The invention relates to a medical implant that restores self-determined control of urinary flow lost due to illness, accident or other reasons.
Many types of artificial urethral sphincters are known for treating urinary incontinence. They are used when such remedies as the outpatient therapy, the pharmacological therapy and the pelvic re-education are not effective. The artificial urethral sphincters are used also as alternative to the traditional surgical techniques, which provide a reconstruction of the bladder support structures. Typically, such artificial sphincter can be provided by a valve structure to be implanted in the urethra, in particular, of a male or female patient, e.g. of a type disclosed in WO2013144770 which shows a variety of valve designs. A challenge for valve designs to be used as urethral sphincter is that the urinary tract may be contaminated by impurities, e.g. kidney and urinary stones. Patients suffering from incontinence problems may often be prone to other ailments and when suffering such conditions, the presence of an artificial sphincter may be problematic. Another challenge for dealing with incontinence issues is that the bladder, when not relieved, may rupture, which led to a serious health condition.
The invention aims to provide an implantable tube valve for implanting in a urinary tract comprising a valve member having a pivot part mounted inside the tube and pivotable between an open position and a closed position, that aims to mitigate such problems.
It is proposed to provide and implantable tube valve for implanting in a urinary tract, comprising: an implantable tube having an inner tube wall extending between two axial tube ends; a valve member mounted inside the tube and pivotable between an open position and a closed position and an actuator for pivoting the valve member between the open to the closed position; wherein the valve member comprises a pivot part constructed to pivot around a pivot axis oriented lateral relative to the tube; said pivot part formed as a substantially tubal orifice on side of the pivot axis, aligned, when in open position, to the tube, and said pivot part formed as a single beak part, on the other side of the pivot axis; the beak part having a sealing edge contacting the inner tube wall, when pivoted in the closed position, the valve member thereby closing off passage through the implantable tube; said valve member provided with a safety mechanism including a biasing element, actuator, and the pivot part, wherein the beak part is arranged to pivot the pivot part towards the open position when a pressure exerted on the beak part exceeds a predetermined pressure.
Another aspect of the invention concerns a system of a wireless charging device and an implantable tube device as herein disclosed.
The invention will be further elucidated in the figures:
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs as read in the context of the description and drawings. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. In some instances, detailed descriptions of well-known devices and methods may be omitted so as not to obscure the description of the present systems and methods. Terminology used for describing particular embodiments is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising” specify the presence of stated features but do not preclude the presence or addition of one or more other features. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control.
The term “mount” is used in its ordinary meaning to emphasize that many mounting arrangements are possible. These arrangements include physical shaft mounts, ball bearing mounts or any other mechanical arrangement providing a rotational degree of freedom for the valve member mounted in the mount. The rotational degree of freedom defines an axis of rotation or pivot axis that is transverse to the implantable tube. Preferably, the mount is formed partly by the tube, and a corresponding mount part formed by the valve member.
The term “conformal to” is used in its ordinary meaning to indicate the form following nature of the identified features, meaning that shape and size are similar for a substantial part of said features. In mathematical sense the meaning conformal indicates that the features preserve shape on a local scale. To illustrate that some deviation may be allowed, depending on the specifics of the application it is considered that certain features, e.g. a valve member's outer and inner face are considered conformal if a thickness between the two varies with e.g. less than 10%.
In stricter sense, it is considered that ‘contiguous to’ means that the form is not only similar, but identical so that there virtually no or only a very small gap between the two features, e.g. less than 0.1 mm. In a more abstract sense, the term ‘coincides with’ is used to indicate that a feature is enveloped by a notional feature coinciding with an outer face over a substantial part of said feature.
By the term ‘extending continuously’ e.g. between axial tube ends, it is indicated that there are no substantial deviations present between said extensions, notably no or very limited protruding outer features, in respect of the implantable tube. In particular, the implantable tube extending continuously between the axial tube ends indicates that there is no or very limited spatial deviation from the tube form along the entire tube. The term continuous does nevertheless not preclude the presence of minor protrusions or depressions, e.g. for forming an actuator housing, sealing edge, mounting or valve seat on a smaller scale or for forming a rugged surface e.g. for fixed insertion in the human vessel, e.g. in the form known for stents. It is indicated on a larger scale that the general flow through the object may be unobstructed due to the tube's continuous form, or that the object itself does not substantially deviate from a tube form. In particular, depending on its application, the actuator actuating the valve member is shaped in elongated form along the tube in a way that can be absorbed by stretching the surrounding tissue, e.g. the urinary tract.
