GB2603123A

GB2603123A - A Deployment Applicator for a Vacuum Therapy Device

Info

Publication number: GB2603123A
Application number: GB2100881.8A
Authority: GB
Inventors: Hindmarsh Andrew; Licence Sean; Farrow Adam; Ellis Richard; Grimm Russell; Morris Ellie
Original assignee: Cambridge University Hospitals NHS Foundation Trust
Current assignee: Cambridge University Hospitals NHS Foundation Trust
Priority date: 2021-01-22
Filing date: 2021-01-22
Publication date: 2022-08-03
Also published as: GB202100881D0; WO2022157511A1

Abstract

A vacuum therapy device, for treating an abscess or other internal defect, comprises a porous medium, e.g. foam or mesh, deployable through the distal end of a catheter and a deployment applicator 200 arranged to provide selective distal movement of the porous medium, e.g. via a suction tube (130, Fig. 1) connected to the porous body and moved by the applicator. The deployment applicator’s actuation mechanism is connectable to the porous pad via a movable element, e.g. the suction tube, and has a releasable drive lock selectively preventing proximal retraction of the pad. A disengagement mechanism releases the lock to enable proximal movement of the porous medium during reloading for redeployment. In a preferred embodiment, a hand-actuated lever 260 distally advances a double-sided toothed rack 230 by means of a ratchet 250 engaging one side 231 of the rack, the suction tube is coupled to the other side 232 of the rack by another ratchet 242, and both pawls are disengageable by rotating an interposed oval shaft (244, Fig. 3) actuated by another lever 240, allowing withdrawal of the rack and suction tube, e.g. using a projecting hand grip (238, Fig. 3).

Description

A Deployment Applicator for a Vacuum Therapy Device

Technical Field

The present disclosure relates to the technical field of vacuum therapy devices and methods for treatment of defects internal of a human or animal body, such as abscesses and abscess cavities. In particular, the present disclosure relates to a deployment applicator for controlling operation of a vacuum therapy device.

Background

Abscess cavities may include breaches in the continuity of the wall of the upper and lower gastrointestinal (GI) tract, which can create internal defects known as 'leak cavities'. Such breaches may be a result of anastomotic leak or spontaneous / iatrogenic perforation, which can often result in severe sepsis. Traditionally, open surgery and/or radiological drainage is required to treat such defects, though this approach is often associated with high rates of morbidity and mortality, and furthermore may not always be feasible. It is estimated that around 50% of patients who have a leak from the upper gastrointestinal (GI) tract that requires surgical intervention do not recover.

Abscesses occurring in the peritoneal and pleural cavities usually occur due to bacterial infection within that cavity, for example following visceral perforation in the peritoneal cavity, such as perforated appendicitis or perforated diverticulitis, or following pneumonia or other insult such as penetrating trauma in the pleural cavity. It is recognised that drainage of the cavity (i.e. removing contaminants) can help to control infection at these internal defects, though drainage by way of surgery is associated with increased morbidity and mortality.

It is desirable to provide an apparatus and method for treating such internal defects that may avoid the need for open surgery.

WO 2017/182827 Al discloses devices and methods for treatment of internal defects of a human or animal body. It discloses a catheter including a tube, an applicator and a porous medium, wherein the applicator can be controlled at a proximal end of the tube to deploy the porous medium from a distal end of the tube to treat the defect.

Summary

Aspects of the disclosure are set out in the independent claims and optional features are set out in the dependent claims. Aspects of the disclosure may be provided in conjunction with each other, and features of one aspect may be applied to other aspects.

In an aspect, there is provided a deployment applicator for a vacuum therapy device, the vacuum therapy device having a catheter for insertion into a human or animal body and a porous medium movable between a proximal position in which a majority of the porous medium is within the catheter and a distal position external to the catheter. The deployment applicator is configured to control distal movement of a said porous medium relative to a said catheter. The deployment applicator comprises: a drive mechanism configured to move from a first position to a second position in response to actuation of the applicator by a user; a movable element arranged to couple the drive mechanism to said porous medium so that movement of the drive mechanism from the first position to the second position provides distal movement of said porous medium relative to said catheter; a drive lock configured to inhibit movement of the drive mechanism from the second position back towards the first position; and a disengagement mechanism configured to disengage the drive lock to enable movement of the drive mechanism from the second position back to the first position for reloading the applicator for a subsequent deployment of a said porous medium from a said catheter.

Embodiments of the present disclosure may enable more controlled delivery of a porous medium from a catheter for treating a defect. Embodiments may prevent any unintentional retraction of said porous medium (e.g. proximal movement of the porous medium relative to the catheter). Embodiments may also enable the distal movement of the porous medium to be precisely controlled based on actuation of the applicator. For instance, the total distance of distal deployment of the porous medium relative to the catheter may be controlled precisely depending on the number of times the device was actuated. Deployment applicators of the present disclosure may also be actuated multiple times with different vacuum therapy devices (and different catheters/porous media). For example, after each deployment of a porous medium, the catheter/porous medium may be disconnected from the applicator, and the applicator may be reset to enable subsequent use of the device. For example, to reload the applicator, the drive mechanism may be moved back to its initial position (e.g. the first position), and/or a movable element may be reinserted into the device for controlling movement of the porous medium.

The drive mechanism may comprise a drive block connected to the movable element. The drive block may be arranged to move in response to actuation of the applicator thereby to move the movable element to provide distal movement of said porous medium relative to said catheter. The drive lock may be coupled to the drive block to inhibit movement of the drive block from the second position back towards the first position, thereby to inhibit proximal movement of said porous medium relative to said catheter. The disengagement mechanism may be configured to uncouple the drive lock from the drive block to enable movement of the drive block from the second position back towards the first position. The disengagement mechanism may comprise a disengagement shaft arranged to be movable into a disengaging position where it urges the drive lock away from the drive block. The disengagement shaft may be shaped to be rotated from a locking position in which the drive lock inhibits movement of the drive block to an unlocking position in which the disengagement shaft urges the drive lock away from the drive block.

The deployment applicator may comprise a mechanical actuator, such as a trigger, arranged to be actuated by a user to provide movement of the drive mechanism from the first position to the second position. The mechanical actuator may be arranged to provide movement of the drive block. The deployment applicator may comprise a bias configured to return the mechanical actuator to its non-actuated position in the absence of actuation of the actuator. The applicator may comprise a catheter lock operable to inhibit movement of said catheter relative to the deployment applicator. The movable element may be connected to a tube which runs inside the catheter for coupling the movable element to the porous medium. The movable element may comprise a push rod. The catheter lock may be configured to inhibit movement of said catheter while enabling distal movement of the tube inside the catheter. The catheter lock may be movable from an unlocked position to a locked position in which the catheter lock clamps said catheter to inhibit movement thereof.

The deployment applicator may comprise a drive block engagement member arranged to interact with a first surface of the drive block to: (i) provide movement of the drive block from the first position to the second position in response to actuation of the applicator by a user, and (ii) permit movement of the drive block engagement member relative to the drive block in a direction from the second position towards the first position. The drive block engagement member and the first surface of the drive block may have a ratchet-type engagement. The drive lock may comprise a non-return drive block arranged to interact with a second surface of the drive block to: (i) inhibit movement of the drive block from the second position towards the first position, and (ii) permit movement of the drive block from the first position to the second position. The non-return drive block and the second surface of the drive block may have a ratchet-type engagement. The ratchet-type arrangement of the drive block engagement member and the first surface of the drive block may be arranged in a different (e.g. opposite) direction to the ratchet-type arrangement of the non-return drive block and the second surface of the drive block. For example, the ratchet-type arrangement of the drive block engagement member and the first surface of the drive block may be configured to enable movement of the drive block engagement member relative to the drive block in a direction from the second position towards the first position while inhibiting relative movement in the opposite direction. For example, the ratchet-type arrangement of the non-return drive block and the second surface of the drive block may be configured to enable movement of the drive block relative to the non-return drive block in a direction from the first position to the second position while inhibiting relative movement in the opposite direction.

