment, the drain <NUM> may be similar to the surgical drains disclosed in <CIT>.

Referring to <FIG>, in one embodiment, in order to inflate the tissue expander <NUM>, the pointed distal tip <NUM> of the first needle <NUM> is passed through both the septum region <NUM> of the injection port <NUM> and the barrier membrane <NUM> until the opening <NUM> at the distal tip <NUM> of the inflation needle <NUM> is aligned with the inflation chamber <NUM> of the injection port. In one embodiment, a fluid (e.g., saline solution) is injected from the opening <NUM> at the distal tip <NUM> of the first needle <NUM> whereupon the injected fluid flows into the inflation chamber <NUM> and through the inflation ports 128A, 128B for inflating the shell <NUM> and expanding the tissue expander <NUM>. The distal tip <NUM> is desirably halted by the needle guard base <NUM> of the needle guard <NUM> for prevented the distal tip of the first needle from passing through the bottom of the injection port <NUM> and/or damaging the shell of the tissue expander. If the opening <NUM> at the distal tip <NUM> of the first needle <NUM> were improperly aligned with the drainage chamber <NUM> of the injection port <NUM> and fluid under pressure was injected from the opening <NUM> of the first needle <NUM>, the one-way check valve <NUM> (<FIG>) provided inside the drainage conduit <NUM> will prevent the fluid from passing through the drainage conduit and reaching the drain <NUM> located at the second end <NUM> of the drainage conduit <NUM>.

Referring to <FIG> and <FIG>, in one embodiment, bodily fluid that collect around the shell <NUM> of the tissue expander <NUM> may be drained from the one or more drainage openings <NUM> (<FIG>) provided on the shell <NUM>. In one embodiment, the second needle <NUM> (<FIG>) is utilized for draining the fluid that has accumulated around the outer perimeter of the shell <NUM>. In one embodiment, the pointed distal tip <NUM> of the second needle <NUM> is advanced through the barrier membrane <NUM> until the pointed tip <NUM> abuts against the top surface of the needle guard base <NUM> of the needle guard <NUM>. When the pointed distal tip <NUM> of the second needle <NUM> engages the needle guard base <NUM>, the side port <NUM> of the second needle <NUM> (which is spaced from the distal tip <NUM>) is preferably aligned with the drainage chamber <NUM> of the injection port <NUM> that overlies the top surface of the barrier membrane <NUM>. A vacuum may then be drawn through the second needle <NUM> for withdrawing fluid (e.g., seroma) through the drainage conduit <NUM>. The drainage conduit <NUM> preferably includes the one-way check valve <NUM> that enables the accumulated fluid to flow in only one direction (e.g., toward the injection port <NUM>). The drained fluid preferably passes through the one-way check valve <NUM>, through the drainage port <NUM>, and into the drainage chamber <NUM> where it is withdrawn through the side port <NUM> of the drainage needle <NUM>. <FIG> shows the flow of the drained fluid as it flows through the one-way check valve <NUM>, the first end <NUM> of the drainage conduit <NUM>, the drainage chamber <NUM>, and into the side port <NUM> of the second needle <NUM> for being removed from the shell <NUM> of the tissue expander <NUM>.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> has an integral drain provided therein for draining fluid and/or liquids that accumulate around the perimeter of the shell <NUM> of the tissue expander. In one embodiment, the tissue expander <NUM> preferably includes a drainage conduit <NUM> having a first end <NUM> that is coupled with a drainage port <NUM> of an injection port <NUM>, and a second end <NUM> that is coupled with a drainage manifold <NUM> that is positioned adjacent drainage openings <NUM> provided on the shell <NUM>. In one embodiment, the integral drain does not include a drain <NUM> (<FIG>) similar to that shown and described above in <FIG>. Rather, the integral drain includes a sealed drain cover <NUM> that is secured with an inner face <NUM> of the drainage manifold <NUM>. The outer face <NUM> of the drainage manifold <NUM> is preferably secured to an inner surface <NUM> of the shell <NUM> to form a water-tight seal between the inner surface of the shell and the outer face of the drainage manifold <NUM> for separating the inflation fluid that circulates inside the shell <NUM> from the liquid that accumulates around the shell <NUM> and that is drained through the one or more drainage holes <NUM>.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> preferably includes an outer shell <NUM>, an injection port <NUM>, stabilizing tabs <NUM>, and drainage and infusion holes <NUM> provided on the shell <NUM>. In one embodiment, the tissue expander <NUM> desirably includes a manifold <NUM> that is preferably used for both drainage and infusion and that is positioned inside the shell <NUM> adjacent the drainage and infusion holes <NUM>. In one embodiment, a drainage conduit 336A has a first end 334A coupled with a drainage and infusion chamber <NUM> of the injection port <NUM> and a second end 338A coupled with a drainage port 356A of the manifold <NUM>. As will be described in more detail herein, the drainage conduit 336A desirably includes a one-way check valve 358A that allows fluid that is drained through the holes <NUM> to flow from the second end 338A to the first end 334A of the drainage conduit 336A, but not in the opposite direction from the first end 334A to the second end 338A of the drainage conduit 336A.

In one embodiment, the tissue expander <NUM> desirably includes an infusion conduit 336B having a first end 334B coupled with the drainage and infusion chamber <NUM> of the injection port <NUM> and a second end 338B coupled with an infusion port 356B provided on the manifold <NUM>. In one embodiment, a solution (e.g., a medical solution, an antibiotic) may be passed through the infusion conduit 336B for being dispensed from the holes <NUM> formed in the shell <NUM>. In one embodiment, the infusion conduit 336B desirably includes a one-way check valve 358B that allows an infusion solution to flow from the first end 334B of the infusion conduit 336B to the second end 338B of the infusion conduit 336B, but not flow through the infusion conduit 336B in the opposite direction.

Referring to <FIG> and <FIG>, in one embodiment, the tissue expander <NUM> desirably includes the drainage conduit 336A having a one-way check valve 358A that allows the drained fluid to flow from the second end 338A to the first end 334A of the drainage conduit 336A in the direction designed DIR1, but not in the reverse direction designed DIR2. In one embodiment, the manifold <NUM> is secured to the second end 338A of the drainage conduit 336A. The drainage system desirably includes one of more drains <NUM> that are located within the trough <NUM> of the manifold <NUM> and that are located between the opening at the second end 338A of the drainage conduit 336A and the one or more holes <NUM> formed in the shell <NUM>. The fluid that is drained through the one or more holes <NUM> passes through the one or more drains <NUM> and into the drainage conduit 336A.