A ‘heating circuit’ may comprise one or more analog or digital hardwire elements configured to perform operational acts in accordance with the present systems and methods, such as to provide control signals to the various other module components. The processor may be a dedicated processor for performing in accordance with the present system or may be a general-purpose processor wherein only one of many functions operates for performing in accordance with the present system. The processor may operate utilizing a program portion, multiple program segments, or may be a hardware device utilizing a dedicated or multi-purpose integrated circuit. Any type of processor may be used such as dedicated or shared one. The processor may include micro-controllers, central processing units (CPUs), digital signal processor s (DSPs), ASICs, or any other processor(s) or controller(s) such as digital optical devices, or analog electrical circuits that perform the same functions, and employ electronic techniques and architecture. The controller or processor may further comprise a memory that may be part of or operationally coupled to the controller. The memory may be any suitable type of memory where data is stored. Any medium known or developed that can store and/or transmit information suitable for use with the present systems and methods may be used as a memory. The memory may also store user preferences and/or application data accessible by the controller for configuring it to perform operational acts in accordance with the present systems and methods.
While example embodiments are shown for systems and methods, also alternative ways may be envisaged by those skilled in the art having the benefit of the present disclosure for achieving a similar function and result. E.g. some components may be combined or split up into one or more alternative components. Finally, these embodiments are intended to be merely illustrative of the present system and should not be construed as limiting the appended claims to any particular embodiment or group of embodiments.
Thus, while the present system has been described in particular detail with reference to specific exemplary embodiments thereof, it should also be appreciated that numerous modifications and alternative embodiments may be devised by those having ordinary skill in the art without departing from the scope of the present systems and methods as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative manner and are not intended to limit the scope of the appended claims.
Any reference signs in the claims do not limit their scope; several “means” may be represented by the same or different item(s) or implemented structure or function; any of the disclosed devices or portions thereof may be combined together or separated into further portions unless specifically stated otherwise. The mere fact that certain measures are recited in mutually different claims does not indicate that a combination of these measures cannot be used to advantage.
In
Turning now to
Pivotable cam member 410 is preferentially designed as a separate part on the outside of the tube 110, leading to only a very minute extension of the tube contour 113 in lateral direction. The pivotable cam member 410 may be designed having a curved inner and outer surface concentrically aligned with the tube 110 to further limit the extension of the tube contour 113.
Heating circuit 425 is preferably geared to a wireless charging device (not shown) but may also be powered by other means, e.g. a battery pack etc.
An external control unit may establish a wireless connection to the implant, supplies the power and the control signals for opening and closing. The implant itself may or may not have a power storage and will be inactive between switching operations. For wearers with limited endogenous control capabilities, it is possible to imagine the control unit giving a signal at equidistant intervals when the bladder should be emptied. For wearers who are in medical or similar facilities, the control unit may enable a connection, to be defined in more detail, to a higher-level patient management system in order to inform the staff of the pending bladder emptying.
In the shown embodiment the heating circuit comprises a charging capacitor (not shown) electrically connected to a charging antenna 430 (
The logic may have further gearing options, e.g. a (wireless) readout, such as status check options or reset options, and is preferably operated by a coded signal that only activates the heating circuit 425 when a corresponding security code is transmitted. In its simplest form, the wireless charging system functions as a bistate switch, switching the valve member 120 from open to closed position or from closed to open, depending on the initial arrangement.
The outer surface of the tube 110 may be covered by a foundation 190, comprising a material that facilitates adhesion to the lumen of the human vessel the implantable tube valve 100 is implanted in, such as a biocompatible meshed, porous or fabric material. Alternatively, the foundation 190 or tube 110 may comprise radially extending protrusions, e.g. spikes or hooks that form a mechanical bonding with the surrounding tissue, thereby fixating the implantable tube valve 100 to the vessel lumen.
