Sinus stents and systems and methods for deploying stents within a patient's sinuses

Abstract

Systems and methods for deploying a stent within a frontal sinus. The stent includes a flexible foam and a membrane layer that are arranged in a stacked configuration and rolled up within a cartridge prior to deployment. The cartridge is removably coupled to an applicator device that includes an actuator. The membrane layer may include a polymer having a restoring force sufficient to deploy the stent and maintain the patency of the frontal sinus opening. The flexible foam layer may have a porosity greater than 80%, and an active agent may be within the flexible foam layer. The flexible foam layer may be bioresorbable, while the flexible membrane layer is biocompatible and non-biodegradable. The stent may include first and second body portions, wherein the first body portion deploys independently of the second body portion to maintain the stent within the frontal sinus. The contours of the first and second body portions may facilitate removal of the stent.

Description

[0001] Priority application

[0002] This application claims priority to and all benefits of U.S. Provisional Patent Application No. 62 / 834,628, filed April 16, 2019, which is incorporated herein by reference in its entirety. Background Art

[0003] Chronic sinusitis (CRS) is one of the most common healthcare problems in the United States. When sinusitis develops, the mucociliary clearance mechanism becomes less efficient, preventing normal mucus flow. The sinus membranes become congested, causing the sinuses to close. This poor ventilation and accumulation of mucus create the conditions conducive to bacterial infection.

[0004] Currently, medical management of CRS encompasses a wide range of treatment modalities, including oral antibiotics and corticosteroids, saline irrigation, and immunomodulators, but these approaches are often ineffective. For example, the amount of active agent from nasal sprays that reaches the target sinus tissue is very low, as a large portion has been found to be excreted through the gastrointestinal tract.

[0005] Functional endoscopic sinus surgery (FESS) is now a well-established, minimally invasive treatment option for patients with sinus disease. Furthermore, it is well known that long-term stent implantation within a few months after FESS can significantly reduce restenosis rates. However, there is a lack of adequate commercially available products that promote frontal sinus patency and mucosal restoration. Therefore, there is a need in the art for an improved stent and delivery system that allows for the direct administration of active agents into the mucosal wall in a manner that promotes drainage from the frontal sinuses and helps maintain patency between the frontal sinus cavity and the nasal cavity after FESS. Summary of the Invention

[0006] A first aspect is directed to a stent positionable within a frontal sinus cavity. The stent comprises a flexible foam layer having a porosity greater than 80%. The flexible foam layer comprises polyurethane comprising amorphous segments and crystalline segments formed by hydrogen bonding. An active agent is within the flexible foam layer. The stent further comprises a flexible film layer arranged in a stacked configuration and comprising a polymer structured to form hydrogen bonds with the crystalline segments of the flexible foam layer at a bonding interface. The flexible foam layer and the flexible film layer are configured to be rolled up to assume a cylindrical profile prior to insertion into the frontal sinus cavity, such that the flexible foam layer at least partially defines an outer annular layer of the stent and the flexible film layer at least partially defines an inner annular layer of the stent. The flexible film layer has a restoring force sufficient to unfold the stent and to bring the outer annular layer of the flexible foam layer into direct contact with the mucosa of the frontal sinus cavity when positioned in an unrestrained state within the frontal sinus cavity.

[0007] In some embodiments, removing the flexible film layer from the flexible foam layer results in cohesive failure of the foam layer at the bonding interface. The bonding interface is free of adhesive, and the flexible film layer and the flexible foam layer are directly bonded to each other via hydrogen bonding. There may be substantially no covalent bonds between the flexible film layer and the flexible foam layer.

[0008] In some embodiments, the crystalline segments of the flexible foam layer comprise the reaction product of 1,4-butanediol and 1,4-diisocyanatobutane. The molecules within the polyurethane foam layer can be arranged such that the crystalline segments and the amorphous segments are stacked in an alternating configuration to provide a three-dimensional porous structure that is reinforced by hydrogen bonding between the stacked crystalline segments.

[0009] In some embodiments, the stent further comprises a first body portion and a second body portion, the first body portion and the second body portion being coupled at a joint extending partially between opposing sides of the stent, such that the first body portion and the second body portion are configured to roll up and / or unfold independently except at the joint. Each of the first body portion and the second body portion may comprise the flexible foam layer and the flexible membrane layer. The first body portion and the second body portion may be separated at a boundary defined between the opposing sides and including the joint. The stent further comprises a cutout extending inwardly from the opposing sides, the cutout comprising a first layer associated with the first body portion and a second layer associated with the second body portion. Each of the first layer and the second layer of the cutout may be angled relative to the boundary. The angle of the first layer of the cutout relative to the boundary may be within a range of approximately 25 degrees and 75 degrees. The angle of the second layer of the cutout relative to the boundary may be within a range of approximately 25 degrees and 75 degrees. The first layer and the second layer may be continuous with each other and form a cutout having a generally parabolic shape. The flexible foam layer may have a first thickness defined between a first outer surface and the interface, and the flexible membrane layer may have a second thickness defined between a second outer surface opposite the first outer surface and the bonding interface. The first thickness may be greater than the second thickness. The opposing sides may be first opposing sides, and the bracket further includes second opposing sides extending between the first opposing sides. The second opposing sides may be arcuate in shape and intersect the first opposing sides at a rounded corner.

[0010] In some embodiments, the flexible membrane layer may comprise polysiloxane. The flexible membrane layer may comprise polyurethane. The flexible membrane layer may comprise a bioabsorbable polymer comprising silanol groups and / or urethane groups. The flexible foam layer may be bioabsorbable.

[0011] In some embodiments, the active agent comprises a molecule comprising at least one hydrogen atom bound to a nitrogen, oxygen, or fluorine atom.The active agent may be selected from the group consisting of a corticosteroid, a hemostatic agent, and combinations thereof.

[0012] A second aspect of the present disclosure relates to a method for deploying a stent according to the first aspect of the present disclosure, and optionally any corresponding embodiment thereof.

[0013] A third aspect of the present disclosure relates to a disposable cartridge assembly for deploying a stent according to the first aspect of the present disclosure, and optionally any corresponding embodiments thereof.

[0014] In some embodiments, the cartridge assembly includes a tubular sheath comprising at least one sidewall defining a proximal end, a distal end opposite the proximal end, and an inner lumen extending between the proximal and distal ends and defining a sheath volume, the sheath volume being sized to receive substantially the entire rolled-up stent between the proximal and distal ends. A cap portion can be coupled to the proximal end of the tubular sheath. The cap portion can include a cap body, a lip, and a coupling feature. The cap body can define an orifice communicating with the inner lumen of the tubular sheath, the orifice being sized to receive a plunger element of an applicator device. The lip can extend outwardly from the cap body to define a surface configured to abut the distal end of the applicator device when the disposable cartridge is coupled to the applicator device. The coupling feature can be disposed on the cap body, wherein the coupling feature is configured to removably engage a complementary coupling feature of the applicator device. The tubular sheath can be flexible and sized to be inserted into the frontal sinus cavity. The lip can be annularly disposed around the cap body, having a cylindrical profile. The orifice of the cap may be coaxial with the lumen of the tubular sheath. The respective diameters of the lumen of the tubular sheath and the orifice of the cap may be substantially equal. The coupling feature may comprise deflectable fingers spaced circumferentially around the cap.

[0015] A fourth aspect of the present disclosure relates to a method of operating the cartridge assembly according to the third aspect of the present disclosure to deploy a stent according to the first level of the present disclosure, and optionally, any corresponding embodiments thereof.

[0016] A fifth aspect of the present disclosure relates to a system for placing a stent into a frontal sinus cavity. An applicator device includes a housing, an actuator, and a drive member coupled to the actuator. The housing defines a hole and is adapted to be grasped by a single hand of a user. The drive member is configured to move within the hole in response to one or both of the housing and the actuator receiving input from the user. A disposable cartridge is removably coupled to the housing and includes a tubular sheath defining an inner cavity, and a cap portion coupled to the tubular sheath and removably coupled to the housing of the applicator device. The system includes a stent according to the first aspect of the present disclosure, and optionally, any corresponding embodiment thereof. The stent is configured to be rolled up and inserted into the tubular sheath. The flexible membrane layer has a restoring force sufficient to deploy the stent when positioned in an unrestricted state in the frontal sinus cavity.

[0017] In some embodiments, the system comprises a cartridge assembly according to the third aspect of the present disclosure, and optionally, any corresponding embodiment thereof.

[0018] In some embodiments, the inner annular layer of the rolled stent defines an internal passage. The drive member may include a distal end opposite the proximal end coupled to the actuator. A mandrel may extend from the distal end and pass through the internal passage of the stent when the stent is disposed within the flexible sheath. The cap portion may define an orifice that communicates with the lumen of the tubular sheath. The mandrel of the drive member may extend through the orifice of the cap portion when the cap portion is coupled to the housing. The drive member may also include a plunger element from which the mandrel extends. The orifice of the cap portion is sized to receive the plunger element of the applicator device when the cap portion is coupled to the housing. The orifice may be sized to removably receive the drive member of the applicator device such that the drive member extends through the orifice and the lumen of the tubular sheath when the stent is deployed from the disposable cartridge. The housing and the cap portion may also include complementary coupling features configured to removably couple the disposable cartridge to the applicator device. At least a portion of the housing may be flexible, and at least a portion of the drive member may be compliant and configured to receive another input from a user, impart a desired curve to the disposable cartridge, and maintain the desired curve of the disposable cartridge relative to the housing upon release of the other input. The actuator may include a push rod movably disposed within a bore of the housing.