The disengagement mechanism may comprise a disengagement member movable from: (i) a first position in which the drive lock is engaged to inhibit movement of the drive mechanism from the second position back to the first position, to: (ii) a second position in which the drive lock is disengaged to permit movement of the drive mechanism from the second position back to the first position. The movement of the disengagement member from the first position to the second position may comprise a rotation. The disengagement member may be configured to be rotated from the first position to the second position. The disengagement member may be biased towards being in at least one of the first and second positions.

The applicator may comprise a retraction flange coupled to the drive mechanism and protruding from a side of the applicator. The retraction flange may be configured to be pulled to move the drive mechanism from the second position towards the first position in the event that the disengagement mechanism has disengaged the drive lock. The applicator may be arranged to limit distal movement of said porous medium relative to said catheter to a first threshold distance for each individual actuation of the deployment applicator. The applicator may be arranged to limit distal movement of said porous medium relative to said catheter to a second threshold distance for the cumulative distance provided by a plurality of actuations of the deployment applicator. For example, the applicator may be configured so that, in response to one complete actuation of the applicator (e.g. one full squeeze of the trigger), the drive mechanism may move from the first position to the second position, e.g. it may move the first threshold distance. In response to subsequent actuations of the applicator, the drive mechanism may keep moving in the same direction until the second threshold distance is reached. After the second threshold distance has been reached, subsequent actuations of the device will provide no further movement of the drive mechanism (and thus of the porous medium relative to the catheter).

In an aspect, there is provided a vacuum therapy device for treatment of a defect internal of a human or animal body. The device comprises: a porous medium for treatment of the defect; a catheter having a proximal end and a distal end, wherein the catheter is configured to be inserted into the body to enable deployment of the porous medium through an opening at the distal end for treatment of the defect; and a deployment applicator configured to control distal movement of the porous medium relative to the catheter. The deployment applicator is configured to: (i) selectively provide distal movement of the porous medium relative to the catheter, and (ii) inhibit proximal movement of the porous medium relative to the catheter. The deployment applicator of this aspect may comprise any deployment applicator of the present disclosure. The movable element of the deployment applicator may be connected to the porous medium via a tube which runs inside the catheter. The tube within the catheter may also be configured to provide suction at the porous medium.

Figures Some examples of the present disclosure will now be described, by way of example only, with reference to the figures, in which: Figs. la and lb show schematic diagrams of an exemplary vacuum therapy device.

Fig. 2 shows a schematic diagram of an exemplary deployment applicator for a vacuum therapy device, such as the exemplary vacuum therapy device of Figs la and lb. Figs. 3a and 3b show schematic diagrams of an exemplary drive lock and disengagement mechanism for a deployment applicator, such as for the exemplary deployment applicator of Fig. 2.

In the drawings like reference numerals are used to indicate like elements.

Specific Description

Embodiments of the present disclosure are directed to a deployment applicator for a vacuum therapy device. The deployment applicator may be used with a vacuum therapy device which includes a porous medium and a catheter. For such devices, the porous medium may be moved relative to the catheter so that the porous medium can be delivered into a defect internal of a human or animal body for treatment of that defect. Deployment applicators of the present disclosure are configured to provide greater control of the movement of the porous medium relative to the catheter. For instance, the deployment applicators of the present disclosure are arranged to allow a user to actuate the device to initiate movement of the porous medium in a first direction (e.g. movement of the porous medium out from the distal end of the catheter), while inhibiting any subsequent movement of the porous medium in the opposite direction (e.g. movement of the porous medium back into the catheter). The deployment applicator includes a disengagement mechanism which allows the applicator to be reset to enable a subsequent use of the applicator. Once the disengagement mechanism has been actuated, the applicator may be reset by a physician providing reverse movement of a drive block of the applicator (e.g. to restore the drive block to its original position). The deployment applicator may enable greater precision when incrementally moving the porous medium in the first direction.

Deployment applicators of the present disclosure will be described in more detail below.

These deployment applicators are configured to be used with vacuum therapy devices to control movement of a porous medium of such a vacuum therapy device relative to a catheter of the device. To help illustrate the functionality of such deployment applicators, set out below is a description of exemplary vacuum therapy devices with which deployment

applicators of the present disclosure may be used.

Figs. la and lb show an exemplary vacuum therapy device 100. The vacuum therapy device 100 includes a catheter 110, a suction element comprising an inner tube 120 and a suction tube 130, and a porous medium 140. In Fig. la, the device 100 is in an insertion position with the porous medium 140 inside the catheter 110. In Fig. 1 b, the device 100 is in a deployed position with the porous medium 140 outside the catheter 110.

The inner tube 120 is located within the catheter 110. The inner tube 120 is connected to the suction tube 130 at connection 125. The suction tube 130 is located distally of the inner 35 tube 120. The suction tube 130 is connected to the porous medium 140 by being arranged within a hollow passageway of the porous medium 140. The suction tube 130 extends through the porous medium 140 to a distal end of the porous medium 140.

The vacuum therapy device 100 in this example is an endoscopic vacuum therapy (EVT) device. Endoscopic vacuum therapy is a relatively new technique for treating defects, such as oesophageal perforation and certain other leakages from the UGI tract, such as post-operative leakages. EVT is a minimally invasive, alternative method of treatment to traditional surgery, utilising vacuum-assisted closure (VAC) techniques. EVT involves placing a porous medium, such as a polyurethane sponge, into a defect cavity under endoscopic visualization and then applying a continuous negative pressure, causing the cavity to collapse around the sponge. The sponge is typically changed every 48-72 hours until the cavity shrinks and stable granulation tissue forms a barrier.

EVT includes three different stages for treating a gastrointestinal defect. For example, EVT may be used to treat a defect in the oesophagus. To treat the defect, a tube may be inserted through the nose or mouth and then directed to the defect under direct endoscopic visualisation. A porous medium may be carried into the patient in the tube and then placed in the defect cavity, or a lumen proximal thereto, such as a lumen of the bowel (e.g. for intra-luminal vacuum therapy). A negative pressure, such as -125mm Hg, may then be applied, causing the defect cavity to collapse around the porous medium to aid healing.

This treatment may also be referred to as endoscopic transluminal' or Intraluminar vacuum therapy.

The catheter 110 is elongate and tubular. The catheter 110 has a proximal end and a distal end. The distal end is the end which is to be inserted into the body and located at, or proximal to, the defect. The proximal end is the end which will be located towards the physician. To deliver the catheter 110 to a target location within the body, the catheter 110 may be inserted into an endoscope, or the catheter 110 may be attached to an endoscope external to the endoscope. For examples where the catheter 110 may be inserted into an endoscope, the catheter 110 may have an outer diameter sized to fit within an endoscope, such as within a working channel of an endoscope. The outer diameter may be sized to enable the catheter 110 to move relative to the endoscope when inside the endoscope. For example, the outer diameter may be less than 2.8mm or 3.7mm, depending on the endoscope with which the catheter 110 is to be used. For examples where the catheter 110 may be attached to the endoscope external to the endoscope (e.g. the two may be adjacent to one another and affixed together), the catheter 110 may be provided with one or more attachment means (e.g. sutures) for affixing the catheter 110 to the endoscope. The catheter 110 is of sufficient length to extend from outside the body to a location proximal to (or inside) the defect in the body. For example, the tube may have a length of between 0.5 m and 1.5 m depending on the patient and the location of the defect in the patient. A distal end of the catheter 110 is flared open (e.g. tapered to a larger diameter).

