Patent Publication Number: US-11642281-B2

Title: Endoscopic medical device for dispensing materials and method of use

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority from U.S. Provisional Application No. 62/740,242, filed on Oct. 2, 2018, U.S. Provisional Application No. 62/747,863, filed on Oct. 19, 2018, U.S. Provisional Application No. 62/831,900, filed on Apr. 10, 2019, and U.S. Provisional Application No. 62/848,226, filed on May 15, 2019, each of which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to medical systems and devices for delivering pressured fluids, and more particularly, to methods and tools for controlling hemostatic agents and achieving proper tissue contact with the agent at an appropriate pressure and flow rate. 
     BACKGROUND 
     Delivery systems and devices are used to supply various materials, such as powders, during medical procedures. These procedures may include supplying powders using fluids, e.g., propellant fluids, within a range of appropriate pressures and/or flow rates. These powders may include hemostatic agents optimally delivered to tissue at an appropriate pressure and/or flow rate, for the particular application. 
     Conventional endoscope devices for dispensing fluids, powders, and/or reagents in a patient include advancing a catheter to a target site within the patient and subsequently dispensing the fluid. Drawbacks of conventional devices include, for example, clogging of the catheter with the fluid or powder, kinking of the catheter, large variations in the flow rate and pressures of fluids during dispensing, and inconsistency in the material dispensed at the target site. Further, medical fluid delivery systems often require delivering a fluid from a high pressure storage tank to tissue at a lower pressure suitable for the application. The fluid should be applied at a consistent flow rate and at a consistent pressure. In addition, medical fluid delivery systems often require multiple regulators to properly convert the high pressure fluid to a pressure suitable for application to tissue. Multiple regulators inhibit the ability to integrate the regulators with a fluid cylinder, are often costly, and make it difficult to integrate the regulator(s) in a hand-held device for ease of operation. Moreover, conventional regulators include washers or O-rings that generate friction forces with the regulator, making it difficult to dispense fluid at a consistent flow rate and at a consistent pressure. These drawbacks can prevent a proper amount of fluid and/or material from being expelled at a target location, thereby decreasing the accuracy and increasing the time and cost of procedures using these conventional devices. Accordingly, it is desirable to ensure that fluid, powder, and/or reagents are properly and consistently dispensed to the target location. The present disclosure may solve one or more of these problems or other problems in the art. The scope of the disclosure, however, is defined by the attached claims and not the ability to solve a specific problem. 
     SUMMARY OF THE DISCLOSURE 
     According to an example, a medical device includes an application device with a first fluid path and a container movable attached to the application device. The container and the application device have a second fluid path therethrough, the container includes an inner chamber that is intermediate proximal and distal portions of the second fluid path, the inner chamber is fluidly isolated from the distal portion of the second fluid path at a first position of the container, and the inner chamber is fluidly coupled to the proximal and distal portions of the second fluid path at a second position of the container. The first fluid path bypasses the container and the passage of fluid through the first fluid path is separately controllable from the passage of fluid through the second fluid path. 
     The medical device further includes a second container having a propellant fluid and may be configured to be attached to an inlet of the application device. 
     The application device may further include a locking mechanism for securing the second container to the application device. 
     The locking mechanism may include a lever pivotally connected to the application device and a piston connected to the lever and contacting the second container, such that in a first position of the lever, the second container may be fluidly decoupled from the application device, and in a second position of the lever, the second container may be fluidly coupled to the application device. 
     A protrusion may extend from a surface of the piston toward the inlet, and a void may extend into the container from a surface facing the piston. The protrusion may extend into the void to maintain a fixed position of the container with respect to the piston. 
     The container may include a chamber inlet between the inner chamber and the proximal portion of the second fluid path, and a chamber filter, the filter may be configured to allow a fluid to enter the inner chamber from the proximal portion of the second fluid path, and the filter may be configured to prevent a material disposed in the container from entering the proximal portion of the second fluid path. 
     The inner chamber may include one or more protrusions extending from a bottom surface of the inner chamber into the inner chamber, and the one or more protrusions may be configured to change a fluid path of the propellant fluid in the inner chamber. 
     The inner chamber may include a tube having an outlet port, and a sheath disposed about the tube, such that the outlet port may be covered by the sheath when the container is at the first position, and the outlet port ma be exposed from the sheath when the container is at the second position. 
     The inner chamber may include an attachment member fixedly attached to the sheath and an outer surface of the container, and rotation of the outer surface causes the sheath to move longitudinally on the tube. 
     The application device may include includes a groove having a first end and a second end, the container may include a cam extending from the outer surface of the container, the cam may be movable within the groove, wherein the cam may be disposed at the first end of the groove when the container is at the first position, and the cam may be disposed at the second end of the groove when the container is at the second position. 
     The application device may include first and second actuation devices, the first actuation device may be configured to control the propellant fluid in the first fluid path, and the second actuation device my be configured to control the propellant fluid in the second fluid path. 
     The second fluid path may include a pressure release mechanism configured to release fluid when a pressure of a fluid in the second fluid path is greater than a threshold, and the threshold may be greater than a desired pressure of a fluid at an outlet of the second fluid path. 
     The pressure release mechanism may include a burst disc and may be disposed in the inner chamber of the container. 
     The inlet of the application device includes a second pressure release mechanism, and actuation of the second pressure release mechanism may release the propellant fluid from the second container. 
     A catheter may be attached to an outlet of the distal portion of the second fluid path via a luer connection. 
     According to another example, a medical device includes an application device having a first fluid path therethrough, and a container movably attached to the application device, the container and the application device have a second fluid path therethrough, the container has an inner chamber having an inlet configured to be fluidly coupled to a proximal portion of the second fluid path and an outlet configured to be fluidly coupled to a distal portion of the second fluid path, the container includes a filter configured to prevent a material provided in the container from entering the proximal portion of the first fluid path, and the inner chamber is fluidly decoupled from the proximal portion of the second fluid path when the container is at a first position, and the inner chamber is fluidly coupled to the proximal and distal portions of the second fluid path when the container is at a second position. 
     The inner chamber may include a tube having an outlet port, and a sheath disposed about the tube, the outlet port may be covered by the sheath when the container is at the first position, and the outlet port may be exposed from the sheath when the container is at the second position. 
     The application device may include a groove having a first end and a second end, the container may include a cam extending from an outer surface of the container, the cam may be within the groove, the cam may be disposed at the first end of the groove when the container is at the first position, and the cam may be disposed at the second end of the groove when the container is at the second position. 
     According to yet another example, a medical device includes an application device having a first fluid path, an inlet, and an outlet, and a container attached to the application device, the container and the application device have a second fluid path therethrough, the container includes an inner chamber between distal and proximal portions of the second fluid path, the inner chamber includes an inflow configured to be fluidly coupled to the proximal portion of the second fluid path and an outflow configured to be fluidly coupled to the distal portion of the second fluid path, and the inner chamber includes at least one protrusion extending into the inner chamber. Fluid in the first fluid path travels from the inlet to the outlet, bypassing the container, and the second fluid path includes a relief valve configured to release a fluid from the second fluid path when a pressure within the second fluid path is greater than a threshold. 
     The medical device may further include a second container including a propellant fluid, and a locking mechanism, wherein the locking mechanism may include a lever pivotally connected to the application device, a piston connected to the lever and contacting the second container, in a first position of the lever, the second container may be fluidly decoupled from the application device, and in a second position of the lever, the second container may be fluid coupled to the application device. 
     In yet another aspect, a device for regulating pressure of a fluid includes a body having an input opening for receiving the fluid, an output opening for delivering the fluid, and a chamber in fluid communication with and between the input opening and the output opening. The chamber defines a chamber opening, a flexible membrane contacting the body and having a first surface sealingly covering the chamber opening, and a piston adjacent a second surface of the membrane opposite the first surface for regulating a position of the membrane to regulate pressure of the fluid. 
     The device may include a pierce pin within the chamber adjacent the input opening and configured to pierce a seal of a containment device configured to contain the fluid. 
     The body may include a protrusion extending into the chamber and dividing the chamber into a first chamber adjacent the input opening and an annular chamber adjacent the output opening, the device may include an actuator surrounding at least a portion of the protrusion and contacting the first surface of the membrane. 
     The protrusion may include a first hole fluidly connecting the first chamber with the annular chamber, and a prong of the actuator may extend into the first hole. 
     The device may include a first spring disposed in the first chamber and configured to push a ball bearing toward the first hole. 
     The device may include an O-ring provided between the ball bearing and the first hole. 
     A wall of the actuator may include a second hole in fluid communication with and between the annular chamber and the first chamber. 
     The device may include a capture member having a first end attached to the body and a second end defining a capture member chamber in which the piston is movably contained, and a cap may be attached to the capture member adjacent the second end to cover an opening of the capture member. 
     The membrane may be fixed between the body and the capture member. 
     The device may include a second spring disposed between the piston and the cap and configured to force the piston toward the membrane. 
     The annular chamber may not include an O-ring. 
     A fluid path may extend from the input opening, through the first chamber, through the first hole, through the annular chamber, and out the output opening. 
     The device may include an O-ring disposed in the first chamber adjacent to the first hole, a ball bearing may be disposed in the first chamber adjacent the O-ring on a side opposite the first hole, and a spring may be provided in the first chamber contacting the ball bearing and the pierce pin and configured to urge the ball bearing toward the O-ring. 
     The device may include a first hole in the protrusion fluidly connecting the first chamber with the annular chamber, an O-ring may be disposed in the first chamber adjacent to the first hole, and a poppet may include a body portion disposed in the first chamber, having an annular ring surrounding the body and adjacent the O-ring on a side opposite the first hole, and the poppet may include an elongated member extending from the body portion, perpendicular to the annular ring, through the O-ring and a hole, and contacting the body. 
     According to another aspect, a delivery system for dispensing fluid includes a containment device configured to contain the fluid, and an application device connected to the containment device and configured to dispense the fluid, the application device comprising an inlet configured to be connected to the containment device to receive the fluid from the containment device, and a regulator in fluid communication with the inlet and configured to regulate the release of the fluid. The regulator includes a body having an input opening for receiving the fluid, an output opening for delivering the fluid, and a chamber in fluid communication with the input opening and the output opening, the chamber defines a chamber opening, a flexible membrane contacting the body and having a first surface sealingly covering the chamber opening, and a piston adjacent a second surface of the membrane opposite the first surface and configured to regulate a position of the membrane to regulate pressure of the fluid. 
     The system may include a piston chamber defined between and within annular walls of the piston, and a spring may be disposed in the piston chamber and configured to push the piston against the membrane. 
     The system may include an actuating device, and the fluid configured to be dispensed from the application device upon actuation of the actuating device 
     In yet another aspect, a method for controlling a fluid delivery to a body of a patient includes moving a piston and a flexible membrane of a regulator toward an input opening of the regulator, the input opening receiving the fluid from a containment device, contacting an actuator of the regulator with the membrane to open a fluid pathway from the input opening to an output opening of the regulator, and causing a fluid to be released. 
     The method may include compressing a spring adjacent the input opening; and breaking a fluid seal between the input opening and the output to open the fluid pathway between the input opening and the output opening of the regulator. 
     According to another aspect, a device configured to regulate pressure of a fluid includes a first body having an input opening for receiving the fluid, an output opening for delivering the fluid, wherein the first body includes a protrusion extending into the chamber and dividing the chamber into a first chamber adjacent the input opening and a second chamber adjacent the output opening, and wherein the protrusion includes a hole fluidly connecting the first chamber and the second chamber, an X-ring disposed in the first chamber adjacent to the hole, and a second body disposed in the first chamber adjacent the X-ring on a side opposite the hole. 
     The protrusion may have a first surface and a second surface approximately perpendicular to the first surface, wherein each of the first surface and the second surface may face the first chamber. 
     The X-ring may contact two separated portions of at least one of the first surface and the second surface. 
     The X-ring may contact two separated portions of each of the first surface and the second surface. 
     The X-ring may include four protrusions, and the second body may be configured to contact one of the four protrusions in at least one state of the device. 
     The X-ring and the second body may be configured to prevent fluid from passing through the hole in at least one state of the device. 
     The device may further include a first spring disposed in the first chamber and configured to push the second body toward the hole. 
     A fluid path may extend from the input opening, through the first chamber, through the hole, through the second chamber, and out the output opening. 
     The second chamber may define a chamber opening, and the device may further include a flexible membrane contacting the body and having a first surface sealingly covering the chamber opening. 
     The device may further include an actuator surrounding at least a portion of the protrusion and contacting the first surface of the membrane. 
     The device may further include a piston adjacent a second surface of the membrane opposite the first surface and configured to regulate a position of the membrane. 
     The device may further include a second spring disposed between the piston and a cap and configured to force the piston toward the membrane. 
     The second body may include rubber. 
     The X-ring may include silicone. 
     Properties of the second body and X-ring may be such that the second body and X-ring are compatible with temperatures of −50 C. 
     According to another aspect, a device is configured to regulate pressure of a fluid, the device includes a first body having an input opening for receiving the fluid, an output opening for delivering the fluid, and a chamber between the input opening and the output opening, wherein the chamber defines a chamber opening, a flexible membrane contacting the first body and having a first surface sealingly covering the chamber opening, an X-ring disposed in the chamber, a second body disposed in the chamber adjacent the X-ring, and a spring provided in the chambers contacting the second body and configured to urge the second body toward the X-ring. 
     The chamber may at least partially defined by a first surface and a second surface, and wherein the X-ring may contact two separated portions of at least one of the first surface and the second surface. 
     The X-ring may include four protrusions, and the second body may be configured to contact one of the four protrusions in at least one state of the device. 
     According to an aspect, a device may be configured to regulate pressure of a fluid, and the device may include a first body having an input opening for receiving the fluid, an output opening for delivering the fluid, and a chamber in fluid communication with and between the input opening and the output opening, an X-ring disposed in the chamber, a second body disposed in the chamber adjacent the X-ring, a first spring provided in the chamber, contacting the second body, and configured to urge the second body in a first direction, toward the X-ring, a piston, and a second spring configured to push the piston in a second direction, opposite the first direction, toward the X-ring. 
     The chamber may at least partially defined by a first surface and a second surface, and wherein the X-ring may contact two separated portions of at least one of the first surface and the second surface. 
     According to another aspect, a device for fluidizing and delivering a powdered agent comprises a canister extending longitudinally from a first end to a second end and defining an interior space within which a powdered agent is received, an inlet coupleable to a gas source for supplying gas to the interior space to fluidize the powdered agent received therewithin to create a fluidized mixture, an outlet via which the gas mixture is delivered to a target area for treatment, a tube extending from a first end in communication with the outlet to a second end extending into the interior space, the tube including a slot extending through a wall thereof so that gas mixture is passable from the interior space through the outlet via the second end and the slot, and a door movably coupled to the tube so that the door is movable over the slot to control a size of the slot open to the interior space of the canister. 
     In an aspect, the door may be configured as an overtube movably mounted over the tube. 
     In an aspect, the device may further comprise a stabilizing ring extending radially outward from the overtube to an interior surface of the canister to fix the tube relative to the canister. 
     In an aspect, the canister may be rotatable relative to the tube to move the overtube longitudinally relative to the tube and control the size of the slot open to the interior space. 
     In an aspect, the device may further comprise a lid coupleable to the canister to enclose the interior space, the inlet and the outlet configured as openings extending through the lid. 
     In an aspect, the device may further comprise a delivery catheter coupleable to the outlet, the delivery catheter sized and shaped to be inserted through a working channel of an endoscope to the target area. 
     The present aspects are also directed to a device for fluidizing and delivering a powdered agent, comprising a canister extending longitudinally from a first end to a second end and including a first interior space within which a powdered agent is received, a first inlet coupleable to a gas source for supplying gas to the interior space to fluidize the powdered agent received therewithin to create a fluidized mixture, an outlet via which the gas mixture is delivered to a target area for treatment from the first interior space, and a filler chamber in communication with the first interior space via a filler inlet, the filler chamber containing a filler material passable from the filler chamber to the first interior space to maintain a substantially constant volume of material therein, wherein the material includes at least one of the powdered agent and the filler material. 
     In an aspect, the filler material may include one of mock particles, beads, bounce balls, and a foam material. 
     In an aspect, the filler material may be sized, shaped and configured so that the filler material cannot be passed through the outlet. 
     In an aspect, the filler chamber may be supplied with a gas to drive the filler material from the filler chamber into the first interior space. 
     In an aspect, the filler chamber may be configured as a second interior space defined via the canister. 
     In an aspect, the second interior space may include an angled surface directing the filler material to the filler inlet. 
     In an aspect, the filler material may be additional powdered agent. 
     In an aspect, the device may further comprise a door movable relative to the filler inlet between a first configuration, in which the door covers the filler inlet, to a second position, in which the door opens the filler inlet to permit filler material to pass therethrough from the filler chamber to the first interior space via gravity. 
     In an aspect, the device may further comprise a turbine connected to a paddle housed within the filler inlet, the turbine driven by a flow of gas so that, when a flow of gas is received within a flow path housing the turbine, the turbine rotates to correspondingly rotate the paddle so that filler material within the filler chamber is actively driven therefrom and into the first interior space. 
     The present aspects are also directed to a method, comprising supplying a gas to an interior space within a canister within which a powdered agent is received to fluidize the powdered agent, forming a fluidized mixture and delivering the fluidized mixture to a target area within a patient body via a delivery catheter inserted through a working channel of an endoscope to the target area, wherein during delivery of the fluidized mixture, a door movably mounted over the tube is moved relative to a slot extending through a wall of a tube extending into the interior space of the canister in communication with the delivery catheter, to control a size or a portion of the slot exposed to the interior space. 
