Patent Publication Number: US-2021162189-A1

Title: Medical delivery device and method of use

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority from U.S. Provisional Application No. 62/942,919, filed on Dec. 3, 2019, which is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to endoscopic medical devices and related methods of use. More particularly, in some embodiments, the disclosure relates to endoscopic medical tools and methods related to accessing target sites and dispensing materials to the target sites. 
     BACKGROUND 
     In certain medical procedures, it may be necessary to stop or minimize bleeding internal to the body. For example, an endoscopic medical procedure may require hemostasis of bleeding tissue within the gastrointestinal tract, for example in the esophagus, stomach, or intestines. 
     During an endoscopic procedure, a user inserts a sheath of an endoscope into a body lumen of a patient. The user utilizes a handle of the endoscope to control the endoscope during the procedure. Tools are passed through a working channel of the endoscope via, for example, a port in the handle, to deliver treatment at the procedure site near a distal end of the endoscope. The procedure site is remote from the operator. 
     To achieve hemostasis at the remote site, a hemostatic agent may be delivered by a device inserted into the working channel of the endoscope. Agent delivery may be achieved through mechanical systems, for example. Such systems, however, may not achieve a desired rate of agent delivery or a desired dosage of agent, may result in inconsistent dosing of agent, or may not result in the agent reaching the treatment site deep within the GI tract. The current disclosure may solve one or more of these issues or other issues in the art. 
     SUMMARY OF THE DISCLOSURE 
     According to an embodiment, a medical system includes a handle, a sheath extending from the handle, and an end effector connected to a distal end of the sheath, wherein the end effector is configured to direct a mass of material towards a target site of a body and cause release of the material onto the target site. 
     The medical system may include a catheter including a catheter lumen, wherein the sheath may be configured to extend through the catheter lumen, and wherein the catheter may further include a fluid lumen, fluidly decoupled from the catheter lumen, wherein the fluid lumen may be configured to be attached to a fluid source and may dispense a fluid from a fluid opening at a distal end of the catheter. 
     The medical system may further include a capsule containing the mass of material, wherein the end effector may be configured to advance the capsule along the catheter lumen and to the target site via a lumen opening at a distal end of the catheter. 
     The end effector may include a pair of jaws, and wherein the capsule may include a tether configured to be grasped by the pair of jaws. 
     The end effector may be configured to pull on the tether to open the capsule. 
     An outer covering of the capsule may include a material configured to adhere to the target site when exposed to fluid. 
     An outer covering of the capsule may include a material that dissolves when contacted with fluid. 
     The end effector may be configured to move from a collapsed configuration to an expanded configuration, wherein the end effector may have an umbrella-like shape in the expanded configuration such that a diameter of a distal end of the end effector may be greater than a diameter of a proximal end of the end effector. 
     The catheter may include the capsule within the catheter lumen. 
     The end effector may include a shape memory material, wherein a temperature of the end effector may be configured to be increased by a heat from the body, and wherein the end effector may expand from the collapsed configuration to the expanded configuration when the end effector is above a temperature threshold. 
     The catheter may include a capsule containing the mass of material, wherein a diameter of a distal opening of the catheter lumen may be less than a diameter of the capsule. 
     The distal end of the catheter lumen may include a protrusion extending from a wall of the catheter lumen toward a central longitudinal axis of the catheter configured to rupture the capsule. 
     A diameter of the end effector may be less than the diameter of the distal opening of the catheter lumen, and wherein the end effector may be configured to extend out of the catheter lumen and distal of a distalmost end of the catheter. 
     The end effector may have a disc-shaped distal surface for applying pressure to the material at the target site. 
     The material may be a hemostatic agent or a therapeutic agent. 
     According to another embodiment, a medical system includes an actuation handle, a sheath extending from a distal end of the handle, a catheter including a catheter lumen, wherein the sheath is configured to extend through the catheter lumen, a capsule containing a material wherein the capsule includes a tether, and an end effector connected to a distal end of the sheath and configured to grasp the tether, wherein the end effector is configured to advance the capsule along the catheter lumen and to a target site via a catheter lumen opening at a distal end of the catheter, wherein an outer portion of the capsule includes a material configured to adhere to the target site when exposed to a fluid, and wherein the end effector is configured to cause release of the material from the capsule and onto the target site by applying a force on the tether once the capsule is adhered to the target site. 