The inner tube 120 is elongate and tubular. An outer diameter of the inner tube 120 is sized to enable the inner tube 120 to fit within the catheter 110 (and to move relative thereto). The distal end of the inner tube 120 is located within the catheter 110 proximal to the distal end of the catheter 110. The distal end of the inner tube 120 is connected to a proximal end of the suction tube 130 at the connection 125. The inner tube 120 is of sufficient length to extend from outside the body to a location proximal to the defect. The inner tube 120 is provided by a coiled wire. The helical structure of the coiled wire extends along a longitudinal axis of the inner tube 120 thereby providing the hollow cross-section defining the tubular structure.

The suction tube 130 is elongate and tubular. The suction tube 130 is of sufficient length to extend into a hollow passageway of the porous medium 140 to connect the suction tube 130 to the porous medium 140. The suction tube 130 extends along a majority of the length of the porous medium 140. A distal tip of the suction tube 130 is located proximal to a distal end of the porous medium 140. The suction tube 130 is adhered to the porous medium 140 at a plurality of positions along its length. The suction tube 130 is tapered so that the distal end of the suction tube 130 is at a smaller diameter, e.g. the suction tube 130 has a larger diameter in a middle region along the length of the suction tube 130 than that at the distal end of the suction tube 130.

The connection 125 between the suction tube 130 and the inner tube 120 comprises a screw thread type connection. The inside surface of the suction tube 130 at its proximal end includes a female screw thread. The coiled wire at the distal end of the inner tube 120 effectively provides a male screw thread. The coiled wire is screwed into the suction tube 130. Adhesive may also be used in this region for the attachment. The connection 125 between the suction tube 130 and the inner tube 120 is in the region of the suction tube 130 with the larger diameter.

The porous medium 140 has a hollow passageway in which the suction tube 130 is provided and connected thereto. The porous medium 140 is sized so that it is compressible to fit within the catheter 110 The porous medium 140 comprises a material having pores which are typically of a size between 400 to 600 microns. The porous medium 140 may include one or more materials such as: (i) foams e.g. a polyurethane foam, (ii) expandable meshes e.g. a wire mesh, (iii) bio-active materials e.g. bio-active collagen. For example, the wire mesh may be formed of a shape memory material, such as a nickel titanium alloy (e.g. nitinol).

The vacuum therapy device 100 is configured for insertion into a patient to be delivered to, or proximal to, a defect internal of the patient's body. In this example, the vacuum therapy device 100 is an endoscopic vacuum therapy device. The device 100 is arranged (e.g. sized and shaped) to be carried into the patient's body using an endoscope. For example, the device 100 may be arranged to be insertable into an endoscope, and/or the device 100 may be arranged so that it may be affixed to an endoscope (e.g. via suture so that the two are adjacent). The device 100 is configured so that when inserted into the patient with an endoscope, the endoscope and device 100 (e.g. the endoscope housing the device 100, or the endoscope adjacent the device 100) may pass through bends in the internal lumens of the patient. For example, the device 100 may be configured for treatment of defects in a patient's gastrointestinal tract. For this, the device 100 is configured to be inserted into a patient's nose (or their mouth, such as when the patient is already being ventilated).

The device 100 is sufficiently flexible to pass round the bends on the way from the patient's nose or mouth into the defect their gastrointestinal tract. The device 100 is arranged to be resistant to kinking during insertion into the patients gastrointestinal tract. The device 100 may be arranged to facilitate movement of the device 100 within a said endoscope (e.g. an outer surface of the device 100 may be configured to reduce friction with an endoscope, such as by having a friction-reducing coating). The device 100 may be arranged so that the endoscope and device 100 are separable when inside the patient (e.g. in response to force being applied to one of the endoscope or device 100, such as to tear the suture, or by use of endoscopic graspers which may be used, e.g. opened, to release the suture). For example, the device 100 may be configured so that it is capable of twisting or bending with a radius of curvature of approximately 10mm, such as 20mm or less. For example, the device 100 may be configured to bend round 90 degrees or more without rupturing or kinking.

The catheter 110 is configured to be inserted into a patient. The catheter 110 is of sufficient flexibility to pass round bends in body lumens of a patient. The catheter 110 is arranged to avoid kinking during insertion into the patient. An inner surface of the catheter 110 may be configured to reduce friction between that inner surface and components inside the catheter 110 (e.g. the inner tube 120, suction tube 130 and/or porous medium 140). For example, the catheter 110 may have a friction reducing coating on its interior surface, such as an inner lining, e.g. made of fluorinated ethylene propylene. The inner lining may be adhered, or sewed, to the inside of the catheter, and/or it may just sit within the catheter without being affixed thereto. A distal end of the catheter 110 may be configured to facilitate insertion (e.g. retraction) of a porous medium 140 into the catheter 110. For example, the distal end may be flared open The inner tube 120 is configured to be inserted into the catheter 110 and into a patient. The inner tube 120 is configured to be of sufficient flexibility to pass round bends in body lumens of a patient. The inner tube 120 is configured to maintain a sufficient fluid seal so that some of the negative pressure applied to a proximal end of the inner tube 120 is transmitted to a proximal end of the inner tube 120. It is to be appreciated that where the inner tube bends, it may not provide a fluid tight seal, and so negative pressure will also be present inside the catheter (e.g. in regions inside the catheter but outside the inner tube 120). Negative pressure may therefore be transmitted to the suction tube 130 (from the inner tube 120 through the connection 125), as well as to a proximal side of the porous medium 140 (through the catheter 110).

The inner tube 120 is configured to move relative to the catheter 110. The inner tube 120 is configured to pass round bends -for example, the coil wire may provide increased flexibility as compared to a continuous tube of material. The inner tube 120 may be configured to reduce friction between the inner tube 120 and the catheter 110. For example, the outer surface of the inner tube 120 may have a coating for reducing friction between it and the inner surface of the catheter 110. The inner tube 120 may be formed of a biocompatible material and/or may be coated by a bio-compatible substance.

Although not shown in the figures, the inner tube 120 may be connected to a source of negative pressure at its proximal end. For example, a common connector may connect both the inner tube 120 and the catheter 110 to the source of negative pressure. This connection to the source of negative pressure may be direct or indirect (via one or more additional components for transmitting negative pressure). The device 100 is configured to transmit such negative pressure, so that it may be applied at the porous medium 140 to provide suction thereat. For example, a proximal end of the inner tube 120 (and/or a proximal end of the catheter 110) may be secured to an adaptor for connection to a source of negative pressure, such as a vacuum apparatus. The device 100 may be arranged so that when in use, such an adaptor is located outside of the patient's body. The adaptor may provide a connector for coupling the inner tube 120 with the vacuum apparatus. The adaptor may be provided with a further connector, which is substantially in-line with the connector, for coupling with a flexible tube (e.g. formed from FEP). The further connector may be provided with barbs, which a flexible tube may be stretched over so as to provide a secure fluid-tight coupling The connection 125 between the suction tube 130 and the inner tube 120 is configured to provide a fluid tight seal so that negative pressure may be provided from the inner tube 120 to the suction tube 130 to enable suction to be provided through the suction tube 130 at a distal end of the porous medium 140. The device 100 is arranged so that air or other substances drawn into the suction tube 130 pass up through the suction tube 130 into the inner tube 120 (and also into the catheter 110) and out the proximal end of the inner tube 120/catheter 110. The inner tube 120 is connected to the suction tube 130 (and the suction tube 130 connected to the porous medium 140) so that movement of the suction tube 130 and porous medium 140 can be controlled by movement of the inner tube 120. The device 100 is arranged to enable a physician to interact with the inner tube 120 (or a component coupled with the inner tube 120) at a proximal location, e.g. outside the patient's body, to control movement of the suction tube 130 and porous medium 140 at a distal location, e.g. in or near to the defect internal of the patient. This movement of the inner tube 120/suction tube 130/porous medium 140 relative to the catheter 110 may be controlled by deployment applicators of the present disclosure as described herein.