     The present aspects are also directed to a device for fluidizing and delivering a powdered agent, comprising a canister extending longitudinally from a first end to a second end and defining an interior space within which a powdered agent is received, an inlet coupleable to a gas source for supplying gas to the interior space to fluidize the powdered agent received therewithin to create a fluidized mixture, an outlet via which the gas mixture is delivered to a target area for treatment, and a piston movably coupled to the canister, the piston movable from an initial configuration, in which the piston is coupled to the first end of the canister, toward the second end of the canister to reduce a volume of the interior space as a volume of the powdered agent is reduced during delivery of the fluidized mixture to the target area. 
     In an aspect, each of the inlet and the outlet may extend through a portion of the piston. 
     In an aspect, the outlet may be coupleable to a delivery catheter sized and shaped to be inserted through a working channel of an endoscope to the target area. 
     In an aspect, the piston may be movable via one of a pneumatic cylinder and motor. 
     In an aspect, the device may further comprise a chamber connected to the first end on the canister on a side of the piston opposing the interior space of the canister, the chamber housing an expandable member which is configured to receive gas during delivery of the fluidized mixture so that the expandable mixture expands to move the piston toward the second end of the canister. 
     In an aspect, the expandable member may be configured to be connected to the gas source via a connecting member including a one way valve which permits a flow of gas into the expandable member while preventing a flow of gas out of the expandable member. 
     In an aspect, the device may further comprise a bypass connected to the first end of the canister and coupled to the piston via a threaded rod, the bypass housing a turbine connected to the threaded rod and being configured to receive a flow of gas therethrough so that, when gas flows through the bypass during delivery of the fluidized mixture, the turbine and threaded rod rotate to move the piston toward the second end of the canister. 
     The present aspects are directed to a device for fluidizing and delivering a powdered agent, comprising a canister extending longitudinally from a first end to a second end and including a first interior space within which a powdered agent is received, an inlet coupleable to a gas source for supplying gas to the interior space to fluidize the powdered agent received therewithin to create a fluidized mixture, an outlet via which the gas mixture is delivered to a target area for treatment, and an expandable member movable between an initial biased configuration and an expanded configuration in which the expandable member is deformed so that a portion of the expandable member extends into the first interior space to reduce a volume thereof as a volume of the powdered agent therein is reduced during delivery of the fluidized mixture to the target area. 
     In an aspect, the canister may further include a second interior space configured to receive a gas therein during delivery of the fluidized mixture to the target area. 
     In an aspect, the first and second interior spaces may be separated from one another via an expandable member, a pressure differential between the first and second interior spaces causing the expandable member to deform into the first interior space. 
     In an aspect, the expandable member may be a diaphragm. 
     In an aspect, the first interior space may be defined via an interior wall of the expandable member and the second interior space may be defined via an exterior wall of the expandable member and an interior surface of the canister. 
     In an aspect, the expandable member may be substantially cylindrically shaped. 
     In an aspect, the expandable member may extend from the first end of the canister to the second end of the canister. 
     In an aspect, the expandable member may be a balloon housed within the canister and configured to receive a gas therewithin so that, as the balloon is inflated, the balloon fills the first interior space. 
     The present aspects are also directed to a method, comprising supplying a gas to an interior space within a canister within which a powdered agent is received to fluidize the powdered agent, forming a fluidized mixture, and delivering the fluidized mixture to a target area within a patient body via a delivery catheter inserted through a working channel of an endoscope to the target area, wherein during delivery of the fluidized mixture, a volume of the interior space of the canister is reduced to correspond to a reduction in volume of the powdered agent so that a rate of delivery of the fluidized mixture remains substantially constant. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various exemplary embodiments and together with the description, serve to explain the principles of the disclosed embodiments. 
         FIG.  1    is a perspective view of a medical system according to an embodiment; 
         FIG.  2    is a cross-section of an applicator handle of the medical system of  FIG.  1   ; 
         FIG.  3    is a perspective view of a flow path of the medical system of  FIG.  1   ; 
         FIG.  4    is a perspective view of a locking mechanism of the medical system of  FIG.  1   ; 
         FIG.  5    is a cross-section of the applicator handle of  FIG.  3    including a regulator according to an embodiment; 
         FIGS.  6 A- 6 C  are cross-sections of a regulator according to an embodiment; 
         FIG.  7    is a cross-section of a regulator according to another embodiment; 
         FIG.  8    is a perspective view of a regulator according to an embodiment; 
         FIG.  9    is a perspective view of a body of a regulator according to an embodiment; 
         FIG.  10    is a perspective view of a capture cylinder of a regulator according to an embodiment; 
         FIGS.  11 A and  11 B  are cross-sections of a regulator according to still another embodiment; 
         FIG.  12    is a perspective view of a portion of the medical system of  FIG.  1   ; 
         FIG.  13    is a perspective view of a chamber of the medical system of  FIG.  1   ; 
         FIGS.  14 A and  14 B  are perspective views of the chamber of  FIG.  13   ; 
         FIG.  15    shows a schematic view of a chamber according to another embodiment, in a first configuration; 
         FIG.  16    shows a perspective view of the device of  FIG.  15   , in a second configuration; 
         FIG.  17    shows a schematic view of a device according to another embodiment of the present disclosure; 
         FIG.  18    shows a schematic view of a device according to an alternate embodiment of the present disclosure; 
         FIG.  19    shows a schematic view of a device according to yet another embodiment of the present disclosure; 
         FIG.  20    shows a lateral cross-sectional view of the device of  FIG.  19    along the line  19 - 19 ; 
         FIG.  21    shows a schematic view of a device according to another embodiment of the present disclosure; 
         FIG.  22    shows a schematic view of a device according to yet another embodiment of the present disclosure, in a first configuration; 
         FIG.  23    shows a schematic view of the device of  FIG.  22   , in a second configuration; 
         FIG.  24    shows a schematic view of a device according to an alternate embodiment of the present disclosure, in a first configuration; 
         FIG.  25    shows a schematic view of the device of  FIG.  24   , in a second configuration; 
         FIG.  26    shows a schematic view of a device according to an embodiment of the present disclosure; 
         FIG.  27    shows a schematic view of a device according to an alternate embodiment of the present disclosure; 
         FIG.  28    shows a schematic view of a device according to another alternate embodiment of the present disclosure; 
         FIG.  29    shows a bottom view of the device according to  FIG.  28   ; 
         FIG.  30    shows a schematic view of a device according to another embodiment of the present disclosure; 
         FIG.  31    shows a schematic view of a device according to yet another embodiment of the present disclosure; 
         FIG.  32    shows a schematic view of a device according to another embodiment; 
         FIG.  33    shows a schematic view of device according to yet another embodiment of the present disclosure; 
         FIG.  34    shows a schematic view of a device according to an alternate of the present disclosure; and 
         FIG.  35    is a perspective view of a catheter of the medical device of  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure is now described with reference to exemplary medical devices that may be used in dispensing materials. However, it should be noted that reference to any particular procedure is provided only for convenience and not intended to limit the disclosure. A person of ordinary skill in the art would recognize that the concepts underlying the disclosed devices and application methods may be utilized in any suitable procedure, medical or otherwise. The present disclosure may be understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. 
     For ease of description, portions/regions/ends of a device and/or its components are referred to as proximal and distal ends/regions. It should be noted that the term “proximal,” as it relates to an application device, is intended to refer to ends/regions closer to an inlet of a propellant gas to the application device (e.g., at a location of the application device where the propellant gas is released from a containment device into the application device), and the term “distal,” as it relates to an application device, is used herein to refer to ends/regions where the propellant gas and/or any material is released from the application device to a target area or, if a catheter is attached to the application device, from the catheter to the target area. Similarly, extends “distally” indicates that a component extends in a distal direction, and extends “proximally” indicates that a component extends in a proximal direction. Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the features, as claimed. As used herein, the terms “comprises,” “comprising,” “having,” “including,” or other variations thereof, are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements, but may include other elements not expressly listed or inherent to such a process, method, article, or apparatus. In this disclosure, relative terms, such as, for example, “about,” “substantially,” “generally,” and “approximately” are used to indicate a possible variation of ±10% in a stated value or characteristic. 
     Referring to  FIG.  1   , a medical system, e.g., a delivery system,  10  according to an embodiment is shown. Delivery system  10  includes a containment device  20  and an application device  30 , e.g., a hand-held device, connected thereto by a conduit  22 . As will be described herein, application device  30  may be attached directly to, or otherwise be integrated with, containment device  20  without conduit  22  therebetween (see e.g.,  FIG.  2   ). As further shown in  FIGS.  1 - 3   , application device  30  includes an inlet  32 , an outlet  34 , and actuating devices  36   a ,  36   b . According to an example, outlet  34  may be a male or a female luer fitting, but is not limited to this configuration. As will be explained herein, the propellant fluid and/or any additional material is expelled into catheter  190  via outlet  34 , allowing a user to output the propellant fluid at a desired location. Examples of apparatuses for delivering powdered agents are found in U.S. patent application Ser. No. 16/259,024, entitled “Apparatuses and Methods for Delivering Powdered Agents,” and filed on Jan. 28, 2019, the complete disclosure of which is incorporated by reference herein. 
     With reference to  FIG.  1   , containment device  20  is configured to contain a fluid, such as a gas, e.g., carbon dioxide or any other gas of fluid known in the art. While shown as a box, containment device  20  may be any shape, such as a torpedo-shape (see e.g.,  FIG.  2   ), a sphere, or any other shape known in the art for containing gas. For example, containment device  20  could be a carbon dioxide tank or cylinder typically formed in medical settings, such as a hospital. Containment device  20  includes one or more outer walls defining one or more inner chambers (not shown), the inner chamber(s) configured to contain the fluid. The walls of containment device  20  may be formed of any material suitable for containing the fluid, such as but not limited to a metal alloy, a ceramic, or other material known in the art. The fluid contained in the inner chamber of containment device  20  may be under pressure. Accordingly, the walls are formed of a material and/or a thickness suitable to contain the fluid at a pressure of, for example, at least approximately 1000 pounds per square inch (PSI), or approximately 850 PSI. For example, gases which may be contained in containment device  20  include carbon dioxide (CO 2 ) having a vapor pressure of approximately 2,000-8,000 kPa at typical device temperatures, or nitrogen (N2) having a vapor pressure less than 40 MPa at typical device temperatures. It will be understood that these gases are examples and are not limiting to the types of gases contained in containment device  20 . 
     With continued reference to  FIG.  1   , application device  30  is attached to containment device  20  via conduit  22 . Conduit  22  may supply fluid under pressure from containment device  20  to application device  30 . As will be described in greater detail herein, actuation of actuating devices  36   a ,  36   b  causes fluid to move from containment device  20 , through conduit  22 , and to application device  30 , allowing a user to output the fluid at a desired location via catheter  190 . Conduit  22  may be made of any material, for example reinforced rubber or a suitable plastic, that allows conduit  22  to withstand the pressures of the fluid, while simultaneously allowing for unrestricted movement of conduit  22 . Conduit  22  may be attached to containment device  20  and application device  30  by any attachment device, including but not limited to screw-type connectors, pressure washer adapters, or any other device known in the art. 
     According to another embodiment, application device  30  may be connected directly to containment device  20 ′, without any intervening structure, as shown in  FIG.  2   . For example, inlet  32  may be connected directly to an output, such as a protuberance of containment device  20 ′ using a threaded connection, pressure washer adapter, or the like. The protuberance of containment device  20 ′ may extend into inlet  32  of application device  30  and connect, directly or via an intervening structure, e.g., a lumen, to a regulator  40 . Directly connecting application device  30  to containment device  20 ′ may be suitable for, e.g., a small-volume containment device  20 ′ containing approximately 5 g to 75 g of compressed gas, or preferably approximately 12 g to 40 g of compressed gas, to allow for greater portability of delivery system  10 . 
     Referring to  FIG.  1   , actuation of actuating devices  36   a ,  36   b  of application device  30  causes the fluid to exit delivery system  10  through outlet  34  of application device  30 . It will be understood that only one actuating device  36   a ,  36   b  may need to be actuated in some embodiments. Alternatively, or additionally, a plurality of actuating devices  36   a ,  36   b  may be simultaneously actuated to release fluid as, for example, a safety precaution. As will be described herein, actuation of actuating device  36   a ,  36   b  releases a buildup of pressure within delivery system  10 , causing regulator  40  to release fluid from containment device  20 ′ at a predetermined pressure. Application device  30  may be, e.g., a handle such as a garden-hose handle or other pistol-like configuration. Actuating device  36   a ,  36   b  may be any push button, trigger mechanism, or other device that, when actuated, opens a valve and releases fluid, as will be described in greater detail herein. 
     With reference to  FIG.  2   , application device  30  is attached directly to a torpedo-shaped containment device  20 ′, without any intervening structure. Containment device  20 ′ may be attached to inlet  32  of application device  30  by any attachment device  38 , including but not limited to screw-type connectors, pressure washer adapters, a pierce pin and seal arrangement, or any other device known in the art. It will also be understood that attachment device  38 , or any other device for attaching containment device  20 ′ to application device  30 , may include an actuator  39  (e.g., a tab, a button, etc.) for opening or rupturing a burst disc or pressure release valve attached to containment device  20 ′ and/or application device  30 . Actuator  39  may be actuated at an end of a procedure to vent any remaining propellant fluid from containment device  30 . An alert, such as a tactile or an audible alert, may be generated when containment device  20 ′ is attached to application device  30 . Alternatively, containment device  20 ′ may be attached to application device  30  by a locking mechanism  50 , as will be described in greater detail below. Additionally, a cap  150  may be attached by screw fit, snap fit, or any other attachment mechanism to a handle  31  of application device  30 . For example, cap  150  may be attached to an end of handle  31  opposite attachment device  38 . Cap  150  may provide additional support to secure containment device  20 ′ to application device  30 . 
     As discussed above, one or more regulators  40  may assist in regulating an amount of propellant fluid released from containment device  20 ′ at a specific pressure, as will be described in greater detail with reference to  FIGS.  5 - 11 B . For example, regulator  40  may be a dual stage regulator, or regulator  40  may be two single stage regulators, such as two piston regulators, aligned in series. As will be discussed in greater detail below, regulator  40  may include a pierce pin  670  (see  FIG.  6 A ) to pierce a seal of containment device  20 ′ when containment device  20 ′ is attached to application device  30 . Alternatively, a separate device, such as a pierce pin or other mechanism for rupturing a seal of containment device  20 ′, may be provided at inlet  32  of application device  30 . Further, inlet  32  may provide an all-or-nothing scenario in which the containment device  20 ′ is completely attached or completely detached from application device  30  using, e.g., gaskets or washers (not shown) to prevent leakage at inlet  32 . A propellant fluid pressure may further be adjusted by a membrane regulator  44  provided in series after regulator  40 . The combination of regulator  40  and membrane regulator  44  may reduce the pressure of gas from containment device  20 ′ to an acceptable outlet pressure, i.e., a pressure of the gas and any material at outlet  34 . A pressure of a gas within delivery system  10 , after regulators  40 ,  44 , and at a target area in a patient, may be predetermined, based on the tissue to which the gas and material is being dispensed. An acceptable pressure at outlet  34  may be approximately plus or minus 40% deviation from the target pressure, more preferably approximately plus or minus 25% deviation from the target pressure. For example, regulator  40  may reduce inlet pressure of the dispensing propellant fluid to approximately 50-150 PSI, and membrane regulator  44  may subsequently reduce the propellant fluid to approximately 20-50 PSI. According to an example, regulator  40  and membrane regulator  44  reduce the propellant fluid to the desired output pressure of the propellant fluid based on a predetermined setting during manufacturing. Alternatively, or additionally, one or both of regulator  40  and membrane regulator  44  may include a mechanism (not shown) for adjusting the pressure of the propellant fluid output from each regulator. Further, the pressure of the propellant fluid at an outlet of membrane regulator  44  may be approximately equal to the pressure of the propellant fluid at outlet  34 . Alternatively, the pressure of the propellant fluid at outlet  34  may be different from the pressure of the propellant fluid at the outlet of membrane regulator  44 . 
     With reference to  FIGS.  2  and  3   , two fluid paths diverge at a Y-connector  45 , which is just distal to an outlet of membrane regulator  44 . A first fluid path  46 , which may be a purge path and which may bypass a material-containing container, may be controlled by actuating device  36   b . For example, first fluid path  46  may bypass a container  100  to release propellant fluid from membrane regulator  44  directly to outlet  34 . First fluid path  46  allows propellant fluid from containment device  20 ′ to purge catheter  190  to remove any debris provided therein. A second fluid path  48  may be controlled by actuating device  36   a  to direct propellant fluid from membrane regulator  44 , through container  100 , to outlet  34 . Second fluid path  48  allows the propellant fluid to enter container  100 , which contains powder or other material to be dispensed as discussed in greater detail below, mix with the powder or material contained therein, and transport the mixture through outlet  34  to a target site, via catheter  190 . According to an example, propellant fluid travels through first fluid path  46  at approximately 8-12 standard liters per minute (SLPM), or preferably approximately 10 SLPM. Alternatively, propellant fluid may travel through first fluid path  46  at approximately 4-6 SLPM, or preferably approximately 5 SLPM. Propellant fluid travels through second fluid path  48  at approximately 0.5-4.5 SLPM, or preferably approximately 2 SLPM. 