     A distal end of the catheter or the sheath may be configured to bend when the distal end of the sheath is distal of a distalmost end of the catheter. 
     According to yet another embodiment, a method of performing a medical procedure includes positioning a catheter adjacent a target site within a body, advancing a sheath distally along a lumen of the catheter, pushing a capsule containing a material along the lumen using an end effector on a distal end of the sheath, expelling the capsule from a distal end of the lumen towards the target site, and releasing the material from the capsule. 
     The method may further include attaching the capsule to the target site, and maneuvering the end effector away from the target site after the capsule is attached to the target site, causing the capsule to rupture. 
     The method may further include actuating the end effector to release the capsule in the body after the capsule is ruptured, and moving the sheath proximally to cause the end effector to reenter the lumen. 
    
    
     
       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 perspective view of a medical tool of the medical system of  FIG. 1 , according to an embodiment; 
         FIGS. 3-5  are perspective views of the medical tool of  FIG. 2 ; 
         FIGS. 6A-6C  are perspective views of a medical tool of the medical system of  FIG. 1 , according to another embodiment; 
         FIGS. 7A and 7B  are perspective views of a medical tool of the medical system of  FIG. 1 , according to another embodiment; 
         FIGS. 8A and 8B  are perspective views of a medical tool of the medical system of  FIG. 1 , according to another embodiment; and 
         FIG. 9  is a perspective view of an actuation device, according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure is now described with reference to an exemplary medical system that may be used to dispense materials endoscopically. However, it should be noted that reference to this 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 device and application method 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, the term “distal” refers to a portion farthest away from a user when introducing the system into a patient. By contrast, the term “proximal” refers to a portion closest to the user when introducing the system into the patient. As used herein, the terms “comprises,” “comprising,” or any other variation 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 necessarily include only those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. The term “exemplary” is used in the sense of “example,” rather than “ideal.” 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  10  according to an embodiment is shown. Medical system  10  includes a flexible shaft  20  (e.g., a catheter) and a handle  40  connected at a proximal end of flexible shaft  20 . Handle  40 , or some other device for actuating or controlling medical system  10  and any tool or devices associated with medical system  10 , includes first and second actuating devices  42 ,  43 , which control articulation of flexible shaft  20 , and/or an articulation joint at a distal end of flexible shaft  20 , in multiple directions. Devices  42 ,  43 , may be, for example, rotatable knobs that rotate about their axes to push/pull actuating elements (not shown). The actuating elements, such as cables or wires suitable for medical procedures (e.g., medical grade plastic or metal), extend distally from a proximal end of endoscope  10  and connect to flexible shaft  20  to control movement thereof. Alternatively, or additionally, a user may operate actuating elements independently of handle  40 . Distal ends of actuating elements extend through flexible shaft  20  and terminate at an actuating joint and/or a distal tip of flexible shaft  20 . For example, one or more actuating elements may be connected to an articulation joint, and actuation of actuating elements may control the actuating joint or the distal end of flexible shaft  20  to move in multiple directions. 
     In addition, one or more electrical cables (not shown) may extend from the proximal end of endoscope  10  to the distal end of flexible shaft  20  and may provide electrical controls to imaging, lighting, and/or other electrical devices at the distal end of flexible shaft  20 , and may carry imaging signals from the distal end of flexible shaft  20  proximally to be processed and/or displayed on a display. Handle  40  may also include ports  44 ,  46  for introducing and/or removing tools, fluids, or other materials from the patient. Port  44  may be used to introduce tools. Port  46  may be connected to an umbilicus for introducing fluid, suction, and/or wiring for electronic components. For example, as shown in  FIG. 1 , port  44  is connected to a lumen  22 , which extends from the proximal end to the distal end of flexible shaft  20 . Port  44  may receive a medical device, such as flexible sheath  120  (e.g., a catheter) of a medical device. 
     As shown in  FIG. 1 , sheath  120  is attached to a distal end of a handle  140 . Handle  140  includes a body  142  defining a hole  142   a  at a proximal end thereof. Sheath  120  is attached at a distal end of body  142 , opposite hole  142   a.  Hole  142   a  may accommodate a thumb (or a finger) of a user. Handle  140  may be integrally formed with or otherwise fixedly attached to sheath  120 . 