[0019] A sixth aspect of the present disclosure relates to a method of operating a system according to the fifth aspect of the present disclosure, and optionally, any corresponding embodiments thereof.

[0020] A seventh aspect relates to a stent positionable within a frontal sinus cavity. The stent comprises a flexible foam layer and a flexible membrane layer arranged in a stacked configuration. The flexible foam layer and the flexible membrane layer are configured to be rolled up prior to insertion into the frontal sinus cavity. The flexible membrane layer has a restoring force sufficient to unfold the stent and force the flexible foam layer into direct contact with the mucosa of the frontal sinus cavity when positioned unrestrained within the frontal sinus cavity.

[0021] In some embodiments, the stent of the seventh aspect can include any corresponding embodiment of the stent according to the first aspect of the present disclosure. The stent can be deployed with the disposable cartridge assembly according to the third aspect of the present disclosure, and optionally, any corresponding embodiment thereof, and can be operated with the system according to the fifth aspect of the present disclosure, and optionally, any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Advantages of the present disclosure will be readily appreciated as they become better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings.

[0023] Figure 1 is a perspective view of a system for deploying a stent into a sinus cavity.

[0024] Figure 2 yes Figure 1 Exploded view of the system.

[0025] Figure 3 yes Figure 1 A cross-sectional view of the system taken along section line 3-3.

[0026] Figure 4A is a front view of the bracket in the unrestrained state.

[0027] Figure 4B is a front view of another bracket in an unrestrained state.

[0028] Figure 4C is a front view of another bracket in an unrestrained state.

[0029] Figure 4D is a front view of another bracket in an unrestrained state.

[0030] Figure 5 is a plan view of a stent in an unconstrained state, the stent comprising a flexible membrane layer and a flexible foam layer arranged in a stacked configuration.

[0031] Figure 6 is a plan view of a stand including an unfolded first body portion and a rolled second body portion.

[0032] Figure 7is a front view of a bracket including an unfolded first body portion and a rolled second body portion.

[0033] Figure 8 is a front view of another stent having an unfolded first body portion and a rolled second body portion.

[0034] Figure 9 is a perspective view of a stent in an expanded configuration prior to insertion into a disposable cartridge.

[0035] Figure 10 is a perspective view of the stent in a rolled configuration prior to insertion into a disposable cartridge.

[0036] Figure 11 is a perspective view of a holder disposed within a disposable cartridge.

[0037] Figure 12 is a perspective view of a stent disposed within a disposable cartridge prior to guiding a mandrel of an applicator device through an interior passage defined by the stent.

[0038] Figure 13 is a perspective view of a holder disposed within a disposable cartridge prior to coupling the disposable cartridge with an applicator device.

[0039] Figure 14 is a perspective view of a holder disposed within a disposable cartridge coupled to an applicator device.

[0040] Figure 15 is a perspective view of the system prior to movement of the housing relative to the plunger of the applicator device.

[0041] Figure 16 is a perspective view of the system after the housing has been moved relative to the plunger to deploy the stent out of the disposable cartridge.

[0042] Figure 17 is an illustration of a portion of the human head identifying certain structures and areas of the frontal sinus. DETAILED DESCRIPTION

[0043] Figure 1-3 A method for deploying a stent 32 to a patient's frontal sinus (FS) is shown (see FIG. Figure 17) in the system 30. The system 30 addresses the challenges of visualization difficulties and complex anatomy typically associated with frontal sinus surgery. The system 30 may be particularly well-suited for functional endoscopic sinus surgery (FESS), a minimally invasive surgical technique that opens the sinus air cells and ostia under direct visualization. In one example, a stent 32 is deployed within the frontal sinus after FESS to reduce, minimize, and / or eliminate restenosis of the frontal sinus opening (FSO) (i.e., ostium), which is one of the primary postoperative indicators of long-term outcome associated with chronic sinusitis (CRS). The system 30 may also be used to treat conditions such as inflammation, mucosal enlargement, polyposis, and adhesions, thereby reducing symptom recurrence and / or the need for further surgical intervention. In addition, in a manner to be further described, the system 30 may facilitate improved delivery of locally administered therapies (e.g., antibiotics, corticosteroids, immunomodulators, etc.) to the mucosal wall, wherein a greater portion of the active agent in the treatment reaches the target tissue.

[0044] System 30 includes a stent 32, an applicator device 34, and a cartridge 36, each of which will be described in turn below. In the broadest sense, applicator device 34 is configured to receive input from a user and deploy stent 32 from cartridge 36.

[0045] Further references Figure 4A-8 , the bracket 32 ​​includes a flexible foam layer 38, and a flexible membrane layer 40 coupled to the flexible foam layer 38, for example, coupled to the flexible foam layer 38 at a bonding interface 42. The flexible foam layer 38 and the flexible membrane layer 40 can be arranged in a stacked configuration, wherein the flexible foam layer 38 and the membrane layer 40 have a common contour, shape and / or size. For example, Figure 4A A variation of a bracket 32a is shown that is rectangular in plan view, with a perimeter 44 of the bracket 32 ​​defined by an upper side 46, a lower side 48, and opposing lateral sides 50. Each of the flexible foam layer and the membrane layer 38, 40 can share or define a portion of the upper side 46, the lower side 48, and the opposing lateral sides 50. In other words, the upper side 46, the lower side 48, and the opposing lateral sides 50 can be at least partially defined by the thickness of each of the flexible membrane layer 40 and the flexible foam layer 38 (see, for example, FIG. Figure 5 ).

[0046] The thicknesses of the flexible foam and membrane layers 38, 40 can be the same or different. In one example, the flexible foam layer 38 has a first thickness defined between the first outer surface 52 and the bonding interface 42, and the flexible membrane layer 40 has a second thickness defined between the bonding interface 42 and a second outer surface 54 opposite the first outer surface 52. Figure 5 The thickness of the flexible foam layer 38 is shown to be greater than the thickness of the flexible membrane layer 40. It is contemplated that additional layers may be included in the bracket 32.

[0047] The stent 32 is configured to be rolled to assume a substantially cylindrical profile for insertion through the nasal passage (NP) and through the frontal sinus opening into the frontal sinus cavity (FSC) (see FIG. Figure 10 and 17 ), and the flexible membrane layer 40 has sufficient restoring force to be sufficient to deploy the stent 32 once the stent 32 is positioned within the frontal sinus cavity and is unrestricted. In other words, the stent 32 can be thin enough to roll onto itself while also being able to rebound upon itself after insertion into the frontal sinus cavity. When partially or fully rolled up, the outer annular aspect 56 of the stent 32 is small enough in size to be inserted through, for example, the nasal passage, sinus opening, frontal sinus cavity, etc. The deployment or rebound facilitates patency of the frontal sinus cavity and promotes improved drainage. Furthermore, this is achieved by the restoring force of the material forming the flexible membrane layer 40, unlike known devices that require discrete reinforcing elements, etc. Such known devices can be associated with focal pressure areas on sensitive anatomical structures of the frontal sinus cavity and / or areas of varying patency of the internal channel defined by the device. Among the advantages to be explained, the stent 32 of the present disclosure achieves a more uniform deployment to improve patient comfort and the internal channel 57 defined by the rolled or partially deployed stent 32 within the frontal sinus (see Figure 6 When rolled up, the inner annular layer 58 opposite the outer annular layer 56 can define an interior channel 57 of the generally cylindrical profile of the stent 32.

[0048] Return to Figures 4A-4D , the bracket 32 ​​may include a first body portion 60 and a second body portion 62. Each of the first and second body portions 60, 62 may include a flexible foam layer and a membrane layer 38, 40. The first and second body portions 60, 62 are coupled to each other at a joint 64 so that the bracket 32 ​​may be of unitary construction. Figure 4AThe stent 32a of FIG. 3 shows a joint 64 generally defined between slits 66 extending inwardly from both lateral sides 50 of the stent 32. The length of the first body portion 60 on one side of the slit 66 can be greater than the length of the second body portion 62 on the other side of the slit 66. The first and second body portions 60, 62 are configured to be rolled and unfolded independently relative to each other except at the joint 64. Because the first and second body portions 60, 62 are configured to be rolled and unfolded independently relative to each other, the first body portion 60 can help maintain the stent 32 within the frontal sinus cavity. In a manner that will be further explained, the stent 32 can be positioned through the frontal sinus opening with the first body portion 60 within the frontal sinus cavity and the second body portion 62 located within the nasal passage (NP) in communication with the frontal sinus cavity opposite the frontal sinus opening. Depending on the relative sizes of the frontal sinus cavity and the nasal passage, the first body portion 60 is expanded to a greater extent than the second body portion 62, and more specifically to a degree that interferes with the anatomical structures defining the frontal sinus opening to retain the stent 32 within the frontal sinus (FS). The second body portion 62 is expanded to a lesser extent than the first body portion 60 to seat against or be pushed against the mucosal wall (MW) of the frontal sinus opening, thereby maintaining sinus patency and delivering the active agent within the flexible foam layer to the mucosal wall (see Figure 17 ).

[0049] exist Figure 4B In another embodiment of the stent 32b, a notch 68 extends inwardly from both lateral sides 50 of the stent 32 to define the joint 64. The notch 68 can be defined between an upper surface 70 associated with the first body portion 60 and a lower surface 72 associated with the second body portion 62. The slit 66 or notch 68 can be pre-fabricated or performed by the physician near or at the time of placement. In one example, the slit 66 or notch 68 can be cut using conventional scissors.