     Flow paths of propellant fluid, including fluid paths  46  and  48 , are shown in  FIG.  3   . Propellant fluid flows along first pathway J from regulator  40 , through membrane regulator  44 , and to a junction of first fluid path  46  and second fluid path  48 . At the junction of first fluid path  46  and second fluid path  48 , pathway J splits into second pathway K and third pathway M. Second pathway K travels along first fluid path  46  to second actuating device  36   b . When actuated, second actuating device  36   b  dispenses dispensing fluid along fourth pathway L (distal to second actuating device  36   b ), which terminates at outlet  34 . First pathway J, second pathway K, and fourth pathway L form first fluid path  46 . Alternatively, propellant fluid from first pathway J may follow third pathway M to first actuating device  36   a . When actuated, first actuating device  36   a  dispenses propellant fluid along fifth pathway N (distal to first actuating device  36   a ) and each of a plurality of sixth pathways O, which provide propellant fluid to container  100  through filter holes  104   a  (see  FIG.  12   ). Propellant fluid mixes with material provided in container  100  (a housing  107  of container  100 , as shown in  FIG.  12   , is not shown in  FIG.  3    for ease of understanding), as will be described herein, and the mixture travels from container  100  along seventh pathway O′, which leads from an outlet (described below) of container  100  to a chamber outlet  114  (see  FIGS.  14 A and  14 B ), and eighth pathway P, which leads along chamber outlet  114  to outlet  34 . First, third, fifth, sixth, seventh, and eighth pathways J, M, N, O, O′, P, respectively, form second fluid path  48 . Further, first, third, and fifth pathways J, M, and N form a proximal portion of second fluid path  48 , eighth pathway P forms a distal portion of second fluid path  48 , and sixth and seventh pathways O, O′ form an intermediate portion of second fluid path  48 . As shown in  FIG.  3   , first-eighth pathways J-P are tubes or lumen extending through and/or interconnecting elements of medical device  10 . These tubes and/or lumen may be formed of medical grade plastic, metal, ceramic, or any other suitable material for moving propellant fluid and/or material throughout medical device  10 . 
     A locking mechanism  50  for securing containment device  20 ′ will be described with reference to  FIG.  4   . Locking mechanism  50  may replace cap  150  in  FIG.  2   . Locking mechanism  50  includes a lever  52  pivotally connected to handle  31  of application device  30  at pivot axis R. Lever  52  includes a cam path  54  defining a curved path, and a locking notch  56  at one end of the cam path  54 . A pin  57  extends generally perpendicular from a shaft  60 , and pin  57  rides along cam path  54  between locking notch  56  and an opposite end of cam path  54 . Shaft  60  extends along a longitudinal axis of handle  31  and includes a piston head  58  attached to an end of shaft  60  opposite pin  57 . As shown in  FIG.  4   , a bottom surface of containment device  20 ′ sits on a top surface of piston  58 . Lever  52  is angled with respect to handle  31  when locking mechanism  50  is unlocked, e.g., when introducing or removing containment device  20 ′ from handle  31 . Lever  52  rotates about pivot axis R, causing pin  57  to ride in cam path  54  from the first end to the locking notch  56 . Pin  57  locks in locking notch  56  when lever  52  is substantially parallel to handle  31 . The curvature of cam path  56  forces shaft  60  and piston  58  against the bottom surface of containment device  20 ′, moving containment device  20 ′ toward a pierce pin (not shown, see, e.g., pierce pin  670  in  FIG.  6 A ), causing the pierce pin to rupture a seal (not shown) on containment device  20 ′ and fluidly connect containment device  20 ′ to application device  30 . In one example, cavities  20   a  extend into a bottom surface of containment device  20 ′ and receive protrusions  58   a  extending from a topmost surface of piston  58 , thereby removably connecting containment device  20 ′ and piston  58 , and preventing containment device  20 ′ from slipping with respect to piston  58 . Alternatively, or additionally, the topmost surface of piston  58  and/or the bottommost surface of containment device  20 ′ may include a textured surface, such as abrasions, knurls, cavities, slots, or any other friction-increasing coating to increase the friction between containment device  20 ′ and piston  58  to maintain a relative position between containment device  20 ′ and piston  58 . This configuration may aid containment device  20 ′ to be properly urged toward the pierce pin and to properly seal containment device  20 ′ to application device  30 . 
     Referring to  FIG.  5   , many elements of application device  30  are stripped away to show a position of regulator  40 . It will be understood that the position of regulator  40  within application device  30  is only meant for example, and is not limited to that shown in  FIG.  5   . 
     With reference to  FIGS.  6 A and  8   , regulator  40  according to an embodiment will be described. Regulator  40  includes a body  650  (including an input opening  652  and an output opening  654 , each for communication to external environment), a cap  700 , and a capture cylinder  710  (e.g., capture member). A membrane  730  is provided between a piston  690  and an actuator  680 . As further shown in  FIG.  6 A , regulator  40  includes a pierce pin  670 , first and second springs  740 ,  742 , a ball bearing  750  (or another type of body), and an O-ring  760 . 
     With reference to  FIGS.  6 A and  9   , body  650  of regulator  40  is generally cylindrical and has a central axis A. Body  650  includes a regulator wall  656 , and a first chamber  658  (adjacent input opening  652 ) and a second chamber  660 , each defined within regulator wall  656 . Regulator wall  656  may include screw threads on a radially-outer surface of wall  656  for attachment to additional structures, as discussed herein. An inner diameter of regulator wall  656  in first chamber  658  is smaller than an inner diameter of regulator wall  656  in second chamber  660 . A cylindrical protrusion  662  extends into second chamber  660 , cylindrical protrusion  662  having a hole  664  at it upper end, transverse to and coaxial with central axis A. Hole  664  is in fluid communication with a third chamber  666 , defined by an inner wall  662   a  of cylindrical protrusion  662 . Third chamber  666  is in fluid communication with, and between, first chamber  658  and second chamber  660 . According to an embodiment, there is no O-ring or other sealing member provided in second chamber  660 , thereby eliminating friction forces at and between regulator wall  656  and actuator  680  during movement of actuator  680 . Additionally, body  650  may be any material known in the art, including but not limited to a metal alloy, a ceramic, and/or a resin. 
     As shown in  FIG.  6 A , O-ring  760  is disposed adjacent to inner wall  662   a , within third chamber  666 , and lies adjacent to hole  664 . Ball bearing  750  is adjacent to O-ring  760  on a side opposite hole  664 . As will be described herein, ball bearing  750  and O-ring  760  are capable of sealing hole  664  from communication with third chamber  666 . Second spring  742  is disposed in third chamber  666  between, and in contact with both of, pierce pin  670  and ball bearing  750 . Second spring  742  is sized to have an outer diameter smaller than a diameter of inner wall  662   a , such that second spring  742  can expand and contract without creating friction forces between it and inner wall  662   a . O-ring  760  and ball bearing  750  are sized such that an outer diameter of each is less than the inner diameter of inner wall  662   a . In that way, when O-ring  760  and/or ball bearing  750  are not sealing hole  664 , fluid flows within chamber  666 , between inner wall  662   a  and ball bearing  750 , within and/or around O-ring  760 , and through hole  664  to chamber  660 . According to an example, a seal effective diameter where ball bearing  750  seals against O-ring  760  is approximately 0.05 inches to 0.14 inches, and preferably approximately 0.08 inches to 0.11 inches. 
     With continued reference to  FIG.  6 A , first chamber  658  is in fluid communication with third chamber  666 , via a pierce pin chamber  676  within pierce pin  670 . First chamber  658  includes an area having a first diameter (defined by wall surface  656   a ) and an area having a second, smaller diameter (defined by wall surface  656   b ). Surfaces of first chamber  658  may include threads (not shown) to accommodate components which may be used to pierce containment device  20 ′. Alternatively, threads of surfaces of first chamber  658  may accommodate a threaded containment device  20 ′. For example, when containment device  20 ′ is screwed into first chamber  658  (using, e.g., threads), pierce pin  670  may pierce containment device  20 ′. Third chamber  666  is adjacent to, and has a smaller diameter than, the second diameter area of chamber  658 . The confluence of the second diameter area of chamber  658  and third chamber  666  defines a notch  668  outside and along a perimeter of third chamber  666 . Notch  668 , at its top, defines an annular flanged surface  668   a.    
     Pierce pin  670  is shown in  FIG.  6 A . According to an embodiment, pierce pin  670  may be disposed in notch  668  and abut flanged surface  668   a . According to an embodiment, pierce pin  670  may have an outer diameter equal to an inner diameter of the second diameter area of chamber  658 . Pierce pin  670  includes a body portion  672  and a protrusion  674  extending from body portion  672  into chamber  658 , pierce pin  670  defines pierce pin chamber  676  open at both ends, and extending through body  672  and protrusion  674 . First chamber  658  may be in fluid communication with pierce pin chamber  676  via opening  675 . A first portion of chamber  676  adjacent to chamber  666  has a larger diameter than a second portion of chamber  676  adjacent to chamber  658 . According to an embodiment, protrusion  674  includes an end wall  674   a  angled relative to central axis A, preferably not perpendicular to central axis A. Pierce pin  670  may be fixed to body  650  by, for example, adhesive, friction between body  650  and pierce pin  670 , welding, threads, etc. Additionally, or alternatively, pierce pin  670  may be formed as a single structure with body  650  through, for example, additive manufacturing. Pierce pin  670  may have any suitable geometry, including, for example, an arrow shape (not shown). In such a configuration, instead of having a protrusion  674 , surfaces of pierce pin  670  may slope radially outwardly from a narrow portion proximate to opening  675 . The sloped surfaces may terminate in a shoulder portion and include a stem extending from the shoulder portion, into third chamber  666 . An arrow-shaped pierce pin  670  may facilitate forming a relatively large hole in containment device  20 ′. Air may flow through opening  675  and the stem portion, into third chamber  666 . 
     According to an embodiment, protrusion  674  of pierce pin  670  pierces a gasket of containment device  620  or conduit  622 . Alternatively, or additionally, protrusion  674  interacts with a device (not shown) on containment device  20 ′ or conduit  22 , such as locking with the device, providing a fluid connection between regulator  40  and containment device  20 ′ or conduit  22 . According to an embodiment, pierce pin  670  may be any material known in the art, including but not limited to a metal alloy, a ceramic, and/or a resin. 
       FIG.  6 A  further illustrates actuator  680 , which is a cylindrical member having an outer actuator wall  682  and a top wall  683  defining an actuator chamber  684 . Actuator chamber  684  is open at one end of actuator  680 , the end facing the bottom of  FIG.  6 A  opposite top wall  683 . According to an embodiment and as shown in  FIG.  6 A , actuator  680  may include a throughhole  686  in actuator wall  682  near top wall  683 , as will be described in greater detail herein. According to an embodiment, a central axis of though hole  686  is perpendicular to a prong  688 . Additionally, as shown in  FIG.  6 A , prong  688  may extend from top wall  683  into chamber  684 . Prong  688  may be perpendicular to top wall  683 , extending along central axis A into through hole  664  and into chamber  666 . When assembled, actuator  680  is provided in second chamber  660  and annularly surrounds at least a portion of cylindrical protrusion  662 . Actuator  680  and cylindrical protrusion  662  are sized such that an outer wall  662   b  of cylindrical protrusion  662  has a diameter smaller than a diameter of an inner wall  680   a  of actuator  680 , thereby forming an annular space  665  between actuator  680  and cylindrical protrusion  662 . In this way, actuator  680  can slide (translate) along central axis A and fluid can flow between actuator  680  and cylindrical protrusion  662  in space  665 . According to an embodiment, actuator  680  may be any material known in the art, including but not limited to a metal alloy, a ceramic, and/or a resin. 
     With continued reference to  FIG.  6 A , piston  690  is generally cylindrical in shape, including an outer piston wall  692  and a bottom wall  693 , an inner surface of piston wall  692  and an upper surface of wall  693  defining a piston chamber  694 , with piston chamber  694  being open at an upper end opposite wall  693 . According to an embodiment, piston  690  may be any material known in the art, including but not limited to a metal alloy, a ceramic, and/or a resin. 
     Cap  700  is also generally cylindrical in shape, having a cap outer wall  702  and an upper cap wall  703 , together defining a cap chamber  704 , which is open at one end. Protuberance  706  extends from, and generally perpendicular to, upper cap wall  703 . As shown in  FIG.  6 A , spring  740  is provided in piston chamber  694 . A first end of spring  740  contacts an inner upper surface of piston wall  693 . Spring  740  extends up to and encircles at least a portion of protuberance  706 , such that an end of spring  740  opposite the first end contacts an inner, lower surface of upper cap wall  703 . A hole (not shown) may be formed in upper cap  703  above a protuberance chamber  707  formed by walls of protuberance  706 , such that chamber  707  and piston chamber  694  may be in fluid communication with the atmosphere. Such a hole may relieve vacuum or pressure built up in piston chamber  694  as membrane  732  moves as described below. 
       FIGS.  6  and  10    illustrate capture cylinder  710 , which is generally cylindrical in shape. A first wall  712  defines a first chamber  716 , and a second wall  714 , connected by a step portion  720  to first wall  712 , defines a second chamber  718 . First chamber  716  and second chamber  718  are fluidly connected, and capture cylinder  710  is open at the ends of first chamber  716  and second chamber  718 . According to an embodiment, a diameter of first chamber  716  is greater than a diameter of second chamber  718 ; however, capture cylinder  710  is not limited to this configuration. As shown in  FIG.  6 A , piston  690  rests inside second chamber  718  such that the open end of piston chamber  694  and the open end of second chamber  718  face a same direction (the top of  FIG.  6 A ). Piston  690  is sized and shaped to slide within second chamber  718 , as will be described in greater detail herein. For example, an outer diameter of wall  692   a  of piston  690  is smaller than a diameter of an inner wall  714   a  of capture cylinder  710 , thereby reducing and/or eliminating friction forces between piston  690  and capture cylinder  710 . This reduced friction provides more freedom of movement between elements, thereby improving the consistency of the output pressure and flow rate of the fluid. 
     As shown in  FIGS.  6  and  10   , an outer portion of second wall  714  includes a thickened annular region  724 . Region  724  includes walls  722  which taper to the thinner regions of second wall  714 . According to an embodiment, first wall  712  and second wall  714  are generally parallel to central axis A and perpendicular to wall  720 , but are not limited to this configuration. As shown in  FIG.  6 A , region  724  allows cap  700  to be fixedly attached to and seal capture cylinder  710 . For example, cap  700  may be snap-fit, welded, glued, screwed, or attached in any manner known in the art to capture cylinder  710 . Attachment of cap  700  to capture cylinder  710  may allow cap  700  to be removed, for example, using screw threads. Alternatively, cap  700  may be fixedly secured to cylinder  710  and unable to be removed without destroying regulator  40 , for example, by welding cap  700  to capture cylinder  710 . Cap  700  may be configured so as to compress spring  740  by a predetermined amount in a relaxed state of regulator  40 , when pressurized fluid is not flowing into/through regulator  40 . The predetermined compression of spring  740  may determine a pressure that is output via output opening  654  when high pressure fluid flows through input opening  652 . A compression of spring  740  by cap  700  may be adjustable after regulator  40  is assembled (e.g., to allow for varying output pressures) or could be fixed during assembly of regulator  40 . 
     With continued reference to  FIG.  6 A , membrane  730  is provided in first chamber  716  of capture cylinder  710 . Membrane  730  includes a base  732  and a wall  734  extending along a circumference of and generally perpendicular to base  732 . According to an embodiment, membrane  730  is formed of a silicone material, but is not limited thereto. For example. membrane  730  may be any material which is flexible and reduces a friction coefficient between membrane  730  and the other structures of regulator  40 . 
     As shown in  FIG.  6 A , membrane  730  covers top wall  683  and the upper opening of second chamber  660  of body  650 . An inner diameter of wall  734  is approximately equal to an outer diameter of an upper portion of regulator wall  656  of body  650 , allowing membrane  730  to seal the upper opening of second chamber  660 . As will be discussed herein, this prevents fluid from escaping body  650  (other than through output opening  654 ) during operation of regulator  40 . When assembled, a lower surface of step portion  720  of capture cylinder  710  contacts a top surface of base  732  and fixes membrane  730  to base  650 . In that way, membrane  730  is squeezed between cylinder  710  and base  650 . For example, as shown in  FIG.  6 A , capture cylinder  710  is screwed to body  650 , but may be snap-fit, welded, glued, or attached in any manner known in the art. Alternatively, or additionally, membrane  730  may be fixed to base  650  independent of capture cylinder  710 , such as using an adhesive. According to an example, to reduce the sensitivity of a changing pressure at inlet  632 , membrane effective diameter, which is the outer diameter of second chamber  660  in contact with membrane  730 , is approximately 0.6 inches to 1.25 inches, and preferably 0.7 inches to 1.0 inch. 
     An operation of regulator  40  will now be described. 
       FIG.  6 A  shows regulator  40  in a configuration in which third chamber  666  is sealed, meaning that fluid may not pass through hole  664  and that third chamber  666  is not in fluid communication with second chamber  660  and output opening  654 .  FIG.  6 B  shows regulator  40  in a configuration in which third chamber  666  is not sealed (fluid may pass through hole  664  such that third chamber  666  is in fluid communication with second chamber  660  and output opening  654 ), but regulator  40  is not receiving high pressure fluid from a source such as containment device  20 ,  20 ′.  FIG.  6 C  shows regulator  40  in a configuration in which third chamber  666  is not sealed (fluid may pass through hole  664  such that third chamber  666  is in fluid communication with second chamber  660  and output opening  654 ) and regulator  40  is receiving high pressure from a fluid source such as containment device  20 ,  20 ′. 