<FIG> shows the one-way check valve 358B provided in the infusion conduit 336B. The one-way check valve 358B enables the infusion fluid to flow in only one direction designed DIR2 from the first end 284B to the second end 288B of the infusion conduit 286B, but not in the opposite direction designated DIR1.

Referring to <FIG>, in one embodiment, an injection port <NUM> of a tissue expander <NUM> desirably includes a moveable barrier membrane <NUM> that is positioned inside a needle guard <NUM> having needle guard base <NUM> and a needle guard rim <NUM> that projects upwardly from the needle guard base <NUM>. The injection port <NUM> preferably includes a magnet <NUM> that is positioned atop a compressible spring <NUM> that normally urges the moveable barrier membrane <NUM> into an extended position shown in <FIG>. In one embodiment, the moveable barrier membrane <NUM> desirably includes a membrane rim <NUM> that blocks a drainage port <NUM> when the moveable barrier membrane <NUM> is in the extended position shown in <FIG>. In one embodiment, the magnet <NUM> and the movable barrier membrane <NUM> are connected together and move together between an extended position shown in <FIG> and a compressed position shown in <FIG>.

In one embodiment, in order to inflate a shell of a tissue expander with a solution, an inflation needle <NUM> having a distal tip <NUM> with an opening <NUM> is preferably passed through the dome <NUM> of the injection port <NUM> until the distal tip <NUM> of the needle <NUM> abuts against the top surface of the needle guard base <NUM> of the needle guard <NUM>. The compression spring <NUM> is extended so that the magnet <NUM> and the moveable barrier membrane <NUM> are in the extended position. When a solution is injected from the opening <NUM> at the distal tip <NUM> of the needle <NUM>, the injected solution desirably flows through openings <NUM> in a floor of the barrier membrane <NUM> and through an inflation port <NUM> for filling an outer shell of the tissue expander <NUM>.

Referring to <FIG>, in one embodiment, a second magnet <NUM> may be positioned over the elongated shaft of the injection needle <NUM>. The second magnet <NUM> may be positioned adjacent a lower end of a syringe. The second magnet <NUM> preferably generates a magnetic field that repels the first magnet <NUM> located inside the injection port <NUM> The repelling forces between the magnets <NUM>, <NUM> move the movable barrier membrane <NUM> into the compressed position shown in <FIG>, whereupon the barrier rim <NUM> of the barrier membrane <NUM> is positioned below an opening of a drainage port <NUM> so that fluid accumulating around the perimeter of the tissue expander may be withdrawn through the drainage port. <FIG> shows a phantom line P that indicates a possible insertion path for the needle <NUM> when the needle is inserted into the injection port <NUM>.

Referring to <FIG>, the second magnet <NUM> around the injection needle <NUM> repels the first magnet <NUM> within the injection port <NUM> for compressing the spring <NUM> and moving the movable barrier membrane <NUM> into the compressed position. The peripheral rim <NUM> of the moveable barrier membrane <NUM> no longer blocks the drainage port <NUM> so that drainage fluid may be drawn into the opening <NUM> at the pointed tip <NUM> of the injection needle <NUM>. As the moveable barrier membrane <NUM> moves into the lower, compressed position shown in <FIG>, the compression spring <NUM> coupled with an underside of the first magnet <NUM> is compressed. When the second magnet <NUM> is moved away from the injection port <NUM>, the energy stored in the compression spring <NUM> will return the movable barrier membrane <NUM> back to the extended position shown in <FIG>. When the movable barrier membrane <NUM> is returned to the extended position shown in <FIG>, the peripheral rim <NUM> of the movable barrier membrane <NUM> once again blocks the drainage port <NUM> of the injection port <NUM> of the tissue expander <NUM>.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> desirably includes an outer shell <NUM>, and an injection port <NUM>. The tissue expander <NUM> desirably includes a plurality of holes <NUM> that are formed in a top side of the outer shell <NUM>. The series of holes <NUM> may be utilized for draining fluid that accumulates around the outside of the shell <NUM> and/or or infusing a medical solution through the holes <NUM> and around the outside of the shell <NUM>. In one embodiment, the tissue expander <NUM> may include one or more drainage conduits and drains as disclosed herein. In one embodiment, the tissue expander <NUM> may include one or more infusion conduits as disclosed herein. In one embodiment, the tissue expander <NUM> may include a drainage conduit in communication with one or more of the holes <NUM> and an infusion conduit in communication with one or more of the holes <NUM>.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> desirably includes an outer shell <NUM>, and an injection port <NUM>. The tissue expander <NUM> desirably includes a series of radially extending holes <NUM> that may be used for draining fluid that has accumulated around the outside of the shell <NUM> and/or infusing fluid from the holes to flow around the outside of the shell <NUM>.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> preferably includes a shell <NUM> and an injection port <NUM> that is positioned in an opening of the shell <NUM>. In one embodiment, the shell <NUM> preferably has a drainage opening <NUM> formed therein, and a drainage conduit <NUM> that extends between the drainage opening <NUM> and the injection port <NUM>.

In one embodiment, the injection port <NUM> preferably includes an injection compartment <NUM>. A first one-way check valve 758A is positioned between a first end <NUM> of the drainage conduit <NUM> and the injection compartment <NUM>. Under vacuum, the first one-way check valve 758A opens for allowing fluid to be drawn into the injection compartment <NUM>, such as by using a needle <NUM>. Under pressure, the first one-way check valve 758A remains closed.

In one embodiment, the tissue expander <NUM> preferably includes a second one-way check valve 758B that enables inflation fluid (e.g., saline solution) to be introduced into the injection compartment <NUM> and flow past the second one-way check valve 758B into the interior of the outer shell <NUM> for inflating the tissue expander <NUM>. The second one-way check valve 758B opens under pressure and remains closed under vacuum. Thus, the first one-way check valve 758A opens under vacuum and the second one-way check valve 758B open under pressure so that the first and second one-way check valves 758A and 758B are not open at the same time. In one embodiment, the same syringe/needle <NUM> may be used for delivering an inflation fluid into the injection compartment <NUM> on a forward stroke and evacuating drainage fluid from the injection compartment <NUM> on a reverse stroke.