[0050] The stent 32 is deployed within the frontal sinus and the first body portion 60 interferes with the anatomical structures defining the frontal sinus opening, and ultimately the stent 32 may need to be removed from the frontal sinus. The interference of the first body portion 60 with the anatomical structures needs to be overcome to remove the stent 32. This may include applying a tensile force to the stent 32, such as using a surgical instrument, whereupon the tensile force causes the first body portion 60 to collapse (e.g., partially roll up) onto itself as the stent 32 is removed through the frontal sinus opening and the nasal passage. Figure 4A and 4B The first body portion 60, such as the upper face 70, is oriented generally perpendicular to the direction of removal of the stent 32, which may require unnecessary tension and / or irritate sensitive anatomy of the frontal sinus. Figure 4C and 4D, shows a variant of the bracket 32c, 32d, in which the cutout 68 is shaped to facilitate removal of the bracket 32. In particular, the upper and / or lower levels 70, 72 are angled relative to the limit 74 defining the joint 64. Figure 4C and 4D The boundary 74 is shown extending between the lateral sides 50 of the bracket 32. The upper surface 70 is oriented upwardly at an angle α relative to the boundary 74. The angle α can be in the range of about 25 to 75 degrees, and more specifically in the range of about 40 to 60 degrees. The lower surface 72 is oriented downwardly at an angle α relative to the boundary 74. The angle α can be in the range of about 25 to 75 degrees, and more specifically in the range of about 40 to 60 degrees. In addition, the contour of the intersection of the upper and lower surfaces 70, 72 can be constructed to remove any sharp edges. For example, the upper and lower surfaces 70, 72 can be considered to be continuous with each other to form a cutout 68 that is substantially parabolic in shape, as shown in FIG. Figure 4C and 4D As shown. Similarly, Figure 4D The upper side 46 and the lower side 48 are shown as being arcuately shaped between the opposing lateral sides 50 and intersecting the opposing lateral sides 50 at rounded corners. The angling of the upper layer 70 facilitates easier folding and collapsing of the first body portion 60 formed by the flexible foam and membrane layers 38, 40 onto itself. Moreover, because the upper layer 70 is angled away from the direction of removal, the forces from the upper layer 70 contacting the sensitive nasal anatomy are significantly reduced. Furthermore, the upper and lower layers 70, 72 can facilitate easy loading of the stent 32 into the cartridge 36.

[0051] Now refer to Figure 7 and 8 , stent variations 32a, 32c are shown in positions within the frontal sinus proximate to a deployed or unconstrained state. The flexible membrane layer 40 of the first body portion 60 deploys the stent 32 against the anatomy. Figure 8 The stent 32c of the embodiment of the present invention shows that the first body portion 60 tapers from the upper layer 70. In addition, the flexible membrane layer 40 of the second body portion 62 facilitates direct contact between the outer annular layer 56 of the flexible foam layer 38 and the mucosal wall of the frontal sinus cavity. The inner annular layer 58 of the flexible membrane layer 40 of the second body portion 62 defines an internal channel 57 for drainage, breathing, etc.

[0052] Because the stent 32 includes a flexible foam layer 38 bonded to the flexible membrane layer 40 in a stacked configuration, the advantageous material properties associated with each of the layers 38, 40 can be fully realized. This bonding can be facilitated by using a flexible foam layer 38 comprising a polyurethane comprising amorphous segments and crystalline segments, as will be described in more detail. In many examples, the properties of the flexible foam layer 38 are configured to swell (or not swell) when exposed to moisture within the frontal sinus. To this end, the flexible foam layer 38 can include a phase separation polymer. In addition, good compressibility can be achieved, wherein the phase separation polymer of the flexible foam layer 38 maintains its structure (particularly its compressive strength) when absorbed or saturated with a liquid (e.g., blood or mucus). The mechanical, structural, and chemical properties of the foamed phase separation polymer are primarily determined by the composition (structure) of the polymer used. To this end, the selection of reactants for forming the phase separation polymer provides a means for controlling and regulating the mechanical, structural, and chemical properties of the phase separation polymer.

[0053] As used herein, the term "phase-separated polymer" refers to a polymer comprising soft (amorphous) segments and hard (crystalline) segments, wherein the phase transition temperature of the hard segments is at least mammalian body temperature (typically 37°C for humans), and when a foam prepared from such a polymer is applied to the human or animal body for a sufficient period of time, a phase-separated morphology is manifested. In addition, the polymer exhibits a phase-separated morphology when exposed to temperature conditions comparable to those of the human or animal body. Phase-separated polymers are characterized by the presence of at least two immiscible or partially miscible phases having different morphologies under normal ambient conditions. In a single material, there may be a rubbery phase and a crystalline phase (at a temperature above the glass transition temperature of the amorphous phase and below the melting temperature of the crystalline phase) or a glassy phase and a crystalline phase (at a temperature below the glass transition temperature of the amorphous phase). Furthermore, at least two amorphous phases may be present at temperatures between two phase transitions (e.g., a glassy phase and a rubbery phase). Above the temperature of the highest phase transition (i.e., melting or glass transition temperature), the liquid and rubber phases, or the two rubber phases, respectively, may form a phase-mixed morphology, or they may remain immiscible. Immiscible liquid and / or rubber phases typically result in a polymer with a phase-separated morphology that does not have the initially expected mechanical properties under normal ambient conditions.

[0054] In some examples, the phase separating polymer has a porosity greater than 50, 60, 70, or 80%. Alternatively, the phase separating polymer has a porosity of from 50 to 99%, from 50 to 96%, from 60 to 96%, from 70 to 96%, from 80 to 93%, from 80 to 90%, from 80 to 87%, from 80 to 84%, from 83 to 99%, from 85 to 99%, from 89 to 99%, from 92 to 99%, from 95 to 99%, from 83 to 96%, from 86 to 93%, from 92 to 98%, from 95 to 98%, or 90%.

[0055] In some examples, the phase separation polymer has a range of 0.01 to 1.0 g / cm 3 Alternatively, the foam density can be from 0.01 to 0.5, 0.01 to 0.3, 0.01 to 0.1, 0.01 to 0.09, 0.01 to 0.08, 0.01 to 0.07, 0.01 to 0.06, 0.01 to 0.05, 0.01 to 0.04, 0.01 to 0.03, 0.02 to 0.08, 0.04 to 0.08, 0.05 to 0.08, 0.06 to 0.08, 0.02 to 0.08, or 0.03 to 0.07 g / cm 3 In certain embodiments, the phase-separated polymer has a porosity of 85-99% and a density of 0.03-0.07 g / cm 3 It should be understood that the term "foam density" as used throughout this disclosure refers to the density of the foam, calculated as the mass of phase-separated polymer per unit volume of a particular foam portion. Therefore, if the particular foam portion includes an active agent, the mass of the active agent present in the particular foam portion is disregarded when calculating the foam density.

[0056] The phase separation polymer can be selected from polyesters, polyethers, polyhydroxy acids, polylactones, polyetheresters, polycarbonates, polydioxanes, polyanhydrides, polyurethanes, polyester (ether) urethanes, polyurethane ureas, polyamides, polyesteramides, polyorthoesters, polyamino acids, polyphosphonates, polyphosphazenes, and combinations thereof. Such polymers are described in International Publication No. 99 / 64491, the entire contents of which are incorporated herein by reference.

[0057] As described above, phase separation polymers include soft (amorphous or non-crystalline) segments and hard (crystalline) segments. As used herein, the term "amorphous" refers to a segment present in the phase separation polymer that has at least one glass transition temperature lower than the temperature of the human or animal body cavity in which the foam is filled, and may also refer to a combination of amorphous and crystalline segments that are completely amorphous when filled in the human or animal body. For example, the PEG in the prepolymer may be crystalline in pure form, but may be amorphous when included in the R segments of the polyurethane of formula (I). When included in the R segments of the polyurethane of formula (I), the longer PEG segments may also be partially crystalline, but will become amorphous ("dissolved") when placed in contact with water. Therefore, this longer PEG segment is the soft segment of the phase separation polymer of formula (I), while the hard segment should remain crystalline in nature to provide sufficient support for the specific foaming portion in a wet and filled state over a period of time.

[0058] As used herein, the term "crystalline" refers to segments present in a phase separated polymer that are crystalline when filled into the human or animal body, ie, have a melting temperature above the temperature of the human or animal body into which the occlusive device is inserted.

[0059] As used herein, a "hydrophilic segment" refers to a segment comprising at least one, preferably at least two, and more preferably at least three hydrophilic groups, which can be provided, for example, by COC or ether linkages. A polyether segment can thus provide a hydrophilic segment. The hydrophilic segment can also be provided by a polypeptide, poly(vinyl alcohol), polyvinyl pyrrolidone), or poly(hydroxyethyl methacrylate). The hydrophilic segment is preferably derived from a polyalkylene glycol, such as polyethylene glycol, polypropylene glycol, or polybutylene glycol. A preferred hydrophilic segment is a polyethylene glycol (PEG) segment.

[0060] As used herein, the term "segment" refers to a polymer structure of any length. In the field of polymer technology, long polymer structures are generally referred to as blocks, while short polymer structures are generally referred to as segments. It should be understood that both of these conventional meanings are included in the term "segment" as used herein.