     With reference to  FIG.  6 B , when regulator  40  is not exposed to any high pressure (e.g., when a containment device  20 ,  20 ′, which is not shown in  FIGS.  6 A- 6 C , is not installed or when pierce pin  670  has not yet punctured containment device  20 ,  20 ′), regulator  40  is in a resting state of equilibrium, as shown in  FIG.  6 B . In the resting state, spring  740  may exert a force in a first direction along central axis A, toward pierce pin  670 . The force in the first direction from spring  740  may be transmitted to piston  690  and membrane  730 , which may transmit a force in the first direction to actuator  680  (including prong  688 ). When prong  688  is in contact with ball bearing  750 , prong  688  may transmit a force in the first direction to ball bearing  750  and, in turn, to spring  742 . 
     Meanwhile, spring  742  may exert a force in a second, opposite direction along central axis A, toward upper cap wall  703  (a direction opposite the force exerted by spring  740 ). A force from spring  742  may be transmitted to ball bearing  750 , which may, via contact with prong  788 , exert a force in the second direction on actuator  780 , membrane  730 , piston  690 , and spring  740 . Spring  742  may be configured to urge ball bearing  750  in the second direction, toward O-ring  760 . 
     A spring constant of spring  740  may be larger than a spring constant of spring  742  (i.e., spring  740  may be stiffer than spring  742 ). Due to the larger spring constant of spring  740 , spring  740  may dominate spring  742 . In the resting state of  FIG.  6 B , membrane  730  may be deformed such that it protrudes in the first direction, toward pierce pin  670 . Prong  688  may press in the first direction against ball bearing  750  such that there is a gap between ball bearing  150  and O-ring  160 , and third chamber  666  is unsealed/open, so that fluid may pass through hole  664  and third chamber  666  is in fluid communication with second chamber  660  and output opening  654 . 
     After high pressure is introduced to regulator  40 , as shown in  FIG.  6 C , high-pressure fluid may pass through input opening  652 , through pierce pin chamber  676 , and into third chamber  666 . Fluid may then pass through the gap between ball bearing  750  and through hole  664  into actuator chamber  684 . Fluid may then flow between actuator  680  and protrusion  662  to second chamber  660 . As shown in  FIG.  6 C , fluid may also pass via throughhole  686  to second chamber  660 . Fluid subsequently passes as a fluid through output opening  654  (shown by arrow E). 
     When actuating devices  634  are not actuated, valves (not shown) are closed, and fluid does not flow through delivery system  10 . Fluid may be prevented from passing downstream (toward outlet  34 ) of a portion of delivery system  10  (e.g., a valve) controlled by actuating devices  36   a ,  36   b . Therefore, pressure may build up in portions of system  10  that are upstream (away from outlet  34 ) of that portion (e.g., valve) of delivery system  10 . Regulator  40  may be upstream of that portion (e.g., valve), and therefore pressure may build up in regulator  40 . 
     The increasing pressure within regulator  40  may affect various components of regulator  40  and may cause regulator  40  to transition from the configuration of  FIG.  6 C  (open/unsealed) to the configuration shown in  FIG.  6 A  (closed/sealed). For example, pressurized fluid building in second chamber  660  may result in a force on membrane  730  in the second direction. This force may be transmitted to piston  690  and spring  740 . Pressurized fluid in third chamber  666  may also result in a force on ball bearing  750  in the second direction. This force on ball bearing  750  may be transmitted to actuator  680 , membrane  730 , piston  690 , and spring  740 . 
     These additional forces in the first direction may overcome a force of spring  740  in the first direction, such that ball bearing  750 , actuator  680 , membrane  730 , and piston  690  move in the second direction, toward upper cap wall  703 . Membrane  730  may be flat or approximately flat in the configuration shown in  FIG.  6 A , as shown. Membrane  730  may also be capable of deforming further in the second direction so that membrane  730  protrudes in the second direction. For example, membrane  730  may protrude or bow in the second direction when sufficient force is exerted on ball bearing  750 , such as in a fully pressurized configuration. It will be appreciated that  FIGS.  6 A- 6 C  are merely exemplary and that a range of positions of the components of regulator  40  may be possible. For example, in a resting equilibrium (when regulator  40  is not exposed to pressurized fluid), membrane  730  may be straight and may protrude in the second direction when regulator  40  is pressurized. 
     In the configuration of  FIG.  7 A , ball bearing  750  may press against O-ring  760 , forming a seal between ball bearing  750  and O-ring  760 . When ball bearing  750  and O-ring  760  are sealed, third chamber  666  may be sealed such that fluid may not move through hole  664  into actuator chamber  684 . Arrows in  FIG.  6 A  show a path of fluid flow when fluid is flowing into input opening  652  but cannot exit hole  664 . Thus, a pressure of fluid in second chamber  660  (and areas downstream of output opening  654 ) may be capped at a certain value (e.g., the regulated pressure of between 25 and 100 PSI, as discussed below). As discussed in further detail below, this regulation of pressure in second chamber  660  occurs both when actuating devices  634  are actuated or are not actuated. This pressure regulation protects components of delivery system  10 , as well as a subject of a procedure using delivery system  10 . Eventually, where a discrete containment device  20 ,  20 ′ is used, pressure in third chamber  666  may equalize with a pressure of containment device  20 ,  20 ′, such that fluid no longer flows from containment device  20 ,  20 ′ through input opening  652 . 
     When actuating devices  36   a ,  36   b  are opened, fluid may be free to travel from outlet  34  because downstream valves are open. Thus, fluid may flow from second chamber  660  and out of output opening  654 , thereby equalizing pressure between second chamber  660  and the atmosphere surrounding application device  30 . Because second chamber  660  is no longer at a high pressure, the fluid in second chamber  660  may no longer exert a force in the second direction on membrane  730 . As a result, the net force along the second direction may decrease (although high-pressure fluid continues to exert a force on ball bearing  750  in the second direction), and regulator  40  may transition to a configuration like that shown in  FIG.  6 C . The force of spring  740  pushing against piston  690  and membrane  730  in the first direction causes actuator  680  to move toward pierce pin  670  along central axis A. Movement of actuator  680  toward pierce pin  670  causes prong  688  to push ball bearing  750  against spring  742 , thereby providing an opening through hole  664  of protrusion  662 . It will be appreciated that an amount that hole  664  is open may vary depending on a balance of the forces in the first direction (exerted by spring  740 ) and in the second direction (exerted by spring  742 , and high-pressure fluid on membrane  730  and ball bearing  750 ).  FIG.  6 C  shows an exemplary open configuration. However, portions such as membrane  730 , actuator  680 , and/or ball bearing  750  may vary in their position depending on the balance of forces acting at that time, allowing more or less fluid to pass through hole  664 . A varying amount of fluid passing through hole  664  may facilitate maintaining second chamber  660  at a desired regulated pressure (described in further detail below). 
     While the third chamber  666  is unsealed ( FIG.  6 C ), pressurized fluid may flow from containment device  20 ,  20 ′, through input opening  652 , and through hole  664 . For example, as shown in  FIG.  6 C , a flow path (arrows in  FIG.  6 C ) shows a fluid input I through input opening  652 . Fluid flows in the direction of the arrows through pierce pin chamber  676  and into third chamber  666 . Fluid flows through hole  664  into actuator chamber  684 , and flows between actuator  680  and protrusion  662  to second chamber  660 . As shown in  FIG.  6 C , fluid may also pass via throughhole  686  to second chamber  660 . Fluid subsequently passes as a fluid through output opening  654  (shown by arrow E). The fluid output is controlled by regulator  40 , as described herein. While not shown, one or more devices, such as a tube, a catheter, or an application tip, may be attached to outlet  34  to aid in supplying fluid to a desired location, as will be described in detail herein. 
     If high pressure fluid accumulates in second chamber  660 , the pressure may exert a force in the second direction on membrane  730 , as described above, causing membrane  730  to move in the second direction. This force may be transmitted to piston  690 . Pressurized fluid in third chamber  666  may also result in an a force on ball bearing  750  in the second direction, as discussed above. These forces, together or separately, may cause regulator  40  to transition to a configuration in which third chamber  666  is sealed via ball bearing  750  and O-ring  760  (as shown in  FIG.  6 A ). The interactions described above may cause regulator  40  to iteratively transition between configurations in which third chamber  666  is sealed or unsealed. 
     Using the mechanisms described herein, regulator  40  controls a fluid pressure supply through output opening  654 . For example, the pressure is controlled by regulating the opposing forces of spring  740  on one side and spring  742  and fluid pushing against ball bearing  750  and membrane  730  on the other side. 
     The spring force of springs  740  and  742  are predetermined based on a desired pressure of a fluid that is to be dispersed and a desired rate at which the fluid is to be dispersed. For example, a spring with a lower rate (i.e., lowest amount of weight to compress a spring one inch) and higher compression/compressibility may achieve greater control over a pressure of fluid through output opening  654 . For example, according to an embodiment, regulator  40  may be designed to supply a hemostatic agent to a tissue at a pressure between approximately 25 and 100 PSI, and more particularly between approximately 40 to 60 PSI, and at a rate of approximately 5 to 15 liters per minute (LPM), and more particularly between 7 and 10 LPM. Regulator  40  provides a consistent pressure and flow of fluid from containment device  20 ,  20 ′. 
     As fluid is released from containment device  20 ,  20 ′, a pressure released from containment device  20 ,  20 ′ changes, for example, from a high pressure (approximately 850 PSI) to zero PSI when containment device  20 ,  20 ′ is empty. As the pressure in containment device  20 ,  20 ′ decreases, the pressure of fluid against ball bearing  750  and membrane  730  changes (e.g., lessens), reducing the force exerted in the second direction against spring  740 . Thus, as the pressure in containment device  20 ,  20 ′ decreases, the force of spring  740  causes a greater portion of hole  664  to be open, thereby providing a consistent rate of flow and pressure of the fluid supply at output  654 . However, a pressure of fluid from containment device  20 ,  20 ′ may be great enough to continue to exert forces on ball bearing  750  to provide sealing of chamber  666  via contact between ball bearing  750  and O-ring  760  when regulation of pressure is required. 
     The configuration shown in  FIG.  6 A  improves consistency of flow rate and output pressure of fluid. For example, membrane  730  is a silicone or other friction-reducing material. Silicone may remain flexible at low temperatures that may be present in regulator  40  due to high flow rates of fluid from containment device  20 ,  20 ′. That is, as actuator  680  moves along central axis A, there is no structure, such as an O-ring, in second chamber  660  between and in contact with actuator  680  and an inner surface of regulator wall  656  of body  650 . Such a structure would cause friction forces, making it difficult for actuator  680  to move, thereby decreasing the consistency at which a flow rate and output pressure of a fluid may be maintained. Thus, regulator  40  of  FIG.  6 A  minimizes friction forces when actuator  680  and piston  690  are moved along central axis A, providing improved consistency in the flow rate and output pressure of the fluid. 
       FIG.  7    illustrates another embodiment of a regulator  40 ′. Like elements in  FIG.  7    have like reference characters as those in  FIG.  6 A . As shown in  FIG.  7   , regulator  40 ′ has some different structures for regulating fluid flow and pressure. Further, regulator  40 ′ illustrates a snap-fit connection between capture cylinder  710 ′ and body  650 ′. For example, in the embodiment illustrated in  FIG.  7   , a regulator wall  656 ′ is snap fit together with a first wall  712 ′ of capture cylinder  710 ′. Additionally, and or alternatively, capture cylinder  710 ′ and body  650 ′ may be attached by adhesive, welding, or any other attachment mechanism known in the art. 
     As shown in  FIG.  7   , actuator  680 ′ interacts with a poppet  770 . Poppet  770  includes a body  772 , tabs  774 , and a protrusion  776 . One end of protrusion  776  is configured to contact actuator  680 ′. Protrusion  776  may be fixed to actuator  680 ′ by, example, adhesion or welding, to allow protrusion  776  and actuator  680 ′ to move together, as discussed in greater detail herein. Protrusion  776  extends through hole  664  in base  650 ′, and O-ring  760 ′ seals the space between hole  664  and tabs  774 . O-ring  760 ′ may be a resin or any other material known in the art (e.g., silicone) for fluidly sealing an opening. According to an example, a seal effective diameter where O-ring  760 ′ seals against the space between hole  674  and tabs  774  is approximately 0.05 inches to 0.14 inches, and preferably approximately 0.08 inches to 0.11 inches. As further shown in  FIG.  7   , body  772  extends into chamber  676  of pierce pin  670 , such that poppet  770  moves axially with respect to pierce pin  670 . For example, an outer wall  770   a  of poppet  770  has a diameter smaller than a diameter of inner wall  676   a  of chamber  676 . In this way, fluid may flow from input opening  652  to third chamber  666 . In the embodiment of  FIG.  7   , a spring  744  is provided in second chamber  660 , annularly disposed around cylindrical protrusion  662 , and causes actuator  680 ′ to move along central axis A, as will be described herein. 
     As in  FIG.  6 A , O-ring  760 ′ in  FIG.  7    is disposed adjacent inner wall  662   a  within third chamber  666  and lies adjacent to hole  664 . Tabs  774  are adjacent to O-ring  760 ′ on the side opposite hole  664 . O-ring  760 ′ may be fixed relative to tabs  774 . For example, tabs  774  may include grooves or alternative structures for receiving O-ring  760 ′. As will be described herein, tabs  774  and O-ring  760  are capable of sealing hole  664  from communication with third chamber  666  when O-ring  760 ′ is pressed against inner wall  662   a . Third spring  744  is disposed in second chamber  660  between, and in contact with both of, actuator  680 ′ and base  650 . Third spring  744  is sized to have an outer diameter smaller than an outer diameter of second chamber  660 , such that third spring  744  can expand and contract without creating friction forces between it and an outer wall of second chamber  660 . O-ring  760 ′ and tabs  774  are sized such that an outer diameter of each is less than the diameter of inner wall  662   a . In that way, when O-ring  760 ′ and/or tabs  774  are not sealing hole  664 , fluid flows between inner wall  662   a  and tabs  774  and/or O-ring  760 ′ and through hole  664  to chamber  660 . 
     An operation of regulator  40 ′ will now be described. Regulator  40 ′ of  FIG.  7    operates in a similar manner as described with reference to  FIG.  6 A . Regulator  40 ′ may have a first, sealed, configuration, shown in  FIG.  7   , in which O-ring  760 ′ presses against inner wall  662   a  and creates a seal such that fluid may not pass between O-ring  760  and inner wall  662   a  or between O-ring  760 ′ and tabs  774 . Thus, fluid may be unable to pass through hole  664 , Regulator  40 ′ may have a second, unsealed configuration (not shown), in which O-ring  760 ′ does not form a seal with inner wall  662   a  and/or tabs  774 , so that fluid may flow through hole  664 . 
     Spring  744  provides an opposing force to spring  740 . When one or more actuating devices  36   a ,  36   b  of application device  30  are manipulated, a pressure between second chamber  660  and an atmosphere surrounding application device  630  are equalized, thereby transitioning regulator  40 ′ from the sealed configuration of  FIG.  7    (where O-ring  760 ′ prevents passage of fluid through hole  664 ) to an unsealed configuration (where O-ring  760 ′ does not prevent passage of fluid through hole  664 ) and thus releasing fluid. As discussed herein, during the release of fluid, spring  740  presses piston  690  against membrane  730 , thereby pressing actuator  680 ′ toward pierce pin  670 . Movement of actuator  680 ′ toward pierce pin  670  causes poppet  770 , including O-ring  760 ′, to move in the first direction, toward pierce pin  670 . As poppet  770  moves in the first direction, a space is created between O-ring  760 ′ and inner wall  662   a . Fluid from containment device  20 ,  20 ′ may flow through the space between O-ring  760  and inner wall  662   a  and pass through hole  664 . Alternatively, tabs  774  of poppet  770  to loosen around O-ring  760 , thereby creating an opening between third chamber  666  and hole  664 . Fluid may move from containment device  20 ,  20 ′, through chamber  676  of pierce pin  670 , into second chamber  660 , and through output opening  654 , as shown by the flow path in  FIG.  7   . Although regulator  40 ′ is shown in a configuration in which fluid may not pass through output opening  654 , due to a seal between tabs  774  and O-ring  760 ′, the flow path in  FIG.  7    shows how fluid would flow when tabs  774  are loosened around O-ring  760 ′. The configuration shown in  FIG.  7    similarly improves consistency of flow rate and output pressure of fluid. The configuration of  FIG.  7   , in particular, may reduce a sealing diameter between O-ring  760 ′, tabs  774 , and inner wall  662   a . This decreased diameter may allow for increased sealing, which may prevent fluid from passing through hole  664  when such passage would cause a deviation from the desired regulated pressure. As discussed with regard to  FIGS.  6 A- 6 C , movement of membrane  730  and actuator  680 ′ may allow for dynamic adjustment of an amount of fluid that may pass through hole  664  and exit output opening  654 . 
     As discussed herein, membrane  730  reduces a friction between actuator  680  and body  650 . This reduced friction provides more freedom of movement between elements, thereby improving the consistency of the output pressure and flow rate of the fluid. As also described herein, throughhole  686  may be provided in actuator  680 . Throughhole  686  may assist in providing a consistent pressure and consistent rate of fluid flow from output  654 . 
       FIGS.  11 A and  11 B  show a further exemplary regulator  40 ″, which may have any of the properties of regulators  40  or  40 ′, described above, and which may be used in conjunction with delivery system  10 . Although all of the features of regulator  40 ″ corresponding to those of regulator  40  may not be discussed in the description below, it will be appreciated that those features may be present in regulator  40 ″, unless explicitly stated otherwise. Like reference numbers denote corresponding structures.  FIG.  11 A  shows regulator  40 ″ with third chamber  666  sealed, and  FIG.  11 B  shows regulator  40 ″ with third chamber  666  unsealed. 