     As further illustrated in  FIG. 1 , a slot extends through body  142  in a direction parallel to a longitudinal axis of sheath  120  and body  142 . A portion of a spool  144  (e.g., a slidable member) is disposed in the slot and may move within the slot and along body  142  in a direction parallel to the longitudinal axis. As further shown in  FIG. 1 , spool  144  includes two circular grasping elements  144   a,    144   b,  each having a hole therethrough, extending from spool  144  transverse to the longitudinal axis. Grasping elements  144   a,    144   b  are illustrated as being separated  180  degrees from each other about the longitudinal axis, but the positioning of grasping elements  144   a,    144   b  is not limited thereto. Grasping elements  144   a,    144   b  are grasped by a user to move spool  144  along body  142 . For example, a user may place a thumb in hole  142   a,  an index finger in grasping element  144   a,  and a middle finger in grasping element  144   b,  allowing the user to move spool  144  along the longitudinal axis. Wire  132  is connected to and extends distally from the distal end of spool  144 . Wire  132  extends through a hole (not shown) at the distal end of body  142  and through a lumen (not shown) of sheath  120 . Movement of wire  132  along the longitudinal axis, relative to sheath  120 , actuates end effector  130 , as will be explained herein. Alternatively, wire  132  may be rotatable about a rotation mechanism  143 , such as a screw mechanism or any other mechanism known in the art. 
     Referring to  FIGS. 2-4 , catheter  20  includes a plurality of lumens, e.g., a first lumen  22 , a second lumen  24  (for ease of description, second lumen  24  is shown only in  FIG. 1 ), and a third lumen  26 . According to an example, first lumen  22  is configured to receive sheath  120  of the medical device, as will be described in greater detail herein. First lumen  22  extends from handle  40  and terminates at a first opening  22   a  at a distal end face  28  of catheter  20 . Second and third lumens  24 ,  26  may receive additional tools, and/or may be used for suction/vacuum, dispensing fluid, imaging, illumination, or the like. For example, distal openings  24   a,    26   a  of second and third lumens  24 ,  26  may be open at distal end face  28  of catheter  20 . According to an example, fluid may be expelled through one or both of openings  24   a,    26   a  after traveling along respective second and third lumens  24 ,  26  from handle  40 . Alternatively, debris may be suctioned/vacuumed through one or both of openings  24   a,    26   a,  and/or an electrical fiber may be disposed in on or both of second and third lumens  24 ,  26  and attached to a visualization component, such as a camera, or an illumination member, such as a light emitting diode (LED), disposed at openings  24   a,    26   a.  It will be understood that these components may be fixed in openings  24   a,    26   a,  or the components may be extended from distal end face  28  to provide additional illumination of and/or visualization of a target site T. 
     With continued reference to  FIG. 2 , sheath  120  extends within first lumen  22  of catheter  20 . Sheath  120  is flexible and has an outer diameter less than an inner diameter of first lumen  22 , thereby allowing sheath  120  to slide within and along first lumen  22 . Sheath  120  includes an end effector  130  at a distalmost end. End effector  130  includes a pair of jaws which are actuatable between an open position and a closed position. End effector  130  is configured to grasp a tether  152  of a capsule  150 , as shown in  FIG. 2 , to manipulate capsule  150  and to release contents from capsule  150 , as will be described herein. It will be understood that end effector  130  is not limited to this arrangement, and may be any end effector suitable for performing a medical treatment at a target site. End effector  130  may be any suitable end effector used in a medical procedure, such as scissors, graspers, forceps, needle, etc., or any other therapeutic or diagnostic tool or device, for advancing capsule  150  to target site T and releasing a material  160  from capsule  150 , as will be described herein. In embodiments, capsule  150  does not include a tether  152  and may be grasped about its perimeter. In some embodiments, capsule  150  may be attached to and/or delivered by one or more hemostatic clips, and material  160  may be released in any manner described herein. 
       FIG. 3  illustrates catheter  20  disposed in lumen L of a body and adjacent target site T. Sheath  120  is advanced along first lumen  22  using handle  140  to expose end effector  130  and capsule  150  from distal end face  28  of catheter  20 , by inserting catheter  20  through port  44 . For example, a user may maneuver handle  140  to move sheath  120  distally with respect to catheter  20 . This movement causes end effector  130  to push against a proximal side of capsule  150 , exposing both capsule  150  and end effector  130  from first opening  22   a.  Handle  140  may be further maneuvered to move capsule  150  adjacent target site T. As described herein, openings  24   a,    26   a  may include lighting and/or visualization elements, which may assist in the placement of capsule  140 . 
