GB2355937A

GB2355937A - Urinary sphincter device

Info

Publication number: GB2355937A
Application number: GB0022812A
Authority: GB
Inventors: Joseph Shannon Gallagher
Original assignee: Biosil Ltd
Current assignee: Biosil Ltd
Priority date: 1999-09-16
Filing date: 2000-09-18
Publication date: 2001-05-09
Anticipated expiration: 2020-09-18
Also published as: GB0022812D0; GB2355937B; GB9921788D0

Abstract

An implantable sphincter device 1 suitable for use in occluding a body passage (4; Fig 5). The device comprises an inflatable, flexible cuff 2 adapted to be position around a body passage (4). The cuff 2 is formed and arranged when inflated with fluid 6 to close around and shut the body passage (4; Fig 5) and when deflated to open the body passage. A pump 10 for inflating and deflating the cuff is provided together with a fluid reservoir 12. The fluid reservoir 12 and pump 10 are in the form of a single discrete unit in remote fluid communication with the cuff via a single fluid transmission line 8. In use with the cuff portion 2 implanted around a body passage (4; Fig 5) and with the single discrete unit 10 implanted remotely from the cuff 2 in, for example, the scrotum or labium, a user may control the opening and closing of the cuff 2 and thereby a body passage to facilitate voiding. An improved C-shaped cuff arrangement is described also.

Description

2355937 URINARY SPHINCTER DEVICE The present invention relates to a device

for occluding a body passage. In particular the present invention relates to a device for controlling the flow of bodily fluids through a body passage such as the urinary track in much the same way as a sphincter.

Incontinence is a major medical problem that affects millions of people of all ages world wide. Incontinence is the inability to voluntarily control the discharge of bodily materials. The condition may be caused by physical, neurological or physiological traumas. The condition can be particularly distressing for sufferers including forcing those affected to withdraw from or to be unable to participate in regular social activities.

The use of an artificial sphincter to overcome incontinence was originated by Foley in 1947 who used such an artificial sphincter to treat urinary incontinence. The Foley artificial urinary sphincter was simple in design and operation and depended on an inflatable cuff wrapped around the penile urethra and controlled by an air pump carried in the patients trouser pocket. More recently totally implantable artificial urinary sphincter (AUS) devices have been adopted. Such AUS devices generally comprise three separate parts:an inflatable cuff configured to surround and occlude the body passage, a pump and a bulb type reservoir. There are two -2types of reservoir bulbs available - a non-expandable pressure variable bulb and an expandable constant pressure type bulb. The three basic components are connected by fluid transmission lines. One conduit or fluid transmission line connects the cuff with the pump. A second conduit or fluid transmission line connects the pump with the reservoir bulb.

To operate such an AUS device the cuff is inflated to occlude the body passage and deflated to allow the discharge of fluid through the body passage. The cuff is generally maintained in a normally inflated (closed) position. Such devices are generally well known and an example is disclosed in US Patent No. 4222377 to Burton. This device has undergone a number of modifications which has resulted in a simple design model which has been successfully exploited by American Medical Systems, Inc. of the USA to control urinary incontinence and is known as the model AMS Sphincter 800.

A study on such AMS AUS devices implanted into both men and women concluded that they provide a "successful method of treatment for sphincter weakness incontinence regardless of aetiology" (Mundy & Nurse, 1988. One Hundred Artificial Sphincters. Brit Journal of Urol, 61,3183258). In this study the conclusion is prefaced with a list of problems which are intrinsic to the AMS Sphincter 800, namely that the pressure control can not be altered without further surgery to replace the fixed pressure balloon; the device cannot rapidly increase cuff pressure in response to surges in abdominal -3pressure as would be necessary to prevent distress incontinence which is stated as being a particular problem when the cuff is placed in the bulbar urethra position and the pump, for deflating the cuff is not easy to use, and some women find it distasteful to manipulate their labium in order to void, particularly if they get their hands wet in the process. Moreover information extracted from the US Governments FDA database reports a global complication rate for such devices of approximately 25%. 10 Moreover there are further problems associated with known present systems. For instance the components of presently available devices, i.e. the cuff, the pump and the bulb are implanted separately into different areas of the body and are connected together by fluid transmission lines. European Patent No. 348114 (American Medical Systems, Inc.) has recognised that it would be desirable to remove the need to implant separately the various components of such devices. This is because of the presence of any implant in the body can cause irritation to the surrounding body tissues. Increasing the number of components separately implanted will affect more tissue. Moreover body tissue must adapt to the implanted components before the sphincter can be activated as the body may reject the implant, or worse, there may be infection.

