GB2326344A

GB2326344A - Filling means for repairing an intestinal diverticulum

Info

Publication number: GB2326344A
Application number: GB9712707A
Authority: GB
Inventors: John Overton Hudson; Alberto Bauer
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-06-18
Filing date: 1997-06-18
Publication date: 1998-12-23
Also published as: GB9712707D0

Abstract

A filling means is inserted into a diverticulum in order to plug it and prevent ingress of faecal material. The filling means may comprise either; i) An inflatable balloon 2 with a shape memory alloy anchor 3; ii) a fibrous or curable filler material; iii) a resiliently deformable member, e.g. foamed plastic A catheter may be used to insert the filling means into the diverticulum.

Description

MEDICAL DEVICE AND USE THEREOF The present invention relates to materials, apparatus and methods for plugging a diverticulum.

Diverticula are sacral pockets or protrusions of variable size occurring normally through a defect in the muscular coating of a tubular organ, such as the intestinal tract.

Diverticula of the intestinal tract derive from the lumen and extend through the wall of the gut and are believed to be a contributory factor in colonic dysfunction. Typically, they may be enclosed by all layers of the bowel (serosa, muscle and mucosa), termed "true" diverticula; or they may lack muscle as a component of the sac, termed "false" or "pseudo" diverticula. True diverticula are usually congenital, while false diverticula are acquired, either by disease or secondary to pulsation forces in the gut, and typically are found at a site of an artery which feeds the bowel wall.

The diverticula of the colon are usually multiple and may be accompanied by inflammation. In the absence of inflammation condition is diverticulosis, while in the presence of inflammation the condition is known as diverticulitis. Although, the distinction between the two conditions is clear when a colon is examined surgically or histologically, the symptoms of colonic dysfunction due to diverticulosis sometimes mimic those of diverticulitis and, therefore, the clinical distinction between the two conditions may often be blurred. Consequently, diverticular disease of the colon typically refers to all stages of the disease from diverticulosis.

In diverticulosis the diverticula are initially microscopic in size but peristaltic contractions may cause them to enlarge slowly, until they become globular nodules projecting from the external surface of the bowel. These globular nodules are typically about one centimetre in diameter, though "giant diverticula" of over 3 centimetres in diameter are not unknown.

The globular diverticula communicate with the bowel lumen via a narrow neck through which gas can pass freely. They are prone to filling with faecal material extruded from the lumen that may then become firm. Such a process usually begins in the Sigmoid area and then typically spreads proximally throughout the intestinal tract over the course of several years.

Infection and inflammation of a diverticulum results in diverticulitis, and such inflammation patients with diverticulosis occurs in approximately 15 to 25 percent.

Complications associated with diverticular disease include sepsis, fistula, bleeding, obstruction and intractable painful disturbance of the bowel function, with typical septic complications being abscess and perforation of accompanied with diffuse bacterial and/or feculent peritonitis.

Although the true global prevalence of the disease is unknown, it has been estimated that in western countries the disease is uncommon before the age of 40 but approximately seventy percent of people may have the disease by the age of eighty five.

Accordingly, there is a need not only for a treatment of diverticular disease which prevents inflammation of diverticula, thereby arresting the progression of diverticulosis to diverticulitis, but also a treatment which prevents re-infection, ulceration, bleeding or perforation of previously inflamed diverticula that have been treated against infection.

The present invention seeks to provide materials, apparatus and methods for the treatment of diverticular disease.

According to a first aspect, the invention provides a device for plugging a diverticulum, comprising: filling means for insertion into the diverticulum, whereby the filling means is retained within the diverticulum.

The term "filling means" is intended to include any material and/or apparatus which can be inserted into, and substantially fill, a diverticulum to inhibit and preferably prevent, amongst other things, the ingress of deleterious substances such as faecal matter.

Preferably, the filling means comprises an inflatable balloon.

Conveniently, the balloon is made of an elastomeric material.

Preferably the balloon includes an inflation port provided with a nonreturn valve arrangement. Such an arrangement allows the balloon to be inflated irreversibly by entry of a filler material through the inflation port.