In one embodiment, the injection port <NUM> of the tissue expander <NUM> desirably includes a third one-way check valve 758C that is located between the injection compartment <NUM> and an interior region of the shell <NUM>. The third one-way check valve 758C is desirably opened under vacuum, but has a highly restricted aperture <NUM> so that under vacuum the third one-way check valve 758C will bleed some saline back into the injection compartment <NUM> for flushing the compartment and to also deflate the tissue expander <NUM>.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> desirably includes an outer shell <NUM> and an injection port <NUM>. The injection port <NUM> desirably includes a first injection chamber 855A that is in communication with first and second check valves 858A, 858B, and a second injection chamber 855B that is in communication with a third check valve 858C. A membrane <NUM> divides the first injection chamber 855A from the second injection chamber 855B. A distal end of an injection needle <NUM> may be passed through the membrane for accessing the second injection chamber 855B to inject a fluid into or remove a fluid from the second ejection chamber 855B.

In one embodiment, the first check valve 858A is coupled with a drainage conduit 836A in communication with a drainage opening 808A formed in the outer shell <NUM>. The second check valve 858B is desirably in communication with an infusion conduit 836B that is coupled with an infusion opening 808B formed in the outer shell <NUM> of the tissue expander <NUM>. The first one-way check valve 858A opens under vacuum in the first injection chamber 855A for draining fluid that has accumulated around the tissue expander through the drainage opening 808A and the drainage conduit 836A. The drained fluid may be removed from the first injection chamber 855A using a needle <NUM>. The second one-way check valve 858B opens under pressure in the first injection compartment 855A for passing infusion fluid through the infusion conduit 836B to the infusion opening 808B. Thus, in one embodiment, the same syringe <NUM> may be used to deliver a fluid (e.g., an antibiotic solution) on a forward stroke via the infusion conduit 836B and to evacuate drainage fluid (e.g., seroma) via the drainage conduit 836A and the drainage opening 808A on a reverse stroke.

In one embodiment, the third valve 858C is located in the second injection chamber 855B. The third valve 858C may be used for inflating and deflating the outer shell <NUM> of the tissue expander <NUM>. Under pressure, fluid in the second injection chamber 855B passes through the third valve 858C for inflating the outer shell <NUM>. Under vacuum, fluid in the outer shell <NUM> is drawn through the third valve 858C into the second injection chamber 855B where it may be withdrawn using the needle <NUM>.

Referring to <FIG>, in one embodiment, tissue expander <NUM> includes an outer shell <NUM> with an injection port <NUM>. The injection port desirably includes a first injection chamber 955A that is in communication with a drainage conduit 936A, and a second injection chamber 955B that is in communication with an infusion conduit 936B. In one embodiment, a first membrane 965A separates the first and second injection chambers 955A and 955B from one another. In one embodiment, the injection port <NUM> may include injection zone markers for locating and distinguishing between the first and second injection chambers 955A and 955B, as disclosed in commonly assigned <CIT> The injection zone makers may be made of a material having ultrasonically detectable markers incorporated therein. In one embodiment, the markers may include a plurality of microcavities that are located relative to the first and second injection chambers of the injection port so that, when ultrasonically detected, such detection includes the locations of the first and second injection chambers.

The tissue expander <NUM> desirably includes a first check valve 958A that is coupled with a first end of the drainage conduit 936A. The drainage conduit 936A, in turn, is coupled with a drainage hole 908A provided in the outer shell <NUM>. Under vacuum within the first injection chamber 955A, the first check valve 958A opens for allowing drainage fluid to be drawn through the drainage opening 908A, the drainage conduit 936A, and the first one-way check valve 958A, and into the first injection chamber 885A for being withdrawn from the first injection chamber using a needle <NUM>.

The second check valve 958B is provided at a first end of the infusion conduit 936B. The infusion conduit 936B has a second end that is coupled with an infusion hole 908B formed in the outer shell <NUM>. Under pressure within the second injection chamber 955B, the second one-way check valve 958B opens for allowing fluid injected into the second injection chamber 955B to pass by the second valve 908B, through the infusion conduit 936B and out of the infusion hole 908B for infusing the outer surface of the shell with a fluid.

In one embodiment, the third injection chamber 955C may be utilized for introducing fluid into the outer shell <NUM> for expanding the size of the tissue expander or withdrawing fluid from the outer shell <NUM> for reducing the size (i.e., deflating) the tissue expander <NUM>. In one embodiment, the tissue expander <NUM> desirably includes a third valve 958C coupled with the third injection chamber 955C. A second membrane 965B separates the first and second injection chambers 955A, 955B from the third injection chamber 955C. A needle <NUM> may be passed through the first and second membranes for selectively accessing each of the injection chambers 955A-955C. Under pressure, the third check valve 908C opens for allowing solution, such as saline solution, to flow through the valve 908C and into outer shell <NUM> for inflating the tissue expander <NUM>. Under vacuum, the third check valve 958C opens for drawing fluid from the outer shell <NUM> into the third injection chamber 955C for reducing the size of the tissue expander.

Referring to <FIG>, in one embodiment, a tissue expander <NUM> desirably includes an outer shell <NUM> with a first injection port 1004A and a second injection port 1004B secured to the outer shell <NUM>. In one embodiment, the first injection port 1004A includes a first injection chamber 1055A in communication with a first check valve 1058A and a second check valve 1058B. In one embodiment, the tissue expander <NUM> includes a first drainage conduit 1036A having a first end coupled with a drainage port in communication with the first check valve 1058A. The drainage conduit 1036A preferably includes a second end that is coupled with a drainage hole 1008A formed in the outer shell <NUM> of the tissue expander <NUM>. In one embodiment, when a vacuum is drawn inside the first injection chamber 1055A, the first check valve 1058A opens for allowing any fluid that has accumulated around the exterior of the tissue expander <NUM> to be drawn through the drainage hole 1008A, through the drainage conduit 1036A, past the open first check valve 1058A and into the first injection chamber 1055A for being withdrawn from the first injection chamber using a needle <NUM>.

In one embodiment, the second check valve 1058B is disposed between the first injection chamber 1055A and the first end of an infusion conduit 1036B. The infusion conduit 1036B has a second end connected with an infusion hole 1008B provided in the outer shell <NUM> of the tissue expander <NUM>. In one embodiment, when pressure is provided inside the first injection chamber 1055A, the second check valve 1058B opens for allowing infusion fluid to flow by the second check valve 1058B, through the infusion conduit 1036B and out of the infusion hole 1008B for bathing the exterior of the outer shell <NUM> with an infusion fluid.