[0061] In one specific example of the present application, the phase separation polymer has the formula:

[0062] -[R-Q1[-R'-Z1-[R”-Z2-R'-Z3] p -R"-Z4] q -R'-Q2]n- (I)

[0063] wherein R is selected from one or more aliphatic polyesters, polyetheresters, polyethers, polyanhydrides and / or polycarbonates, and optionally at least one R comprises a hydrophilic segment, R' and R" are independently C1-C 10wherein the phase separation polymer comprises an alkyl group, a C-C alkylene group optionally substituted with a C-C alkyl group substituted with a halogen or protected S, N, P or O moiety and / or a C-C alkylene group containing S, N, P or O in the alkylene chain, Z1-Z4 are independently amide, urea or carbamate, Q1 and Q2 are independently urea, carbamate, amide, carbonate, ester or anhydride, n is an integer from 5 to 500, and p and q are independently 0 or 1, provided that when q is 0, R is at least one amorphous aliphatic polyester, polyether, polyanhydride and / or polycarbonate segment, optionally with at least one crystalline polyether, polyester, polyetherester or polyanhydride segment. As represented by formula (I), the simplest form of the phase separation polymer has the formula: -R-Q1-R'-Q2-, i.e., when q=0.

[0064] The amorphous segment is contained in the -R- portion of the polymer according to formula (I). In the case where q=1, the Q1[-R'-Z1-[R"-Z2-R'-Z3] p -R"-Z4] q The -R'-Q2 moieties represent crystalline segments. In this particular example, the amorphous and crystalline segments alternate, providing hard segments with uniform block lengths.

[0065] As described above, R can represent a mixture of two or more different types of aliphatic polyesters, polyetheresters, polyethers, polyanhydrides and / or polycarbonates, the mixture including amorphous and crystalline types, so that both are included in a specific foaming portion. In the case of a mixture of amorphous and crystalline R segments provided in the polymer according to formula (I), at least one hydrophilic segment is optionally provided in at least one amorphous R segment. R can be derived in particular from the cyclic monomers lactide (L, D or LD), glycolide, ε-caprolactone, δ-valerolactone, trimethylene carbonate, tetramethylene carbonate, 1,5-dioxepane-2-one, para-dioxanone and combinations thereof and optionally polyethylene glycol, polypropylene glycol, polybutylene glycol and combinations thereof. In certain examples, R is an amorphous polyester derived exclusively from lactide and ε-caprolactone, with a molecular weight between 1000 and 4000. In one example, R is about 25 wt.% lactide, about 25 wt.% ε-caprolactone, and about 50 wt.% polyethylene glycol.

[0066] In the phase-separating polymer according to formula (I), Q1 and Q2 can be selected from amide, urea, carbamate, carbonate, or anhydride groups, and Z1 to Z4 should be selected from amide, urea, or carbamate groups so that at least four hydrogen-bonding groups are present continuously in the crystalline segment. The group R' in -Z2-R'-Z3- can be different from or similar to R' in -Q1-R'-Z1- or -Z4-R'-Q2-.

[0067] R optionally includes a hydrophilic segment and such a hydrophilic segment may very well be an ether segment, for example a polyether segment derived from a polyether compound such as polyethylene glycol, polypropylene glycol or polybutylene glycol. In addition, the hydrophilic segment included in R may be derived from a polypeptide, poly(vinyl alcohol), polyvinyl pyrrolidone or poly(hydroxyethyl methacrylate). The hydrophilic segment is preferably a polyether, for example a poly(alkylene glycol), such as poly(ethylene glycol), poly(propylene glycol) or poly(butylene glycol).

[0068] In some examples, the amorphous segment includes a hydrophilic segment. The hydrophilic segment may include polyethylene glycol in an amount of 1-80 wt.%, more preferably 5-60 wt.%, even more preferably 20-50 wt.%, and most preferably 50 wt.%, based on the total weight of the hydrophilic segment. In some examples, the phase separation polymer is a polymer according to Formula I, wherein R' is (CH2)4, R" is (CH2)4, or both R and R" are (CH2)4. For example, Z1-Z4 may be a carbamate.

[0069] It should be understood that the foams described herein are composed of a plurality of polymer chains, each comprising a phase-separating polymer, such as a polyurethane. In many examples, the foams are substantially free of any covalent crosslinks between the polymer chains contained in the foam. In the context of this disclosure, the term "substantially free of any covalent crosslinks" means that a polymer chain has fewer than 20, fewer than 10, fewer than 6, fewer than 4, or fewer than 2 covalent bonds with other polymer chains contained in the foam. In some examples, the foams are free of any covalent crosslinks between the polymer chains contained in the foam. In other words, each polymer chain is not covalently crosslinked with any other polymer chain contained in the foam.

[0070] As used herein, the term "hydrogen bonding" refers to the partial electrostatic attraction between a hydrogen (H) atom bonded to a more electronegative atom or group, such as nitrogen (N), oxygen (O), or fluorine (F)—a hydrogen bond donor—and another adjacent atom with a lone pair of electrons—a hydrogen bond acceptor. In polyurethanes, hydrogen bonding between carbonyl and NH groups is one of the primary driving forces for phase separation. Hydrogen bonding can be intermolecular (occurring between molecules that are separating) or intramolecular (occurring between parts of the same molecule).

[0071] In this example, the foam described herein comprises hard / crystalline segments and soft / amorphous segments. The hard segments are formed by hydrogen bonding between the urethane segments of each polymer chain. While not wishing to be bound by a particular theory, it is believed that the urethane segments of each polymer chain are particularly susceptible to hydrogen bonding with other urethane segments in adjacent polymer chains. Therefore, during the formation of the foam, the urethane segments of each polymer chain hydrogen bond with the urethane segments of other polymer chains contained in the foam, thereby aligning with them. Since the urethane segments of each polymer chain are aligned with the urethane segments of other polymer chains, the polyetherester segments of each polymer chain must align with the polyetherester segments of other polymer chains contained in the foam. This alignment of these polyetherester segments forms the soft segments of the foam. Therefore, due to the hydrogen bonding between the urethane segments of each polymer chain, the foam exhibits a highly ordered three-dimensional network structure of hard and soft segments.

[0072] The polyurethane foam of this example includes crystalline segments formed by hydrogen bonding. In addition, it is believed that the crystalline segments comprising the reaction product of 1,4-butanediol and 1,4-diisocyanatobutane and the amorphous segments comprising poly(ethylene glycol) are formed to alternately construct "stacked" crystalline segments and amorphous segments to provide a 3-dimensional porous structure strengthened by hydrogen bonding between the stacked crystalline segments. In addition, the polyurethane foam of this example easily interacts with other polymers for hydrogen bonding because it includes crystalline segments comprising the reaction product of 1,4-butanediol and 1,4-diisocyanatobutane and the amorphous segments comprising poly(ethylene glycol). Therefore, the flexible film layer 40 can be selected from a polymer such as polyurethane or silicone resin, so that the flexible film layer 40 and the flexible foam layer 38 are bonded to each other by hydrogen bonding and there is substantially no covalent bond between them. In this example, hydrogen bonding readily occurs between the phase-separated polymer, comprising crystalline segments comprising the reaction product of 1,4-butanediol and 1,4-diisocyanatobutane, and amorphous segments comprising poly(ethylene glycol), and the flexible film layer 40 comprising silanol groups and / or urethane groups. The hydrogen bonding between the flexible foam and film layers 38, 40 eliminates the need for an adhesive therebetween. Therefore, in many examples, the bonding interface 24 between the flexible foam and film layers 38, 40 is adhesive-free.

[0073] In one example, removal of the flexible film layer 40 from the flexible foam layer 38 results in cohesive failure of the flexible foam layer 38 at the bonding interface 24. The failure modes exhibited by the flexible film layer 40 when removed from the flexible foam layer 38 can be categorized as adhesive failure, which occurs at the bonding interface 42 between the flexible film layer and the foam layers 38, 40, and cohesive failure, which occurs within the flexible foam layer 38. Thus, cohesive failure can be further described as the area percentage a% of the surface of the flexible film layer 40 and the flexible foam layer 38 to which it is bonded that retains phase-separated polymer (foam) when the flexible film layer 40 is peeled from the flexible foam layer 40. Thus, in some examples, the cohesive failure between the flexible film layer 40 and the flexible foam layer 38 is greater than 50, 60, 70, 80, 90, or 95%. Alternatively, cohesive failure is described as from 50 to 99%, from 50 to 96%, from 60 to 96%, from 70 to 96%, from 80 to 93%, from 80 to 90%, from 80 to 87%, from 80 to 84%, from 83 to 99%, from 85 to 99%, from 89 to 99%, from 92 to 99%, from 95 to 99%, from 83 to 96%, from 86 to 93%, from 92 to 98%, from 95 to 98%, or 90%. Removal of the flexible film layer 40 from the flexible foam layer 38 can be achieved manually (by manually peeling the flexible film layer 40 from the flexible foam layer 38) or according to a standardized test method, such as ASTM D3330 or ASTM D903.

[0074] The active agent can be dispersed within the flexible foam layer 38, and more specifically, dispersed within the phase-separating polymer. Typically, the active agent is a drug (i.e., any pharmaceutically active compound), an antibiotic, an anti-inflammatory agent, a corticosteroid, a hemostatic agent, an anti-allergen, an anticholinergic agent, an antihistamine, an anti-infective agent, an antiplatelet agent, an anticoagulant, an antithrombotic agent, an anti-scarring agent, an anti-proliferative agent, a chemotherapeutic agent, an anti-tumor agent, a healing agent, a decongestant, a vitamin, a hypertonic agent, an immunomodulator, an immunosuppressant, or a combination thereof.

[0075] The active agent can be located in the cell walls of the foamed phase separation polymer. Alternatively, the active agent can be located in the voids of the foamed phase separation polymer. When the drug is located in the cell walls of the pores, the porosity of the specific drug containing the foaming portion affects the release rate of the active agent. The higher the porosity, the higher the release rate, and vice versa. Without wishing to be bound by theory, it is believed that increased porosity leads to an increased degradation rate of the phase separation polymer and thus increases the release rate. In other words, the degradation of the phase separation polymer controls the release of the active agent.