Advantageously, the outer surface of the balloon is textured or roughened to increase its surface area and, in use, promote tissue growth to encapsulate the balloon and thereby close the diverticulum.

To further promote the growth of fibrous tissue to close a diverticulum, a tissue growth promoting agent can be provided. For example the outer surface of the balloon may be coated with a growth promoting agent in the form of a bio-absorbable polymer such as polyglycolic acid. Other growth promoting agents including polysaccharides, poly lactic acid (PLA), poly lactide, cellulose ester, polycaprolactone, polyethylene glycol, polyphosphate ester, collagen, polydioxanone (PDS), trimethylene carbonate (TMC), hyaluronic acid (HA) and other glycosaminoglycans are within the knowledge of a skilled person.

Preferably the balloon is provided with anchor means to retain the filling means inside a diverticulum in use.

The term "anchor means" is intended to embrace any physical means by which filling means can be retained within a diverticulum, for example, an arrangement of one or more fingers, barbs or springs which can attach themselves onto the inner wall of the diverticulum and prevent the filling means from being expelled from the diverticulum by the peristaltic movement of the bowel.

Preferably, penetration of the inner wall of a diverticulum by an anchor is limited by one or more abutment means.

Preferably, the anchor is constructed from a shape memory alloy, a superelastic material or an elastic material, more preferably from nitinol, tempered steel, or a moulded plastic such as a thermosetting or thermoplastic plastic.

By "shape memory alloy" is meant an alloy which can be preformed into a first preferred shape while hot, cooled down and folded into a second shape, the second shape remaining fixed until the alloy is heated whereupon it returns to its first preferred shape.

Use of such alloys advantageously permit the anchor to be folded from a first preferred shape into a second shape which is small enough to fit into the end of a catheter. After insertion into a diverticulum the anchor returns to its first preferred shape due to the heat of the patients body.

By the term "superelastic material", we mean a material which has elastic properties such that a large change in strain is accompanied by a relatively small change in stress. That is, a material which has a modulus of elasticity (Young's modulus), close to zero.

The dimensions of the anchor will be selected so that in a retaining position the maximum dimensions of the anchor are greater than the maximum internal dimensions of a diverticulum i.e. from about 1 to 3 centimetres.

Preferably, the anchor further includes a flag that protrudes from the neck of a diverticulum after insertion of the anchor. This arrangement enables an Endoscopist to rapidly identify which diverticula have been filled, thereby increasing patient compliance.

Another preferred filling means comprises a curable material which can be used in non-solid form e.g. as a liquid, paste or gel form to fill a diverticulum and then cured into a hardened state.

The curable material should be bio-compatible and preferably quick-setting so that the procedure can be conducted rapidly. Suitable curable materials include silicone elastomers, polyurethane foam or elastomer, epoxy resins for example. Setting or curing of the material can be effected by solvent evaporation, ultra violet light or visible irradiation, or by heating.

The term "bio-compatible" is intended to mean being harmonious to life and not having toxic or injurious effects on biological function. This term is however, intended to embrace material which has a slightly irritant or thrombogenic effect in a host organism. Such an effect may be useful to promote tissue growth over a plugged diverticulum.

The curable material may be provided in two or more parts for mixing outside or within the diverticulum.

Preferably anchor means is inserted into a diverticulum with the curable material to retain the cured material within the diverticulum.

A further preferred filling means comprises a fibrous material such as a textile thread or fibre. Preferably the threads or fibres are coated with an adhesive material. The adhesive can be applied before, after, or at the same time as the fibrous material is inserted into a diverticulum.

Examples of suitable adhesives include Fibrin glues; non toxic thermosetting elastomeric adhesives such as moisture and UV light curing types and cyanoacrylates. Some examples may be found in the range of medically approved products distributed by Loctite UK Ltd.

Preferably, anchor means is provided to retain the fibrous material within the diverticulum.

Another preferred filling means comprises a resiliently deformable member, preferably an elastomeric member. In use, the elastomeric member is compressed, inserted into a diverticulum and released so that it expands to fill the diverticulum.