The suction tube 130 is configured to provide suction at the porous medium 140. The suction tube 130 is configured to receive air or other substances which are transmitted into the suction tube 130 through the porous medium 140 and to transmit these away through the inner tube 120. The suction tube 130 is configured to be flexible with an atraumatic tip (e.g. to inhibit the suction tube 130 from causing damage to a patient when being moved around inside the patient). An outer surface of the suction tube 130 may be coated with an adhesive to facilitate a stronger connection between the suction tube 130 and the porous medium 140. A tip of the suction tube 130 may be coupled (e.g. via a wire or suture) to a component at a proximal location in the device 100 (such as the inner tube 120) to improve control of the movement of the suction tube 130, such as to facilitate removal of the suction tube 130 and porous medium 140 from a defect.

The porous medium 140 is arranged to be moved from a first position within the catheter 110 to a second position outside the catheter 110. In the first position, a portion of the porous medium 140 may still protrude from the end of the catheter 110, such as to provide a softer leading edge for insertion of the device. The porous medium 140 is configured so that it may be compressed to a volume which fits inside the catheter 110 and which may move within the catheter 110. For example, the porous medium 140 may be an open pore sponge, or a mesh which is capable of being unravelled, stretched out, or drawn out into a single thread of wire and which will return to its intended (e.g. normal, non-compressed) form when released. When the constraints on the volume of the porous medium 140 are reduced (e.g. when less of it is inside the catheter 110), it will adopt an expanded state having a larger volume. The porous medium 140 is configured to have a selected shape when in its expanded shape, and the porous medium 140 will adopt this selected shape when in its expanded shape, despite the shape it has when in a compressed state (inside the catheter 110). The porous medium 140 is configured to be of sufficient flexibility so that a catheter 110 housing the porous medium 140 may pass round bends in the body lumen of the patient.

The porous medium 140 is arranged to facilitate treatment of the defect internal of the human body by application of a negative pressure (e.g. providing suction) through the porous medium 140 at the defect. The device 100 may be configured so that suction is applied to the environment surrounding the porous medium 140. The porous medium 140 may be configured to facilitate tissue ingrowth for tissue in and around the defect. Tissue in the environment of the porous medium 140 may be drawn towards the porous medium 140 (due to the suction), and the porous medium 140 is configured to be biocompatible for tissue coming into contact therewith.

To prepare the device 100 for insertion into the patient, the suction tube 130 is inserted within the porous medium 140, and the inner tube 120 is connected to the suction tube 130. The porous medium 140 is compressed and inserted within the catheter 110. The inner tube 120 and/or the catheter 110 is connected to a vacuum apparatus. An outer surface of the catheter 110 may be lubricated. The device 100 is inserted into an endoscope or affixed to the endoscope. The endoscope and device 100 are then inserted into the patient. For this, the device may be inserted through a patient's nose before being pulled out their mouth and then affixed to an endoscope (for insertion). For treatment of defects in the upper gastrointestinal tract, the device 100 will be inserted into the patient's nose or mouth.

The device 100 may be passed through the patient's nose then out their mouth prior to insertion into an endoscope, or the device 100 may be inserted through the patient's mouth (e.g. in an endoscope). The pair may then be guided (e.g. under endoscopic visualisation) through the patient's gastrointestinal tract towards the defect. Depending on the size and/or location of the defect, the device 100 will be inserted either into the defect, or to a location proximal to the defect (close enough so that the porous medium 140 may be delivered from the catheter 110 and into the defect, or into a suitable position for treatment of the defect, e.g. for intraluminal use). The endoscope may be removed leaving the device 100 inside the patient's gastrointestinal tract, or the endoscope may remain to facilitate insertion of the porous medium 140 into the defect (e.g. the endoscope may be removed once the porous medium 140 is arranged in the correct location in the defect, such as once negative pressure is applied to the device, and the porous medium is held in place in the cavity by virtue of this negative pressure).

Once the device 100 is located at the desired location, the porous medium 140 is moved out of the catheter 110. This involves controlling movement of the suction tube 130 by moving either the tube itself, or a component connected to the tube. This movement will be controlled from a location outside the patient, such as by pushing a proximal end of the inner tube 120 (e.g. using a deployment applicator of the present disclosure). The porous medium 140 is then pushed out of the catheter 110, where it begins to expand to its selected shape at its uncompressed volume. The amount of volume required, and thus the amount by which the porous medium 140 is pushed out of the catheter 110 may vary depending on intended use, and this may be controlled by the physician (e.g. using deployment applicators of the present disclosure). The porous medium 140 will then be in its intended location once deployed inside the defect, or in a suitable position for treatment of the defect, e.g. for intraluminal use. Once at this intended location, negative pressure is applied from the vacuum apparatus. This negative pressure is effectively transmitted through the inner tube 120/catheter 110 to the suction tube 130 to provide suction at the porous medium 140, and in its surrounding environment. This suction draws in tissue in the region surrounding the defect, to help heal the defect. For example, this may comprise closure of any 'dead space'.. After this, any fluids or other substances from the cavity may be drained, such as draining of sepsis. Such a device may also provide improved source control, e.g. to prevent further leakage into the cavity. Tissue granulation may then subsequently occur at the defect and this may promote healing. Any material passed through the porous medium 140 and into the suction tube 130 will also be drawn up through the inner tube 120 and out the patient.

After a selected amount of time has passed (typically 48 to 72 hours), the device 100 will be removed from the patient. For this, suction may be stopped. The porous medium 140 will be retracted, such as by pulling at a proximal end of the inner tube 120. The porous medium 140 will be pulled out the leak cavity by pulling the entire device 100 proximally, e.g. by pulling the catheter 110 and the inner tube 120, such as at their proximal end. The wire or suture connecting the inner tube 120/suction tube 130 to the tip region of the porous medium 140 may facilitate a more uniform distribution of the pulling force to the different regions of the porous medium 140. This may enable the porous medium 140 to be pulled more cleanly out from the defect. For example, some tissue ingrowth may occur into the porous medium 140 which may make it harder to pull out the porous medium 140. A solution, such as saline, may be flushed through the catheter 110 to help removal of any ingrown tissue onto the porous medium 140. Once the porous medium 140 has been removed from the cavity, it may be retracted back into the catheter 110. The tapered distal end of the catheter 110 may facilitate re-compression of the porous medium 140 for reinsertion into the catheter 110. Once the porous medium 140 is back in the catheter 110, the catheter 110 is retracted from the patient.

Deployment applicators of the present disclosure may be arranged to provide controlled movement of the porous medium 140 relative to the catheter 110. An exemplary deployment applicator of the present disclosure will now be described with reference to Figs. 2 and 3.

Fig. 2 shows a deployment applicator 200. The deployment applicator 200 has an opening 210 through which a catheter (e.g. catheter 110 as described above), and a tube within that catheter (e.g. inner tube 120 as described above), may pass.