[0076] The release rate of the active agent from the phase-separated polymer can be expressed as the time required to release a certain amount of drug within a certain period of time. Typically, it takes 8 hours to 1.5 days to release 50% of the active agent from the foam shell portion 14. In certain examples, it may be preferred that 50% of the active agent be released over a longer period of time, such as within 1 to 5 days. In order to release approximately 100% (e.g., greater than 95%) of the active agent, a period of 4 to 14 days is generally preferred.

[0077] In one example, the active agent includes a molecule comprising at least one hydrogen atom, which is bound to a nitrogen, oxygen, or fluorine atom. This structure facilitates hydrogen bonding between the active agent and the phase separation polymer, for example, a polyurethane foam comprising a crystalline segment comprising a reaction product of 1,4-butanediol and 1,4-diisocyanatobutane and an amorphous segment comprising poly(ethylene glycol). In other words, the active agent may advantageously include a polymer comprising hydrogen atoms that can be used to form hydrogen bonds with the crystalline segments of the first and / or second polyurethane foams. The hydrogen bonding between the active agent and the phase separation polymer helps to control and slow the release of the active agent.

[0078] In one example, the active agent is a steroidal anti-inflammatory agent. It has been found that the relatively slow release of the active agent from the phase separation polymer is particularly suitable for steroidal anti-inflammatory agents, such as corticosteroids. In another example, the active agent is a hemostatic agent. Of course, the closure device 10 can include both an anti-inflammatory agent (such as a steroid) and a hemostatic agent. In various examples, the hemostatic agent includes at least one hydrogen atom bonded to a nitrogen atom, and / or at least one hydrogen atom bonded to an oxygen atom, wherein the hydrogen atom can be used to form hydrogen bonds with the crystalline segments of the first and / or second polyurethane foam. In such an example, the molecules of the hemostatic agent and the molecules of the phase separation polymer are bonded to each other by hydrogen bonds and there is substantially no covalent bond between them.

[0079] In some examples, the hemostatic agent is a chitosan hemostatic agent. As used herein, the term "chitosan hemostatic agent" refers to chitosan or a salt or derivative thereof. Good results have been obtained using chitosan or chitosan acetate. Chitosan is a polysaccharide comprising D-glucosamine units (deacetylated units) and N-acetyl-D-glucosamine units (acetylated units). Chitosan can be prepared from chitin by deacetylation of at least a portion of the N-acetyl-D-glucosamine in chitin (poly-N-acetyl-D-glucosamine) by hydrolysis. The ratio of D-glucosamine units to N-acetyl-D-glucosamine units in chitosan is typically expressed as the degree of deacetylation. The degree of deacetylation is defined as the percentage of deacetylated glucosamine units in the chitosan. Therefore, this percentage corresponds to the molar percentage of deacetylated units present in the chitosan.

[0080] Without being bound by theory, it is believed that a higher degree of deacetylation improves hemostatic properties. Chitosan can have a degree of deacetylation of 1-100 % by mole, 25-100 % by mole, 50-100 % by mole, 75-100 % by mole, 85-100 % by mole, 90-100 % by mole, 5-50 % by mole, 10-35 % by mole or 10-25 % by mole. The above values ​​are also applicable to chitosan present in chitosan salts, and chitosan derivatives (which have acetylated and deacetylated units, just like chitosan itself). In other non-limiting examples, all values ​​and value ranges within and including the above range endpoints are clearly considered at this. Without being bound by theory, it is believed that a higher degree of deacetylation improves the hemostatic properties of chitosan.

[0081] Suitable chitosan salts are those in which the chitosan ions have a net positive charge. Thus, suitable chitosan salts can be salts composed of chitosan cations and counter anions. For example, chitosan hemostatic agents can be salts of chitosan with organic acids, particularly carboxylic acids such as succinic acid, lactic acid, or glutamic acid. Chitosan salts can, for example, be selected from the group consisting of nitrates, phosphates, glutamates, lactates, citrates, acetates, and hydrochlorides of chitosan. Typically, chitosan derivatives are chitosan molecules in which one or more hydroxyl and / or amine groups present in the chitosan have been substituted. For example, one or more hydroxyl groups can be substituted to obtain ethers or esters. Amine groups can be substituted to obtain amino groups, although this generally results in a reduction in hemostatic activity. Therefore, the amine groups of chitosan are typically unsubstituted. Chitosan hemostatic agents can include or be derived from chitosan derived from animals, plants, or shellfish. These sources have given similarly good results in terms of the above-mentioned hemostatic effects. In addition, synthetic chitosan can also be used. Other examples of suitable chitosan salts are chitosan esters of glutamic acid, succinic acid, phthalic acid or lactic acid, chitosan derivatives containing one or more carboxymethylcellulose groups, carboxymethyl chitosan. Other suitable examples of chitosan derivatives are chitosans with quaternary groups (e.g., N-trimethylene chloride, N-trimethyleneammonium). In addition, biologically active excipients such as calcitonin or 5-methylpyrrolidinone can be used. The molecular weight of the chitosan hemostatic agent can be about 1-1000 kDa, 1-500 kDa, 1-250 kDa, 1-100 kDa, 10-1000 kDa, 10-500 kDa, 10-250 kDa, 10-100 kDa, 30-80 kDa, 50-1000 kDa, 50-500 kDa, 50-350 kDa, 50-250 kDa, 100-1000 kDa, 100 kDa, 100-250 kDa, 150-500 kDa, 200-1000 kDa, 200-750 kDa, 200-500 kDa, 225-275 kDa, 200-300 kDa, 210-390 kDa, 90-1000 kDa, 190-1000 kDa, 290-1000 kDa, or 390-1000 kDa. In additional non-limiting examples, all values ​​and ranges of values ​​within and including the aforementioned range endpoints are expressly contemplated herein.

[0082] In certain examples, when the active agent is a hemostatic agent, the foamed portion (ie, the foamed shell portion and / or the foamed core portion) comprising the hemostatic agent has a porosity of 85-99% and a viscosity of 0.03-0.07 g / cm 3 These values ​​of porosity and density help enhance hemostatic activity and also provide a foam with good liquid (e.g., water or blood) absorption properties. Alternatively, the foamed portion has a porosity of 0.03-0.07 g / cm 3 The foam may have a foam density of 92-98% or a porosity of 95-98%. The amount of hemostatic agent may be at least 0.1 wt.%, preferably at least 2 wt.%, and more preferably at least 5 wt.%, of the total weight of the foam portion containing the hemostatic agent. It is noteworthy that even this relatively small amount of hemostatic agent is sufficient to provide the desired hemostatic properties to the foam nasal dressing. Furthermore, the amount of hemostatic agent is typically less than 99 wt.%, less than 50 wt.%, or less than 35 wt.%, of the total weight of the foam portion. Since the hemostatic activity of the foam nasal dressing is largely independent of the hemostatic agent, high concentrations are generally neither necessary nor preferred. The hemostatic agent is preferably present in the foam in the form of particles, particularly polymer particles. Examples of suitable particles are amorphous, crystalline, and gel-like particles. The hemostatic agent may also be a liquid, particularly when highly viscous. In the case of hemostatic particles, the particles may have a size of 1-1000 μm. Preferably, the particles are less than 150 μm. In particular, better results are achieved using particles of 5-90 μm. Small particles have many advantages. First, the presence of small particles has less of an impact on the foam structure than large particles. Second, small hemostatic particles have a lesser tendency to aggregate than large particles. Furthermore, the use of small particles allows for better dispersion. Finally, small particles do not settle during foam preparation, allowing for uniform distribution within the foam if desired. The hemostatic particles can have any suitable shape, but are preferably approximately spherical. The particles are preferably solid. Suitable solid particles for use are generally insoluble and hydrophilic.

[0083] Alternatively, one or more portions of the flexible foam layer 38 may be free of active agents. The various portions / films of the flexible foam layer 38 may comprise an active agent or drug, be substantially free of a drug, or be free of a drug, respectively. The term "substantially free," as used with reference to any of the active agents or drugs described herein, may be defined as less than 5, 4, 3, 2, 1, 0.5, 0.1, 0.05, or 0.01 wt.% based on the total weight of the particular portion or based on the total weight of the flexible foam layer 38. The present disclosure contemplates that "substantially free" also includes "free." Thus, when a portion and / or device 10 is described as being "substantially free" of something (e.g., a drug), the descriptive language may be narrowed to "free."

[0084] The polymer of flexible membrane layer 40 can comprise polysiloxane or polyurethane, or the bioabsorbable polymer comprising silanol group and / or urethane group.In other variants, flexible membrane layer 40 is non-biodegradable, for example medical grade organosilicon elastomer film.A kind of such organosilicon elastomer film suitable for the present application is sold with the trade name SILPURAN owned by Wacker Chemie AG (Munich, Germany).The term "biodegradable" as used herein refers to the ability of polymer to be acted on biochemically by living cells, organisms or a part of these systems, including hydrolysis, and degradation and decomposition into chemical or biochemical products.In addition, the term "bioresorbable" as used herein refers to the ability to be completely metabolized by the human or animal body.

[0085] A particularly advantageous embodiment includes a bioresorbable flexible foam layer 38 and a biocompatible and non-biodegradable flexible film layer 40. The stent 32 may be placed in the patient's body and remain in place for several weeks or months. The non-biodegradable flexible film layer 40 remains intact, while the bioresorbable flexible foam layer 38 absorbs after a period of time. Before, during, and after the absorption period, the frontal sinus remains open due to the resilience of the flexible film layer 40. At the same time, the active agent within the flexible foam layer 38 is delivered to the frontal sinus to facilitate an optimal wound recovery environment. For example, local administration of corticosteroids can be achieved while mechanically maintaining the patency of the frontal sinus. Once the stent 32 needs to be removed, the flexible film layer 40 is the main or entirely retained component, forming a more streamlined structure for easy removal through the nasal passages.