     Regulator  40 ″ may include an X-ring seal  760 ″ (e.g., a quad-ring seal). X-ring seal  760 ″ may have an approximately X-shaped cross-section with rounded corners. X-ring seal  760 ″ may have a central circumference and four protrusions  762 ,  764 ,  766 ,  768  extending radially outward from the central circumference. Alternatively, X-ring seal  760 ″ may have other suitable numbers of protrusions. X-ring seal  760  may have a cross-section similar to an asterisk where X-ring seal  760 ″ has more than four protrusions. 
     X-ring seal  760 ″ may be fitted against inner wall  662   a  of cylindrical protrusion  662 . For example, inner wall  662   a  may have a groove or grooves in which X-ring seal  760 ″ may be received. Protrusions  764 ,  766 , and  768  may each be in contact with one or more surfaces of inner wall  662   a . For example, as discussed below, surfaces  662   aa ,  662   ab  of inner wall  662   a  may form a corner in which X-ring seal  760 ″ may be received. Each of surfaces  662   aa  and  662   ab  may face third chamber  666 . 
     As compared with an O-ring, X-ring seal  760 ″ provides additional points of contact with inner wall  662   a . When points of contact are referred to herein, it will be appreciated that contact between X-ring seal  760 ″ and inner wall  662   a  may extend over more than just a single point and may include a larger (and possibly continuous) area of contact. 
     X-ring seal  760 ″ may provide four points of contact with inner wall  662   a . First surface  662   aa  of inner wall  662   a  may be perpendicular or approximately perpendicular to axis A. Second surface  662   ab  of inner wall  662   a  may be parallel or approximately parallel to axis A. First surface  662   aa  and second surface  662   ab  may meet at a corner. Protrusion  768  may contact first surface  662   aa  at point W (shown in the inset of  FIG.  11 A ). Protrusion  764  may contact second surface  662   ab  at point X. Protrusion  766  may have points of contact with both second surface  662   ab  (at point Y) and first surface  662   aa  (at point Z). In contrast, an O-ring would provide only one point of contact with first surface  662   aa  and one point of contact with second surface  662   ab . Therefore, X-ring seal  760 ″ provides more redundant sealing than an O-ring by providing additional, separate points of contact. Points W, X, Y, and Z may be separated from one another by a gap or space. Even were one or more points of contact to be breached, other points of contact may provide sealing. X-ring seal  760 ″ could maintain sealing even with two (or three) points of contact broken, while an O-ring with two points of contact broken would fail to provide a seal. Furthermore, having separated points of contact W, X, Y, Z may provide for suction effects, increasing sealing. 
     A surface area of each of contacts W, X, Y, Z between X-ring seal  760 ″ and inner wall  662   a  may be smaller than a surface area of each contact between an O-ring and inner wall  662   a  would be. As compared to O-ring  760 , the protrusions  762 ,  764 ,  766 ,  768  of X-ring seal  760 ″ may provide narrower, more focused points of contact between X-ring seal  760 ″ and inner wall  662   a . A radius of curvature of each of protrusions  762 ,  764 ,  766 , and  768  may be less than a radius of curvature of an O-ring, producing more defined points of contact. 
     When ball bearing  750 ″ (or another type of body) presses against and contacts X-ring seal  760 ″ (at at least one point), these more focused contacts may provide for increased sealing, as compared to an O-ring. Because, as compared to an O-ring, the same (or similar) force is exerted by ball bearing  750 ″ over a smaller area, a greater pressure may be exerted on protrusions  762 ,  764 ,  766 ,  768  of X-ring seal  760 ″, which may provide for increased sealing. Due to the shape of protrusions  762 ,  764 ,  766 ,  768 , pressure exerted at each point of contact between X-ring seal  760 ″ and ball bearing  750 ″ or inner wall  662   a  may be greater than corresponding pressures of an O-ring. As discussed in further detail below, even when ball bearing  750 ″ exerts a relatively smaller force (e.g., when pressure has dropped in containment device  20 ,  20 ′), X-ring seal  760 ″ may provide a more reliable seal against ball bearing  750 ″, as compared to an O-ring. 
     X-ring seal  760 ″ may have a durometer measurement that is chosen to result in the desired sealing properties, described below. For example, the durometer measurement may be 70 or approximately 70. Durometer measurements of seal  760 ″ may range from approximately 55 to approximately 90, and, more particularly, from approximately 70 to approximately 80. X-ring seal  760 ″ may be formed of a material that enables X-ring seal  760 ″ to retain elastomeric properties in conditions such as those which may be present in regulator  40 ″ during operation of delivery system  10  (e.g., in cold temperatures such as those of approximately −50 degrees C. (e.g., between approximately −40 degrees C. and approximately −60 degrees C.)). For example, X-ring seal  760 ″ may be entirely formed from or may include silicone, rubbers (such as nitrile rubbers), and/or polyurethane. An X-ring seal having the qualities of X-ring seal  760 ″ may be used as an alternative to O-ring  760  or  760 ′ in regulators  40 ,  40 ′, above. O-ring  760  or  760 ′ may have durometer and/or material features of X-ring seal  760 ″, described above. 
     Regulator  40 ″ may also include ball bearing  750 ″. A material forming ball bearing  750 ″ (or portions thereof) may have a durometer measurement chosen to achieve the desired sealing between ball bearing  750 ″ and X-ring seal  760 ″, described below. For example, a durometer measurement of ball bearing  750 ″ may be 90 or approximately 90. A durometer measurement of ball bearing  750 ″ may range from approximately 80 to approximately 90. A composition of ball bearing  750 ″ may be such that ball bearing  750 ″ does not freeze to other components of regulator  40 ″ when exposed to solid, liquid, and/or freezing gaseous carbon dioxide. For example, ball bearing  750 ″ may be formed entirely of or may include rubber, silicone, nitrile, polyurethane, steels, and/or ceramics. A ball bearing having the characteristics of ball bearing  750 ″ may be used as an alternative to ball bearing  750  in regulator  40 , above, either in conjunction or separately from X-ring seal  760 ″ (i.e., regulator  40  may use structures having qualities of either or both of X-ring seal  760 ″ and ball bearing  750 ″). 
     X-ring seal  760 ″ may have a 1/16-inch cross section (measured along a line B, shown in the insert of  FIG.  11 A ), a 5/64- 7/64-inch internal diameter (measured along a line C, shown in  FIG.  11 A ), and a 13/64-1 5/64-inch outer diameter (measured along a line D, shown in  FIG.  11 A ). X-ring seal  760 ″ may have a cross section between approximately 1/32 inch and approximately 3/32 inch, an internal diameter between approximately 1/16 inch and approximately ⅛ inch, and an outer diameter between approximately 6/32 inch and approximately ⅛ inch. Ball bearing  750 ″ may have a diameter of approximately 0.188 inches. Similar or alternative sizes may be used, either in regulators  40 ″ for use with system  10  or regulators  40 ″ for use in alternative systems. A size of ball bearing  750 ″ may not exceed a diameter of third chamber  666  and may be greater than an internal diameter of X-ring seal  760 ′. For example, ball bearing  750 ″ may have a diameter between 0.125 inches and 0.25 inches. For example, a regulator  40 ″ used with an alternative system may have different dimensions than a regulator  40 ″ used with system  10 . 
     An operation of regulator  40 ″ will now be described. Regulator  40 ″ of  FIGS.  11 A- 11 B  operates in a similar manner as described with reference to  FIGS.  6 A- 6 C . Operation of regulator  40 ″ will therefore not be separately described in detail. Differences between an operation of regulator  40  and regulator  40 ″ are described below. 
     Like ball bearing  750  and O-ring  760 , ball bearing  750 ″ and X-ring seal  760 ″ may be capable of sealing hole  664  from communication with third chamber  666 .  FIG.  11 A  shows regulator  40 ″ with third chamber  666  sealed so that fluid cannot pass through hole  664 . In certain configurations of regulator  40 ″, (as shown in  FIG.  11 A ), ball bearing  750 ″ may exert a force against protrusion  762  of X-ring seal  760 ″. Such configurations are described above, with respect to regulator  40 . 
     As discussed above, a seal between ball bearing  750 ″ and X-ring seal  760 ″ may be stronger than a seal between a ball bearing (such as ball bearing  750 ) and an O-ring seal (such as O-ring  760 ). As discussed above, protrusion  762  has a smaller radius of curvature than O-ring  760 . Therefore, for a given force, ball bearing  750 ″ exerts a larger pressure on protrusion  762 , which provides for tighter sealing between X-ring seal  760 ″ and ball bearing  750 ″. 
     As ball bearing  750 ″ presses against protrusion  762 , second, third, and fourth protrusions  764 ,  766 ,  768 , respectively, may press against surfaces  662   aa  and  662   ab  at points W, X, Y, and Z. As discussed above, protrusions  664 ,  666 , and  668  may provide redundant sealing due to the increased number of contact portions. 
     The increased sealing provided by ball bearing  650 ″ and X-ring seal  660 ″ may increase performance of regulator  40 ″. For example, increased sealing may prevent fluid from leaking through hole  664  when a pressure should be regulated and third chamber  666  should be sealed. Furthermore, as described above with respect to regulator  40 , pressure of fluid released from containment device  20 ,  20 ′ may change over time. In particular, pressure from containment device  20 ,  20 ′ may decrease over time. As pressure from containment device  20 ,  20 ′ decreases, a force exerted by the pressurized fluid, in the second direction, on ball bearing  750 ″ may decrease. However, to achieve the desired, regulated pressure, sealing of chamber  666  may be required. When an O-ring is used, the decreasing force exerted by ball bearing  750 ″ may result in insufficient pressure to seal chamber  666 . Because of the smaller area/volume of protrusion  762 , a smaller force may be required in order to exert a sealing pressure on X-ring seal  760 ″. Therefore, as pressure from containment device  20 ,  20 ′ decreases, X-ring seal  760 ″ may maintain sealing of chamber  666  when desired, while an O-ring may less consistently maintain sealing under similar circumstances. The increased sealing accomplished by X-ring seal  760 ″ may result in increased performance of regulator  40 ″. 
     Although many of the features of regulator  40 ,  40 ′,  40 ″ are described as cylindrical, the shape of the elements are not limited thereto. Rather, the features may be any shape suitable for regulator  40 ,  40 ′,  40 ″ to properly regulate a fluid dispersion from containment device  20 ,  20 ′. Moreover, unless described otherwise, the structural elements of application device  30  and/or regulator  40 ,  40 ′,  40 ″ may be any material known in the art, including but not limited to a metal alloy, a ceramic, and/or a resin. 
     With reference to  FIG.  12   , a relief valve  62  according to an embodiment is shown. Relief valve  62  is positioned along second fluid path  48  between membrane regulator  44  and container  100  (housing  107  of container  100  is not shown in  FIG.  12    for ease of understanding) to vent propellant fluid from containment device  20 ,  20 ′ if, e.g., one or more of membrane regulator  44  or regulator  40  fails. For example, relief valve  62  includes a burst disc  62   a  that may rupture when a pressure at relief valve  62  is greater than a final, predetermined regulated pressure, e.g., a pressure of the propellant fluid after passing through properly functioning and properly adjusted regulator  40  and membrane regulator  44 . A pressure at which burst disc  62   a  will burst may be approximately 20 PSI to 150 PSI, more preferably approximately 50 PSI to 70 PSI, and more preferably approximately 60 PSI. It will be understood that the burst pressure of burst disc  62   a  may be modified, or a burst disc  62   a  having a different burst pressure may be used, based on the desired output pressure from membrane regulator  44 . It will also be understood that relief valve  62  is not limited to burst disc  62   a , and may be any relief valve suitable for venting propellant fluid at a pressure greater than a desired output pressure such as, e.g., a pilot valve or the like. It will further be understood that relief valve  62  is not limited to being positioned as shown in  FIG.  12   , and may be positioned at any location between containment device  20 ,  20 ′ and outlet  34  to prevent propellant fluid and/or a mixture of propellant fluid and material from being released from application device  30  above a desired pressure. Additionally, or alternatively, relief valve  62  may be placed at any position along a fluid path to release fluid pressure. 
     Container  100  according to an embodiment is shown in  FIG.  13   . As discussed above, container  100  may contain a powder, a fluid, or other substance to be mixed with the propellant fluid from containment device  20 ,  20 ′ and dispensed through outlet  34  to catheter  190 . Container  100  includes an inner chamber  106  defined by housing  107  of container  100  and a surface  109  of application device  30 , which defines a bottommost surface of inner chamber  106 . Inner chamber  106  contains the powder, fluid, or other substance. According to an example, housing  107  is a clear material to visualize inner chamber  106 , but the invention is not limited thereto. Propellant fluid enters container  100  from second fluid path  48  via a chamber inlet  102  (see  FIGS.  14 A and  14 B ). Propellant fluid passes through filters  104  provided in filter holes  104   a  in bottommost surface  109  of inner chamber  106 , which contains the powder or fluid, of container  100  (as described above, propellant fluid enters container  100  via the plurality of sixth pathway O via the filter holes  104   a ). While two filter holes  104   a  are shown in  FIG.  13   , container  100  may include any number of filter holes  104   a , such as one to four filter holes  104   a . Filters  104  may be sized to have holes approximately 25 to 50 microns in diameter to prevent powder or fluid from inner chamber  106  from passing from inner chamber  106  back through second fluid path  48 , which may clog and/or contaminate application device  30 . 
     With continued reference to  FIG.  13   , inner chamber  106  includes a chamber relief valve  108 . Chamber relief valve  108  may be similar to relief valve  62  and may be, e.g., a burst disc or any other pressure relief valve known in the art. As with relief valve  62 , chamber relief valve  108  relieves pressure when a pressure within application device  30 , and specifically chamber  106 , is greater than the final regulated pressure e.g., relief valve  108  burst pressure may be approximately 20 PSI to 150 PSI, more preferably approximately 50 PSI to 70 PSI, and more preferably approximately 60 PSI. While chamber relief valve  108  is provided in the bottommost surface of inner chamber  106 , the location of relief valve  108  is not limited thereto. While not shown, relief valve  108  may vent propellant gas through a lumen provided in bottommost surface  109  of inner chamber  106 . 
     A tube  110 , such as a hypotube, extends from and generally perpendicular to bottommost surface  109  of inner chamber  106  toward a topmost surface of inner chamber  106 , but it not limited to this configuration. As shown in  FIGS.  12  and  13   , a slot  112  is provided in, and through a wall of, tube  110  near the bottommost surface of inner chamber  106 . Slot  112  is fluidly connected to a chamber outlet  114  (see  FIGS.  14 A and  14 B ), which connects to outlet  34 , and allows a mixture of propellant fluid and the fluid or powder from inner chamber  106  to be dispensed from inner chamber  106  to outlet  34 . Alternatively, or additionally, there may exist a plurality of slots  112  circumferentially arranged about a longitudinal axis A of tube  110 , which may provide additional dispensing outlets from inner chamber  106 . According to another example, slot  112  may be one or more circular (or other-shaped) holes provided in tube  110 . The shape, number, and arrangement of slot  112  may aid in dispensing an appropriate amount of the propellant fluid and powder mixture from inner chamber  106  to chamber outlet  114 , and the number of slots  112  may change according to a desired output. According to an example, the area of slot(s)  112  (either the area of a single slot  112  or the sum of the area of all slots  112 ) may be approximately 0.0025 square inches to 0.030 square inches, and more preferably 0.0046 square inches to 0.025 square inches, depending on the desired delivery rate of the propellant fluid and material mixture. Further, slot(s)  112  may be approximately 0.05 to 0.2 inches from filter holes  104   a.    
     Container  100  may contain one or more spacers  216  (see  FIG.  12   ) extending from the bottommost surface of inner chamber  106 . Spacers  216  may alter the movement of material and/or propellant fluid through container  100 , as will be described in greater detail below. It will be understood that container  100  may be formed without spacers  216 . 
     As shown in  FIGS.  13 ,  14 A, and  14 B , a ring or wheel-shaped attachment member  116  includes spokes  116   a , is attached to and extends from a sheath  118  (described in detail below) and is attached to an inner surface of housing  107 . Attachment member  116  connects sheath  118  to housing  107 , such that a movement of housing  107  causes concurrent movement of sheath  118 . Attachment member  116  (and spacers  216  in those embodiments that include spacers  216 ) may fill one or more voids within inner chamber  106  to alter the movement of materials therein. For example, attachment member  116  and spacers  216  may fill voids that would prevent material from properly mixing with the material located within inner chamber  106  and/or prevent the mixture from being appropriately dispensed through slot  112 . Attachment member  116  and spacers  216  may further create new and/or additional pathways for the combination of propellant fluid and materials to take through inner chamber  106 . For example, as shown in  FIGS.  14 A and  14 B , spaces exist between the spokes  116   a  of attachment member  116 , allowing propellant fluid and material to flow therebetween, while also changing the flow pattern of fluids and materials within container  100 . These additional pathways may improve mixing of the propellant fluid with the materials and may ensure a more consistent amount of material is output from inner chamber  106 . 