     As shown in  FIG. 3 , target site T protrudes into lumen L. According to an example, sheath  120  may advance capsule  150  to target site T without needing to further actuate or bend sheath  120 . However, in some examples, target site T may be located on a side of lumen L, as shown in  FIG. 4 , which requires end effector  130  to be maneuvered toward target site T. As discussed above, catheter  20  may include actuating elements, e.g., cables, extending from handle  40 , to the distal end of catheter  20 . Pulling on those cables can bend the end of catheter  20 , as shown in  FIG. 4 . Alternatively, or additionally, sheath  120  may be actuated to be bent or turned to access target site T. For example, sheath  120  may include an actuation section just proximal of end effector  130 , which allows sheath  120  to bend and access target site T. The actuation section may include a shape memory material, e.g., Nitinol, and may be pre-bent to a certain angle such that, when the actuation section is exposed to lumen L, the shape memory material heats up and bends to the preset bend angle. Alternatively, the actuation section may be actuated using cables, wires, or the like, and the bend angle may be selected by the physician during a medical procedure. In this manner, the physician may advance capsule  150  to target site T. 
     As shown in  FIG. 4 , sheath  120  maneuvers capsule  150  to target site T and capsule  150  is adjacent or contacting target site T. In some embodiments, capsule  150  may include an adhesive on an outer surface of capsule  150  and/or a covering of capsule  150  may become adhesive due to exposure to a mucousy or a moist body lumen, or from a fluid expelled via openings  24   a  or  26   a.  According to an example, such a capsule  150  may adhere to target site T with sufficient force to withstand a pulling force on tether  152 , as will be described herein. 
     Once capsule  150  is properly positioned and attached to target site T, sheath  120  may be moved away from target site T to pull on tether  152  and release a material (e.g., a powder)  160 , such as a medical or therapeutic agent, as shown in  FIG. 5 . For example, a physician may maneuver handle  140  such that sheath  120  is moved proximally, thereby moving end effector  130  away from target site T and exerting pressure on tether  152  and causing an outer wall of capsule  150  to break or tear open. Capsule  150  may include perforations or a similar feature that weakens at least a portion of a wall of the capsule, and exerting pressure on tether  152  may rupture the weakened portion of capsule  150 . Capsule  150  may also include two sides of approximately equal size joined together, e.g., via a friction fit, an adhesive, a heat staking, or the like, and exerting pressure on tether  152  may cause the two sides to be pulled apart. Tether  152  may also be attached to a plug fit into a corresponding hole in capsule  150 , such that exerting a force on tether  152  causes the plug to be removed from the hole. According to another example, tether  152  may be woven through overlapping flaps in capsule  150 , and exerting pressure on tether  152  may compromise the seal. Once a seal or a wall of capsule  150  is broken, material  160  may exit capsule  150 . Alternatively, or additionally, the physician may cause a distal actuation section of sheath  120  to otherwise bend and move end effector  130  away from target site T. As end effector  130  moves away from target site T, the adhesion forces acting on capsule  150  cause capsule  150  to remain adhered to target site T, causing tether  152  to break or produce a tear in capsule  150  and release powder  160 . Powder  160  may be a hemostatic agent and may cause a bleed at target site T to coagulate. Alternatively, or additionally, powder  160  may include antibacterial and/or other beneficial medical properties to promote healing and/or other therapeutic benefits at target site T. After deploying powder  160 , end effector  130  may be retracted into lumen  22  along with the remainder of the ruptured capsule  150 . Alternatively, the physician may cause the jaws of end effector  130  to open to release tether  152  and allow capsule  150  to remain in the body to disintegrate and/or to be expelled via natural bodily excretion pathways. It will be understood that the powder-containing element is not limited to capsule  150 . For example, capsule  150  may be any container suitable for containing powder  160  including, but not limited to, a spherical or other-shaped body having an outer protective layer surrounding powder  160 . Alternatively, capsule  150  may not include an outer covering, and may be an agglomeration of powder  160 , such as a mass of powder or other material, held together by an adhesive or other chemical bonds that break apart once exposed to a fluid. It will also be understood that capsule  150  may include compartments to include different types of material that, once exposed to each other, react to form a homogenous material with properties that cause the material to adhere to target site T and/or include therapeutic properties, such as a hemostatic agent. 