[0086] As described above, the stent 32 is deployed from the cartridge 36. Referring now to Figure 9-14 The barrel 36 includes a sheath 76 having at least one sidewall 78. The sheath 76 can be tubular in form, such that the sidewall 78 defines a lumen 80. The sidewall 78 includes a distal end 82 opposite a proximal end 84, with the lumen 80 extending between the distal and proximal ends 82, 84. The lumen 80 can define a volume sized to receive substantially the entirety of the rolled stent 32, more specifically, between the distal and proximal ends 82, 84. The sheath 76 can be flexible so as to conform to the contours of the anatomy of the frontal sinus when the sheath is inserted therein, thereby reducing the possibility of injury.

[0087] Cartridge 36 includes a cap portion 86 coupled to sheath 76 . Figure 9-14 The cap portion 86 is shown coupled to the proximal end 84 of the sheath 76. The cap portion 86 includes a cap body 88, a lip 90, and a coupling feature 92. The cap body 88 defines an aperture 94 that communicates with the lumen 80 of the sheath 76. The aperture 94 of the cap body 88 can be coaxial with the lumen 80 of the sheath 76, and the diameters of the lumen 80 of the sheath 76 and the aperture 94 of the cap body 88 can each be substantially equal. The lip 90 extends outwardly from the cap body 88. Figure 9-14 The lip 90 is annularly arranged around the cap body 88 having a cylindrical profile. The coupling feature 92 is provided on the cap body 88. Figure 13 As best shown, the coupling feature 92 may include deflectable fingers spaced circumferentially around the cylindrically contoured cap 88. In a manner to be further explained, the aperture 94, the lip 90, and the coupling feature 92 cooperate to removably couple the cartridge 36 to the applicator device 34. The coupling feature may be implemented in alternative manners, such as notches, grooves, threads, etc. The cartridge 36 may be a disposable component of the system 30.

[0088] The cartridge 36 is configured to removably receive the stent 32 either before or after coupling with the applicator device 34. In one example, the stent 32 is pre-loaded within the sheath 76 of the cartridge 36. Figure 9-11 The bracket 32 ​​( Figure 4B 32b) is loaded into certain steps in the barrel 36. The bracket 32b is shown as being in a state of expansion or unrestricted. The bracket 32b can be manually rolled up to present a roughly cylindrical profile. The first body portion 60 and the second body portion 62 can be rolled up independently except at the joint 64, or can be manipulated to roll up as a unit. When rolled up, the flexible foam layer 40 at least partially defines the outer annular level 56 of the bracket 32b, as shown in the figure, and the flexible membrane layer 38 at least partially defines the inner annular level 58 of the bracket 32b. The rolled bracket 32b can be inserted into the barrel 36 and guided through the inner cavity 80 so that the lower end 48 is guided through the orifice 94 of the cap portion 86 to be roughly aligned with the base of the cap portion 86. Figure 11 86. The lower end 48 of the inner annular layer 58 is best shown at or near the base of the cap portion 86. Due to the resiliency of the flexible membrane layer 40, it will be appreciated that the stent 32b can be slightly expanded within the lumen 80, subject to the constraint provided by the sheath 76. With the slight expansion within the sheath 76, the internal passage 57 can become slightly more unobstructed. The rolled stent 32 within the barrel 36 can be considered a barrel assembly. It should be understood that various types of stents can be used in the barrel, and the systems and methods described herein can be used to place the stent and / or barrel in locations other than the frontal sinus, including, but not limited to, other sinus spaces, intravenously, in arthroscopic surgery, in nerve repair, in joints, and in various ear and throat applications.

[0089] Now refer to Figure 1-3 and Figure 12-14, the applicator device 34 includes a housing 96 defining an aperture 100. The housing 96 may include a distal housing portion 102 coupled to a proximal housing portion 104, wherein the aperture 100 extends through at least a portion of each of the distal and proximal housing portions 102, 104. The housing 96 is configured to be removably coupled with the barrel 36. In particular, the distal housing portion 102 may include a head 105 near the distal end of the distal housing portion 102. The head 105 defines an opening 106 in communication with the aperture 100. Near the opening 106, the head 105 includes a coupling feature 108 that is complementary to the coupling feature 92 of the cap portion 86 of the barrel 36. Figure 13 The coupling feature 108 is best shown as a keyway disposed circumferentially about the head 105, which is positioned to complement the circumferential location of the key comprising the coupling feature 92. In addition, the opening 106 is sized to slidably and snugly receive the cap body 88 of the cap portion 86. With particular reference to Figure 13 and 14 , the cap 88 is guided through the opening 106 until the lip 90 abuts the distal end of the applicator device 34. Simultaneously or subsequently, the rotational orientation of the barrel 36 relative to the applicator device 34 is arranged so that the complementary coupling features 92, 108 are aligned and engaged, thereby selectively coupling the barrel 36 and the applicator device 34.

[0090] The rolled stent 32 can be inserted into the sheath 76 of the barrel 36 before the cap portion 86 is removably coupled to the applicator device 34. The applicator device 34 includes a drive member 110 and a plunger element 112 coupled to the drive member 110. The drive member 110 may include a spindle 114 extending distally of the plunger element 112. Figure 3 、 12 As will be appreciated from Figure 13, when the stent 32 is disposed within the barrel 36 and the barrel 36 is coupled to the applicator device 34, the mandrel 114 extends through the passage 57 defined by the inner annular layer 58 of the stent 32. In particular, the aperture 94 of the cap portion 86 and the lumen 80 of the sheath 76 are sized to receive the mandrel 114 of the applicator device 34. Furthermore, as described above, the internal passage 57 can become slightly more open with slight unrolling within the sheath 76. Thus, the user aligns the distal tip 116 of the mandrel 114 with the internal passage 57 rolled up within the barrel 36. As previously described, the user guides the mandrel 114 through the internal passage 57 until the lip 90 abuts the distal end of the applicator device 34 and the complementary coupling features 92, 108 are engaged. The mandrel 114 can provide control over the positioning of the stent 32 within the frontal sinus during deployment of the stent 32 from the barrel 36.

[0091] Figure 1-3The housing 96 is shown and is configured to be grasped by a user, for example, with one hand. In particular, the housing 96 can include a handle 118 extending laterally outward from the proximal housing portion 104, wherein the handle 118 is contoured to be manipulated by the fingers of a single hand of a user. The applicator device 34 also includes an actuator 120 coupled to the drive member 110, more specifically to the proximal end of the drive member 110 extending through the aperture 100. Continued reference Figure 2 and Figure 3 , the actuator 120 may include a push rod 122 snugly and slidably disposed within the bore 100 of the proximal housing portion 104, and a control surface 124 coupled to the push rod 122. The control surface 124 is configured to receive input from a user to move the push rod 122 relative to the housing 96. In particular, the control surface 124 is sized and positioned to maintain its position when the user provides input to the handle 118 to retract the proximal housing portion 104 relative to the actuator 120. Additionally or alternatively, the user may advance the push rod 122 while maintaining the position of the proximal housing portion 104. The relative movement of the push rod 122 relative to the housing 96 causes the drive member 110 to move relative to the housing 96.

[0092] As described above, the push rod 122 abuts the proximal end of the drive member 110. The drive member 110 may include a proximal portion 126 and a distal portion 128 positioned distal to the proximal portion 126. The proximal and distal portions 126, 128 of the drive member 110 may be separate components coupled to one another, or may have a unitary structure. The proximal portion 126 may be substantially rigid, while the distal portion 128 may be flexible relative to the proximal portion 126. For example, the distal portion 128 (and at least the corresponding overlapping length of the distal housing portion 102) may be malleable to allow a user to apply a force to impart a desired curve to the applicator device 34. Additionally or alternatively, the distal portion 128 of the drive member 110 may be malleable and the corresponding overlapping length of the distal housing portion 102 may be flexible to impart the desired curve to the applicator device 34. Advantageously, imparting a desired curve to the applicator device 34 may allow the user to access more distal anatomical structures of the frontal sinus.

[0093] Figure 3The plunger element 112 is shown as an annular flange extending from the drive member 110. A spindle 114 can extend distally from the plunger element 112. The aperture 94 of the cap portion 86 of the barrel 36 is sized to receive the plunger element 112 when the cap portion 86 is coupled to the housing 96 of the applicator device 34. More specifically, the inner diameter of the aperture 94 is larger than the outer diameter of the plunger element 112 such that the plunger element 112 can pass through the aperture 94 upon actuation of the applicator device 34. Likewise, the lumen 80 of the sheath 76 of the barrel 36 is larger than the outer diameter of the plunger element 112 such that the plunger element 112 can pass through the lumen 80 upon actuation of the applicator device 34 when the stent 32 is deployed from the sheath 76. Further Reference Figure 15 and 16 , Figure 3 and 15 18 and 19. The barrel 36 is shown coupled to the applicator device 34 with the rolled stent 32 disposed within the barrel 36. The mandrel 114 extends through the interior passage 57 of the rolled stent 32 with the distal tip 116 of the mandrel 114 proximate the distal end 82 of the sheath 76. The distal housing portion 102 and the distal portion 128 of the drive member 110 are in a bent configuration. The user holds the applicator device 34, for example, in one hand with a finger on the handle 118 and a thumb on the control surface 124 of the actuator 120. When the stent 32 is ready to be deployed, an input (e.g., a squeezing motion) is provided to one or both of the handle 118 and the control surface 124 to cause the housing 96 to move relative to the actuator 120 along the barrel 36. Figure 15 128 of the drive member 110. As shown, the housing 96 moves toward the control surface 124, and more specifically, the distal housing portion 102 is retracted proximally relative to the drive member 110. Due to the flexible nature of the distal housing portion 102 and the compliant nature of the distal portion 128 of the drive member 110, the distal housing portion 102 straightens to conform to the shape of the proximal portion 126 of the drive member 110 during retraction.