In one embodiment, the second injection port 1004B of the tissue expander <NUM> may be utilized for inflating and deflating the outer shell <NUM> of the tissue expander <NUM>. In one embodiment, the second injection port 1004B desirably includes a second injection chamber 1055B and a third valve 1058C that opens under both pressure and vacuum. In one embodiment, when inflation fluid is injection via needle <NUM> into the second injection chamber 1055B, the fluid under pressure opens the third check valve 1058C and the fluid passes into the interior region of the outer shell <NUM> for inflating the tissue expander <NUM>. When a vacuum is drawn in the second injection chamber 1055B, the third check valve 1058C opens to allow the fluid inside the outer shell <NUM> be drawn into the second injection chamber 1055B for being removed from the outer shell <NUM> to deflate the tissue expander <NUM>.

<FIG> shows various systems and devices that may be used for creating a vacuum to drain fluid that has accumulated around the tissue expanders disclosed herein after the tissue expanders have been implanted inside patients. The devices may be coupled with the drainage conduits, injections chambers, and/or injection ports disclosed herein for drawing any fluid that has accumulated around the outsides of the outer shells of the respective tissue expanders. In one embodiment, In one embodiment, a system for generating a vacuum preferably includes a compressible bulb <NUM>. In one embodiment, vacuum may be created using a flexible, compressible reservoir <NUM> that draws a substantially constant vacuum to permit uniform removal of fluid from a surgical incision through a wound drain catheter, such as the surgical fluid evacuator disclosed in <CIT> In one embodiment, a system having a metered container <NUM> may be used for drawing a vacuum to permit the uniform removal of fluid from a surgical site.

Referring to <FIG>, in one embodiment, a drain <NUM>' preferably has an elongate, cylindrical core <NUM>' with four struts <NUM>' that project radially from the core <NUM>' along the longitudinal axis of the core. The radial struts <NUM>' are preferably of equal size and are spaced at equal angles relative to one another. Each of the outer ends of the radial struts <NUM>' have respective overhang portions <NUM>' which extend longitudinally throughout the length of the radial struts <NUM>'. As shown in <FIG>, in one embodiment, the overhang portions <NUM>' are thin arcuate members that extend an equal distance on either side of their respective radial struts <NUM>'. Thus, the overhand portions <NUM>' and the respective radial struts <NUM>' combine to form four T-shaped members. The overhang portions <NUM>' are sized to form a segmented circle at the periphery of the drain <NUM>', with small gaps between the adjacent overhang portions <NUM>'. Each of these gaps forms a longitudinal groove <NUM>', parallel to the longitudinal axis of the core <NUM>', and extending throughout the length of the drain <NUM>'. The core portion <NUM>', the radial struts <NUM>', and the overhand portions <NUM>' cooperate to form plural channels or lumens <NUM>' that extend along the length of the drain <NUM>'. The longitudinal grooves <NUM>' permit fluid communication between the respective lumens <NUM>' and a wound. In one embodiment, the width of the longitudinal grooves <NUM>' is approximately <NUM>-<NUM> times the outside diameter of the drain <NUM>', which ensures adequate tissue contact in the drainage area while inhibiting tissue growth or entry of debris, such as clots, into the lumens <NUM>'.

After breast reconstruction surgery, patients will have surgical drains placed to prevent blood and lymphatic fluid from building up under the skin, allowing for a quicker recovery. Some patients are sent home with drains that are implanted and connected to an external reservoir. Emptying these reservoirs can be traumatic as they have to measure and empty the reservoirs every morning. Patients cannot wait to have drains removed. Having a means to remove seroma fluid without the need for a drain being attached <NUM> hours a day is a great benefit to the patient.

Referring to <FIG>, in one embodiment, an injection port assembly <NUM> for an implant such as a tissue expander or a mammary implant preferably includes an injection dome <NUM> that is secured over an upper end of a needle guard <NUM> having one or more inflation ports <NUM> that are in fluid communication with an inflation chamber located inside the needle guard <NUM>, and a drainage port <NUM> that is in fluid communication with a drainage chamber located inside the needle guard <NUM>. The injection port assembly <NUM> may have one or more of the components and/or features disclosed in the injection port assembly <NUM> shown and described above in <FIG> of the present patent application.

Referring to <FIG>, in one embodiment, the injection port assembly <NUM> may include a magnet case <NUM> secured to an underside of the needle guard <NUM>. In one embodiment, the magnet case <NUM> desirably contains a magnet (not shown) that may be utilized by medical personnel for locating the center <NUM> of the injection dome <NUM>. After the injection port <NUM> has been implanted inside a patient (e.g., as part of a breast reconstruction procedure), the magnet disposed inside the magnet case <NUM> preferably enables medical personnel to locate the center <NUM> of the injection dome <NUM> so that a needle inserted into the injection dome <NUM> will be located inside the perimeter of the needle guard <NUM> and will not extend outside the needle guard where the needle could damage the shell of the implant or injure the patient.

Referring to <FIG>, in one embodiment, the needle guard <NUM> preferably includes a needle guard rim <NUM> having an upper end <NUM> and a lower end <NUM>. In one embodiment, the upper end <NUM> of the needle guard rim <NUM> is desirably open and adapted for receiving an underside of the injection dome <NUM> (<FIG>) as will be described in more detail herein. In one embodiment, the needle guard <NUM> desirably has a needle guard base <NUM> that is located at the lower end <NUM> of the needle guard rim <NUM> for closing the bottom of the needle guard <NUM>. In one embodiment, the needle guard rim <NUM> may have a cylindrical shape.

Referring to <FIG>, <FIG>, in one embodiment, the needle guard base <NUM> of the needle guard <NUM> preferably includes a barrier membrane support <NUM> that projects upwardly from the needle guard base <NUM> of the needle guard <NUM>. The barrier membrane support <NUM> preferably supports an underside of a barrier membrane to prevent tenting and/or collapsing of the barrier membrane when a distal end of a needle is pressed against and/or into the barrier membrane. In one embodiment, the barrier membrane support <NUM> preferably has a circular shape. The barrier membrane support may include two or more elements that are spaced from one another (e.g., opposing half circles). In one embodiment, the barrier membrane support may include a plurality of spaced posts that project from a top surface of the needle guard base <NUM>, which have upper ends that are adapted to engage a barrier membrane, such as a bottom surface of the barrier membrane, for supporting the barrier membrane inside the injection dome <NUM>.