Accordingly it is usually necessary to wait some four to six weeks after such devices have been implanted before they may be activated.

-4In some cases, even though the surrounding tissue is allowed to adapt to the presence of the implant, the expansion and contraction of the constant pressure reservoir bulb can cause erosion and scarring of body tissue. Consequently it is known to be desirable to reduce the number and size of the components of such AUS devices that are implanted. European Patent No. 348114 seeks to address the problems and trauma caused by separately implanted reservoir bulbs by providing a fluid actuated artificial sphincter having an inflatable cuff 10 in direct contact with a body passage and a hollow resilient C-shaped reservoir ring that surrounds the cuff and a pump for inflating the CUff. Although this device obviates one of the problems of such sphincter devices by reducing the number of components from three to two the combined inflatable cuff and hollow resilient C-shaped reservoir ring that surrounds the cuff is of a larger size than a conventional cuff, and as such, such devices are unsuitable for implantation into anatomically small patients and in particular children. Moreover the increased size of such a combined cuff and reservoir and the consequent expansion and contraction of the reservoir and cuff can give rise to further erosion and scarring of body tissue. Yet a further disadvantage of EP348114 is that there is required two fluid transmission lines connecting the cuff with the pump and the pump with the reservoir bulb surrounding the cuff. For surgical implantation reasons it is desirable to reduce as much as possible the number of items to be surgically implanted into a body and to prevent the accidental or incorrect connection of -5such fluid transmission lines. The incorrect connection of such fluid transmission lines would necessitate further corrective surgery and thus trauma to the patient.

Yet a further problem associated with known AUS devices relates to the shape and configuration of the cuff portion. The cuff supplied with the AMS sphincter 800 device is in the form of a generally flat cuff having a generally non-elastic backing with a flexible expanding skin on its other side.

This flat cuff is then wrapped around the body passage to be occluded and held in place by a strap. A particular problem with this arrangement is that when the flat cuff is arranged in a C-shape around the body passage, the tissue of the body passage to be occluded can become trapped in the creases that are formed in the folding of the cuff. Moreover as the cuff is inflated and deflated body tissue can be continually trapped and released in the creases and is therefore prone to rupture or necrosis.

It is an object of the present invention to avoid or minimise one or more of the aforementioned disadvantages and problems associated with existing devices.

According to the present invention there is provided an implantable sphincter device suitable for use in occluding the urethra, the bladder neck or other body passage, which device comprises: an inflatable, flexible cuff portion adapted to be positioned around a said body passage, said cuff being formed -6and arranged when inflated with fluid to close around and shut a said body passage and when deflated to open the body passage; means for inflating and deflating said cuff portion; and a fluid reservoir; said fluid reservoir and said means for inflating and deflating said cuff being in the form of a single discrete unit in remote fluid communication with said cuff via a single fluid transmission line, whereby in use with said cuff portion implanted around a said body passage and with said single discrete unit comprising said fluid reservoir and said means for inflating and deflating said cuff implanted remotely from said cuff, in, for example, the scrotum or labium, a user may control the opening and closing of the cuff and thereby a said body passage to facilitate voiding.

Thus with the implantable sphincter device according to the present invention it is possible to implant both components of the device in a more simple and convenient manner than previously possible thereby reducing the time required to surgically implant the device. Moreover less tissue is effected because the cuff portion is much smaller than previously known designs of combined cuff and the reservoir. Additionally the means for inflating and deflating of said cuff, is not implanted into a separate area of tissue.

Preferably said means for inflating and deflating said cuff is in the form of a pump means. A suitable pump means would be one similar to that used with the AMS Sphincter 800 device with one important difference, that being that there is only a -7single fluid.transmission line between the pump means and the cuff. Preferably said pump means is an implantable device manufactured from physiologically acceptable materials such as silicone rubber or a solid silicone elastomer.