     With continued reference to  FIG.  13   , sheath  118  is provided on an outer surface of and coaxial with tube  110 . Further, a conical member  120  is adjacent the topmost surface of inner chamber  106 , and may be integrally formed with or otherwise fixed to housing  107 . In a closed configuration, e.g., when inner chamber  106  is fluidly uncoupled from application device  30  as shown in  FIG.  14 A , sheath  118  covers and seals slot  112  and conical member  120  extends into and seals a distalmost end  110   a  of tube  110 . This closed configuration prevents the material provided in inner chamber  106  from being contaminated and prevents the material from being dispensed before the physician is prepared to dispense the material. In contrast, when inner chamber  106  is in an open configuration and inner chamber  106  is fluidly coupled with application device  30 , as shown in  FIG.  14 B , slot  112  is exposed and distalmost end  110   a  of tube  110  is open to inner chamber  106 . The open configuration allows a mixture of propellant fluid and material in inner chamber  106  to be dispensed through slot  112  to outlet  34 . 
     As further shown in  FIG.  14 A , one or more cams  122  are attached to an inner surface or an outer surface of housing  107  and are disposed in and movable along a cam shaft  124 . Cam shaft  124  is ramp shaped and sloped downward from inner chamber  106  toward chamber inlet  102 . In the closed configuration, achieved by twisting container  100  in the direction of arrow Y in  FIG.  14 A , cam  122  is disposed at a first end  124   b  of cam shaft  124 , which is positioned near inner chamber  106 . In the open configuration, achieved by twisting container  100  in the direction of arrow X in  FIG.  14 B , cam  122  is disposed at a second end  124   a  of cam shaft  124 , which is opposite first end  124   b , as shown in  FIG.  14 B . When container  100  is twisted in the direction of arrow X, housing  107  moves upward, as shown in  FIG.  14 B . Since attachment member  116  is attached to the inner side of housing  107 , and since attachment member  116  is also attached to sheath  118 , twisting container  100  in the direction of arrow X causes sheath  118  to also move upward and expose slot  112 . Further, since conical member  120  is also attached to the inner side of housing  107 , moving container  100  upward exposes distalmost end  110   a  of tube  110 . 
     To attach housing  107  to application device  30 , cam  122  is placed into the U-shaped groove  124   c  of cam shaft  124 . Housing  107  may then be twisted as described above in the direction of arrow Y to close container  100 , or in the direction of arrow X (from the closed position) to open container  100 . According to an example, one or more O-rings and/or sealing members may be provided between housing  107  and application device  30  to assist in fluidly sealing housing  107  to application device  30 . 
     A method of operating medical device  10  will now be explained. Application device  30  and/or containment device  20 ′ may be packaged with container  100  attached thereto or, alternatively, may allow for container  100  to be attached to application device separately. After container  100  is attached to application device  30 , containment device  20 ′ may be attached to inlet  42 . For example, containment device  20 ′ may be attached to application device  30  using locking mechanism  50 . According to an example, containment device  20 ′ may be placed on a surface of piston  58  when lever  52  is in a first position, as shown in  FIG.  4   . Lever  52  is subsequently pushed toward handle  31  about pivot axis R, urging containment device  20 ′ towards inlet  42  via attachment device  38 . A pierce pin (not shown) on application device  30  breaks a seal (not shown) on containment device  20 ′, causing containment device  20 ′ and application device  30  to be in fluid communication. Lever  52  is held in a locked position when cam  57  rests in locking notch  56 , which maintains a position of lever  52  adjacent handle  31  and maintains containment device  20 ′ toward inlet  42 . 
     With reference to  FIG.  2   , actuation of first actuator  36   a  and second actuator  36   b  may independently control release of propellant fluid through application device  30 . For example, actuation of second actuator  36   b  causes propellant fluid to travel along first fluid path  46 , i.e., through first pathway J, second pathway K, and fourth pathway L to outlet  34 , as shown in  FIG.  3   . Use of this first fluid path  46  allows a user to purge material from outlet  34  and/or catheter  190 , if catheter  190  is attached to application device  30  (see  FIG.  2   ). The pressure of propellant fluid released in application device  30  may be controlled as described herein with reference to regulator  40 . 
     With reference to  FIGS.  14 A and  14 B , a user moves container  100  from a first position ( FIG.  14 A ) to a second position ( FIG.  14 B ) by turning container  100  in the direction X. As shown in  FIG.  14 B , slot  112  is exposed to inner chamber  106 . Further, in the second position, the intermediate portion, including sixth pathways O and seventh pathway O′, is fluidly coupled with the distal portion, including eighth pathway P, and the proximal portion, including first, third, and fifth pathways J, M, and N, of the second fluid path  48 . Subsequently, a user actuates second actuation device  36   a , causing propellant fluid to travel through the proximal portion of second fluid path  48  and into inner chamber  106 . The propellant fluid mixes with a material, such as powder, in container  100 , and the material and propellant mixture is expelled through slot  112  into the distal portion of second fluid path  48 . The propellant fluid and material mixture exits application device at outlet  34 , traveling down catheter  190  to distal end  193  (see  FIG.  35   ). The user is able to direct the mixture to a target location by moving distal end  193  to different locations. 
     Referring to  FIGS.  15  and  16   , device  100 ′ for fluidizing and delivering a powdered agent (e.g., a powdered therapeutic agent) to a site within a living body (e.g., a target site) according to another embodiment. The device (e.g., container)  100 ′ according to an example further comprises an overtube (e.g., a sheath)  118 ′ movably mounted over a portion of the tube  110  so that the overtube  118 ′ may be moved along a length of the tube  110  to extend over the slot  112 , controlling a size of an opening of the slot  112 . Testing has shown that increasing the slot size increases the powder delivery rate while decreasing the slot size decreases the powder delivery rate. The overtube  118 ′ is movable relative to the tube  110  from an initial configuration, in which the overtube  118 ′ at least partially covers the slot  112  toward an open configuration, in which the overtube  118 ′ is moved along a length of the tube  110  to gradually increase the size of the slot  112  during the course of the treatment procedure so that the rate of delivery of the fluidized powder delivery may be maintained above a threshold level (e.g., be held substantially consistent over time) even as a volume of the powdered agent within the canister  107 ′ decreases as the powder is dispensed. It will be understood that a fluidized powder/material includes, but is not limited to, a powder/material that acquires the characteristics of a fluid by passing a propellant fluid (such as a gas) with in or through it, and also an agitized powder/material which is a material that follows a propellant fluid or is pushed by a propellant fluid. 
     According to an embodiment, a target delivery rate may be, for example, greater than 1 gram for every 5 seconds of delivery. The device  100 ′ may provide the best delivery results when the canister  107 ′ is approximately 45% to 80% filled with the powdered agent. For example, at 80% fill the target rate may be sustained for 30 delivery seconds. This delivery rate is also dictated by the amount of gas that the device  100 ′ may use for delivery. By gradually increasing the size of the slot  112  through which the fluidized powder mixture may exit the canister  107 ′, the delivery rate may be maintained (e.g., past 30 delivery seconds) even as the volume of the powdered agent within the canister  107 ′ decreases. 
     The canister  107 ′ in this embodiment extends longitudinally from an open first end  119  to a closed second end  121  to define the inner chamber  106 ′, which is configured to receive the powdered agent therein. A lid (e.g., a surface)  109 ′ is coupled to the first end  119  to enclose the inner chamber  106 ′ and prevent the powdered agent and/or gas from leaking from the inner chamber  106 ′. In one embodiment, the lid  109 ′ is received within the first end  119  and coupled thereto. The inlet (e.g., filter hole)  104 ′ and/or an outlet (via slot  112 ) in this embodiment are configured as openings extending through the lid  109 ′. It will be understood by those of skill in the art, however, that the inlet  104 ′ and the outlet may have any of a variety of configurations so long as the inlet  104 ′ and the outlet are connectable to a gas source and a delivery member, respectively, for supplying a high flow gas to the powdered agent to fluidize the powdered agent and deliver the fluidized powder mixture to the target site. For example, the inlet  104 ′ may be coupled to a connecting member (e.g. second fluid path)  48 ′ which connects the gas source to the inlet  104 ′. In an embodiment, gas may be supplied to the canister  107 ′ at a pressure ranging from between 5 and 20 psi and/or a flow rate of 8-15 standard liters per minute. The outlet in this embodiment is coupled to catheter  190 ′ sized, shaped and configured to be inserted through a working channel of a flexible endoscope to the target site within a living body. In one example, catheter  190 ′ may have an inner diameter between 0.065 inches and 0.11 inches. In another embodiment, the inlet  104 ′ and the outlet may extend through a portion of the canister  107 ′. 
     The tube  110  extends from a first end  128  connected to the outlet to a second end (e.g., distalmost end)  110   a ′ extending into the interior space  106 ′. As described above, the tube  110  in  FIGS.  15  and  16    also includes a slot  112 , which extends through the wall of the tube  110 . The slot  112  in this embodiment is positioned proximate the first end  128  so that the fluidized powder mixture may exit the interior space  106 ′ of the canister  107 ′ via one of second end  110   a ′ of the tube  110  and the slot  112  proximate the first end  128 . 
     The overtube  118 ′ is movably mounted over a portion of a length of the tube  110 . The overtube  118 ′ is movable relative to the tube  110  so that, as the overtube  118 ′ moves over the tube  110 , an area of the slot  112  covered by the overtube  118 ′ is varied to control a size of a portion of the slot  112  exposed to the interior space  106 ′ and through which the fluidized powder mixture may exit the interior space  106 ′ of the canister  107 ′. For example, in an initial configuration, the overtube  118 ′ extends over the entire slot  112  so that the slot  112  is completely covered, preventing any fluidized powder mixture from exiting therethrough. During the course of treatment of the target site, however, the overtube  118 ′ may be moved relative to the tube  110  to increase the size of the portion of the slot  112  exposed and through which the fluidized powder may exit to maintain the delivery rate of the fluidized powder mixture at a desired level (e.g., above a threshold delivery rate). For example,  FIG.  16    shows the slot  112  partially covered via a portion of the overtube  118 ′ and  FIG.  15    shows the slot  112  entirely exposed. Although the embodiment describes an initial configuration in which the entire slot  112  is covered, it will be understood by those of skill in the art that, in an initial configuration, the overtube  118 ′ may have any of a variety of positions relative to the slot  112 , so long as the size of the slot  112 , through which the fluidized powder may exit, is increased during the course of treatment as the powder in the canister  107 ′ is dispensed. 
     It will also be understood by those of skill in the art that the overtube  118 ′ may be moved relative to the tube  110  via any of a variety of mechanisms. In one embodiment, the overtube  118 ′ may be connected to a stabilizing ring  116 ′ which extends, for example, radially outward from the overtube to an interior surface of the canister  107 ′ to fix a position of the overtube  118 ′ relative to the canister  107 ′. The canister  107 ′ and the tube  110  in this example are rotatably coupled to one another so that, when the canister  107 ′ is rotated relative to the tube  110 , the overtube  118 ′ correspondingly rotates about the tube  110  while also moving longitudinally relative to the tube  110  to increase (or decrease, depending on the direction of rotation) a size of the slot  112  through which the fluidized powder mixture may exit. In one example, the lid  109 ′, from which the tube  110  extends, includes cam paths  124  extending along a partially helical path, within which an engaging feature (e.g., protrusion  122  in  FIGS.  14 A and  14 B ) of the canister  107 ′ rides so that, as the canister  102  and, consequently, the overtube  118 ′ are rotated relative to the lid  109 ′ and the tube  110 , the overtube  118 ′ moves longitudinally relative to the tube  110 . As would be understood by those skilled in the art, the cam paths  124  and the corresponding engaging features of the canister  107 ′ function similarly to a threaded engagement between the canister  107 ′ and the lid  109 ′ to achieve the desired relative movement between the overtube  118 ′ and the tube  110 . 
     Although the embodiment describes the size of the portion of the slot  112  available for fluidized powder mixture to exit as controlled via the overtube  118 ′, the size of the slot  112  may be controlled via any “door” having any of a variety of structures and geometries so long as the “door” may be gradually opened during the course of a treatment procedure to maintain a desired flow rate of therapeutic agent out of the canister  107 ′. Movement of the overtube  118 ′ or any other “door” may be actuated mechanically, e.g., by physically twisting the overtube  118 ′, or may be actuated pneumatically by the flow of gas. In addition, although the embodiment shows and describes a single slot  112 , the tube  110  may include more than one slot  112 , which may be covered and/or exposed, as desired, via any of a number of door mechanisms, as described above. 
     According to an example method using the device  100 ′, the canister  107 ′ is filled with a powdered agent such as, for example, a hemostatic agent, prior to assembly of the device  100 ′. Upon filling the canister  107 ′ with a desired amount of powdered therapeutic agent, the canister  107 ′ is assembled with the lid  109 ′ to seal the powdered agent therein. The inlet  104 ′ is then coupled to the gas source via, for example, the connecting member  48 ′ and the outlet is coupled to the catheter  190 ′. The catheter  190 ′ is then inserted to the target site within the living body (e.g., through a working channel of a delivery device such as, for example, an endoscope). High flow gas is introduced into the interior space  106 ′ of the canister  107 ′ to form the fluidized powder mixture. The user may depress a trigger or other controller to spray the fluidized mixture and to deliver the fluidized mixture to the target are (e.g., a bleeding site) to provide treatment thereto. As the fluidized powder mixture is being delivered to the target site, the user may physically rotate the canister  107 ′ relative to the tube  110  to increase the size of the slot  112  through which the fluidized mixture is exiting the interior space  106 ′ to maintain a desired flow level. Alternatively, if a trigger is being used to control delivery of the fluidized powder mixture, when the trigger is depressed, a pneumatic cylinder or motor may be operated to rotate and move the lid  109 ′ relative to the canister  107 ′ so that a larger cross-sectional area of the slot  112  is exposed, increasing the size of the slot  112  through which the fluidized mixture may exit the interior space. Thus, as a volume of the powdered agent within the canister  107 ′ is decreased, the cross-sectional area of the slot  112  that is exposed is increased to maintain a substantially constant delivery rate of the fluidized powder mixture. Alternatively, sensors may detect a flow rate and automatically control the opening of the slot  112  to ensure that a desired flow rate is maintained. 
     A device  200  according to another embodiment of the present disclosure, shown in  FIG.  17   , is substantially similar to the device  100 ′ as described above unless otherwise indicated. The device  200  comprises a canister  202  defining an interior space  204  within which a powdered agent is received. Similarly to the device  100 ,  100 ′, the interior space  204  is enclosed via a lid  222  coupled thereto so that the powdered agent contained within the interior space  204  forms a fluidized powder mixture when the interior space  204  is supplied with a high flow gas via an inlet  206 . The fluidized powder mixture exits the interior space  204  via an outlet  208  to be delivered to a target site within a patient during treatment. To maintain a desired delivery rate as the volume of the powdered agent in the interior space  204  decreases during the course of treatment, the lid  222  includes a turbulator plate  230 . As gas passes through the turbulator plate  230 , the turbulator plate  230  vibrates and/or rattles to prevent, or at least reduce, settling of the powdered agent contained within the canister  202 . Without the turbulator plate  230 , during the course of treatment, some powdered agent would otherwise settle into an equilibrium state, resisting fluidization and making it difficult to maintain a desired delivery rate of the therapeutic agent. 
     Similarly to the canister  107 ′, the canister  202  extends longitudinally from an open first end  218  to a closed second end  220  to define the interior space  204 . The lid  222  is coupled to the first end  218  to enclose the interior space  204  and contain the powdered agent therein. The inlet  206  and the outlet  208  are configured as openings extending through the lid  222  in communication with the interior space  204 . Although not shown, similarly to the device  100 ′, the outlet  208  includes a tube extending therefrom and into the interior space  204  to allow the fluidized powder mixture to exit via the tube and the outlet  208 . 
     The turbulator plate  230  in this embodiment extends along a portion of the lid  222  which faces away from the interior space  204 . In this embodiment, the turbulator plate  230  includes an opening  232  extending through a wall  234  thereof, the opening  232  being configured to be connected to a gas source via, for example, a connecting element  224 . The turbulator plate  230  extends along the lid  222  so that the opening  232  is in communication with the inlet  206 . Thus, gas passes through the turbulator plate  230  and into the interior space  204  via the inlet  206 . An interior  236  of the turbulator plate  230  includes a plurality of structures  238  such as, for example, ribs, bumps or bosses, which cause the flow of gas therethrough to be turbulent, imparting a vibratory response in the turbulator plate  230 . The vibration in turn prevents the powdered agent from settling on the lid  222 . Thus, the flow of gas through the turbulator plate  230  and into the interior space  204  causes both the vibration of the turbulator plate  230  and the fluidization of the powered agent within the canister  202 . A magnitude of the vibration may be controlled via control of the rate at which gas is passed through the turbulator plate  230  as would be understood by those skilled in the art. In this embodiment, the magnitude of vibration of the turbulator plate  230  is held constant over time, for as long as the user is depressing a trigger to feed gas to the canister  202 . The fluidized powder agent exits the canister  202  via the outlet  208 , which is not in communication with the interior  236  of the turbulator plate  230 . The outlet  208  in this embodiment is coupled to a delivery catheter  226  for delivering the fluidized powder mixture to the target site. 
     In an alternate embodiment, as shown in  FIG.  18   , a device  200 ′ is substantially similar to the device  200  described above, unless otherwise indicated. In this embodiment, a turbulator plate  230 ′ extends along a portion of a lid  222 ′, which encloses an interior space  204 ′ defined via a canister  202 ′, and includes a first opening  232 ′ and a second opening  240 ′ extending through a wall  234 ′ thereof. Neither the first opening  232 ′ nor the second opening  240 ′ are in communication with an inlet  206 ′ and an outlet  208 ′ of the device  200 ′. Each of the inlet  206 ′ and the first opening  232 ′ are configured to be connected to a gas source for supplying gas to the interior space  204 ′ and the turbulator plate  230 ′, respectively. Each of the inlet  206 ′ and the first opening  232 ′ is connected to the same or different gas sources. 