[0094] The barrel 36 and the distal housing portion 102 are coupled to each other by complementary coupling features 92, 108, and the plunger element 112 supports the lower end 48 of the bracket 32. In addition, as described above, the aperture 94 of the cap portion 86 is sized to allow the plunger element 112 to pass therethrough. As such, retraction of the distal housing portion 102 causes the barrel 36 to retract on the drive member 110, as shown. Figure 16 As shown, the flexible nature of the sheath 76 of the barrel 36 allows the barrel 36 to conform to the curve imparted by the drive member 110. The stent 32 is constrained by the plunger element 112 from moving in a corresponding manner, and the stent 32 is exposed outside the barrel 36, thereby deploying the stent 32. The stent 32 in the unconstrained state is expanded in the manner previously described.

[0095] Will refer to Figure 17The anatomical structure of the frontal sinus (FS) is described as follows: an exemplary method of using the system 30. The frontal sinus (FS) includes a frontal sinus cavity (FSC) that leads to the nasal passage (NP) through the frontal sinus opening (FSO) (i.e., the mouth). The nasal passage (NP) is at least partially defined by the superior turbinate (ST), the middle turbinate (MT), and the inferior turbinate (IT), which are used to heat, humidify, and filter air. The sinuses also include the maxillary sinus cavity (MSC) and the ethmoid sinus (ES), etc. The frontal sinus cavity, the nasal passage, the maxillary sinus cavity, etc. are defined by the mucosal wall (MW). If the mucosal wall defines the frontal sinus opening, it is particularly interesting. The system 30 is provided as including a stent 32, an applicator device 34, and a barrel 36. The stent 32 can be pre-loaded in the barrel 36 (e.g., airtightly sealed with a membrane cover). Alternatively, the stent 32 can be changed to a desired contour, for example, by cutting the incision 68 of the stent 32 into a desired shape. The stent 32 is manually rolled up and loaded into the sheath 76 of the barrel 36. The flexible membrane layer 40 at least partially defines the inner annular layer 58 of the stent 32, and the flexible foam layer 38 at least partially defines the outer annular layer 56 of the stent 32. The distal end 82 of the sheath 76 is introduced into and through the nasal passage, as shown. Figure 17 As shown. The distal end 82 of the sheath 76 can be guided through the frontal sinus opening and positioned slightly above the frontal sinus opening. An input is provided to the applicator device 34 to retract the barrel 36 relative to the drive member 110 to deploy the stent 32. The first body portion 60 of the stent 32 can be positioned in the frontal sinus cavity, and the second body portion 62 can be positioned in the frontal sinus opening and / or the nasal passage. Because the front and second body portions 60, 62 can be deployed independently, the first body portion 60 is deployed to a relatively large extent to interfere with the anatomical structures defining the frontal sinus cavity near the frontal sinus opening. This interference helps to keep the stent 32 within the frontal sinus. The second body portion 62 is deployed to form and maintain the patency of the frontal sinus opening. In addition, the flexible foam layer 38, which is in direct contact with the mucosal wall, can deliver the active agent. The applicator device 34 is removed from the frontal sinus, and the barrel 36 is separated from the applicator device 34 and disposed of in an appropriate manner. It is also contemplated that the stent can be pre-loaded in the barrel, and both the stent and the barrel are packaged together under a sterile condition.

[0096] As will be readily appreciated, system 30 is well-suited for deploying stent 32 to maintain patency of the frontal sinus ostium. It is contemplated that system 30 may be used to deploy stent 32 within any sinus ostium or passage, including those communicating with the ethmoid, sphenoid, maxillary sinuses, or passages defined by the superior, middle, and / or inferior nasal conchae. It is also contemplated that system 30 may be used in other passages, and that system 30 may be used to deploy stent 32 within other ostiums and passages of the nose, ear, throat, brain, and the like.

[0097] Certain embodiments may be described with reference to the following exemplary terms:

[0098] Item 1 - A method for positioning a stent within a frontal sinus cavity of a patient using a system comprising an applicator device, the applicator device comprising a housing, an actuator, and a drive member coupled to the actuator, the system further comprising a disposable cartridge comprising a tubular sheath and a cap portion coupled to the tubular sheath, the stent comprising a flexible foam layer having a porosity greater than 80%, and a flexible membrane layer, the method comprising: removably coupling the cap portion of the disposable cartridge to a distal end of the applicator device while the stent is rolled and assumes a substantially circular shape within the tubular sheath. a cylindrical profile, wherein the flexible foam layer at least partially defines an outer annular layer of the stent, and the flexible membrane layer is resiliently deformed and at least partially defines an inner annular layer of the stent; positioning the distal end of the tubular sheath near or within the frontal sinus cavity; and providing input to one or both of the housing and the actuator to move the tubular sheath relative to the drive member to expel the stent from the tubular sheath into the frontal sinus cavity, so that the flexible membrane layer resiliently expands the flexible membrane layer and the flexible foam layer to cause the outer annular layer of the flexible foam layer to directly contact the mucosa of the frontal sinus cavity.

[0099] Clause 2 - A method according to clause 1, wherein each of the applicator device and the disposable barrel includes complementary coupling features, the method further comprising aligning and engaging the complementary coupling features to position the tubular sheath having the rolled-up stent disposed therein adjacent to a drive member of the applicator device.

[0100] Clause 3 - The method of clause 1 or 2, wherein the cap portion includes an annular lip, the method further comprising positioning the annular lip against the distal end of the applicator device, wherein complementary coupling features engage.

[0101] Clause 4 - A method according to any one of clauses 1-3, wherein the bracket further comprises a first body portion and a second body portion, wherein the first body portion and the second body portion are connected at a joint extending partially between opposite sides of the bracket, such that the first body portion and the second body portion are configured to be independently rolled up and / or unfolded other than at the joint, and the method further comprises cutting the bracket to provide a cut extending inwardly from opposite sides of the bracket, wherein the cut defines the first body portion and the second body portion.

[0102] Clause 5 - The method of Clause 4, wherein the stent further comprises a slit extending inwardly from opposing sides of the stent to define the first body portion and the second body portion, the method further comprising cutting the stent to modify the slit to provide the cutout.

[0103] Clause 6 - The method of any of Clauses 1-5, further comprising disposing the first body portion within the frontal sinus cavity and positioning the second body portion through the frontal sinus opening.

[0104] Clause 7 - A method according to any of clauses 1-6, wherein the applicator device comprises a handle and a flexible housing connected to the handle, and wherein at least a portion of the drive member is compliant, the method further comprising providing input to the drive member to impart a desired curve to the disposable cartridge relative to the housing.

[0105] Clause 8 - The method of any of Clauses 1-7, further comprising manually rolling up the stent; and inserting the rolled stent into the tubular sheath of the disposable cartridge prior to the step of removably coupling the cap portion to the applicator device.

[0106] Clause 9 - The method of any of clauses 1 -8, wherein the stent is pre-loaded within the tubular sheath of the disposable cartridge.

[0107] Clause 10 - A method according to any one of clauses 1-9, wherein when the rolled stent is disposed within the tubular sheath, the inner annular layer of the rolled stent defines an internal channel, and wherein the step of connecting the cap portion of the disposable barrel to the distal end of the applicator device further comprises guiding a spindle extending from the distal end of the drive member through the internal channel of the rolled stent.

[0108] Clause 11 - The method of any of Clauses 1-10, further comprising: separating the cap portion from the distal end of the applicator device; and disposing of the disposable cartridge.

[0109] Clause 12 - A method according to any of clauses 1-11, wherein the applicator device includes a housing defining an aperture, and a handle coupled to the housing, wherein the step of actuating an actuator of the applicator device further comprises providing an input to the handle while maintaining a position of the actuator to retract the housing relative to the drive member such that the stent is expelled from the tubular sheath.

[0110] Item 13 - A method according to item 12, wherein the cap portion of the disposable cartridge defines an orifice sized to movably receive a drive member, wherein the step of providing input to the handle to retract the housing relative to the drive member further includes guiding the drive member through the orifice of the cap portion and the tubular sheath.

[0111] Several examples have been discussed in the preceding description. However, the examples discussed herein are not intended to be exhaustive or to limit the invention to any particular form. The terminology used is intended to be descriptive rather than restrictive. Many modifications and variations are possible in light of the above teachings, and the invention may be practiced in ways other than those specifically described.

Claims

1. A stent positionable in a frontal sinus cavity, the stent comprising: A flexible foam layer having a porosity greater than 80%, the flexible foam layer comprising polyurethane, the polyurethane comprising amorphous segments and crystalline segments formed by hydrogen bonding; an active agent within the flexible foam layer; and a flexible membrane layer arranged in a stacked configuration and comprising a polymer structured to form hydrogen bonds with crystalline segments of the flexible foam layer at a bonding interface, wherein the flexible foam layer and the flexible membrane layer are configured to be rolled to assume a cylindrical profile prior to insertion into the frontal sinus cavity, such that the flexible foam layer at least partially defines an outer annular layer of the stent and the flexible membrane layer at least partially defines an inner annular layer of the stent, The flexible membrane layer has a restoring force sufficient to unfold the stent and cause the outer annular layer of the flexible foam layer to directly contact the mucosa of the frontal sinus cavity when the stent is positioned in an unrestricted state in the frontal sinus cavity. 2 . The stent of claim 1 , wherein removing the flexible film layer from the flexible foam layer results in cohesive failure of the foam layer at the bonding interface. 3 . The stent of claim 1 , wherein the bonding interface is free of adhesive and the flexible membrane layer and the flexible foam layer are directly bonded to each other by hydrogen bonding. The stent of claim 1 , wherein there is no covalent bond between the flexible film layer and the flexible foam layer.