Preferably said pump means including said fluid reservoir has a first passage means allowing fluid communication between said fluid reservoir and a body portion of said pump means and a second passage means allowing fluid communication with said single fluid transmission line and said fluid reservoir and said body portion, said body portion housing a valve means, preferably a bistable valve means, formed and arranged to permit fluid to flow through one or other of said first and second passage means into fluid communication with a third passage means connected an outlet portion of said pump means so as to facilitate inflation or deflation of the cuff.

Preferably said body portion of said pump means surrounding said reservoir defines said reservoir and is of a more or less resilient material containing fluid so as to facilitate squeezing thereof by a patient in use of the device so as to pressurise fluid in said reservoir and thereby to force it from said reservoir through said first passage means into said fluid transmission line and into said cuff so as to inflate said cuff with pressurised fluid. The outlet portion of the reservoir into the pump body houses a non-return valve to prevent pressurised fluid in the cuff leaking back into the -8reservoir and thus there is created a partial vacuum in the now flattened reservoir portion of the pump means.

Preferably said bistable valve means is formed and arranged to be driven from a closed position to an open position by a person in use of the pump physically pressing on an end portion of the valve. The said end portion of said valve, preferably a poppet type valve, preferably extends above the main body portion of the pump so as to facilitate a user of the pump to locate and to press on said end portion of said valve so as to drive it into said open position so as to allow fluid in said cuff to travel along said single fluid transmission line into the fluid reservoir. Deflation of the cuff allows the body passage occluded by it to open to facilitate voiding.

To occlude the passage, upon completion of voiding, a patient in use of the device squeezes the fluid reservoir thereby pumping fluid contained therein through the body of the pump means, through the single fluid transmission line and into the cuff so as to inflate it and thereby occlude the body passage surrounded by said cuff.

Preferably said single fluid transmission line is in the form of a length of tubing for example silicone elastomer tubing which is resistant to kinking or flattening. The said single fluid transmission line may be bonded or otherwise connected to said cuff and said pump means though preferably and for -9ease of implantation surgically, said single fluid transmission line is in two parts having a first length attached or bonded to said pump means and a second portion bonded or attached to said cuff portion and there being provided means for connecting said first and second portions of said fluid transmission line together.

Preferably said flexible cuff portion is generally C-shaped and comprises a generally C-shaped non-elastic backing or outer surface and a corresponding generally C-shaped inner elastic membrane which inflates upon action of pressurised fluid entering said cuff portion to a generally C-shaped form wherein the radius of curvature of the inner elastic membrane is reduced but is substantially parallel to the radius of curvature of the membrane in a deflated condition.

As the cuff portion of the sphincter device according to the present invention is substantially smaller than the combined cuff and reservoir bulb disclosed in European Patent No.

3481114, it reduces the chance and amount of damage to tissue surrounding the cuff and makes the surgical implantation and thus time required to surgically implant such a device to be reduced.

Preferably said cuff portion is in the form of a one piece silicone rubber cuff manufactured using a dipped or moulded shell. This method of forming the cuff minimises any creases which may develop in the inner elastic surface of the C-shaped _10cuff as it is inflated around the urethra or bladder neck or other body passage.

Desirably said pump means is provided with a "block out" valve formed and arranged to maintain the cuff portion in an open condition during the healing process required after implantation of the sphincter device according to the present invention.

In another respect the present invention provides a flexible cuff for occluding a body passage and suitable for use with an AUS device including a device according to the invention wherein said flexible cuff is generally C-shaped and comprises a generally C-shaped non-elastic backing or outer surface and a corresponding generally C-shaped inner elastic membrane formed and arranged to be inflated upon actuation of pressurised fluid entering said cuff portion to a generally Cshaped form wherein the radius of curvature of the inner elastic membrane is reduced but is substantially parallel to the radius of curvature of the membrane in a deflated condition and substantially parallel to said generally Cshaped non-elastic backing.

Preferably the device and the cuff are made available in a variety of different sizes so as to be suitable for use on a range of patients of different anatomical size. Preferably the cuff portion is provided in a range of sizes ranging from 2 cm to 12 cm in radius. Preferably where the cuff is of a larger size it will be appreciated that a larger volume of fluid is required and thus the reservoir of the device will have a corresponding larger volume.