The tension wires M1, M2 may reversibly contract when heated by the heating circuit and expand when cooled, thereby providing an actuation force to the pivotable cam member 410. Alternatively, the tension wires M1, M2 may reversibly expand when heated by the heating circuit and contract when cooled. Preferably, the tension wires M1, M2 are of a form that contracts when heated. Shape metal alloy suitable for such may for instance be a NiTi alloy known as Nitinol, but other shape metal alloys can be used to purpose.
The actuation force may be provided by the tension wires M1, M2 being directly coupled to the pivotable cam member 410, e.g. by being soldered, welded, glued or threaded to each other. Preferably, at least one of the tension wires M1, M2 is coupled to a connector, with said connector being mounted in the pivotable cam member 410. For example, each of tension wires M1, M2 may be mounted to the pivotable cam member by means of actuator connector 450. The actuator connector 450 may comprise a cylindrically rounded end engageable with a cylindrically rounded cutout on the pivotable cam member to form a rotatable connection. A benefit of having a cylindrically rounded contact surface between the actuator connector 450 and the pivotable cam member 410 may be that the actuation force on the actuator connector 450 is exclusively converted into a torque on the pivotable cam member 410, which may facilitate maintaining proper alignment between the pivotable cam member and the actuator connector. Conversely, in e.g. a conical contact surface, the actuation force is converted into a torque as well as an axial force, possibly destabilizing or locking the connection between the pivotable cam member 410 and the actuator connector 450. The actuator connector 450 may be an integrally formed part of the tension wires M1, M2. Alternatively, the actuator connector 450 may be a separate part which is assembled to each of tension wires M1, M2 e.g. by soldering, welding, gluing or threading.
Tension wires M1, M2 may be mechanically connected to at least two respective terminals (+) (−) of the heating circuit at one end, to provide a current running therethrough, and mechanically connected to the pivotable cam member 410 at another end, so that the current runs through the tension wire M1 and M2 respectively, without branching off to the pivotable cam member 410. Each of the tension wires M1, M2 may be electrically connected to a positive and a negative terminal on the heating circuit 425, such that a closed current loop is formed without current passing from the connector 450 to pivotable cam member 410. This has as benefit, that no currents pass from connector 450 to pivotable cam member 410, ensuring that connectors 450 can be freely mounted without running into fixation by microwelds that would arise from such currents.
When a pressure is increased the torque will increase also that is exerted by the beak part 114 to counteract the biasing element 800. This will result in a partial opening of the beak part 114, to relieve some of the pressure and keep the bladder pressure below a threshold pressure which is important for the safety of the patient, as a bladder rupture due to overpressure may have life-threatening consequences.
Depending on the design of the biasing element, a bistable characteristic of the biasing element (e.g.: by a snap force design) may result in (sudden) yielding of the beak part to the open position, depicted in
The depicted steps 3A-C are in addition to a voluntary movement of the valve member from a closed position to an open position, by actively pivoting pivot part 115 by an actuator, e.g. of a design depicted in
For a practical dimensioning an exemplary tube inner having diameter of 7 mm and a beak part angle of alpha 30 degrees, this amounts to an elliptical area having a length axis of
a=d/2 tan(alpha/2)) which amounts to about 13 mm.
which amounts to a projected area of
A=pi a·d
and an effective force contact point eccentric to the rotational axis of
x=4a/3pi
A resultant torque would than be given by
M=p·A·x; which can be substituted to
A resultant maximum torque, for d=7 mm; alpha is 30 degrees and a pressure difference of 0.2 bar could amount to 7.9.10−3 N.m, to be provided to by the biasing element 800.
The biasing element 800 provides a counter torque that is determined by the beak angle in closed position, and a resultant biasing force exerted by the bias member to the pivot member, resulting in a torque that can be expressed as
Fd*d
where Fd is a biasing force and d is the effective arm, depending on the effective force contact point eccentric to the rotational axis of the pivot part. This force is the ‘safety force’ that safely holds closed the beak part in closed position, and is dependent on the extent of the beak part, since the resultant torque exerted by pressure force is dependent on the length of the beak part 114, that results in an effective arm p and corresponding torque
Fp*p
where Fp is the effective force developed by the difference pressure and dependent on the projected area of impact, and arm p which are both dependent on the length of the arm.