     In this manner, target sites that may be difficult to access, such as sites on a roof (top) of a gastrointestinal lumen, may have therapeutic powders applied thereto. It otherwise may be more difficult to apply powdered agents to target sites due to the gravitational forces applied to such powders. It will be understood that while catheter  20  is advanced to target site T and sheath  120  is advanced along first lumen  22  to target site T, catheter  20  is not necessary to deploy capsule  150 . For example, sheath  120 , including end effector  130  attached to capsule  150  via tether  152 , may be advanced along a body lumen to target site T without the use of catheter  20 . 
     A method of applying a therapeutic powder  160  will now be described. 
     Catheter  20  is inserted into a body through a natural orifice or an incision in a patient. Catheter  20  is advanced along a body lumen to target site T. Once catheter  20  is advanced to target site T, sheath  120  is inserted into port  44  and advanced along first lumen  22 . It will be understood that sheath  120  may be inserted into port  44  prior to the beginning of the procedure, e.g., before inserting catheter  20  into the body, and sheath  120  may be advanced to target site T at a same time as catheter  20 . 
     For example, capsule  150  may be inserted into port  44  prior to a distal end of sheath  120 , or end effector  130  may grasp tether  152  prior to inserting capsule  150  and the distal end of sheath  120 . Once both capsule  150  and sheath  120  are inserted into port  44 , sheath  120  is advanced distally toward a distal end of catheter  20 . As sheath  120  is advanced distally, end effector  130  pushes on a proximal end of capsule  150 , causing capsule  150  to advance through lumen  22  of catheter  20 . In an embodiment in which sheath  120  is inserted into a body without catheter  20 , capsule  150  can also be moved to target site T in a similar manner. Alternatively, end effector  130  may pull capsule  150  along a body lumen Las sheath  120  is advanced distally toward target site T. 
     After positioning catheter  20  and sheath  120  adjacent target site T, handle  140  is manipulated to move sheath  120  along first lumen  22  in a distal direction with respect to catheter  20 . Moving sheath  120  in the distal direction forces end effector  130  against the proximal side of capsule  150  and out first opening  22   a  in distal end face  28 . 
     After capsule  150  is positioned outside first lumen  22 , sheath  120  is maneuvered to urge capsule  150  against target site T. According to an example, urging capsule  150  against target site T may include bending a distal end of catheter  20  and/or bending an articulation section of sheath  120 . In some examples, urging capsule  150  against target site T includes dispensing a fluid from openings  24   a  or  26   a  to moisten capsule  150  and activate an adhesive material on an outer surface of capsule  150 . 
     Once capsule  150  is adhered to target site T, sheath  120  is moved away from target site T by moving sheath  120  proximally. Alternatively, end effector  130  may grasp capsule  150  between a pair of jaws. The jaws of end effector  130  may be actuated to increase pressure on capsule  150 , thereby breaking the outer casing of capsule  150  and causing powder  160  to be dispersed at target site T. Sheath  120  is subsequently retracted into lumen  22  and catheter  20  may be removed from the body lumen. According to another example, prior to retracting sheath  120  into lumen  22 , tether  152  may be released by pushing distally on spool  144  and opening the jaws of end effector  130 . In an example where capsule  150  is dissolvable due to interaction with liquid, irrigation may be used to dissolve capsule  150  and release agent  160 . 
     A distal end of medical system  10  according to another example is illustrated in  FIGS. 6A-6C . Like elements are represented by like reference numerals. 
     As shown in  FIG. 6A  and similar to sheath  120  described above, sheath  220  extends through lumen  22  of catheter  20 . Sheath  220  includes an end effector  230  at a distalmost end thereof. As shown in  FIG. 6B , end effector  230  is umbrella shaped in a deployed position, such that a distalmost end of end effector  230  has a diameter greater than a proximalmost end of end effector  230 . End effector  230  may be formed of a shape memory material, such as nitinol. When end effector  230  is exposed to lumen L, heat from the patient&#39;s body may increase the temperature of end effector  230 , thereby causing the shape of end effector to change from a contracted shape to an umbrella shape. Alternatively, end effector  230  may include a collapsible structure that, when disposed within lumen  22 , forms a collapsed or folded orientation, and when exposed from lumen  22 , forms the umbrella shape shown in  FIGS. 6B and 6C . Such a collapsible structure may be formed of a sheet of flexible material. 