Preferably it is desirable to provide devices which are available with variable cuff pressure (reservoir) and these are provided in the range of from 51 to 60 cm H20 through to 81 to 90 cm H20, desirably 71 to 80 cm H20.

Further preferred features and advantages of the present invention will appear from the following details description given by way of example of a preferred embodiment illustrated with reference to the accompanying drawings in which Figure 1 is a schematic view of the components of an implantable sphincter device according to the invention; Figure 2 is a sectional plan view through a preferred embodiment of a pump means for use with a implantable sphincter device according to the invention; Figure 3 shows a side view of the C-shaped cuff portion of the sphincter device in an inflated occluded condition; and Figure 4 is similar to Figure 3 and shows the cuff portion in a deflated open condition; and Figure 5 shows the sphincter device implanted in place in a male patient. 25 An implantable sphincter device, generally indicated by reference no. I is shown in Figures 1 and 5. The device is -12implanted into a patient in such a way that the patient may use the device to control their urinary requirements.

The device 1 comprises an inflatable, flexible cuff 2 adapted to be positioned around the urethra 4 (see Fig 5 also) in fluid 6 communication via a connected 7 single fluid. transmission line 8 with a pump 10. The cuff 2 is arranged when inflated with fluid to close around and shut the urethra 4 (Fig 3) and when deflated to open the urethra 4 (Fig 4).

The pump 10 includes a fluid reservoir 12 and is in the form of a single discrete unit 10 formed and arranged to be surgically implanted into a patient, for example on a male patient into the scrotum 14 (See Fig 5), in such a way that the patient may use the pump to inflate and deflate the cuff 2 so as to allow the patient to control their urinary requirements. Alternatively the pump could be placed in any other suitable position in the body for example above the hip area. As the pump is implantable it requires to be relatively small and compact and thus the pump 10 described typically has dimensions of 22mm depth 32mm width and 60mm in overall length.

The construction and mode of operation of the pump will be described further with reference to Figures 2 to 4.

The pump 10 comprises a housing 16 surrounding a body 18 which defines a plurality of fluid passages 20 which will be described in more detail below. The pump 10 is used to pump -13fluid between the fluid reservoir 12 of the pump 10 and the cuff portion 2 of the sphincter device I so as to close the cuff portion 2 upon completion of voiding. The pump 10 is provided also with means to open the cuff portion to facilitate voiding.

In more detail the pump 10 comprises a pump reservoir 12 or bulb defined by a portion 16a of the housing 16; a cuff fluid passage 20a for fluid communication between the pump body 18 and the cuff 2 of the artificial sphincter device; a reservoir return fluid passage 20b for fluid communication through the body 18 into the reservoir or bulb 12 from the cuff and a shunt fluid passage 20c for diverting fluid communication between either the cuff fluid passage 20a and the reservoir return fluid passage 20b. A poppet valve 22 is provided in the shunt fluid passage 20c for controlling fluid communication between the cuff 20a and reservoir return 20b fluid passages.

The poppet valve 22 works as a bistable valve with three ports. The poppet valve 22 is essentially a bistable valve which can be moved between a first open position (Fig 4) and a second closed position (Fig 3). A chamber 24 in the body 18 of the pump 10 in which the poppet valve is located has a reduced diameter waist portion so that the valve stays in the open or closed position as required. As the pump body 18 is made from silicone rubber which is more or less resilient the waist portion is resiliently deformed so the poppet valve -14passes between the open and closed portions. When the poppet valve is in an "up" position as shown in Fig 3 so as to close the shunt fluid passage 20, fluid contained within the reservoir or bulb 12 when squeezed, for example, between the 5 thumb and forefinger (shown schematically by arrows X and Y) of a person in use of the device is pressurised and forced along the cuff passage 20a (shown by direction arrow "A" in Fig 2) through the fluid transmission line 8 into the cuff 2. The pressure of the fluid acting on the underside of the poppet valve 22 causes it to be driven into the "up" position as shown in Fig 3. Fluid is restricted from returning to the pump bulb reservoir by a conical shoulder on the poppet valve mating with the female seat of the inner block of the sealing port.