Referring to <FIG>, and <FIG>, in one embodiment, the needle guard rim <NUM> of the needle guard <NUM> preferably includes a series of elongated slots 1224A-1224D that pass through the needle guard rim <NUM> adjacent the upper end <NUM> of the needle guard rim <NUM>. In one embodiment, the elongated slots 1224A-1224D desirably extend along longitudinal axes A<NUM> (<FIG>) that are parallel with a plane P<NUM> (<FIG>) defined by the needle guard base <NUM> of the needle guard <NUM>.

Referring to <FIG> and <FIG>, in one embodiment, the needle guard <NUM> desirably includes inflation ports 1206A, 1206B that are formed in the needle guard rim <NUM> and that are in fluid communication with the inflation chamber of the injection port assembly <NUM> (<FIG>). The needle guard <NUM> preferably includes a drainage port <NUM> that desirably passes through the needle guard rim <NUM> and is in fluid communication with the drainage chamber of the injection port assembly. Referring to <FIG>, in one embodiment, a barrier membrane <NUM> is located inside the needle guard <NUM> for isolating the inflation chamber <NUM> from the drainage chamber <NUM>. In one embodiment, the barrier membrane support <NUM> desirably supports an underside of the barrier membrane <NUM> for preventing the barrier membrane from tenting when a distal end of a needle assembly is pressed against the barrier membrane <NUM>.

Referring to <FIG>, in one embodiment, the injection dome <NUM> preferably has a lid <NUM> defining a first diameter D<NUM> and a base <NUM> that extends from an underside of the lid <NUM> having a second diameter D<NUM> that is smaller than the first diameter D1. In one embodiment, the lid <NUM> has a circular shape and the base <NUM> has a circular or cylindrical shape.

In one embodiment, the base <NUM> of the injection dome <NUM> has a bottom surface <NUM> having an annular groove <NUM> formed therein, which is adapted to receive the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM> (<FIG>) for securing the injection dome to the needle guard. Referring to <FIG>, the annular groove <NUM> formed in the bottom surface <NUM> of the base <NUM> extends from the bottom surface <NUM> toward the lid <NUM> of the injection dome <NUM>. Referring to <FIG>, in one embodiment, the annular groove <NUM> preferably defines a third diameter D<NUM> that is smaller than the second diameter D<NUM> of the base <NUM> of the injection dome <NUM>.

Referring to <FIG>, in one embodiment, the injection dome <NUM> may be assembled with the needle guard <NUM> by juxtaposing the bottom surface <NUM> of the base <NUM> of the injection dome <NUM> with the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM>. In one embodiment, the needle guard <NUM> has a first height H<NUM> and the injection dome <NUM> has a second height H<NUM> that is less than the first height H<NUM> of the needle guard.

In one embodiment, silicone material such as uncured silicone material or one or more uncured silicone sheets, or an adhesive material such as RTV may be used for securing the injection dome to the needle guard. In one embodiment, uncured silicone sheeting may be positioned at the upper end of the needle guard and, after the upper end of the needle guard and the uncured silicone sheets are inserted into the annular groove <NUM> of the injection dome <NUM>, the uncured silicone sheets may be cured using heat for adhering the injection dome to the needle guard.

In one embodiment, the injection port assembly <NUM> desirably includes the barrier membrane <NUM> that divides the inside of the needle guard into an inflation chamber <NUM> that is in communication with the inflation ports 1206A, 1206B formed in the needle guard rim <NUM> of the needle guard <NUM>, and a drainage chamber <NUM> that is in fluid communication with the drainage port <NUM> formed in the needle guard rim <NUM> of the needle guard <NUM>. In one embodiment, the barrier membrane <NUM> preferably extends across the entire width and/or diameter of the needle guard rim <NUM> of the needle guard <NUM> for isolating the inflation chamber <NUM> from the drainage chamber <NUM>. The barrier membrane support <NUM> desirably projects upwardly from the needle guard base <NUM> of the needle guard <NUM> for supporting an underside of the barrier membrane <NUM>.

Referring to <FIG>, in one embodiment, in order to assemble the injection dome with the needle guard, the annular groove <NUM> formed in the bottom surface <NUM> of the base <NUM> of the injection dome <NUM> is desirably juxtaposed and aligned with the cylindrical shaped needle guard rim <NUM> of the needle guard <NUM>. In one embodiment, the shapes and dimensions of the annular groove <NUM> of the injection dome and the cylindrical shaped needle guard rim <NUM> of the needle guard match one another.

In one embodiment, in order to secure the injection dome to the needle guard (e.g., form a hermetic seal), a joining component such as silicone sheeting <NUM> may be positioned around the needle guard rim <NUM> of the needle guard <NUM>. In one embodiment, the silicone sheeting <NUM> is aligned with and covers the elongated slots 1224A-1224D (<FIG>) located at the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM>. In one embodiment, the injection dome <NUM> is pressed onto the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM> so that that upper end <NUM> of the outer wall of the needle guard and the silicone sheeting <NUM> (<FIG>) are disposed within the annular groove <NUM> formed in the underside of the injection dome <NUM>. The silicone sheeting <NUM> preferably forms a secure, water-tight attachment (e.g., a heat seal, a seal made using a silicone adhesive) between the injection dome <NUM> and the needle guard rim <NUM> of the needle guard <NUM>.

Referring to <FIG>, in one embodiment, after the injection dome <NUM> has been secured over the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM>, the drainage chamber <NUM> of the injection port assembly <NUM>, which is in fluid communication with the drainage port <NUM>, is preferably located between a top surface of the barrier membrane <NUM> and the bottom surface <NUM> of the base <NUM> of the injection dome <NUM>. The inflation chamber <NUM>, which is in fluid communication with the inflation ports 1206A, 1206B extending through the needle guard rim <NUM> of the needle guard <NUM>, is preferably located between a bottom surface of the barrier membrane <NUM> and a top surface of the needle guard base <NUM> of the needle guard <NUM>. The barrier membrane support <NUM>, projecting from the top surface of the needle guard base <NUM> of the needle guard <NUM>, preferably supports the underside of the barrier membrane <NUM>.

Referring to <FIG>, in one embodiment, first and second anvils 1242A, 1242B may be utilized for securing the injection dome <NUM> to the needle guard <NUM> (<FIG>). In one embodiment, the first anvil 1242A includes a first concave surface 1244A that substantially matches the shape of the outer perimeter of the base <NUM> of the injection dome <NUM> (<FIG>) and the shape of the outer surface of the cylindrical-shaped outer wall of the needle guard. The second anvil 1242B desirably includes a second concave surface 1244B that also matches the shape of the outer surface of the base <NUM> of the injection dome <NUM> (<FIG>) and the outer surface of the cylindrical-shaped outer wall of the needle guard. The first and second anvils preferably oppose one another on opposite sides of the base of the injection dome.