     Referring to  FIG. 6A , end effector  230  is collapsed when disposed within lumen  22 . End effector  230  is configured to push a capsule  250 , similar to capsule  140 , out of first opening  22   a  in distal end face  28 . An outer casing of capsule  250  begins to degrade once exposed to moisture, such as the mucosal membrane of lumen L or when sprayed with a fluid from openings  24   a,    26   a.    FIG. 6B  illustrates a release of a powder  260  from capsule  250  after the outer casing of capsule  250  has dissolved. 
     Referring to  FIGS. 6B and 6C , end effector  230  captures or corals powder  260  on an inner, distal surface of the umbrella shaped end effector  230 . According to an example, end effector  230  captures or corals capsule  250  before it is completely dissolved, allowing a greater amount of powder  260  to be captured by end effector  230  and is suspended in body lumen L. Alternatively, end effector  230  can capture powder  260  when powder  260  is not disposed in capsule  230 . 
     As shown in  FIG. 6C , sheath  220  may include an articulation section  222 , similar to the articulation section described above, allowing a medical professional to manipulate end effector  230  to access target site T. End effector  230  may also be manipulated in any manner discussed above with respect to end effector  130 , to bend toward target site T. For example, the medical professional maneuvers end effector  230  toward target site T such that the interior, distal surface of end effector  230  faces target site T, to direct powder  260  onto target site T. End effector  230  is urged against target site  260 , placing pressure on powder  260  at target site T. To maximize the effect of powder  260  on target site T, a position of end effector  230  against target site T may be maintained for a predetermined amount of time. In this manner, the amount of powder  260  dispensed at target site T may be minimized while still maximizing the effectiveness of powder  260 . 
     An operation of sheath  220  will now be described. 
     As discussed above, capsule  250  may be inserted through port  44 , and a distal end of sheath  220  may be subsequently inserted through port  44 , As with sheath  120 , sheath  220  is pushed distally along lumen  22  using handle  140 . End effector  230  pushes against a proximal end of capsule  250  to advance capsule  250  to a distal end of catheter  20 , thereby causing end effector  230  and capsule  250  to exit first opening  22   a.    
     When capsule  250  exits lumen  22 , the medical professional may cause fluid to be emitted from opening  24   a  or opening  26   a  to cause an outer covering of capsule  250  to begin to dissolve or to fully dissolve. Alternatively, as discussed above, capsule  250  may dissolve based on the moisture already present in lumen L. At a same time or subsequently, as end effector  230  exits lumen  22  through opening  22   a,  end effector  230  expands from a collapsed shape to an expanded, umbrella shape, as shown in  FIG. 6B , due to the physical properties of the material forming end effector  230  or via actuation of actuating cables or other actuation mechanism (not shown) to expand end effector  230 . 
     Subsequently, sheath  220  is maneuvered to capture partially dissolved capsule  250  and/or powder  260 . Sheath  220  is then maneuvered so that a distal surface of end effector  230  faces target site T via, e.g., articulation section  222 , and the inner, distal surface of end effector  230  is urged toward target site T, allowing powder  260  to coat target site T. The distal surface of end effector  230  then may be placed in contact with target site T (and powder  260  coating target site T) and pressed against target site T. After a predetermined time period has elapsed, sheath  220  is moved proximally, causing end effector  230  to move into lumen  22  and collapse into the low-profile shape. 
     A distal end of medical system  10  according to another example is illustrated in  FIGS. 7A and 7B . End effector  330  has a same umbrella shape as end effector  230  and may be formed of the same or similar materials and deployed in a same manner as end effector  230 , as described above. 
     As shown in  FIG. 7A , sheath  320  may be maneuvered in any manner described herein with reference to sheaths  120 ,  220  to access target site T, including but not limited to bending catheter  20  and/or bending sheath  330 . Sheath  320  includes a central lumen  324 , which extends from handle  40  to an interior of end effector  330  and terminates at a central opening  324   a.  As shown in  FIG. 7B , end effector  330  extends from first opening  22   a  and faces and surrounds target site T. A capsule (not shown) containing a powder  360 , or powder  360  without a capsule, is transmitted down central lumen  324  to target site T using any dispensing device known in the art. For example, a propellant fluid, such as CO 2  or the like, may force the capsule or powder  360  from a container attached at a proximal end of catheter  20 , e.g., via handle  40 , down central lumen  324 , and out central opening  324   a.  An outer diameter of a distalmost end of end effector  330  defines the area in which the capsule or powder  360  is dispensed to target site T. For example, end effector  330  may be pressed against target site T to create a partial or complete seal between the interior, distal surface of end effector  330  and the wall of lumen L. In this manner, delivery of powder  360  may be targeted directly to target site T, while minimizing the amount of powder released outside of target site T. 