By "resiliently deformable member" we include the meaning of a member which can be deformed from a retaining shape in which it can be retained inside a diverticulum, to a smaller shape in which it can be inserted inside a diverticulum. The term resiliently is used to denote that the member can return to its retaining shape under suitable conditions.

Preferably, the deformable member is provided with anchor means constructed and arranged to retain the member within the diverticulum in use.

Preferably, diverticula which have been treated using materials and methods according to the invention are marked by suitable means to distinguish them from untreated diverticula. Suitable marking can be achieved in a variety of ways. For example, a marker "flag" can be provided in the form of an attachment to the filling means and/or anchor.

Preferably such a flag is formed of a biodegradable material such as cellulose alginate.

Alternately or additionally, a dye can be used as a marker. The dye can be applied as a spray, or as an injection i.e. a tattoo. The use of dyes is within the knowledge of a skilled person.

Preferred dyes include 5% methylene blue; Lugol's solution; toluidene blue; 1:4 solution of washable blue ink; 0. 1 S6 indigo carmine. A suitable tattoo medium could be an aliquot of sterile indian ink, diluted 1:100.

Preferably, the means for inserting the filling means into a diverticulum is a catheter.

Preferably, the catheter has a recess for receiving the filling means, a release mechanism for releasing the filling means from the catheter and, optionally injection means for injecting filler material into a diverticulum.

More preferably, the catheter comprises an inner and an outer tube, the inner tube slidably engaging the outer tube and having an injection means at a first end and a part for receiving the filler material at a second end.

The outer tube has an end portion outwardly extending from the first end of the inner tube defining the recess for receiving the filling means with the second end of the outer tube being joined to the inner tube by a seal.

The release mechanism, in use, reciprocates the outer tube relative to the inner tube. In this preferred arrangement the outer tube sits over the mouth of a diverticulum and acts as a restraining brace while the filling means is inserted into the diverticulum, filled with the filler material, and the injection means removed from the filler means. This prevents application of any undue force to the inside of the diverticulum being plugged, which increases patient compliance and further accelerates the encapsulation of the filling means with body tissue.

Preferably, the seal joining the outer tube to the inner tube has an inlet port for receiving a biocompatible fluid. This enables the Endoscopist to flush any body tissue from the recess restraining the filling means or to wash the inside of a diverticulum prior to insertion of the filling means.

Alternatively, the Endoscopist may pass a dye through the inlet port and spray mark the diverticulum which has been filled. This permits the Endoscopist to quickly identify which diverticula have been filled, thus increasing the efficiency of the overall process, with a concomitant decrease in expenditure and an increase in patient compliance.

In another aspect the invention provides a method for plugging a diverticulum comprising providing filling means as defined above and inserting the filling means into a diverticulum.

Preferred embodiments of the invention will now be described by way of non-limiting examples, with reference to the accompanying drawings in which: Figure 1 is a longitudinal cross-section of a preferred filling means of the invention comprising an inflatable balloon in an inflated condition and a preferred anchor means in its retaining position; Figure 2 is an end on plan view of the balloon of Figure 1; Figure 3 is a longitudinal cross-sectional view of the balloon of Figure 1 inflated inside a diverticulum; Figure 4 is a partial cross-sectional view of the balloon of Figure 1 mounted at the distal end of preferred delivery means in the form of a catheter; Figure 5 is a cross-sectional view of a preferred anchor of the balloon of Figure 1; Figure 6 is a plan view of the anchor of Figure 5; Figure 7 is a cross-sectional view of a preferred delivery means for delivering the balloon of Figure 1 to a diverticulum; Figures 8a and 8b are side and end views, respectively of a preferred anchor of the invention; and Figures 9a and 9b are partial cross-sectional side and end views, respectively of the anchor of Figures 8a and 8b mounted at the distal end of a catheter.

1. FiXing means: inflatable balloon There is shown in Figure 1 filling means (1) in the form of a balloon (2) in an inflated condition having preferred anchor (3) in a retaining position.