Referring to <FIG>, in one embodiment, after the base <NUM> of the injection dome <NUM> has been pressed onto the upper end of the needle guard rim <NUM> of the needle guard <NUM> for contacting the silicone sheeting, the first and second concave surfaces 1244A, 1244B (<FIG>) of the first and second anvils 1242A, 1242B may be pressed against the outer surface of the base <NUM> for pressing the silicone sheeting <NUM> (<FIG>) into the elongated slots 1224A-1224D located at the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM>. In one embodiment, the first and second anvils 1242A, 1242B are pressed inwardly toward one another in the opposite directions DIR3, DIR4 for compressing the silicone sheeting <NUM> onto the outer surface of the base <NUM> of the injection dome <NUM> for bonding the injection dome to the needle guard and preferably forming a seal therebetween. In one embodiment, the bonding of the injection dome to the needle guard may include using one or more uncured silicone sheets or a silicone adhesive for securing the injection dome to the needle guard. In one embodiment, heat may be used for curing the one or more silicone sheets of the silicone adhesive. In one embodiment, the silicone material is located in the elongated slots formed at the upper end of the needle guard to provide anchor points for adhering the injection port to the needle guard. In one embodiment, after the first and second anvils 1242A, 1242B having been used for securing the injection dome <NUM> to the upper end of the needle guard <NUM>, the first and second anvils may be removed, whereupon the injection port assembly <NUM> has the configuration shown in <FIG>, <FIG>, and <FIG> of the present patent application.

In one embodiment, an injection port assembly has a configuration whereby a single needle having a moveable insert may be used for both inflating an implant shell and draining fluid that has collected around the outside of an implant shell. Referring to <FIG>, in one embodiment, an injection port assembly <NUM> preferably includes an injection dome <NUM> and a needle guard <NUM> having a needle guard rim <NUM> that is pressed into an annular groove <NUM> provided at an underside of the base of the injection dome <NUM>. The needle guard rim <NUM> of the needle guard <NUM> desirably includes first and second inflation ports 1306A, 1306B and a drainage port <NUM> that is located above the inflation ports. The injection port assembly <NUM> desirably includes a barrier membrane <NUM> that divides an interior region of the needle guard <NUM> into an inflation chamber <NUM>, which is located between an underside of the barrier membrane <NUM> and a top surface of a needle guard base <NUM> of the needle guard <NUM>, and a drainage chamber <NUM>, which is located between a top surface of the barrier membrane <NUM> and the bottom surface <NUM> of the base <NUM> of the injection dome <NUM>. The inflation chamber <NUM> is preferably in fluid communication with the inflation ports 1306A, 1306B formed in the needle guard rim <NUM> of the needle guard <NUM>, and the drainage chamber <NUM> is preferably in fluid communication with the drainage port <NUM> formed in the outer wall of the needle guard.

In one embodiment, a needle assembly <NUM> preferably includes a needle <NUM> having an elongated shaft <NUM> with a proximal end <NUM> and a distal end <NUM>. In one embodiment, the needle assembly <NUM> preferably includes an insert <NUM> that is disposed inside the elongated shaft <NUM> of the needle <NUM>. The insert <NUM> is preferably coupled with an actuator <NUM> that may be engaged for moving the insert along the longitudinal axis of the elongated shaft <NUM> of the needle <NUM>, between an extended position for aligning the distal end of the insert <NUM> with an inflation lumen <NUM> of the needle <NUM> and a retracted position for aligning the distal end of the insert <NUM> with a drainage lumen <NUM> of the needle <NUM>.

Referring to <FIG>, in one embodiment, the needle <NUM> of the needle assembly <NUM> (<FIG>) preferably includes the elongated shaft <NUM> of the needle having the proximal end <NUM> and the distal end <NUM> including a sharpened tip <NUM> that facilitates passing the distal end <NUM> of the elongated shaft <NUM> of the needle through an object such as the injection dome disclosed herein. In one embodiment, the needle <NUM> preferably includes the inflation lumen <NUM>, which is located at the distal end <NUM> of the elongated shaft <NUM>, and a drainage lumen <NUM>, which extends through the outer wall of the elongated shaft and is proximal to the inflation lumen <NUM>. As will be described in more detail herein, in one embodiment, when the distal end <NUM> of the elongated shaft <NUM> of the needle <NUM> is inserted into an injection dome of an injection dome assembly, the inflation lumen <NUM> is in fluid communication with the inflation chamber <NUM> of the injection port assembly <NUM> (<FIG>), and the drainage lumen <NUM> is in fluid communication with the drainage chamber <NUM> of the injection port assembly <NUM> (<FIG>).

Referring to <FIG>, in one embodiment, the needle <NUM> preferably includes an elongated conduit <NUM> that extends along the length of the elongated shaft <NUM> of the needle. The elongated conduit <NUM> is preferably in fluid communication with both the inflation lumen <NUM> and the drainage lumen <NUM>.

Referring to <FIG>, in one embodiment, the needle assembly <NUM> (<FIG>) preferably includes the insert <NUM> that is disposed inside the elongated shaft of the needle <NUM> (<FIG>). In one embodiment, the insert <NUM> preferably includes an elongated shaft <NUM> having an elongated conduit <NUM> that extends along the length of the insert from a proximal end <NUM> to a distal end <NUM> of the insert. The distal end <NUM> of the elongated shaft <NUM> of the insert desirably has a side port <NUM> that is in fluid communication with the elongated conduit <NUM> of the insert <NUM>. The distal end <NUM> of the elongated shaft <NUM> of the insert <NUM> is closed by a distal end wall <NUM>. The actuator <NUM> (<FIG>) is secured to the outer surface of the elongated shaft <NUM> of the insert <NUM> for allowing medical personnel to move the insert relative to the needle <NUM> (<FIG>) between an extended position in which the side port <NUM> of the insert is in fluid communication with the inflation lumen <NUM> (<FIG>) of the needle and a retracted position in which the side port <NUM> of the insert is in fluid communication with the drainage lumen <NUM> (<FIG>) of the needle.