     An operation of sheath  320  will now be described. 
     Sheath  320  is pushed distally along lumen  22  using handle  140 . End effector  330  exits first opening  22   a  and expands in a similar manner as end effector  230 , e.g., based on the physical properties of the material forming end effector  330  or via actuation of actuating cables (not shown) to expand end effector  330 . 
     After end effector  330  is exposed from first opening  22   a,  end effector  330  is maneuvered to cover target site T as shown in  FIG. 7B . For example, an outer periphery of the distalmost end of end effector  330  is placed against a lumen wall LW of lumen L and/or against target site T. In some examples, the outer periphery of the distalmost end of end effector  330  completely surrounds target site T. In other embodiments, target site T may be larger and/or have a shape that is not capable of being completely surrounded by the outer periphery of the distalmost end of end effector  330 . While target site T is shown as being generally parallel to distal end face  28 , target site T may be angled, e.g., approximately perpendicular, to target site T. Accordingly, a distal end of sheath  320  may be articulated in a manner similar to the articulation of articulation section  222  disclosed herein, thereby accessing target site T. 
     Once end effector  330  is positioned against target site T, powder  360 , e.g., a fluidized powder, a capsule, or some other delivery mechanism containing a therapeutic agent, is transmitted along central lumen  324  from a proximal end of sheath  320  to end effector  330 . The powder is expelled from central lumen  324  via central opening  324   a.  Dispersal of powder  360  is limited to target site T surrounded by the outer periphery of end effector  330 . Once powder  360  (transmitted via, e.g., fluidized powder, a capsule, or the like) contacts target T, powder  360  adheres via the moisture of the mucosal and/or a fluid which may be emitted via central lumen  324  and/or openings  24   a,    26   a.  It will be understood that powder  360  may be transmitted along central lumen  324  by any actuation device, e.g., by actuation device  540  shown in  FIG. 9  and discussed in greater detail herein, or any other known delivery mechanism. 
     Another example of a sheath  420  for deploying therapeutic material is shown in  FIGS. 8A and 8B . As shown in  FIG. 8A , sheath  420  includes an end effector  430  having a stamp- or press-like shape. The shape of end effector  430  may be cylindrical or disk-shaped. End effector  430  has a flat or substantially flat distalmost end with a circumference greater than a proximalmost end of end effector  430  and sheath  420 , and the proximalmost end is connected to a distalmost end of sheath  420 . It will be understood that the shape is not limited to a stamp- or press-like shape, and the shape of end effector  430  may include a shape that aids in capturing a capsule or a powder, as described herein. 
     Capsule  450  is positioned distally of end effector  430  in lumen  22 . First opening  22   a  in  FIG. 8A  includes a ring  22   b  to narrow first opening  22   a  (relative to a cross-sectional size or diameter of lumen  22 ). In some embodiments, ring  22   b  includes teeth  24 , or other sharp structures like hooks or barbs, located on a proximal side of ring  22   b  or extending radially inward from an inner perimeter of ring  22   b.  An outer diameter of capsule  450  is greater than a diameter of first opening  22   a.  As sheath  430  is moved distally with respect to catheter  20 , end effector  430  pushes against a proximal side of capsule  450  and capsule  450  is urged against ring  22   b.  The force of urging capsule  450  against ring  22   b,  and in some embodiments teeth  24  or other sharp structure, causes capsule  450  to rupture, releasing powder  460 . Opening  22   a  includes an inner diameter larger than the outer diameter of end effector  430  such that, as sheath  420  continues to be moved distally, end effector  430  is exposed from lumen  22  via opening  22   a.  Powder  460  coats the distalmost surface of end effector  430  and, as with other embodiments described herein, sheath  420  may be maneuvered toward target site T, such as by a bending section  422 . Powder  460  may adhere to target site T either by the moisture of lumen L, or when exposed to a fluid emitted from openings  24   a,    26   a.  A position of end effector  430  against target site T, and pressure applied to target site T by end effector  430 , may be maintained for a predetermined period of time to ensure a suitable amount of powder adheres to treatment site T and is effective, for example, to stop a bleed. It will be understood that ring  22   b  and teeth  24  may be used in any sheath described herein to assist in rupturing a capsule to expose and deliver a material or a powder disposed in the capsule. In addition, in some embodiments, no sharp structure is present on ring  22   b,  and forcing capsule  450  through the smaller diameter opening  22   a  will rupture capsule  450  to disperse powder  460 . 