The deployment applicator 200 includes a drive mechanism. The drive mechanism comprises a drive block 230. The drive block 230 has a first surface 231 and a second surface 232. The drive mechanism also includes a driving flange 234. Although not shown in Fig. 2, the driving flange 234 may be connected to a moveable element such as a push rod, e.g. the driving flange may abut the push rod. The drive mechanism may also comprise one or more movable element guides 236. The movable element may be connected to the inner tube which goes inside the catheter in a region 215, as shown in Fig. 2.

The deployment applicator 200 also includes a drive lock, which comprises a non-return drive block 242. The drive lock may also comprise a safety rocker 220. The deployment applicator 200 includes a catheter lock 212, and a disengagement mechanism comprising a disengagement member 240.

The deployment applicator 200 also includes a handle 262, as well as a mechanical actuator which, in Fig. 2, is a trigger 260, and biasing means shown as a spring 264. The drive mechanism also includes a connection between the mechanical actuator and the drive block 230. The connection includes a drive block engagement member 250, as well as a sliding element 252 and a track 254 for the sliding element 252.

Fig. 3 shows the drive mechanism, the disengagement mechanism and the drive lock in more detail. The drive mechanism also includes a retraction flange 238. The disengagement member 240 of the disengagement mechanism also includes a disengagement shaft 244.

The opening 210 is located at a distal end of the applicator 200. The distal end of the applicator 200 comprises the end of the applicator 200 which will be located towards the patient (e.g. the end from which the catheter will extend in use). The driving flange 234 is located towards a proximal end of the applicator 200. The proximal end of the applicator 200 may comprise the end located towards the physician. The disengagement member 240 is located at the proximal end of the deployment applicator 200. The deployment applicator is shaped to define a catheter channel extending from the opening 210 at the distal end towards the proximal end of the applicator 200. The catheter channel extends from the opening 210 to the region 215. The movable element guides 236 are arranged between the region 215 and the proximal end of the deployment applicator 200. The movable elements are arranged to define a movable element channel. The movable element channel extends from the proximal end of the applicator 200 towards the distal end. The movable element channel extends from the proximal end to the region 215. The movable element channel runs parallel with the catheter channel. The moveable element channel is coaxial with the catheter channel. The movable element channel is aligned with the catheter channel so that a movable element moving in a distal direction along the movable element channel may push a tube inside a catheter in the catheter channel in the distal direction.

The catheter lock 212 is located proximal to the opening 210. The catheter lock 212 comprises material extending across the opening 210. The safety rocker 220 comprises a first portion arranged between the region 215 and the opening 210, and a second portion arranged towards the drive block 230 The safety rocker 220 is pivotally mounted to the deployment applicator 200.

The drive block 230 extends from a proximal region of the applicator 200 towards a distal region of the applicator 200. The drive block 230 runs parallel to the movable element channel. The drive block 230 is offset (e.g. laterally) from the movable element channel.

The driving flange 234 is connected to the drive block 230 at a proximal region of the drive block 230. The driving flange 234 extends from the drive block 230 and into the movable element channel. The driving flange 234 may comprise a mount for mounting a movable element onto the driving flange 234. The first and second surfaces of the drive block 230 contain gripping elements. These gripping elements may comprise a plurality of teeth. The teeth extend along a length of the drive block 230 from the proximal end to the distal end (for both the first and second surfaces). The second portion of the safety rocker 220 is located towards the distal end of the drive block 230. The first and second surfaces extend from the proximal region of the drive block 230 to the distal region. The second surface 232 is in a plane parallel to the movable element channel (as is the first surface 231). As can be seen in Fig. 3, the retraction flange 238 extends outwards from the driving block (e.g. at an angle to the direction running from the proximal end of the drive block 230 to the distal end).

The non-return drive block 242 comprises an arm which is located adjacent to the second surface 232 of the drive block 230. The arm extends from a body of the non-return drive block 242 which sits in a recess in the applicator 200. A body of the non-return drive block 242 may be fixedly retained in place in the deployment applicator 200. For example, the body may comprise one or more tabs configured to engage with corresponding recesses of the applicator 200 to retain the body in place (even when the arm may be moved in a direction away from the second surface 232 of the drive block 230). The arm of the non-return drive block 242 includes gripping elements, such as teeth. The teeth of the non-return drive block 242 correspond to those of the second surface 232 of the drive block 230.

The drive block engagement member 250 is located adjacent to the first surface 231 of the drive block 230. The drive block engagement member 250 comprises gripping elements, such as teeth. The teeth of the drive block engagement member 250 correspond to those of the first surface 231 of the drive block 230. The drive block engagement member 250 is connected to the sliding element 252. The sliding element 252 lies in the track 254. The trigger 260 is pivotally mounted to the applicator 200. The trigger 260 is connected to the spring 264, which is attached to the applicator 200. The spring 264 is attached to the handle 262 of the applicator 200. A handle portion of the trigger 260 is located on one side of the pivot and a driving portion of the trigger 260 is located on the other side of the pivot. The driving portion of the trigger 260 is adjacent to the sliding element 252 (e.g. the driving portion abuts the sliding element 252).

The disengagement member 240 is located at the proximal end of the applicator 200. The disengagement member 240 is in the form of a plate at the proximal end of the applicator 200. As can be seen in Fig. 3, the disengagement shaft 244 extends from the disengagement member 240 at the proximal region of the applicator 200 towards the proximal end of the applicator 200. The disengagement shaft 244 is coupled to the disengagement member 240 at the proximal end of the applicator 200. The disengagement shaft 244 runs parallel to the drive block 230. A proximal region of the disengagement shaft 244 is located proximal to the arm of the non-return drive block 242. A cross-section of the disengagement shaft 244 is arranged to be wider in one direction than in the other. The cross-section is selected so that rotation of the disengagement shaft 244 may rotate the shaft from a first position in which the disengagement shaft 244 is not in contact with the arm of the non-return drive block 242 (and the arm of the non-return drive block 242 is in contact with the second surface 232 of the drive block 230), and a second position in which the disengagement shaft 244 is in contact with the arm of the non-return drive block 242 (and the contact between the shaft and the arm is such that the arm is no longer in contact with the second surface 232 of the drive block 230).

The deployment applicator 200 comprises a movable element (not shown in the Figs.). The movable element is coupled to the driving flange 234 (e.g. via the mount of the driving flange 234). The movable element extends from the mount towards the distal end of the applicator 200. The movable element lies in the movable element channel. The movable element is held in place in the movable element channel by the movable element guides 236. The movable element is coupled to a tube which lies in a catheter, such as an inner tube. For example, the movable element may comprise a push rod, and the push rod may be attached to a tube, such as being welded to the tube. The tube may be an inner tube as described above. The tube lies in the catheter. The tube and catheter are connected to the movable element in the region 215. The tube and catheter extend distally from the region 215 along the catheter channel and out through the opening 210 of the applicator 200. When the tube and catheter are in the catheter channel, the catheter will lie on the safety rocker 220 so that the safety rocker 220 has pivoted such that the second portion of the safety rocker 220 does not abut the drive block 230.

The deployment applicator 200 is arranged to provide controlled movement of the inner tube/porous medium relative to the catheter (and the tube inside the catheter) in response to actuation of the trigger 260 of the device. The applicator 200 is arranged so that each actuation of the trigger 260 will cause a selected amount of movement of the catheter. After each movement of the catheter in the distal direction, the catheter will be prevented from moving backwards On the proximal direction) by the drive lock (the non-return drive block 242). The applicator 200 is configured to enable the drive lock to be disengaged by using the disengagement mechanism. Each time the trigger 260 is actuated, the trigger 260 will be restored to its original position for further actuation.