Referring to <FIG>, in one embodiment, the side port <NUM> is formed in the outer wall of the elongated shaft <NUM> of the insert <NUM>. The side port <NUM> is preferably located adjacent the distal end <NUM> of the elongated shaft <NUM>. In one embodiment, the side port <NUM> is preferably in fluid communication with an elongated conduit <NUM> that extends along the length of the elongated shaft <NUM>. In one embodiment, the elongated conduit <NUM> preferably extends between the proximal end <NUM> and the distal end <NUM> of the elongated shaft <NUM> of the insert <NUM> (<FIG>).

Referring to <FIG>, in one embodiment, the insert <NUM> is preferably disposed within the elongated shaft <NUM> of the needle <NUM> to form the needle assembly <NUM> shown in <FIG>. The insert <NUM> preferably includes the side port <NUM> that is in fluid communication with the elongated conduit <NUM> that extends along the length of the insert <NUM>. The elongated shaft <NUM> of the needle <NUM> preferably includes the inflation lumen <NUM> that is located adjacent the distal end <NUM> of the elongated shaft <NUM>, and the drainage lumen <NUM> that is proximal to the inflation lumen <NUM>.

Referring to <FIG>, in one embodiment, the insert <NUM> is movable between the extended position shown in <FIG> and the retracted position shown in <FIG>. In the extended position shown in <FIG>, the side port <NUM> of the insert <NUM> is aligned with the inflation lumen <NUM> located at the distal end <NUM> of the elongated shaft <NUM> of the needle <NUM>. In the extended position shown in <FIG>, the outer wall of the elongated shaft <NUM> of the insert <NUM> covers the drainage lumen <NUM> of the needle <NUM> so that no fluid may pass through the drainage lumen <NUM> of the needle <NUM>.

In one embodiment, the insert <NUM> may be moved to the retracted position shown in <FIG> so that the side port <NUM> of the insert is aligned with the drainage lumen <NUM> of the elongated shaft <NUM> of the needle <NUM>. In the retracted position, the closed distal end wall <NUM> of the insert blocks the inflation lumen <NUM> of the needle <NUM> so that no fluid may pass into or out of the needle <NUM> through the inflation lumen <NUM> of the needle.

In one embodiment, the actuator <NUM> of the needle assembly <NUM> (<FIG>) may be used for repeatedly moving the insert <NUM> back and forth between the extended position shown in <FIG> and the retracted position shown in <FIG>. In the extended position of <FIG>, the side port <NUM> of the insert <NUM> is aligned with the inflation lumen <NUM> of the needle <NUM> so that fluid may pass out of the inflation lumen (e.g., for being introduced into the inflation chamber <NUM> (<FIG>) of the injection port assembly). When the insert <NUM> is shifted and/or moved into the retracted position shown in <FIG>, the side port <NUM> of the insert <NUM> is preferably aligned with the drainage lumen <NUM> of the needle <NUM> so that the elongated conduit of the insert is in fluid communication with the drainage chamber <NUM> (<FIG>) of the injection port assembly <NUM> (<FIG>).

Referring to <FIG> and <FIG>, in one embodiment, the distal end <NUM> of the elongated shaft <NUM> of the needle <NUM> may be inserted into the injection dome <NUM> of the injection port assembly <NUM> until the distal end <NUM> of the needle <NUM> abuts against the needle guard base <NUM> of the needle guard <NUM>. In one embodiment, the insert <NUM> may be shifted into the extended position so that the side port <NUM> of the insert <NUM> is aligned with the inflation lumen <NUM> of the needle <NUM>. With the insert <NUM> in the extended position shown in <FIG> and <FIG>, the distal end <NUM> of the needle <NUM> is in fluid communication with the inflation chamber <NUM> of the injection port assembly <NUM>, whereupon the needle may be used for directing fluid into the inflation chamber <NUM> for inflating a shell and/or providing an infusing fluid around the outside of the shell.

Referring to <FIG>, in one embodiment, the actuator <NUM> of the needle assembly <NUM> is connected with the elongated shaft of the insert <NUM> for moving the insert from the extended position shown in <FIG> to the retracted position shown in <FIG>.

Referring to <FIG> and <FIG>, in one embodiment, with the insert <NUM> in the retracted position, the side port <NUM> of the insert <NUM> is aligned with the drainage lumen <NUM> of the elongated shaft <NUM> of the needle <NUM>. The distal end wall <NUM> located at the distal end of the elongated shaft <NUM> of the insert <NUM> closes the inflation lumen <NUM> at the distal end <NUM> of the needle <NUM>. In the retracted position, the side port <NUM> of the insert <NUM> is aligned with the drainage lumen <NUM> of the needle <NUM> so that the needle <NUM> is in fluid communication with the drainage chamber <NUM> of the injection port assembly <NUM>. As a result, fluid that is drawn into the drainage port <NUM> may be sucked into the drainage lumen <NUM> for being removed from a proximal end of the needle <NUM>.

Referring to <FIG>, in one embodiment, an injection port assembly <NUM> may include a barrier membrane support <NUM> that is adapted to support a barrier membrane <NUM> that is located inside a needle guard. In one embodiment, the barrier membrane <NUM> preferably includes an inner barrier membrane <NUM> with a central opening <NUM> and an outer barrier membrane <NUM> having a donut-shaped opening <NUM> in its center.

In one embodiment, the barrier membrane support <NUM> preferably includes an annular outer wall <NUM> having an inner surface with an inner annular groove <NUM>, an annular inner wall <NUM> having an outer surface with an outer annular groove <NUM> and an inner surface with an inner annular groove <NUM>. In one embodiment, the barrier membrane support <NUM> preferably includes a central post <NUM> (<FIG>) that is surrounded by the inner annular wall <NUM>. The barrier membrane support <NUM> preferably has a bottom wall <NUM> that closes the bottom of the barrier membrane support <NUM>. The outer annular wall <NUM>, the inner annular wall <NUM>, and the central post <NUM> (<FIG>) preferably project away from the bottom wall <NUM> of the barrier membrane support <NUM>.

Referring to <FIG>, in one embodiment, the inner barrier membrane <NUM> is preferably pressed onto the central post <NUM> with the central post passing through the central opening <NUM> (<FIG>) of the inner barrier membrane <NUM>. The outer perimeter of the inner barrier membrane <NUM> is preferably seated within the inner annular groove <NUM> (<FIG>) formed in the inner annular wall <NUM> of the barrier membrane support <NUM>.

In one embodiment, the outer barrier membrane <NUM> is preferably pressed into the space between the outer annular wall <NUM> and the inner annular wall <NUM>. The outer perimeter of the outer barrier membrane <NUM> is preferably seated within the inner annular groove <NUM> of the outer annular wall <NUM>, and the inner perimeter of the outer barrier membrane <NUM> is preferably seated within the outer annular groove <NUM> formed in the inner annular wall <NUM>.