     An operation of sheath  420  will now be described. 
     As with the other sheaths described herein, capsule  450  is inserted through port  44  prior to inserting a distal end of sheath  420  into port  44 . Sheath  420  is pushed distally along lumen  22  using handle  140 , which causes end effector  430  to push against the proximal end of capsule  450 , causing end effector  430  and capsule  450  to approach first opening  22   a.  As capsule  450  and end effector  430  approach first opening  22   a,  a distal end of capsule  450  contacts a surface of ring  22   b  facing an interior of lumen  22  and/or teeth  24  or other sharp structure arranged on an inner face or inner circumference of ring  22   b.  A force of end effector  430  against the proximal end of capsule  450  and a force of ring  22   b  and/or teeth  24  against the distal end of capsule  450  causes capsule  450  to rupture, expelling powder  460 . 
     A user continues to push sheath  420  distally, causing powder  460  to contact a distalmost end of end effector  430 . Sheath  420  is then maneuvered to face target site T in any manner described herein, e.g., via articulation of articulation section  422 , urging end effector  430  toward target site T. End effector  430  tamps or pushes powder  460  against target tissue T. Powder  460  may be activated by moisture, e.g., a mucosal fluid at target site T and/or fluid sprayed via openings  24   a,    26   a.  After a predetermined time period has elapsed, sheath  420  is moved proximally, causing end effector  430  move back into lumen  22 . 
     An actuation device  540  for dispensing powder and/or a capsule  550  is shown in  FIG. 9 . Actuation device  540  includes a body  542  having a pistol-shaped grip and a trigger mechanism  546 . A fluid connector  544  connects actuation device  540  to a pressurized fluid source  570 , e.g., CO 2 , via a hose  572  (e.g., a flexible hose). Fluid source  570  may be a pressurized fluid source in a hospital, or fluid source  570  may be a device attached directly to actuation device  540 , allowing actuation device  540  to be portable. 
     Fluid connector  544  is connected to internal chamber  548 , which may contain capsule  550  or a powder not contained within a capsule. Capsule  550  may be added individually, or a hopper or other container (not shown) may be attached to actuation device  540  to supply capsules or powder to internal chamber  548 . A catheter connector  549  may connect a catheter  520 , having a lumen  522 , to body  542 . Once trigger mechanism  546  is actuated, a propellant fluid, e.g., CO 2 , is released from pressurized fluid source  570 , and may transmit capsule  550  distally down lumen  522  to an outlet (not shown) at a distal end of catheter  520 . According to an example, an amount of gas released may be approximately 16 liters or less, e.g., equal to an amount of gas, such as CO 2 , stored in two standard cartridges, at a pressure of approximately 1 to 10 Standard Liters per Minute (SLPM), or approximately 5 SLPM. This amount of propellant gas is sufficient to transmit capsule  550  along lumen  522 , while also being a safe amount of propellant fluid to supply to a body that is insufflated. 
     An operation of actuation device  540  will now be described. 
     Capsule  550  is loaded into internal chamber  548 . Catheter  520  is introduced to a body via a natural orifice or an incision and advanced to a target site. Once the distal end of catheter  520  is positioned adjacent the target site, the user actuates trigger mechanism  546 , causing propellant fluid to exit fluid source  570  and enter internal chamber  548 . The propellant fluid causes capsule  550  to travel distally from internal chamber  548  to the target tissue via catheter  520 . The propellant fluid is sufficient to transmit capsule  550  along catheter  520 , while being a safe amount of propellant fluid to introduce to a body that is insufflated. Additional capsules  550  may be transmitted to the same or different target sites until the treatment is complete, at which point catheter  520  is removed from the body. 
     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 capsules and/or transmitted in powder form to be expelled from the application device to a target location, including but not limited to materials having therapeutic effects. Additionally, or alternatively, unless otherwise specified, the medical device described herein may be formed of any metal, alloy, 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.