The applicator 200 is arranged for the drive block 230 to move in the distal direction in response to application of the trigger 260. The drive block engagement member 250 is arranged to interact with the first surface 231 of the drive block 230 so that movement of the drive block engagement member 250 in the distal direction causes a movement of the drive block 230 in the distal direction. For example, the teeth of the drive block engagement member 250 interact with the teeth of the first surface 231 of the drive block 230 so that movement of the drive block engagement member 250 in the distal direction causes movement of the drive block 230 in the distal direction. The drive block engagement member 250 and the drive block 230 are arranged so that movement of the drive block engagement member 250 in the proximal direction does not cause movement of the drive block 230 in the proximal direction. For example, the teeth of the first surface 231 of the drive block 230 may form a ratchet-type engagement with the teeth of the drive-block engagement member (e.g. to permit relative movement in one direction but not the other).

The drive block engagement member 250 is connected to the sliding element 252 so that the drive block engagement member 250 will move in the proximal/distal direction in response to movement of the sliding element 252 in the proximal/distal direction. The sliding element 252 is arranged to slide within the track 254 in either the proximal or distal direction. The sliding element 252 is arranged to engage with the driving portion of the trigger 260 to enable pivoting of the trigger 260 to drive a linear movement of the sliding element 252. For example, in response to actuation of the trigger 260, the sliding element 252 may move in the distal direction. After actuation, and once the user is no longer applying pressure to the trigger 260, the spring 264 is configured to return the trigger 260 to its position prior to actuation. The spring 264 is arranged to restore the trigger 260 to its pre-actuation position. As the spring 264 restores the trigger 260 to its pre-actuation position, the driving portion of the trigger 260 is arranged to slide the sliding element 252 in the proximal direction along the track 254. Due to the ratchet-type arrangement between the drive block engagement member 250 and the first surface 231 of the drive block 230, this proximal movement of the sliding element 252 (and thus also the drive block engagement member 250) will result in the teeth of the drive block engagement member 250 slipping over the teeth of the first surface 231 of the drive block 230 without causing the drive block 230 to move in the proximal direction.

The drive block 230 is arranged to move in the distal direction in response to actuation of the trigger 260. The drive block 230 is arranged so that movement of the drive block 230 in the distal direction will also provide movement of the driving flange 234 in the distal direction. The driving flange 234 is arranged so that movement of the drive block 230 in the distal direction (and thus movement of the driving flange 234 in the distal direction) cause the movable element to also move in the distal direction. The movable element is configured to be driven by the driving flange 234 to slide within the movable element channel (e.g. sliding through the movable element guides 236). The movable element is arranged to slide in the distal direction in the movable element channel in response to actuation of the trigger 260 by a user. The movable element is arranged to be connected to the tube that runs inside the catheter to transfer this distal movement of the movable element into distal movement of the tube.

The catheter lock 212 is configured to selectively lock the catheter so that it is held in a fixed position. The catheter lock 212 may operate in a first state in which movement of the catheter is permitted, and in a second state in which movement of the catheter is inhibited. The catheter lock 212 is configured to inhibit movement of the catheter (e.g. in the distal direction) while still permitting movement of the tube relative to the catheter. The catheter lock 212 is arranged so that, when actuated, the catheter will be retained in position and the tube inside the catheter may be advanced distally relative to the catheter (e.g. the tube may move within the catheter in a distal direction). For vacuum therapy devices of the present disclosure, movement of the tube inside the catheter in the distal direction will cause a distal movement of the porous medium (e.g. out a distal end of the catheter for treatment of a defect).

The catheter lock 212 may comprise a movable piece of material which may be moved from a first position in which it does not impede movement of the catheter, to a second position in 35 which it does (e.g. so as to impede movement of the catheter). For example, the catheter lock 212 may comprise a piece of material having a hole cut thereinto, where that hole has a first region with a first (larger) cross-sectional area through which the catheter may pass, and a second region (smaller) with a second (smaller) region which will clamp the catheter in place. The applicator 200 may comprise a groove in which the piece of material for the catheter lock 212 is placed. The catheter lock 212 may slide within this groove between two positions to permit or inhibit movement of the catheter. For example, the catheter lock 212 may be moved from a position in which the catheter runs through the first cross-sectional area of the hole to a second position in which the catheter is clamped within the second cross-sectional area of the hole. The piece of the material may be arranged so that it can be pushed into, or out of, its two positions, e.g. the device may be arranged to enable a user to push the material in a given direction to force the material to clamp the catheter in place (e.g. the user may push down on the material for clamping).

The deployment applicator 200 is selectively operable to inhibit movement of the tube inside the catheter in a proximal direction (e.g. movement of the porous medium back into the catheter). The drive lock is configured to selectively inhibit movement of the movable element in a proximal direction, thereby to inhibit movement of the tube inside the catheter in a proximal direction. The non-return drive block 242 is arranged to interact with the drive block 230 to inhibit movement of the drive block 230 (and thus movement of the driving flange 234 and movable element) in the proximal direction. The gripping elements (e.g. teeth) of the non-return drive block 242 are arranged to interact with the gripping elements (e.g. teeth) of the second surface 232 of the drive block 230 to permit movement of the drive block 230 in the distal direction, but to inhibit movement of the drive block 230 in the proximal direction. For example, the two sets of teeth may be arranged to form a ratchet-type engagement. The applicator 200 is arranged so that the teeth of the second surface 232 of the drive block 230 may therefore slide over the teeth of the non-return drive block 242 when moving in the distal direction, but the teeth would lock when trying to move the drive block 230 in the proximal direction. For example, the ratchet-type arrangement of the first surface 231 of the drive block 230 and the drive block engagement member 250 may be in the opposite direction to the ratchet-type arrangement of the second surface 232 of the drive block 230 and the non-return drive block 242.

The disengagement mechanism is arranged to selectively disengage the drive lock (thereby to enable movement of the drive block 230 in the proximal direction). The disengagement mechanism is arranged to move the non-return drive block 242 away from the second surface 232 of the drive block 230 to prevent the interaction between the second surface 232 of the drive block 230 and the non-return drive block 242 inhibiting movement of the drive block 230 in the proximal direction. The non-return drive block 242 may be configured to be biased towards the second surface 232 of the drive block 230 so that, when the disengagement mechanism is no longer disengaging the drive lock, the non-return drive block 242 reengages with the second surface 232 of the drive block 230 to prevent proximal movement of the drive block 230.

One example of such a disengagement mechanism is shown in closer detail in Figs. 3a and 3b. The disengagement member 240 is arranged to be grasped by a user of the device (e.g. it is located at a proximal end of the device, where it is accessible to a user holding the device). The disengagement shaft 244 extending from the disengagement member 240 is arranged so that, when rotated, the disengagement shaft 244 urges the non-return drive block 242 away from the second surface 232 of the drive block 230. For example, a cross-section of the disengagement shaft 244 may be shaped to be wider in one axis than another (e.g. it may be oval-shaped). The disengagement mechanism is arranged so that rotation of the disengagement member 240 causes the disengagement shaft 244 to move the non-return drive block 242 away from the second surface 232 of the drive block 230 to disengage the drive lock. The disengagement mechanism may be arranged so that rotation of the disengagement member 240 from a first angle (e.g. 0 degrees) to a second angle (e.g. 90 degrees) causes the drive lock to be disengaged. The disengagement member 240 may be biased towards one or both of the first and second angle to facilitate rotation between the two angles (e.g. when rotated towards the first/second angle, the disengagement member 240 may snap into place at the first/second angle).