     Gas supplied to the turbulator plate  230 ′ via the first opening  232 ′ passes through the turbulator plate  230 ′ and exits the turbulator plate  230 ′ via the second opening  240 ′. Gas may, for example, be supplied to the turbulator plate  230 ′ at a constant rate while the powdered agent is being fluidized and delivered to the target site to maintain a constant magnitude of vibration. Alternatively, the flow of gas supplied to the turbulator plate  230 ′ may be changed over time, or intermittently, to change a magnitude of vibration, as desired, to optimize the rate of delivery of the fluidized powder mixture. It will be understood by those of skill in the art, however, that the function of the turbulator plate  230 ′ remains otherwise the same as the device  200 , keeping the powdered agent from settling on the lid  222 ′. 
     As shown in  FIGS.  19  and  20   , a device  300  according to another embodiment of the present disclosure is substantially similar to the devices  100 ′,  200 , unless otherwise indicated. The device  300  comprises a canister  302  defining an interior space  304  within which a powdered agent (e.g., hemostatic agent) is received and fluidized via a high flow gas for delivery to a target site (e.g., bleeding site) for treatment. The interior space  304  is enclosed via a lid  322  attached to an open end of the canister  302  and gas is supplied to the interior space  304  via an inlet  306  extending through the lid  322 . The resulting fluidized powder mixture exits the interior space  304  via an outlet  308  extending through the lid  322  to be delivered to the target site. The device  300  also includes a tube  310  extending from a first end  328  connected to the outlet  308  to a second end  314  extending into the interior space  304 . Rather than a single slot extending through a wall of the tube  310 , however, the tube  310  includes a plurality of slots  312  distributed about the tube  310  to prevent uneven distribution of powder within the canister  302  and prevent powder build up on any side of the tube  310 , which may decrease fluidized powder mixture delivery rates. 
     In one embodiment, as shown in  FIG.  20   , the tube  310  includes four slots  312 , distributed about the tube  310  and spaced equidistantly from one another. The slots  312  in this embodiment are positioned proximate the first end  328 . It will be understood by those of skill in the art, however, that the number, position and configuration of the slots  312  may be varied. 
     As shown in  FIG.  21   , a device  400  according to another embodiment of the present disclosure is substantially similar to the devices  100 ′,  200 , and  300  described above, unless otherwise indicated. The device  400  comprises a canister  402  defining an interior space  404  within which a powdered agent  405  is received and fluidized to form a fluidized powder mixture for delivery to a target site of within a living body. Similarly, the device  400  may include a lid  422  enclosing the interior space  404  along with an inlet  406  via which gas is supplied to the interior space  404  to fluidize the powdered agent  405  and an outlet  408  via which the fluidized powder agent exits the canister  402  to be delivered to the target site. The device  400  may also include a tube  410  extending into the interior space  404  in communication with the outlet  408 . The device  400  further comprises a filler chamber  450  coupled to the canister  402 , in communication with the interior space  404  of the canister  402 . The filler chamber  450  houses filler material  452  such as, for example, mock particles, beads, tiny “bounce balls” or a foam material, which is injected into the canister  402  as fluidized powder mixture exits the canister  402  to make up for a loss in volume of the powdered agent as the fluidized powder mixture is delivered to the target site. The filler material  452  is injected into the canister  402  to maintain a constant ratio of volume of material (e.g., powdered agent and filler) to volume of gas within the canister  402  to maintain a desired rate of delivery of the fluidized powder mixture to the target site. 
     The filler chamber  450  may be connected to the canister  402  so that the filler material  452  passes from the filler chamber  450  to the canister  402  via a filler inlet  454 . In one embodiment, the filler chamber  450  may also include a gas inlet  456  so that, when a user actuates the delivery of the fluidized powder mixture to the target site via, for example, pressing a trigger, gas is supplied to both the canister  402  and the filler chamber  450 . The gas supplied to the filler chamber  450  drives the filler material  452  out of the filler chamber  450  into the canister  402 . The filler chamber  450  may include a pressure regulator to regulate the gas inlet pressure, as necessary, to regulate the volume of filler material  452  being supplied to the canister  402  to correspond to the volume of powdered agent  405  exiting the canister  402 . In one embodiment, the filler inlet  454  may be sized, shaped and/or otherwise configured to facilitate passage of a single stream of filler material  452  (e.g., beads) therethrough into the canister  402 . 
     Filler material  452  is configured to be able to enter the interior space  404  of the canister  402 , but is prevented from exiting the canister  402  during delivery of the fluidized powder mixture. In one embodiment, this is achieved via a sizing of the individual particles of the filler material  452 . For example, the filler material  452  may be sized and/or shaped to prevent it from entering the tube  410  and/or the outlet  408 . In other words, each bead or particle of the filler material  452  is selected to be larger than an opening of the tube  410  and/or an opening of the outlet  408 . The filler material  452  is sized and shaped to be large enough to prevent the filler material from exiting the canister  402 , while also being configured to bounce off walls  403  of the canister  402  as the powdered agent is moved within the interior space  404  and is fluidized to prevent clogging of the device  400 . 
     Thus, in use, the canister  402  of the device  400  loses powder during delivery of the fluidized powder agent, but will compensate for the loss by simultaneously supplying the canister  402  with a corresponding volume of filler material  452 . The rate of delivery of filler material  452  into the canister  402  may be determined by calculating a powder volume that has been lost given a fluidized powder mixture delivery rate, and adjusting it based on volume and flow rate differences of the filler material  452  versus the powdered agent  405 . The rate of delivery of filler material  452  into the canister  402  is selected to compensate for the loss in volume of the powder  405  to maintain a substantially constant fluidized powder mixture delivery rate. Although the inlet  406  of the canister  402  and the gas inlet  456  of the filler chamber  450  are shown and described as coupled to a single gas source, it will be understood by those of skill in the art that each of the inlet  406  and the gas inlet  456  may be coupled to separate gas sources, each of which supply gas to the inlet  406  and the gas inlet  456  when delivery of fluidized powder mixture to the target site is actuated and/or triggered. 
     As shown in  FIGS.  22  and  23   , a device  500  may be substantially similar to the device  400 , unless otherwise indicated. The device  500  comprises a canister  502  defining a first interior space  504  within which powdered agent is received and fluidized to deliver a fluidized powder mixture to a target site of a patient for treatment. Rather than a separate filler chamber, however, the canister  502  defines both the first interior space  504  and a second interior space  550  which, when the device  500  is in an operative position, extends above the first interior space  504 . In addition, rather than filling the first interior space  504  with a filler material to maintain a constant volume of material (powder and/or filler) therein, the second interior space  550  houses additional powdered agent, which may be supplied to the first interior space  504  via gravity as the fluidized powder mixture exits the first interior space  504  to be delivered to the target site. An inlet and outlet (not shown) are in communication with the first interior space  504  so that only the powdered agent contained within the first interior space  504  is fluidized to form the fluidized powder mixture and only the powdered agent within the first interior space  504  is permitted to exit the device  500  to the target site. 
     The second interior space  550  may be in communication with the first interior space  504  via an opening  554  extending therebetween. The device  500  further comprises a door  558  movable between a first configuration prior to commencement of a treatment procedure, as shown in  FIG.  22   , and a second configuration during a course of treatment, as shown in  FIG.  23   . In the first configuration, the door  558  may extend over the entire opening  554  when fluidized powder mixture is not being delivered, to prevent the passage of any powdered agent from the second interior space  550  to the first interior space  504 . As shown via the dotted line in  FIG.  22   , the first interior space  504  contains a given volume of powdered agent therein. 
     When the user actuates and/or triggers delivery of the fluidized powder mixture, as shown in  FIG.  23   , movement of the door  558  may also be triggered so that the door  558  opens to expose the opening  554 , permitting the passage of powdered agent from the second interior space  550  to the first interior space  504 . Actuation of the door  558  may be triggered in any of a number of different ways. For example, the door  558  may include a motor that is activation, upon actuation of the device  500 , a magnetic mechanism that uses magnetism to open the door  558  upon activation and/or pressure differentials created by the pressure increase upon device actuation. The second interior space  550  may include an angled surface  560  which directs the powdered agent toward the opening  554  so that, when the door  558  is open, the powdered agent within the second interior space  550  is permitted to fall into the first interior space  504 . Thus, the first interior space  504  is passively fed with the additional powdered agent via gravity. As shown via the dotted line in  FIG.  23   , the volume of powder within the first interior space  504  should remain constant during the course of treatment since the first interior space  504  is being fed via the second interior space  550  as the fluidized powder mixture is being delivered. The opening  554  may be sized and/or otherwise configured to allow powdered agent to fall therethrough at a controlled rate selected to keep the volume of powdered agent within the first interior space  504  substantially constant. 
     Although the additional powdered agent within the second interior space  550  is described as being passively fed into the first interior space  504  via gravity, in an alternate embodiment, as shown in  FIGS.  24  and  25   , powdered agent within a second interior space  550 ′ of a canister  502 ′ of a device  500 ′ may be actively fed into a first interior space  504 ′ of the canister  502 ′ via, for example, a turbine  562 ′ which may be powered via a gas flow. In this embodiment, a rotatable paddle  564 ′ is mounted within an opening  554 ′ extending between the first and second interior spaces  504 ′,  550 ′. The rotatable paddle  564 ′ is connected to the turbine  562 ′, which is positioned along an exterior of the canister  502 ′ and housed within a gas flow path  566 ′. The gas flow path  566 ′ may be configured as a connecting element  524 ′ connecting a gas source to an inlet (not shown), which permits passage of gas therethrough into the first interior space  504 . Thus, the connecting element  524 ′, in this embodiment, extends along an exterior side of the canister  502 ′ to accommodate the turbine  562 ′. 
     In a first configuration of device  500 ′, as shown in  FIG.  24   , in which delivery of fluidized powder mixture is not actuated and thus no gas flows through the flow path  566 ′, the turbine  562 ′ does not rotate and thus no powdered agent is permitted to pass from the second interior space  550 ′ to the first interior space  504 ′. As shown in  FIG.  25   , when delivery of the fluidized powder mixture is actuated, in a second configuration, the turbine  562 ′ is rotated via a flow of gas passing through the gas flow path  566 ′. Rotation of the turbine  562 ′ correspondingly rotates the paddle  564 ′ to actively drive the powdered agent within the second interior space  550 ′ through the opening  554 ′ and into the first interior space  504 ′. Since the flow of gas is initiated when a user actuates and/or otherwise triggers delivery of a fluidized powder mixture to a target site, a supply of powdered agent from the second interior space  550 ′ to the first interior space  504 ′ will occur simultaneously with the exiting of powdered agent (e.g., the fluidized powder mixture) from the first interior space  504 ′ to maintain a substantially constant volume of powdered agent within the first interior space  504 ′. Maintaining the volume of powdered agent within the first interior space  504 ′ will correspondingly maintain a substantially constant delivery rate of the fluidized powder mixture. 
     Although the above embodiment describes a single gas source/supply, it will be understood by those of skill in the art that the turbine  562 ′ may be driven via a gas source separate from a gas source connected to an inlet of the device  500 ′ so long as a volume of powdered agent supplied from the second interior space  550 ′ to the first interior space  504 ′ corresponds to a volume of powdered agent exiting the first interior space  504 ′. In addition, although the embodiment describes active transfer of the powdered agent via a gas powered turbine, active transfer from the second interior space  550 ′ to the first interior space  504 ′ may also occur via other mechanisms. 
     As shown in  FIG.  26   , a device  1200  for fluidizing and delivering a powdered agent (e.g., hemostatic agent) according to an embodiment of the present disclosure comprises a canister  1202  and a piston  1204  movably coupled to the canister  1202 . The canister  1202  is configured to receive the powdered agent within an interior space  106  thereof. The canister  1202  is subsequently filled with a gas via an inlet  1208  that may be connected to a gas source via, for example, a tubular member  1212 . The powder is fluidized via the gas to form a two-phase mixture that may be sprayed onto the target site (e.g., bleeding site) via a catheter  1214  connected to an outlet  1210 . The catheter  1214  is sized and shaped and sufficiently flexible to be endoscopically inserted into a patient body to the target site (e.g., along a tortuous path traversed by a flexible endoscope through a body lumen accessed via a natural body orifice). In order to maintain a substantially constant delivery rate of the mixture to the target site, the piston  1204  is movable relative to the canister  1202  to decrease a volume of the interior space  1206 , during the course of treatment of the target site. Thus, as a volume of powder within the canister  1202  is decreased, the volume of the interior space  1206  is also decreased to maintain a substantially constant powder volume to canister volume ratio. The piston  1204  may be moved relative to the canister  1202  in any of a number of different ways. In this embodiment, the piston  1204  is moved via a pneumatic cylinder or motor  1216 . 
     The canister  1202  of this embodiment is formed of a rigid material to define the interior space  1206 , which is configured to receive the powdered agent along with the gas to form the gaseous fluid mixture that is sprayed on the target site to provide treatment thereto. The canister  1202  extends longitudinally from an open first end  1216  to a closed second end  1218 . The piston  1204  is movably coupled to the canister  1202  at the first end  1216  and is movable toward the second end  1218  to reduce the volume of the interior space  1206 . The piston  1204  encloses the interior space  1206  so that the powder, gas and/or the gas mixture do not leak from the canister  1202 , and exit the canister  1202  via the outlet  1210  and from there into the catheter  1214  to exit toward the target site. Thus, the piston  1204  of this embodiment is received within the open first end  1216  and is substantially sized and shaped to correspond to a size and shape of an opening at the first end  1216 . In one example, the canister  1202  is substantially cylindrical while the piston  1204  is substantially disc-shaped to be received within the open first end  1216  of the canister  1202 . The canister  1202  is sized and shaped so that the piston  1204  is movable along at least a portion of a length thereof toward the second end  1218  to reduce a volume of the interior space  1206  while also preventing leakage of any fluids/substances received within the interior space  1206 . In one example, the piston  1204  includes a sealing ring extending about a circumference thereof to prevent leakage of any powder, gas and/or fluid therepast. 
     As described above, the device  1200  also includes the inlet  1208  via which gas is introduced into the interior space  1206  and the outlet  1210  via which the fluidized powder is delivered to the catheter  1214  to reach the target site. In one embodiment, each of the inlet  1208  and the outlet  1210  are configured as an opening extending through a portion of the piston  1204  to be connected to the tubular member  1212  and the catheter  1214 , respectively. It will be understood by those of skill in the art, however, that the inlet  1208  and the outlet  1210  may be positioned on or along any portion of the canister  1202  and/or the piston  1204  so long as the inlet  1208  is configured to receive a high pressure gas therethrough and into the interior space  1206 , and the outlet  1210  is connectable to a delivery element such as, for example, the catheter  1214 , which delivers the fluidized mixture from the interior space  1206  to the target site. It will also be understood by those of skill in the art, that although the inlet  1208  is described as connected to the gas source via the tubular member  1212 , the inlet  1208  may be connected to the gas source via any of a number of couplings so long as sufficient gas flow is deliverable therethrough. In addition, although the outlet  1210  is shown and described as an opening extending through the piston  1204 , it will be understood by those of skill in the art that the outlet  1210  may also be configured to include a hypotube extending into the interior space  1206  so that fluidized mixture formed within the interior space  1206  may be received within the hypotube to be delivered to the target site via the catheter  1214 . 
     In this embodiment, the piston  1204  is movable relative to the canister  1202  via a pneumatic cylinder or motor  1220 . The device  1200  may be programmed to include one or more inputs such as, for example, time. When it is desired to deliver the fluidized mixture to the target site, the user may initiate delivery using a controller such as a trigger. For example, when the user depresses the trigger to deliver the fluidized mixture, the piston  1204  moves toward the second end  1218  at a preset rate. When the user releases the trigger, the piston  1204  may stop, maintaining its position relative to the canister  1202  until the user depresses the trigger again. Alternatively or in addition, the device  1200  may use other inputs such as, for example, inputs based on flow and/or pressure sensors within the interior space  1206  of the canister  1202 , the inlet  1208  and/or the outlet  1210 . 
     Although the piston  1204  of the device  1200  is described and shown as driven via the pneumatic cylinder or motor  1220 , it will be understood by those of skill in the art that the piston  1204  may be moved from its initial position proximate the first end  1216  toward the second end  1218  via any of a variety of different drive mechanisms, examples of which will be described in further detail below. In addition, although the piston  1204  is shown as forming a base (e.g., bottom portion) of the canister  1202 , it will be understood by those of skill in the art that the piston  1204  may be coupled to the canister  1202  in any of a number of configurations. In particular, the piston  1204  may also be configured as a lid (e.g., top portion) of the canister  1202 . In a further embodiment, the device  1200  may include more than one piston  1204 , each of which are movable relative to the canister  1202  to reduce the volume of the interior space  1206  thereof. 