The balloon has an inflation port (4) and a non-return valve (5). The balloon is constructed from a preferred elastomeric material, a thin silicone polymer, by methods known to those skilled in the art, such as standard by dip moulding methods. The inflation port (4) and/or nonreturn valve (5) is preferably glued to the balloon, however other affixing methods are within the knowledge of a skilled person.

The outer surface of the balloon is textured or roughened to increase its effective surface area, thereby promoting tissue growth and encouraging complete encapsulation of the balloon in use. Preferably, the balloon is also coated with an abrasive material. Additionally, or alternatively, the balloon may be coated with an agent to promote further tissue growth and encourage rapid encapsulation. The growth promoting agent may be one or more of a number of bio-absorbable polymers, especially a polyglycolic acid (PGA), or one or more of poly lactic acid (PLA), poly lactide, cellulose ester, polycaprolactone, polyethylene glycol, polyphosphate ester, collagen, polydioxanone (PDS), trimethylene carbonate (TMC), hyaluronic acid (HA) and other glycosaminoglycans Preferably the balloon is inserted in the end of a catheter. This allows the balloon to be delivered into a diverticulum via the working channel of a conventional endoscope.

2. Anchor As shown in Figures 1, 5 and 6 the preferred anchor (3) has two arms (6a,6b) which, in the first retaining position shown, extend radially outwards from the balloon (2). As shown in Figures 5 and 6, the two arms (6a,6b) are of equal length and extend radially from diametrically opposed points of a central hub (7). The two arms (6a,6b) have barbs (8a,8b) at the ends furthermost from the central hub.

The anchor (3) may be connected to the inflation port (4), or more preferably, as shown in Figure 1, it is connected to the combined inflation port (4) and non-return valve (5). The anchor can be connected to the balloon by any known technique.

Preferably, the anchor (3) is constructed from the shape memory alloy nitinol. The anchor can be folded from a first retaining position (shown in Figure 3 for example) into a second deformed condition in which it is small enough to allow the balloon to be inserted into a suitable delivery device, as shown in Figure 4.

Furthermore, an anchor constructed of nitinol can easily be formed on a jig from a piece of nitinol wire, filled by a simple heat treatment in a muffle furnace for example, so that the nitinol is set into its first retaining position.

Alternative methods of making the anchor include standard techniques known to those skilled in the art, for example a stamping from sheet material, from a tube or a combination of these methods.

An alternative preferred anchor arrangement (16) is shown in Figures 8a and 8b. The anchor is made from nitinol wire and or nitinol tubing.

Figures 9a and 9b show the anchor (16) mounted inside the distal end of a preferred catheter having an anchor ejector tube (17) and a central lumen (18) for spraying or injecting a marker dye.

Preferably, the anchor has a flag (not shown) attached thereto which protrudes from the neck of a diverticulum after the anchor has been implanted. More preferably, the flag is constructed from either a water soluble or biodegradable polymer so that it is quickly absorbed after the procedure. In a particularly preferred arrangement the flag is made of cellulose alginate.

3. Delivery means As shown in Figures 4 and 7, a preferred delivery means for inserting the balloon into a diverticulum and means for inflating by filling the balloon with a filler material is a catheter (10). The catheter has a recess (11) for receiving the balloon, a release mechanism (12) for releasing the balloon from the catheter and an injection means (15) for filling and inflating with a filler material. As shown in Figures 4 and 7, the catheter comprises a continuous double tube having an inner tube (12a) that is slidably engaged with an outer tube (13).

The distal end of the outer tube has an end portion (14) that extends outwardly from the distal end of the inner tube, thereby defining the recess (11) to receive and constrain the balloon and anchor prior to insertion into a diverticulum. The proximal end of the outer tube is connected to the inner tube by a seal, preferably by a seal having an inlet port to receive a bio-compatible fluid such as water into the space between the inner and outer tubes. Preferably, the seal is a "Touhy-Borst" connector. Preferably, the bio-compatible fluid is water for flushing the recess and thereby removing any body tissue or for washing the inside of a diverticulum prior to insertion of the balloon. Alternatively, or additionally, the fluid may be a dye for marking a diverticulum that has received a balloon.