The deployment applicator 200 is arranged so that actuation of the disengagement mechanism will enable the applicator 200 to be 'reset'. The applicator 200 is arranged so that, once the disengagement mechanism has been actuated, the applicator 200 may be returned to an initial operating state (e.g. prior to using the applicator 200 again). For example, the drive block 230 may be returned to its original position at the proximal end of the applicator 200, e.g. by pulling on the retraction flange 238. For example, a movable element may be placed at the proximal end of the movable element sliding channel.

With reference to Fig. 2 again, the applicator 200 may comprise the safety rocker 220, which is arranged to inhibit movement of the drive block 230 in the distal direction when no catheter is inserted into the applicator 200 (via the opening 210). The safety rocker 220 may be arranged to impede movement of the drive block 230 in the distal direction in the absence of a catheter in the applicator 200. For example, the safety rocker 220 may be rotatable between a first position where it obstructs movement of the drive block 230 in the distal direction, and a second position in which it does not obstruct this movement of the drive block 230. The safety rocker 220 may be arranged to extend into the catheter channel so that when a catheter is included in the catheter channel, it causes the safety rocker 220 to pivot so that it moves away from the drive block 230 (and therefore does not impede distal movement of the drive block 230). The safety rocker 220 may further ensure that the drive block 230 is in a proximal position when a catheter is inserted into the applicator 200 (although it is to be appreciated in the context of the present disclosure that the drive lock may provide this same functionality).

The applicator 200 is arranged to provide a limited amount of travel of the drive block 230/movable element (and thus a limited amount of movement of a porous medium relative to the catheter). For example, the applicator 200 may be arranged to provide a selected maximum amount of travel so that the porous medium only ever extends a selected amount from the end of the catheter. For example, the applicator 200 may be arranged so that, once the porous medium has been fully deployed (e.g. once a maximum travel of the movable element has occurred), a portion of the porous medium still remains inside the catheter. The applicator 200 may comprise one or more stopping tabs arranged to prevent any further distal movement of the movable element. For example, the movable element and/or the drive block 230 may have one or more tabs which will abut with a corresponding portion of the applicator 200 to prevent any further movement of the movable element/drive block 230. For example, the applicator 200 may be arranged to provide a maximum travel of 100 mm, such as under 90 mm, such as under 80 mm, such as approximately 60 mm of travel. The applicator 200 is arranged to provide only a selected amount of travel per each actuation of the applicator 200, e.g. per each squeeze of the trigger 260. For example, each squeeze may cause 20 mm or less of travel, such as 15 mm or less, such as 10 mm or less, such as 5 mm or less. Providing a limited amount of travel per each actuation may enable precise control over the movement of the porous medium within the patient.

An example of operation of deployment applicators of the present disclosure will now be described with reference to the applicator 200 shown in Figs. 2, 3a and 3b in combination with the vacuum therapy device 100 shown in Figs. la and 1 b.

In the manner described above, the catheter 110 will be inserted into the patient, and located in, or proximal to, the defect to be treated. At this stage, the porous medium 140 will be primarily inside the catheter 110 (e.g. a majority of the porous medium 140 will be located inside the catheter 110). The deployment applicator 200 is used to provide precise and controlled movement of the porous medium 140 from its position inside the catheter 110 towards the defect to be treated). For this, the inner tube 120 of the device 100 will be coupled to the movable element of the deployment applicator 200. For example, a proximal end of the inner tube 120 may be connected, such as welded, to the movable element.

Prior to actuation, the deployment applicator 200 will be in an initial state in which the drive block 230 and driving flange 234 are located at a proximal end of the applicator 200. The catheter 110 (with the inner tube 120 inside) is located within the deployment applicator 200 (e.g. it has been inserted through the opening 210 into the device 100). The inner tube 120 is connected to the movable element, and the movable element is coupled to the driving flange 234 (e.g. via the mount of the driving flange 234). Due to the catheter 110 being inside the deployment applicator 200, the safety rocker 220 is pivoted away from the position in which it obstructs distal movement of the drive block 230. The disengagement member 240 is in its non-disengaging position, so that the drive lock is engaged (e.g. the non-return drive block 242 is interacting with the second surface 232 of the drive block 230 to prevent movement of the drive block 230 in the proximal direction). The trigger 260 will be in position biased away from the handle 262 of the applicator 200 by the spring 264, and the drive block engagement member 250 will be engaged with the first surface 231 of the drive block 230, with the sliding element 252 in place on the track 254. The catheter lock 212 will be in its locking position so that the catheter 110 is clamped in place relative to the applicator 200, but the inner tube 120 is free to move within the catheter 110.

Once the physician is satisfied that the distal end of the catheter 110 is located in a suitable position in, or proximal to, the defect to be treated, the deployment applicator 200 will be actuated to control deployment of the porous medium 140 from the catheter 110.

For this, the trigger 260 will be squeezed (e.g. the user will have a hand on the handle 262, and they will pull the trigger 260 towards the handle 262 with that hand). Squeezing of the trigger 260 causes the trigger 260 to pivot about its pivotal attachment to the applicator 200.

On the opposite end of the pivot to the portion of the trigger 260 being squeezed, the trigger 260 will pivot about the pivotal attachment and cause the sliding element 252 to move in a distal direction along the track 254. The sliding element 252 will move a fixed distance for each full squeeze of the trigger 260. This movement of the sliding element 252 will also cause the drive block engagement member 250 to move in the distal direction by the same fixed distance, and due to the interaction between the first surface 231 of the drive block 230 and the drive block engagement member 250, this will cause the drive block 230 also to move by the same fixed distance in the distal direction. As the drive block 230 moves in the distal direction, the driving flange 234 will also move in that direction, and push with it, the movable element along the movable element channel. As the catheter 110 will be clamped in position by the catheter lock 212, the movable element will push the inner tube into the catheter 110 by the same fixed distance, thus causing the porous medium 140 to move distally at the distal end of the catheter 110 by this fixed distance.

This process may be performed using image guidance, usually using endoscopic visualisation rather than radiological guidance, to give an idea of the location of the porous medium 140 in the patient (e.g. relative to the defect to be treated). The physician may control the deployment based on an indication of the location of the porous medium 140 relative to the defect. For example, the actuation process may be repeated a plurality of times before the porous medium 140 has extended a desired distance from the distal end of the catheter 110. The deployment applicator 200 may have a selected limit for the total amount of travel of the movable element, and so the actuation process may be repeated until the physician is satisfied with the location of the porous medium 140, or until the total amount of travel has been reached.

Once the porous medium 140 has been suitably deployed, the catheter 110 and inner tube may be clamped to hold them in a fixed position, such that the inner tube 120 and catheter 110 cannot move independently of each other (e.g. to maintain a fixed displacement of the porous medium 140 relative to the catheter 110). This may facilitate retaining the porous medium 140 at its desired location in the patient. As described above, a vacuum may be applied to the inner tube 120/catheter 110 for providing vacuum therapy to the defect. This process may involve disconnecting the catheter 110 and the inner tube 120/movable element from the applicator 200, for connection to a vacuum source. To remove the catheter 110 from the applicator 200, the catheter lock 212 may be moved to a non-locking position, and the catheter 110 (and inner tube 120 and movable element) pulled out through the opening 210.

The applicator 200 may then be reset so that it is ready for subsequent use. For this, the disengagement mechanism is activated. To do this, the disengagement member 240 is rotated, which causes the disengagement shaft 244 to urge the non-return drive block 242 away from the second surface 232 of the drive block 230. In so doing, the drive lock is disengaged, and the drive block 230 may move in a proximal direction. The physician may then pull on the retraction flange 238 to bring the drive block 230 back to the proximal end of the applicator 200. The disengagement member 240 may then be rotated back to reengage the drive lock. The applicator 200 may then be re-loaded with a catheter 110/inner tube 120/movable element for subsequent deployment.