In case Fp*p>Fd*d, the pivot part 115 will pivot towards the open position.
In a first step S1 one starts with a hollow tube A with inner diameter d1 filled with a first notional body B also with diameter d1. Accordingly, a solid inner body is formed as an inner member contiguous to the tube wall 111. In a second step S2 body B is intersected with another notional body C also of diameter d1 under an angle alfa, resulting in a remaining intersection body of cylinders B and C. Valve member, in particular its sealing edge is thus formed by an intersection curve of a first and second notional bodies B and C, the first notional body B coinciding with the inner tube wall A and the second notional body C formed by pivoting the first notional body B over the pivot part D. Body B is thus cut off by an intersecting shape C of the same shape as the hollow inner cylinder but that is angled relative to the longitudinal axis of the tube A. In this way pivot point D′ is created on an intersection curve between four segments B′, B″, C′, C″ resulting in stable positions within inner tube A. The respective angle alfa between longitudinal axes of tube A and shape C defines the rotation angle of the valve member thus formed.
In a third step S3 section C* is pivoted towards section B*, around pivot axis D′, such that there is no material outside the rotation, and the cylinder surfaces of notional body B smoothly transfers into cylinder surface of notional body C via a further notional body D coinciding with sphere segments E′ and E″ forming a pivot part D. The valve member 120 can now rotate between the two positions B* and C* over rotation angle alfa. By shaping a pivot part D in sphere form a rotation axis is defined. Pivot part D forms a transition area between the two angled cylinder forms B and C so that the valve member has a sealing edge with an edge face 115-3 proximal to the pivot points that coincide with a notional sphere body D formed by pivoting the intersection curve B* towards C*. In this way, the segments E′ and E″ deviate from the cylindrical forms of notional bodies B and C, so that the valve can smoothly pivot without a gap inside the tube inner wall or with only a very small gap. To further prevent urine or other watery fluids to enter the gap between valve member and inner tube wall, these or parts thereof may be formed by a hydrophobic material.
In fourth step S4, the valve member 120 is completed by removing one of the beak parts B′ and cutting out inner cylinder F, collinear with cylinder body B, with a diameter d2. B′ and C are still cylinder surfaces, E′ is still sphere segments.
pivot part D may be sphere shaped and rear edge F of beak part B follows a full circumference of inner tube wall A. Protruding ridge part R may aligns with rear edge F of the beak part B. The ridge part R limits the cross section of inner wall of tube A but at the same time forms a spherical contact face for rotation of pivot part D. Ridge part R may prevent small debris entering the rotating outer face of the pivot part D. Ridge part only extends over an outer semi halve circumference of the tube wall. The arrangements depicted in the embodiments are formed by three major constituents, notably, a valve member, actuator arrangement and powering device. These elements may be combined to benefit to provide the tiny dimensions of an implantable tube, but may be used separately for other applications, notably, valve arrangements that provide larger passage through the implantable tube where the actuator may be formed by other means. Also, the embodiments were directed to idealized shapes, but in practice may be suitably (de) formed e.g. in round, not necessarily circular forms and rotation symmetric, not necessarily spheric shapes but aspheric shapes for example, ellipsoid shapes. Further aspects of the invention are formed by an implantable tube as described in the above wherein the mount is formed by opposite shaft members protruding from the valve member through the tube wall thereby forming an axis of rotation. The heating circuit may be geared to a wireless charging device, the heating circuit electrically connected to a charging capacitor and a charging antenna arranged along the implantable tube; and wherein the heating circuit comprises logic to heat a first or second tension wire when the charging capacitor is charged with a threshold charge, charged by the charging antenna.
Number | Date | Country | Kind |
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2028427 | Jun 2021 | NL | national |
Filing Document | Filing Date | Country | Kind |
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PCT/NL2022/050316 | 6/8/2022 | WO |