5. The stent of claim 1 or 4, wherein the crystalline segments of the flexible foam layer comprise the reaction product of 1,4-butanediol and 1,4-diisocyanatobutane.

6. The stent of claim 1 or 4, wherein the molecules within the flexible foam layer are arranged such that the crystalline segments and the amorphous segments are stacked in an alternating configuration to provide a 3-dimensional porous structure, which is strengthened by hydrogen bonding between the stacked crystalline segments.

7. The bracket according to claim 1 or 4 further includes a first body portion and a second body portion, wherein the first body portion and the second body portion are connected at a joint extending partially between opposite sides of the bracket, so that the first body portion and the second body portion are configured to be rolled up and / or unfolded independently except at the joint, and wherein each of the first body portion and the second body portion includes the flexible foam layer and the flexible membrane layer.

8. A bracket according to claim 7, wherein the first body portion and the second body portion are separated at a boundary defined between the opposite sides and including the joint, wherein the bracket also includes a cutout extending inward from the opposite sides, the cutout including a first level associated with the first body portion and a second level associated with the second body portion, wherein each of the first level and the second level of the cutout is inclined at an angle relative to the boundary.

9. The stent of claim 8, wherein an angle of the first plane of the cutout relative to the boundary is within a range of 25 degrees and 75 degrees.

10. The stent of claim 8, wherein an angle of the second level of the cutout relative to the boundary is within a range of 25 degrees and 75 degrees. The stent according to claim 8 , wherein the first layer and the second layer are continuous with each other and form a parabolic-shaped cutout.

12. The bracket of claim 8, wherein the flexible foam layer includes a first thickness defined between a first outer surface and the interface, and the flexible membrane layer includes a second thickness defined between a second outer surface opposite the first outer surface and the bonding interface, wherein the first thickness is greater than the second thickness.

13. The bracket according to claim 8, wherein the opposite sides are first opposite sides, and the bracket further includes second opposite sides extending between the first opposite sides, the second opposite sides are arcuate in shape and intersect with the first opposite sides at rounded corners.

14. The stent of claim 1 or 4, wherein the flexible membrane layer comprises polysiloxane.

15. The stent of claim 1 or 4, wherein the flexible membrane layer comprises polyurethane.

16. The stent according to claim 1 or 4, wherein the flexible membrane layer comprises a bioabsorbable polymer containing silanol groups and / or urethane groups.

17. The stent of claim 1 or 4, wherein the flexible foam layer is bioabsorbable.

18. The stent of claim 1 or 4, wherein the active agent comprises a molecule comprising at least one hydrogen atom bound to a nitrogen, oxygen, or fluorine atom.

19. The stent of claim 1 or 4, wherein the active agent is selected from the group consisting of corticosteroids, hemostatic agents, and combinations thereof.

20. A disposable cartridge for use with an applicator device to deploy a stent within a frontal sinus cavity, the disposable cartridge comprising: A bracket, comprising: A flexible foam layer having a porosity greater than 80%, the flexible foam layer comprising polyurethane, the polyurethane comprising amorphous segments and crystalline segments formed by hydrogen bonding; an active agent within the flexible foam layer; and a flexible membrane layer arranged in a stacked configuration and comprising a polymer structured to hydrogen bond with crystalline segments of the flexible foam layer at a bonding interface, wherein the flexible foam layer and the flexible membrane layer are configured to be rolled to assume a cylindrical profile prior to insertion into the frontal sinus cavity such that the flexible foam layer at least partially defines an outer annular aspect of the stent and the flexible membrane layer at least partially defines an inner annular aspect of the stent, wherein the flexible membrane layer has a restoring force sufficient to deploy the stent when positioned in an unrestrained state in the frontal sinus cavity; a tubular sheath comprising at least one sidewall defining a proximal end, a distal end opposite the proximal end, and an interior lumen extending between the proximal and distal ends and defining a sheath volume sized to receive the entire rolled stent therebetween; a cap portion coupled to the proximal end of the tubular sheath and comprising: a cap defining an aperture in communication with the lumen of the tubular sheath, the aperture sized to receive a plunger element of an applicator device; a lip extending outwardly from the cap to define a surface configured to abut a distal end of the applicator device when the disposable cartridge is coupled with the applicator device; and A coupling feature is provided on the cap, wherein the coupling feature is configured to removably engage a complementary coupling feature of the applicator device.

21. The disposable cartridge of claim 20, wherein the tubular sheath is flexible and sized for insertion into the frontal sinus cavity.

22. The disposable cartridge according to claim 20 or 21, wherein the lip is arranged annularly around the cap body, having a cylindrical profile.

23. The disposable cartridge according to claim 20 or 21, wherein the aperture of the cap is coaxial with the lumen of the tubular sheath.

24. The disposable cartridge according to claim 20 or 21, wherein The inner cavity of the tubular sheath and the orifice of the cap body have corresponding diameters that are equal.

25. The disposable cartridge of claim 20 or 21, wherein the coupling feature comprises deflectable fingers spaced circumferentially around the cap.

26. A system for placing a stent in a frontal sinus cavity, the system comprising: an applicator device comprising a housing defining an aperture and adapted to be grasped by a single hand of a user, an actuator, and a drive member coupled to the actuator, wherein the drive member is configured to move within the aperture in response to one or both of the housing and the actuator receiving an input from the user; a disposable cartridge removably coupled to the housing and comprising a tubular sheath defining an interior lumen, and a cap portion coupled to the tubular sheath and removably coupled to the housing of the applicator device; and A bracket, comprising: A flexible foam layer having a porosity greater than 80%, the flexible foam layer comprising polyurethane, the polyurethane comprising amorphous segments and crystalline segments formed by hydrogen bonding; a flexible film layer arranged in a stacked configuration and comprising a polymer structured to form hydrogen bonds with the crystalline segments of the flexible foam layer at a bonding interface; and an active agent within the flexible foam layer; The stent is configured to be rolled and inserted into the tubular sheath, and the flexible membrane layer has a restoring force sufficient to deploy the stent when positioned in an unrestrained state in the frontal sinus cavity.

27. The system of claim 26, wherein removing the flexible film layer from the flexible foam layer results in cohesive failure of the foam layer at the bonding interface.

28. The system of claim 26, wherein the bonding interface is free of adhesive and the flexible membrane layer and the flexible foam layer are directly bonded to each other by hydrogen bonding.

29. The system of claim 26, wherein the stent assumes a cylindrical profile when rolled up, the flexible foam layer at least partially defining an outer annular layer of the stent and the flexible membrane layer at least partially defining an inner annular layer of the stent.

30. A system according to claim 26, wherein the bracket further includes a first body portion and a second body portion, and the first body portion and the second body portion are connected at a joint extending partially between opposite sides of the bracket, so that the first body portion and the second body portion are configured to be independently rolled up and / or unfolded except at the joint.

31. The system of claim 26, wherein the tubular sheath comprises at least one sidewall defining a proximal end and a distal end opposite the proximal end, an inner lumen extending between the proximal and distal ends and defining a sheath volume, wherein the rolled stent comprises a length defined between the opposite ends, the length being less than a length of the tubular sheath such that the rolled stent is disposed entirely within the sheath volume prior to deployment of the stent from the sheath volume.

32. The system of claim 29, wherein the inner annular layer of the rolled stent defines an internal channel, the drive member comprising a distal end opposite the proximal end coupled to the actuator, and a spindle extending from the distal end and passing through the internal channel of the stent when the stent is disposed within the flexible sheath.

33. The system of claim 32, wherein the cap portion defines an aperture in communication with the lumen of the tubular sheath, wherein a spindle of the drive member extends through the aperture of the cap portion when the cap portion is coupled to the housing.

34. The system of claim 33, wherein the drive member further comprises a plunger element from which the spindle extends, wherein the aperture of the cap portion is sized to receive the plunger element of the applicator device when the cap portion is coupled to the housing.

35. The system of claim 33, wherein the aperture is sized to movably receive the drive member of the applicator device such that the drive member extends through the aperture and the lumen of the tubular sheath when the stent is deployed from the disposable cartridge.

36. The system of claim 26, wherein the housing and the cap portion further comprise complementary coupling features configured for removably coupling the disposable cartridge with the applicator device.

37. A system according to claim 26, wherein at least a portion of the housing is flexible and at least a portion of the drive member is compliant and configured to receive another input from a user, impart a desired curve to the disposable cartridge, and maintain the desired curve of the disposable cartridge relative to the housing upon release of the other input.

38. The system of claim 26, wherein the flexible membrane layer comprises silicone or polyurethane.

39. The system of claim 26, wherein the flexible membrane layer comprises a polymer comprising silanol groups and / or urethane groups.

40. The system of claim 26, wherein the flexible foam layer is bioresorbable.

41. The system of claim 26, wherein the active agent comprises a molecule comprising at least one hydrogen atom bound to a nitrogen, oxygen, or fluorine atom.

42. The system of claim 26, wherein the active agent is selected from the group consisting of corticosteroids, hemostatic agents, and combinations thereof.

43. The system of any one of claims 26-42, wherein there is no covalent bond between the flexible membrane layer and the flexible foam layer.

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