After the inner and outer barrier membranes <NUM>, <NUM> have been assembled with the barrier membrane support <NUM>, the barrier membrane <NUM> preferably divides the barrier membrane support <NUM> into an inflation chamber <NUM> that is disposed between an underside of the barrier membrane <NUM> and the top surface of the bottom wall <NUM> of the barrier membrane support <NUM> and a drainage chamber <NUM> that is located above the barrier membrane <NUM>.

Referring to <FIG>, in one embodiment, the barrier membrane support <NUM> and the barrier membrane <NUM> shown in <FIG> may be juxtaposed with an open upper end of a needle guard <NUM> having a needle guard rim <NUM>. In one embodiment, the bottom wall <NUM> of the barrier membrane support <NUM> is preferably juxtaposed with the opening at the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM>. The barrier membrane support <NUM> is preferably passed through the opening at the upper end <NUM> of the needle guard rim <NUM> of the needle guard <NUM> in the direction DIR5 until the bottom wall <NUM> of the barrier membrane support <NUM> abuts against a top surface of a needle guard base <NUM> of the needle guard <NUM>.

Referring to <FIG>, after the barrier membrane support <NUM> is fully inserted into the needle guard <NUM>, the bottom wall <NUM> of the barrier membrane support <NUM> preferably abuts against the needle guard base <NUM> of the needle guard <NUM>. The outer barrier membrane <NUM> preferably extends between and is supported by annular grooves formed in the respective outer annular wall <NUM> and inner annular wall <NUM> of the barrier membrane support <NUM>. The inner barrier membrane <NUM> is preferably supported by the inner annular wall <NUM> and the central post <NUM>. The barrier membrane support <NUM> preferably holds the inner and outer barrier membranes <NUM>, <NUM> at a position that is spaced away from the bottom wall <NUM> of the barrier membrane support. As a result, the barrier membrane <NUM> defines the inflation chamber <NUM> that is preferably located between an underside of the barrier membrane <NUM> and a top surface of the bottom wall <NUM> of the barrier membrane support <NUM>, and a drainage chamber <NUM> that is located above the barrier membrane <NUM>.

Referring to <FIG>, in one embodiment, an implant shell <NUM> preferably has a first expandable chamber <NUM> and a second expandable chamber <NUM> that is isolated from the first expandable chamber <NUM> by a membrane <NUM> that extends across the interior of the shell <NUM>. In one embodiment, the implant shell <NUM> desirably includes a multi-compartment injection dome <NUM> having a first fluid compartment <NUM> and a second fluid compartment <NUM> that is isolated from the first fluid compartment <NUM>.

In one embodiment, the first fluid compartment <NUM> of the injection dome <NUM> is in communication with the first expandable chamber <NUM> of the implant shell <NUM> via a first valve <NUM>. The second fluid compartment <NUM> of the injection dome <NUM> is desirably in fluid communication with the second expandable chamber <NUM> of the implant shell <NUM> via a second valve <NUM>. In one embodiment, when an injection needle <NUM> is used to introduce a first fluid into the first fluid compartment <NUM> of the injection dome <NUM>, the first expandable chamber <NUM> of the shell <NUM> may be expanded by the first fluid. When the needle <NUM> is used to deliver a second fluid into the second fluid compartment <NUM> of the injection dome <NUM>, the second expandable chamber <NUM> of the implant shell <NUM> may be expanded with the second fluid. The first and second fluids may have the same properties (e.g., both saline solutions) or different properties (e.g., the first fluid is saline solution and the second fluid is an antibiotic solution).

In one embodiment, the injection needle <NUM> may have a construction similar to the needle assembly <NUM> with the moveable insert <NUM> shown and described above in <FIG> of the present patent application. Thus, a needle may be inserted into the injection dome <NUM> and, without moving the position of the needle relative to the injection dome, the needle insert may be moved between a retracted position and an extended position for accessing both the first fluid compartment <NUM> and the second fluid compartment <NUM> of the injection dome <NUM>. In one embodiment, with the insert in a retracted position, the needle may be used for introducing fluid into the first fluid compartment <NUM> of the injection dome <NUM>. In one embodiment, with the insert in an extended position, the needle may be used for introducing fluid into the second fluid compartment <NUM> of the injection dome <NUM>.

In one embodiment, an implant shell may include two or more expandable chambers (e.g., three expandable chambers). In one embodiment, each of the two or more expandable chambers is associated with a different fluid compartment of an injection dome. For example, in an embodiment in which the implant shell has four expandable chambers, the injection dome may have four fluid chambers, whereby each fluid chamber of the injection dome is in fluid communication with a different one of the expandable chambers of the implant shell. In one embodiment, an injection dome may have more fluid chambers than the number of expandable chambers that are present in an implant shell. For example, an injection dome may have four fluid chambers in fluid communication with four respective expandable chambers of an implant shell and a fifth fluid chamber that is in fluid communication with a drainage conduit for draining fluids that collect around the outside of the implant shell.

Claim 1:
A tissue expander (<NUM>) having an integrated drain comprising:
a shell (<NUM>) having an injection port (<NUM>) opening and one or more drainage holes (<NUM>) formed in said shell that are spaced from said injection port opening;
an injection port assembly disposed in said injection port opening, wherein said injection port assembly forms a fluid-tight seal with said shell;
said injection port assembly including a needle guard (<NUM>) having a needle guard base (<NUM>) with a top surface;
a barrier membrane (<NUM>) disposed within said needle guard that overlies the top surface of said needle guard base, wherein said barrier membrane defines an inflation chamber (<NUM>) located between the top surface of said needle guard base and a bottom surface of said barrier membrane, and wherein said barrier membrane defines a drainage chamber (<NUM>) located within said needle guard that overlies a top surface of said barrier membrane;
one or more inflation ports (128A, 128B) in fluid communication with said inflation chamber for inflating and deflating said shell with a first fluid;
a drainage conduit (<NUM>) in fluid communication with and extending between said drainage chamber and said one or more drainage holes formed in said shell for draining a second fluid from outside said shell, wherein said drainage conduit comprises a second end (<NUM>) that is coupled with a drain (<NUM>), which, in turn, is in fluid communication with said one or more drainage holes that are formed in said shell;
a drainage manifold (<NUM>) that is aligned with and covers said one or more drainage holes formed in said shell.