It will be noted that when the cuff is inflated occluding the body passage, as it will be most of the time, the size of the pump is significantly reduced as the reservoir contains little or no fluid.

To empty and deflate the cuff as shown in Fig 4 the poppet valve is pressed by a user so as to push it into a "down" position such that the pressurised fluid in the cuff passes back along the fluid transmission line 8 into the pump body 18 around the poppet valve 22 and through the reservoir fluid passage 20b (shown by direction arrow "B"). A spring 28 biased ball 30 check valve 26 in the cuff fluid passage 20a prevents fluid 6 flowing back into the cuff. The reservoir -15return fluid passage 20b is provided also with a check valve 31 to prevent fluid being pumped from the reservoir 12 into the reservoir return fluid passage 20b.

As will be seen the poppet valve 22 has an extended shaft portion which stands proud from the pump body 18 but which is covered by a nipple portion 32 on the outer casing 34 of the pump 10. This nipple portion 32 immediately above the poppet valve 22 serves to enable a user of the pump, which is of course implanted under the skin, to locate the poppet valve 22 so as to manually press the valve into a closed position (Fig 4) to facilitate voiding by deflation of the cuff.

Turning now to Figures 3 and 4 which shows in more detail the cuff 2. The cuff 2 is inflatable having a generally nonelastic more or less backing 34 with a flexible inner expanding membrane 36. The cuff 2 is held in a normally inflated position with pressurised fluid 6 contained between the generally non-elastic backing 34 and the flexible inner expanding membrane 36 which is in direct contact with the body passage 4 being occluded. When in an deflated condition, to facilitate voiding, as shown in Figure 4 the flexible inner expanding membrane 36 is generally substantially parallel to the non-elastic or rigid backing 34. When fluid enters between the non-elastic backing 34 and the flexible membrane 36 the membrane 36 tends to expand in a generally annular way and without any creases developing as the flexible membrane 36 expands into occluding contact with the body passage 4. This -16is because the non-elastic backing prevents the flexible membrane from attempting to straighten out and prevents portions of the membrane overlapping on itself and possibly catching body tissue. Thus the problems associated with conventional cuffs, such as the AMS 800 sphincter cuff, are obviated.

Example Tests undertaken with prototype samples have proved the basic function and operating principles of the design. Satisfactory inflation and deflation has been achieved. Inflation of the cuff over a period of 48 hours has been achieved whilst maintaining continence.

Various modification may be made to the above described embodiment without departing from the scope of the present invention. Thus for example other biologically acceptable materials may be used in the construction of the pump, the fluid transmission line and the cuff. Furthermore the ball valves may be replaced with other suitable valves for examples flapper valves.

Claims

-17CLAIMS

1. An implantable sphincter device suitable for use in occluding the urethra, the bladder neck or other body passage, which device comprises: an inflatable, flexible cuff portion adapted to be positioned around a said body passage, said cuff being formed and arranged when inflated with fluid to close around and shut a said body passage and when deflated to open the body passage; means for inflating and deflating said cuff portion; and a fluid reservoir; said fluid reservoir and said means for inflating and deflating said cuff being in the form of a single discrete unit in remote fluid communication with said cuff via a single fluid transmission line, whereby in use with said cuff portion implanted around a said body passage and with said single discrete unit comprising said fluid reservoir and said means for inflating and deflating said cuff implanted remotely from said cuff, in, for example, the scrotum or labium, a user may control the opening and closing of the cuff and thereby a said body passage to facilitate voiding.

2. A device as claimed in claim I wherein said means for inflating and deflating said cuff is in the form of a pump means.

3. A device as claimed in claim 2 wherein said pump is formed and arranged to be actuatable by the patient in use of the -18device to move fluid between the reservoir and the cuff portion.

4. A device as claimed in claim 2 or claim 3 wherein said pump means is an implantable device manufactured from physiologically acceptable materials selected from the group including silicone rubber or a solid silicone elastomer.

5. A device as claimed in anyone of claim 2 to 4 wherein said pump means including said fluid reservoir has a first passage means allowing fluid communication between said fluid reservoir and a body portion of said pump means and a second passage means allowing fluid communication with said single fluid transmission line and said fluid reservoir and said body portion, said body portion housing a valve means, formed and arranged to permit fluid to flow through one or other of said first and second passage means into fluid communication with a third passage means connected an outlet portion of said pump means so as to facilitate inflation or deflation of the cuff.