Preferably, the length of the continuous double tube is greater than 2.25 metres. Preferably the outer tube has an outside diameter of between 7 and 12 French (2.5amp), so that it is able to fit inside the working channel of a conventional endoscope.

The distal end of the inner tube terminates in an injection means (15) for filling the balloon with a filler material which is preferably a biocompatible fluid such as water.

The injection means (15) may be permanently sealed to the distal end of the inner tube using standard methods, or be removably sealed to the distal end of the inner tube using standard methods, for example a screw thread type connection. Preferably, the injection means is a nozzle, a tubular member or an injection needle. The proximal end of the inner tube is terminated with a standard luer pressure tight connector, having a stopcock for receiving a pressure controlled inflation device having a monitor for both volume and pressure.

At the proximal end of the continuous double tube catheter is the release mechanism (not shown), that moves the inner tube within the outer tube by an amount not less than the length of the inflation device that is mounted at the distal end of the inner tube and constrained by the outer tube.

4. Preferred method of plugging a diverticulum The complete procedure is carried out endoscopically. A preliminary examination is usually carried out to determine the extent of the disease, preferably by a combination of barium x-ray and colonoscopy. The number and approximate position of the diverticula to be filled will therefore usually be known. Patient preparation is the same as for normal colonoscopy, preferably the endoscope is inserted and the colon inflated.

Preferably, the balloon is mounted onto the injection means (15) of the delivery catheter, as shown in Figures 4 and 7. The anchor is folded, preferably longitudinally along the balloon, and the injection means sealed on the distal end of the inner tube with the outer tube constraining the balloon and anchor within the recess, as shown in Figures 4 and 7.

Alternatively, the anchor is folded, preferably longitudinally along the balloon, and the balloon is mounted on the injection means that is permanently sealed to the distal end of the inner tube; with the outer tube constraining the balloon and anchor within the recess.

The distal end of the double walled catheter is threaded through the working channel of a standard endoscope, the endoscope inserted, the colon inflated, and the balloon delivered to the mouth of a diverticulum using the controllable tip of the endoscope.

Prior to inserting the balloon, it may be necessary to wash the inside of the diverticulum. This can be carried out by placing the distal end of the outer tube over the mouth of the diverticulum, and passing a biocompatible fluid, such as water, through the inlet port on the "Touhy Borst" type seal.

The distal end of the outer tube is presented to the mouth of the diverticulum and the balloon is pushed into the diverticulum by advancing the inner tube.

After the balloon has been completely inserted into the diverticulum, a pressure controlled inflation device is used to inflate the balloon to a specific volume and/or pressure with filler material, so that the balloon completely fills the diverticulum, as shown in Figure 3. The required volume/pressure for inflation of the balloon can be determined by routine trial and error testing by a skilled person.

The inner tube is then withdrawn to remove the injection means from the inlet port of the balloon and the non-return valve prevents the filler from escaping from the balloon. The advantage of withdrawing the inner tube prior to withdrawing the outer tube is that the outer tube acts as a restraining brace, thereby preventing any undue force inside the diverticulum.

When the filling means (1) e.g. a balloon (2) and anchor is inserted into a diverticulum (9) and is inflated, the anchor returns to its retaining position in which the barbs (8a,8b) engage the inner wall (9a) of a diverticulum to prevent the filling means from being expelled from the diverticulum by the peristaltic movement of the bowel because they grip the inner wall of the diverticulum, as shown in Figure 3.

As shown in Figure 3, the barbs of the anchor are arranged so that their penetration of a diverticulum inner wall is limited to the distance X.

Herein, such arrangement to limit penetration is termed abutment means" .

Preferably, the filled diverticulum is marked by passing a dye spray down through the inlet port of the "Touhy-Borst" seal.

5. Alternative preferred jwing means (i) Curable filler material Curable filler material is provided as a non-solid form e.g. liquid, gel, or paste and will cure or set to a solid form after insertion into a diverticulum. Preferably the material sets very quickly, so that the diverticula plugging procedure can proceed quickly.

Non-exhaustive examples of curable material include silicone elastomers, polyurethane foams and elastomers, epoxy resins etc.