It is to be appreciated in the context of the present disclosure that, to the extent that certain methods may be applied to the living human or animal body, it will be appreciated that such methods may not provide any surgical or therapeutic effect. In addition, it will be appreciated that such methods may be applied ex vivo, to tissue samples that are not part of the living human or animal body. For example, the methods described herein may be practiced on meat, tissue samples, cadavers, and other non-living objects.

It will be appreciated from the discussion above that the examples shown in the figures are merely exemplary, and include features which may be generalised, removed or replaced as described herein and as set out in the claims. As will be appreciated by the skilled reader in the context of the present disclosure, each of the examples described herein may be implemented in a variety of different ways. Any feature of any aspects of the disclosure may be combined with any of the other aspects of the disclosure. For example, method aspects may be combined with apparatus aspects, and features described with reference to the operation of particular elements of apparatus may be provided in methods which do not use those particular types of apparatus. In addition, each of the features of each of the examples is intended to be separable from the features which it is described in combination with, unless it is expressly stated that some other feature is essential to its operation. Each of these separable features may of course be combined with any of the other features of the examples in which it is described, or with any of the other features or combination of features of any of the other examples described herein. Furthermore, equivalents and modifications not described above may also be employed without departing from the invention.

Other examples and variations of the disclosure will be apparent to the skilled addressee in

the context of the present disclosure.

Claims

Claims 1. A deployment applicator for a vacuum therapy device, the vacuum therapy device having a catheter for insertion into a human or animal body and a porous medium movable between a proximal position in which a majority of the porous medium is within the catheter and a distal position external to the catheter, wherein the deployment applicator is configured to control distal movement of a said porous medium relative to a said catheter, the deployment applicator comprising: a drive mechanism configured to move from a first position to a second position in response to actuation of the applicator by a user; a movable element arranged to couple the drive mechanism to said porous medium so that movement of the drive mechanism from the first position to the second position provides distal movement of said porous medium relative to said catheter; a drive lock configured to inhibit movement of the drive mechanism from the second position back towards the first position; and a disengagement mechanism configured to disengage the drive lock to enable movement of the drive mechanism from the second position back to the first position for reloading the applicator for a subsequent deployment of a said porous medium from a said catheter.
2. The deployment applicator of claim 1, wherein the drive mechanism comprises a drive block connected to the movable element; and wherein the drive block is arranged to move in response to actuation of the applicator thereby to move the movable element to provide distal movement of said porous medium relative to said catheter.
3. The deployment applicator of claim 2, wherein the drive lock is coupled to the drive block to inhibit movement of the drive block from the second position back towards the first position, thereby to inhibit proximal movement of said porous medium relative to said 30 catheter.
4. The deployment applicator of claim 3, wherein the disengagement mechanism is configured to uncouple the drive lock from the drive block to enable movement of the drive block from the second position back towards the first position.
The deployment applicator of claim 4, wherein the disengagement mechanism comprises a disengagement shaft arranged to be movable into a disengaging position where it urges the drive lock away from the drive block.
6. The deployment applicator of claim 5, wherein the disengagement shaft is shaped to be rotated from a locking position in which the drive lock inhibits movement of the drive block to an unlocking position in which the disengagement shaft urges the drive lock away from the drive block.
7. The deployment applicator of any preceding claim, wherein the deployment applicator comprises a mechanical actuator arranged to be actuated by a user to provide movement of the drive mechanism from the first position to the second position.
8. The deployment applicator of claim 7, as dependent on any of claims 2 to 6, wherein the mechanical actuator is arranged to provide movement of the drive block.
9. The deployment applicator of any of claims 7 or 8, wherein the deployment applicator comprises a bias configured to return the mechanical actuator to its non-actuated position in the absence of actuation of the actuator.
10. The deployment applicator of any preceding claim, wherein the applicator comprises a catheter lock operable to inhibit movement of said catheter relative to the deployment applicator.
11. The deployment applicator of any preceding claim, wherein the movable element is connected to a tube which runs inside the catheter for coupling the movable element to the porous medium, for example wherein the movable element comprises a push rod.
12. The deployment applicator of claim 11, as dependent on claim 10, wherein the catheter lock is configured to inhibit movement of said catheter while enabling distal movement of the tube inside the catheter.
13. The deployment applicator of claim 10, or any claim dependent thereon, wherein the catheter lock is movable from an unlocked position to a locked position in which the catheter lock clamps said catheter to inhibit movement thereof.
14. The deployment applicator of claim 2, or any claim dependent thereon, wherein the deployment applicator comprises a drive block engagement member arranged to interact with a first surface of the drive block to: (i) provide movement of the drive block from the first position to the second position in response to actuation of the applicator by a user, and (ii) permit movement of the drive block engagement member relative to the drive block in a direction from the second position towards the first position, for example wherein the drive block engagement member and the first surface of the drive block have a ratchet-type engagement.
15. The deployment applicator of claim 2, or any claim dependent thereon, wherein the drive lock comprises a non-return drive block arranged to interact with a second surface of the drive block to: CO inhibit movement of the drive block from the second position towards the first position, and (ii) permit movement of the drive block from the first position to the second position, for example wherein the non-return drive block and the second surface of the drive block have a ratchet-type engagement.
16. The deployment applicator of any preceding claim, wherein the disengagement mechanism comprises a disengagement member movable from: (i) a first position in which the drive lock is engaged to inhibit movement of the drive mechanism from the second position back to the first position, to: (ii) a second position in which the drive lock is disengaged to permit movement of the drive mechanism from the second position back to the first position.
17. The deployment applicator of claim 16, wherein the movement of the disengagement member from the first position to the second position comprises a rotation, for example wherein the disengagement member is configured to be rotated from the first position to the second position.
18. The deployment applicator of claim 17, wherein the disengagement member is biased towards being in at least one of the first and second positions. 30
19. The deployment applicator of any preceding claim, wherein the applicator comprises a retraction flange coupled to the drive mechanism and protruding from a side of the applicator, wherein the retraction flange is configured to be pulled to move the drive mechanism from the second position towards the first position in the event that the disengagement mechanism has disengaged the drive lock.
20. The deployment applicator of any preceding claim, wherein the applicator is arranged to limit distal movement of said porous medium relative to said catheter to a first threshold distance for each individual actuation of the deployment applicator.
21. The deployment applicator of any preceding claim, wherein the applicator is arranged to limit distal movement of said porous medium relative to said catheter to a second threshold distance for the cumulative distance provided by a plurality of actuations of the deployment applicator.
22. A vacuum therapy device for treatment of a defect internal of a human or animal body, the device comprising: a porous medium for treatment of the defect; a catheter having a proximal end and a distal end, wherein the catheter is configured to be inserted into the body to enable deployment of the porous medium through an opening at the distal end for treatment of the defect; and a deployment applicator configured to control distal movement of the porous medium relative to the catheter; wherein the deployment applicator is configured to: (i) selectively provide distal movement of the porous medium relative to the catheter, and (ii) inhibit proximal movement of the porous medium relative to the catheter.
23. The vacuum therapy device of claim 22, the deployment applicator comprises the deployment applicator of any of claims 1 to 21.
24. The vacuum therapy device of claim 23, wherein the movable element of the deployment applicator is connected to the porous medium via a tube which runs inside the catheter.
25. The vacuum therapy device of claim 24, wherein said tube within the catheter is also configured to provide suction at the porous medium.