6. A device as claimed in claim 5 wherein said valve means is a bistable valve means.

7. A device as claimed in claim 5 or claim 6 wherein said body portion of said pump means surrounding said reservoir defines said reservoir and is formed from a more or less resilient material containing fluid so as to facilitate squeezing thereof by a patient in use of the device so as to _19pressurise fluid in said reservoir and thereby to force it from said reservoir through said first passage means into said fluid transmission line and into said cuff so as to inflate said cuff with pressurised fluid. 5

8. A device as claimed in anyone of claims 5 to 7 wherein the outlet portion of the reservoir into the pump body houses a non-return valve to prevent pressurised fluid in the cuff leaking back into the reservoir.

9. A device as claimed in any one of claims 6 to 8 wherein said bistable valve means is formed and arranged to be driven from a closed position to an open position by a person, in use of the pump, physically pressing on an end portion of the valve.

10. A device as claimed in claim 9 wherein the said end portion of said valve, extends above the main body portion of the pump so as to facilitate a user of the pump to locate and to press on said end portion of said valve so as to drive it into said open position so as to allow fluid in said cuff to travel along said single fluid transmission line into the fluid reservoir whereby deflation of the cuff allows the body passage occluded by it to open to facilitate voiding.

11. A device as claimed in any one of claims 6 to 10 wherein said valve is a poppet type valve.

-2012. A device as claimed in anyone of claims 1 to 11 wherein said single fluid transmission line is in the form of a length of tubing which is resistant to kinking or flattening in use of the device.

13. A device as claimed in any one of claims 2 to 12 wherein said fluid transmission line is bonded or otherwise connected to said cuff and said pump means.

14. A device as claimed in any one of claims 1 to 13 wherein said single fluid transmission line is in two parts having a first length attached or bonded to said pump means and a second portion bonded or attached to said cuff portion and there being provided means for connecting said first and second portions of said fluid transmission line together for ease of surgical implantation.

15. A device as claimed in any one of claims 1 to 14 wherein said flexible cuff portion is generally C-shaped and comprises a generally C-shaped non-elastic backing or outer surface and a corresponding generally C-shaped inner elastic membrane which inflates upon action of pressurised fluid entering said cuff portion to a generally C-shaped form wherein the radius of curvature of the inner elastic member is reduced but is parallel to the radius of curvature of the membrane in a deflated condition.

-2116. A device as claimed in any one of claims 1 to 15 wherein said cuff portion is in the form of a one piece silicone rubber cuff manufactured using a dipped or moulded shell.

17. A device as claimed in any one of claims 2 to 16 wherein said pump means is provided with a "block out" valve formed and arranged to maintain the cuff portion in an open condition during the healing process required after implantation of the sphincter device.

18. A flexible cuff for occulding a body passage and suitable for use with AUS devices including a device as claimed in claim 1 wherein said flexible cuff is generally C-shaped and comprises a generally C-shaped non-elastic backing or outer surface and a corresponding generally C-shaped inner elastic membrane which inflates upon action of pressurised fluid entering said cuff portion to a generally C-shaped form wherein th-_ radius of curvature of the inner elastic membrane is reduced but is substantially parallel to the radius of curvature of the membrane in a deflated condition.

19. A flexible cuff as claimed in claim 18 wherein said cuff portion is in the form of a one piece silicone rubber cuff manufactured using a dipped or moulded shell.

20. A method for occluding a body passage comprising the steps of:

-22providing a implantable sphincter device according to claim 1; surgically implanting said device with the flexible cuff portion surrounding a body passage to be occluded; pressurising said fluid reservoir so as to pump fluid contained therein through the body of the device, through said single fluid transmission line and into the cuff portion and so as to inflate it and thereby occlude the body passage surrounded by said cuff.

21. An implantable sphincter device substantially as described hereinbefore and with reference to Figs. 1 to 5 of the accompanying drawings.

22. A flexible cuff substantially as described hereinbefore and with reference to Figs. 1 and 3 to 5 of the accompanying drawings.