Skilled person will appreciate that curable materials can be provided in the form of two or more discrete substances which cure on mixing.

Curing may be effected by a variety of means including solvent evaporation, UV or visible light irradiation or heating. Preferably the curable material which cures at human body temperature.

(ii) Fibrous filler material Fibrous filler material such as textile fibres or threads can be used to fill a diverticulum. Preferably the fibre or thread is coated with an adhesive material before or after insertion into a diverticulum.

(iii) Resiliently deformable member Filling means in the form of a resiliently deformable member represent another preferred embodiment of the invention.

In use, the member is deformed from a retaining position into a second smaller position and inserted into a diverticulum. Once inside the diverticulum the deformable member returns to its retaining position so that it is retained with the diverticulum.

Preferably, the deformable member is an elastomeric member e.g. foamed plastic such as foamed silicone or foamed polyurethane which can be compressed and inserted into a diverticulum. When the compression force is released the member expands into its uncompressed retaining position and thereby fills the diverticulum.

The deformable member may also comprise a member formed from a shape memory alloy such as nitinol, which can be folded for insertion and expand to a predetermined retaining position in response to a patient's body heat, for example.

It will be appreciated that it may be necessary to use different delivery means depending on the filling means used according to the invention.

If filling means (i) or (ii) are used in combination with anchor means, the delivery means will comprise a two-part system, one for delivering the anchor and the other for delivering the filler material. A plurality of anchors can be mounted in a magazine at the distal end of the catheter.

The catheter allows the anchors to be fed one at a time into a delivery nozzle at the distal end. The delivery nozzle can be withdrawn to release the anchor, after the distal end of the catheter is placed into the neck of the diverticulum. In this way a number of anchors may be inserted into multiple diverticula without the need to withdraw the catheter from the endoscope after each insertion.

The filler is injected into the diverticula using an injection catheter and syringe.

The catheter is multi-lumen when using a two-part mix curable material.

The two lumen come together at the distal end of the catheter and terminate into a single nozzle where the contents of each lumen are mixed.

At the proximal the material is injected via a two lumen syringe.

According to the type of filler used, curing can be carried out via another lumen of the injection catheter, or by a separate catheter. For example a fibre optic carrying UV or visible light could be delivered via a separate lumen.

Delivery catheter anchor A separate anchor delivery catheter may consist of a tube and a central rod. A number of folded anchors can be loaded into the distal end of the outer tube.

At the proximal end of the catheter is a mechanism which can withdraw the outer tube over the central rod by an indexed amount equal to the length of one folded anchor.

The distal end of the catheter is inserted into the neck of the diverticula and then the outer tube is withdrawn by an indexed amount. This will release one anchor into the diverticulum, allowing it to expand to its full size. Preferably, a flag is attached to the proximal end of the folded anchor, and is folded behind it. Thus, the flag will protrude from the neck of the diverticulum in use.

Delivery Catheter Filler The design of the filler catheter varies according to the material type of the filler. In its simplest form it is a single lumen tube with an injection nozzle at the distal end. The filler material is injected into the diverticulum by an indexing pump at the proximal end of the catheter.

If the filler material is a two part resin, then a two lumen catheter is used with a mixer nozzle at the distal end.

Other preferred methods: using a separate anchor and non-solid curable and/or fibrous filler materials The first part of the procedure is to insert the anchors. The loaded insertion catheter is first introduced into the colon via the working lumen of the endoscope. These are inserted into the diverticula from an anchor magazine insertion arrangement on the distal end of the insertion catheter.

Soluble or biodegradable flags may be left protruding from the diverticula neck to show which have had an anchor inserted.

When all the anchors have been inserted the anchor insertion catheter is withdrawn from the endoscope.

As an alternative to the flag, a central lumen of the anchor insertion catheter may be used to spray a dye around the neck of the filled diverticula. To prevent the dye leaking proximally, the proximal end of the outer tube is terminated in a seal of the Touhy-Borst type.

The filler catheter is now introduced into the colon via the endoscope lumen. Using the flags (or dye spray), as a guide, each diverticula is injected with the filler material, so that it is completely full. The material will be in the form of a gel, or a past or a glue coated textile fibre, so that, it will not be expelled before it is cured, due to the peristaltic action of the colon.