     According to example method using the device  1200 , the canister  1202  may be filled with the powdered agent such as, for example, a hemostatic agent, prior to assembly of the device  1200 . Upon filling the canister  1202  with a desired amount of powder, the canister  1202  and the piston  1204  are assembled, the inlet  1208  is coupled to the gas source via, for example, the tubular member  1212 , and the outlet  1210  is coupled to the catheter  1214 . The catheter  1214  may then be inserted to the target site within the body through a working channel of a delivery device such as an endoscope. The user may depress a trigger or other controller to introduce a high flow gas into the interior space  1206  of the canister  1202  to form the fluidized mixture and deliver the fluidized mixture to the target site (e.g., a bleeding site) to provide treatment thereto. When the trigger is depressed, the pneumatic cylinder or motor  1220  is operated to move the piston  1204  toward the second end  1218  reducing the volume of the interior space  1206  by an amount corresponding to the reduction in the volume of powder remaining within the interior space  1206  as reduced the powder exits the canister  1202  via the outlet  1210 . When the user releases the trigger, both the delivery of the fluidized mixture and the movement of the piston  1204  are halted. Thus, the piston  1204  moves only while the fluidized mixture is being delivered so the reduction in the volume of the interior space  1206  corresponds to the reduction in the volume of powder remaining housed within the interior space  1206 . As described above, a rate of movement of the piston  1204  may be based on inputs such as, for example, time, flow and/or pressure within the canister  1202 , inlet  1208  and outlet  1210 . In one embodiment, the piston  1204  is configured to move at a rate which maintains a substantially constant ratio of the volume of the interior space  1206  available in the canister  1202  to the volume of remaining powder to maintain a substantially constant fluidized mixture delivery rate. 
     As shown in  FIG.  27   , a device  1300  according to another embodiment is substantially similar to the device  1200 , comprising a canister  1302  and a piston  1304  movably coupled thereto to move from an initial position proximate a first end  1316  of the canister  1302  toward a second end  1318  to reduce a volume of an interior space  1306  of the canister  1302  as a fluidized powder mixture is delivered to a target site. Similarly to the device  1200 , high flow gas is delivered to the interior space  1306  to fluidize a powdered agent received within the canister  1302  to form a fluidized mixture for delivery to a target site in the body. Gas is received within the canister  1302  via an inlet  1308  connected to a gas source via, for example, a tubular member  1312 . The fluidized mixture is delivered to the target site via a delivery catheter  1314  connected to an outlet  1310  of the device  1300 . In this embodiment, however, the piston  1304  is moved via a chamber  1320  including an expandable member  1322 , which expands as gas is received therein. In particular, when a user triggers a controller (e.g., depresses a trigger) to deliver the fluidized mixture to the target site, a portion of the gas is diverted into the expandable member  1322  so that the gas expands the expandable member  1322 , as shown in broken lines in  FIG.  27   , thereby moving the piston  1304  toward the second end  1318 . 
     The chamber  1320 , which houses the expandable member  1322 , in this embodiment is connected to the first end  1316  of the canister  1302  on a side of the piston  1304  opposite the interior space  1306  so that, as the expandable member  1322  expands, the piston  1304  is moved toward the second end  1318  of the canister  1302 . The expandable member  1322  is also connected to the gas source via a connecting member  1324 , which includes a one way valve so that gas may pass therethrough in a first direction into the expandable chamber  1322 , but is prevented from flowing in a second direction out of the expandable chamber  1322 . As described above, gas is directed into the chamber  1320  only while the fluidized mixture is being delivered to the target site so that a reduction of the volume of the interior space  1306  corresponds to a reduction in volume of the powdered agent within the canister  1302 . Similarly to the device  1200 , the device  1300  may receive inputs corresponding to flow, pressure and/or time, that may control a rate at which the piston  1304  is moved toward the second end  1318 . It will be understood by those of skill in the art that the device  1300  may be used in a manner substantially similar to the device  1200 . 
     As shown in  FIGS.  28  and  29   , a device  1400  according to another embodiment may be substantially similar to the devices  1200 ,  1300  described above, comprising a canister  1402  for receiving a powdered agent within an interior space  1406  thereof and a piston  1404  movably coupled to the canister  1402 . High flow gas is delivered to the interior space  1406  via an inlet  1408  that is connected to a gas source to form a fluidized powder mixture for delivery to a target treatment area via a delivery catheter  1414  connected to an outlet  1410  of the device  1400 . The piston  1404  is movable from an initial position proximate a first end  1416  of the canister  1402  toward a second end  1418  to reduce a volume of the interior space  1406  as a volume of the powdered agent within the interior space  1406  is reduced. The device  1400 , however, further includes a turbine  1426  connected to a threaded rod  1428  to which the piston  1404  is threadedly coupled. The turbine  1426  is housed within a bypass  1424  connected to the first end  1416  if the canister  1402 . A portion of the gas is diverted through the bypass  1424  when the user triggers a controller to deliver the fluidized mixture. The flow of gas through the bypass  1424  spins the turbine  1426 , thereby causing the threaded rod  1428  to rotate about a longitudinal axis thereof. As the threaded rod  1428  is rotated, the piston  1424  is moved longitudinally therealong toward the second end  1418 . 
     As shown in  FIG.  29   , the bypass  1424  including a first opening  1430  through which gas is received and second opening  1432  through which gas exits so that gas flows through the bypass  1424  from the first opening  1430  to the second opening  1432  to rotate the turbine  1426  housed therein. The threaded rod  1428  is connected to the turbine  1426  so that rotation of the turbine  1426  results in rotation of the threaded rod  1428 . Since the piston  1404  is threaded over the rod  1428 , rotation of the threaded rod  1428  causes the piston  1404  to be moved longitudinally therealong. The piston  1404  is threaded over rod  1428  so that rotation of the threaded rod  1428  via the flow of gas through the bypass  1424  results in the longitudinal movement of the piston  1404  toward the second end  1418 . Similarly to the device  1300 , a portion of the gas is only diverted through the bypass  1424  during delivery of the fluidized mixture so that a reduction in volume of the interior space corresponds to a volume of powder remaining in the interior space  1406 . It will be understood by those of skill in the art that the device  1400  may be used in a manner substantially similar to the devices  1200 ,  1300 , as described above. 
     As shown in  FIG.  30   , a device  1600  according to another embodiment of the present disclosure may be substantially similar to the devices  1200 ,  1300 , and  1400 , described above, comprising a canister  1602  configured to receive a powdered agent therein for fluidization via a gas. Similar to the devices  1200 ,  1300 , and  1400 , a volume of an interior space  1606  of the canister  1602  is reduced as a fluidized mixture is delivered to a target site for treatment. Rather than reducing the volume of the interior space  1606  via a movable piston, however, the device  1600  includes an expandable member  1604  which expands into the interior space  1606 , as shown in broken lines in  FIG.  30   , of the canister  1602  to reduce the volume thereof. 
     Similarly to the devices  1200 ,  1300 , and  1400 , gas is supplied into the canister  1602  via an inlet  1608 , which may be connected to a gas source via a connecting member  1612 . The fluidized mixture is delivered to the target site via a delivery catheter  1614  connected to an outlet  1610 . The device  1600  further comprises a secondary chamber  1620  connected to the canister  1602 . Similarly to the device  1300  described above, a portion of the gas from the gas source may be diverted into the secondary chamber during delivery of the fluidized mixture. An interior space  1634  of the secondary chamber  1620  is separated from the interior space  1606  of the canister  1602  via the expandable member  1604 . In this embodiment, the expandable member  1604  is configured as an expandable diaphragm extending between the canister  1602  and the secondary chamber  1620  so that, when gas is received within the interior space  1634  of the secondary chamber  1620 , a pressure differential between the interior space  1634  of the secondary chamber  1620  and the interior space  1606  of the canister  1602  causes the expandable member to deflect into the canister  1602 , as shown in broken lines in  FIG.  30    reducing the volume of the interior space  1606 . 
     As described above with respect to the devices  1300 ,  1400 , gas is only diverted into the secondary chamber  1620  during the delivery of the fluidized mixture. When delivery is triggered gas is diverted to the secondary chamber  1620 . When the user releases the trigger for delivery, delivery of gas to the secondary chamber  1620  is halted. As also discussed above, the amount of flow diverted to the secondary chamber  1620  may be dictated by time, pressure and/or flow detected within the device  1600 . As more gas flows into the secondary chamber  1620 , its pressure increases to force the diaphragm to deflect further into the interior space  1606  of the canister  1602 . Thus, the device  1600  may be utilized in a manner substantially similar to the devices described above. 
     Although the device  1600  shows and is described with respect to a single expandable diaphragm, it will be understood by those of skill in the art that the device  1600  may include more than one expandable diaphragm and the expandable member may have any of a variety of shapes and configurations. 
     As shown in  FIG.  31   , a device  1700  according to another embodiment may be substantially similar to the device  1600 , described above, comprising a canister  1702  including an expandable member  1704  which expands to reduce a volume of a first interior space  1706  of the canister  1702  as a powdered agent received therewithin is fluidized and delivered to a target site for treatment. In this embodiment, however, the expandable member  1704  may be housed within the canister  1702  to define both the first interior space  1706  in which the powdered agent is fluidized and a second interior space  1708  into which a portion of a gas may be diverted to cause the expandable member  1704  to deflect into the first interior space  1706  to reduce a volume thereof. A first end  1716  of the canister  1702  may be substantially closed via a base portion  1740 . An inlet  1708  for supplying gas into the first interior space  1706  and an outlet  1710  via which the fluidized mixture is delivered to the target site may extend through the base portion  1740  in communication with the first interior space  1706 . 
     The expandable member  1704  may, in one example, have a substantially cylindrical configuration. The cylindrically shaped expandable member  1704  is housed within the canister  1702  so that an interior of the expandable member  1704  defines the first interior space  1706  within which the powdered agent is housed and subsequently fluidized via a high flow gas supplied from a gas source thereto via the inlet  1708 . The second interior space  1720  is defined via an exterior surface  1736  of the expandable member  1704  and an interior surface  1738  of the canister  1702  so as the fluidized mixture is delivered to the target site from the first interior space  1706  via a delivery catheter  1714  connected to the outlet  1710 , a portion of gas from the gas source gas is diverted into the second interior space  1738  via a connecting element  1724 . A pressure differential between the first and second interior spaces  1706 ,  1720  causes the expandable member  1704  to deflect into the first interior space  1706 , as shown in broken lines in  FIG.  31   , toward an expanded configuration, as shown via the broken lines in  FIG.  31   , reducing the volume of the first interior space  1706  as a volume of the powder in the first interior space  1706  is reduced. In one embodiment, in the expanded configuration, the expandable member  1704  may form a substantially hourglass shape. It will be understood by those of skill in the art, however, that the expandable member  1704  may have any of a variety of shapes and configurations so long as the expandable member  1704 , when expanded, reduces a volume of the first interior space  1706 . Similarly to the devices described above, gas is only diverted into the second interior space  1720  during delivery of the fluidized mixture and may be controlled via inputs including time, and/or flow and/or pressure within the device  1700 . 
     Although the device  1700  is shown and described as including a substantially cylindrically shaped expandable member  1704 , it will be understood by those of skill in the art that the expandable member  1704  may have any of a variety of shapes so long as the expandable member defines first and second interior spaces  1706 ,  1720 , as described above. 
     As shown in  FIG.  32   , a device  1800  according to another embodiment may be substantially similar to the device  1700  described above, comprising a canister  1802  and an expandable member  1804  defining a first interior space  1806 , in which a powdered agent is fluidized via gas from a gas source to form a fluidized mixture, and a second interior space  1820 , which receives a portion of gas diverted from the gas source during delivery of the fluidized mixture to a target treatment area. The first interior space  606  is defined via an interior wall  1805  of the expandable member  1804 . The second exterior space  1820  is defined via an exterior wall  1836  of the expandable member  1806  and the interior surface  1838  of the canister  1802 . In this embodiment, however, the expandable member  1804  extends from a first end  1816  of the canister  1802  to a second end  1818  of the canister  1802  so that, in an initial biased configuration, the expandable member  1804  may substantially correspond in shape to the canister  1802 . As the second interior space  1820  is filled with diverted gas, however, the expandable member  1804  deflects into the first interior space  1806 , as shown in broken lines in  FIG.  32   , increasing a volume of the second interior space  1820  and thereby reducing a volume of the second interior space  1820 . 
     Similarly to the device  1700 , the device  1800  also includes a base portion  1840  at a first end  1816  of the canister  1802  for enclosing the first and second interior spaces  1806 ,  1820 . An inlet  1808  and an outlet  1810  extend through the base portion  1840  in communication with the first interior space  1806  so that gas may be supplied thereto via the inlet  1808  to fluidize the powdered agent therein and so that the fluidized mixture may be delivered to the target site via the outlet  1810 . A portion of the gas from the gas source may be diverted into the second interior space  1820  via a connecting element  1824 , which may be positioned along the base portion  1840  in communication with the second interior space  1820 . 
     As described above, during delivery of the fluidized mixture to the target site, a portion of the gas is diverted into the second interior space  1820  so that a pressure differential between the first and second interior spaces  1806 ,  1820  causes the expandable member to be diverted radially inward, as shown in broken-lines in  FIG.  32   , to reduce the volume of the first interior space  1806 . Thus, as the volume of the powdered agent within the first interior space  1806  is reduced, the volume of the first interior space  1806  is correspondingly reduced to maintain a substantially constant delivery rate of the fluidized mixture. In a diverted configuration, the expandable member  1804  may take on a substantially conical shape. It will be understood by those of skill in the art, however, that the expandable member  1804  may have any of a configurations, shapes and sizes so long as the expandable member  1804  is formed of a flexible, deflectable material which defines both a first interior space  1806  within walls thereof, and a second interior space  1820  between the expandable member  1804  and walls of the canister  1802 . 
     As shown in  FIG.  33   , a device  1900  according to another embodiment may be substantially similar to the devices  1600 ,  1700 , and  1800  described above, comprising a canister  1902  and an expandable member  1904 , which expands to reduce a volume of an interior space  1906  of the canister  1902  as a powdered agent is fluidized and delivered to a target site of treatment. The volume of the interior space  1906  is reduced to correspond to a reduction in a volume of the powdered agent within the interior space  1906 . The expandable member  1904  in this embodiment, however, is configured as an expandable balloon housed within the interior space  1906 . Thus, as a volume of the balloon  1904  is increased as it is inflated, the volume of the interior space  1906  is decreased. 
     Similarly to the devices  1600 ,  1700 , and  1800 , the device  1900  includes an inlet  1908  for supplying a gas to the interior space  1906  to fluidize the powdered agent and an outlet  1910  via the fluidized mixture is delivered to the target site. The inlet and outlet  1908 ,  1910  may be extend through a base portion  1940  of the device  1900  which is coupled to an end of the canister  1902  to define the interior space  1906 . A portion of the gas supplied to the device  1900  may be diverted to the expandable member  1904  via a connecting element  1924  to cause the balloon to become inflated, filling the interior space  1906 . As described above, the inlet  1908  may have any of a variety of configurations and, in one embodiment, may include a hypotube  1911  extending into the interior space  1906 . The hypotube  1911  may include a slot  1944  extending through a wall thereof along a portion thereof. The inflated expandable member  1904  may fill the space, surrounding the hypotube  1911  without restricting gas and powder flow through the slot  1944 . Although the hypotube  1911  is described as including the slot  1944 , it will be understood by those of skill in the art that the term “slot” may refer to any opening or hole extending through a wall thereof. 
     The connecting element  1924  may be coupled to the base portion  1940 , as shown, to deliver gas to the expandable member  1904 . It will be understood by those of skill in the embodiment, that the connecting element  1920  may extend through the interior space  1906  to connect to the expandable member  1904 . Alternatively, as shown in  FIG.  34   , a device  1900 ′ may have a separate feed line  1924 ′ which extends through a portion of a canister  1902 ′ to supply gas to an expandable member  1904 ′ housed therein. It will be understood by those of skill in the art that an expandable member  1904 ,  1904 ′ having a balloon configuration may be supplied with gas for inflating the expandable member via any of a variety of mechanisms. 
     Catheter  190  is shown in  FIG.  35    in a coiled, rolled-up configuration. Catheter  190  includes a proximal end  191 , a distal end  193 , and an intermediate portion  192  connecting proximal end  191  and distal end  193 . Proximal end  191  may be connected to outlet  34  by any mechanism, such as a screw or snap fit mechanism. Alternatively, proximal end  191  may be a complementary luer, e.g. a male or a female luer, to a luer provided at outlet  34 . As shown in  FIG.  35   , proximal end  191  may include a butterfly-shaped device to assist in screwing or otherwise attaching catheter  190  to application device  30 . When a propellant fluid and material mixture is dispensed from application device  30 , the mixture may travel through catheter  190  (preferably in an unrolled configuration) and may be dispensed from distal end  193  at the target site. Catheter  190  may be any size appropriate for introducing the device into a patient while maintaining column strength such that catheter  190  does not buckle when passed though an endoscope. For example, catheter  190  may be approximately 200-275 cm, and preferably approximately 210-250 cm. Further, a diameter of catheter  190  may be approximately seven (7) to eight (8) French, and a wall thickness of catheter  190  may be approximately 0.05-0.15 inches, or preferably approximately 0.1 inches. In addition, catheter  190  may be nylon or any other suitable material. However, the size and the material of the catheter is not limited thereto. 
     Although many features are described as cylindrical, the shape of the elements are not limited thereto. Rather, the features may be any shape suitable for regulator  40  to properly regulate a fluid dispersion from containment device  20 ,  20 ′. Moreover, unless described otherwise, the structural elements of application device  30  and/or regulator  40 ,  40 ′ may be any material known in the art, including but not limited to a metal alloy, a ceramic, and/or a resin. Further, although the above embodiments are described as diverting a portion of gas from a gas source/supply to drive movement of a piston or expansion of an expandable member, it will be understood by those of skill in the art that the devices described above may include one or more gas source(s) for providing gas to both the interior space and for driving the piston and/or causing expansion of the expandable member. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed device without departing from the scope of the disclosure. For example, any material or fluid may be contained in the chamber and may mix with the propellant fluid to be expelled from the application device to a target location. Additionally, or alternatively, unless otherwise specified, the medical device described herein may be formed of any metal, plastic, or ceramic, or any combination thereof, suitable for use in medical applications. Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.