If the material is self curing, then all that remains is to leave the colon inflated until the material is set. If the material requires an additional curing means, then this is now applied.

Claims

1. A device for plugging a diverticulum comprising filling means for insertion into the diverticulum, whereby the filling means is retained therein.

2. A device as claimed in Claim 1 wherein the filling means comprises an inflatable balloon.

3. A device as claimed in Claim 1 wherein the filling means comprises a non-solid curable material which can be used to fill a diverticulum and then be cured into a hardened state.

4. A device as claimed in Claim 1 wherein the filling means comprises a fibrous material.

5. A device as claimed in Claim 1 wherein the filling means comprises a resiliently deformable.

6. A device as claimed in Claim 5 wherein the resiliently deformable member is an elastomeric member.

7. A device as claimed in any one of Claims 1 to 6 wherein the filling means includes anchor means for retaining the filling means within the diverticulum.

8. A device as claimed in Claim 7 wherein the anchor means comprises one or more arms arranged to engage the inner wall of a diverticulum in use, so that the filling means is retained therein.

9. A device as claimed in Claim 8 wherein the arms of the anchor means are resiliently biased apart.

10. A device as claimed in Claim 8 or 9 wherein the, or one or more, arm includes a barb.

11. A device as claimed in Claim 10 wherein penetration of the inner wall of the diverticulum by the barb is limited by an abutment means.

12. A device as claimed in any one of Claims 7 to 11 wherein the anchor means is made from a shape memory material.

13. A device as claimed in Claim 12 wherein the anchor is made from nitinol.

14. A device as claimed in any one of the preceding claims wherein the filling means is adapted to promote growth of fibrous tissue in use.

15. A device as claimed in Claim 14 wherein the filling means is provided in combination with a growth promoting agent, preferably polyglycolic acid.

16. A device as claimed in any one of the preceding claims wherein marker means is provided for indicating a diverticulum which has been plugged.

17. A device as claimed in Claim 16 wherein the marker means comprises a flag constructed and arranged to protrude from a filled diverticulum in use.

18. A device as claimed in Claim 16 or Claim 17 wherein the marker means is biodegradable, and preferably comprises cellulose alginate.

19. A device as claimed in Claim 2 or any claim dependent on Claim 2 wherein the balloon includes an inflation port fitted with a non-return valve.

20. A device as claimed in Claim 2 or any claim dependent on Claim 2 wherein the outer surface of the balloon is adapted to promote growth of fibrous tissue in use.

21. A device as claimed in Claim 20 wherein the outer surface of the balloon is roughened or textured.

22. A device as claimed in Claim 20 wherein the outer surface of the balloon is coated with an agent to promote growth of fibrous tissue.

23. Apparatus for plugging a diverticulum comprising a device as claimed in any one of Claims 1 to 22 and delivery means for inserting the device into a diverticulum.

24. Apparatus as claimed in Claim 22 wherein the delivery means comprises a catheter adapted to hold one or more devices as claimed in any one of Claims 1 to 22.

25. Apparatus as claimed in Claim 23 or Claim 24 wherein the delivery means is provided with means for applying marker means to indicate a filled diverticulum.

26. Apparatus as claimed in Claim 25 wherein the marker means is a dye.

27. Use of a device as claimed in any one of Claims 1 to 22 in the manufacture of apparatus for the treatment of diverticular disease.

28. A method of plugging a diverticulum comprising the steps of: providing filling means as claimed in any one of Claims 1 to 22; and inserting the filling means into a diverticulum, so that the filling means is retained therein.

29. A method as claimed in Claim 28 comprising the further step of applying marker means to indicate that the diverticulum has been plugged.

30. A device for plugging a diverticulum substantially as described herein, and preferably with reference to one or more of the accompanying drawings.

31. Apparatus for plugging a diverticulum substantially as described herein, and preferably with reference to one or more of the accompanying drawings.

32. A method of plugging a diverticulum substantially as described herein, and preferably with reference to one or more of the accompanying drawings.