Closing system with electronic control

Translation of description of equivalent WO 03043534 A2

p0001Closure system and method for electronically controlling

p0002The present invention relates to a closure system and a method suitable for this purpose for the selective opening and closing of a tubular body organ.

p0003From DE 43 31 658 an implantable device for selectively opening and closing tubular body organs is known, wherein an insertable in the tubular body organ elongated valve body is provided. The valve body has a safety device which can be selectively closed and released. To this end the valve body has a flexible tube portion in which an inflatable member is arranged which can be inflated by a fluid and then closes the lumen of the tube portion. Both opening and closing is effected by a manual manipulation, that is, the inflation of the inflation body is carried out by a manual operation of a pump, and the opening is done by a manual actuation of a switch. Basically, however, ensure in the known system that the inflatable body is not so strongly inflated that to a the body organ in consequence of frequent opening and closing also enlarges and expands, and on the other hand, the pressure generated by the inflatable body, blood circulation would prevent the body organ and thus would die the tissue of the body organ. These specifications require so that the closing of the body organ with the known system is only possible within a limited pressure range, wherein contrast resultant pressure peaks or briefly occurring pressure loads or swells in the body organ, a secure closure of the body organ can not ensure that the known system is not suitable to be tracked briefly.

p0004An object of the present invention is, therefore, the known locking system or the known method for selectively opening and closing of a tubular body organ in such a way that counteracts briefly in occurring to be occluded body organ pressure increases and necrosis is almost impossible.

p0005Another object of the present invention is to provide a closure system which ensures continence at any time.

p0006the objects are achieved device technology with the features of claim 1 and process technology with the features of claim 9.

p0007According to the application, the closure system or according to the application process for selectively opening and closing of a tubular body organ providing a closure member and a the closure element controlling control system, wherein the control system adjusts a first state of the locking system and a deviation from the first state self-regulating to the first state returns. This measure according to the application is achieved enough that when occurring pressure peaks or payable by coughing, sneezing, laughing or bending over to continue to fulfill the duties required of the locking system. This measure according to the application, for example, when the closure system is applied in the urethra, a sphincter replacement system are provided, which replaces the function of the external sphincter of the urethra in adult humans. This according to the application lock system can thus be used as an implantable adaptive fine-sensory sphincter replacement system. The fact that only a short time, a first state of the control system is exited by pressure peaks, the necrosis is reduced or Nekroseerscheinungen can be prevented. By according to the application lock system is thus avoided that a constantly high closing pressure on the body organ or the urethra acts, thus protecting the surrounding tissue of the body organ would lead to necrosis or inflammation. Since according to the application lock system provides an easy-conceived self-regulation, also implanting in the human body is safe. Moreover, it is possible to manually control the voiding through this easy to use locking system, wherein the control of the shutter system automatically by a tap of the neurological signals directly to the nerve pathway in the body organ ter in the case of the urethra of the sphincter Urethrer using an artificial Synapsis is possible. With the registration closing system in accordance, it is also possible that due to the simplicity of the locking system of the energy consumption is kept low and thus a long service life is given. The registration closing system in accordance of the patient is by ensuring its continence with this implant a large measure of quality of life back and is not restricted by the maintenance of the system in its operating range.

p0008Further advantageous embodiments of the present invention are subject of the claims.

p0009If the control system configured with the closure member according to claim 2 as a closed circuit, there is a separate feed of the transfer medium, for example hydraulic fluid not required.

p0010With the features set forth in claim 3, the self-regulating closing system will be implemented in a simple manner, so that the locking system as such is easy to implant and has only a low power consumption. Self-regulation is achieved in particular through the mutual opening and closing the shut-off valves. However, at this point it should be noted that even in place of the pump means and first check valve and a fast-acting pump or fast switching actuator can be used.

p0011In order to set the best possible self-regulation according to body organ, ie the closing pressure is maintained at a certain threshold and in this regard a corresponding working pressure can be adjusted, so are companies different sensor elements provided which optimally brings to an appropriate position to the self-regulatory measure.

p0012Further advantageous embodiments are the subject matter of the other dependent claims.

p0013Based on the following drawing, a preferred embodiment will be described ment of the application object.

p0014In Fig. 1A, the sealing system is shown having a urethra as body organ selectively opens and closes in this case. The urethra comprises in the application closing system in accordance to a closing element 1, which is hydraulically controlled in this embodiment. On this occasion, it is pointed out that any other drive is also conceivable. To the closing element 1 is a control system 3, in this case hydraulically connectable. The control system 3 serves to set a first state of the locking system, such as a closed state of the closing element 1,. For this purpose, the control system 3 in the hydraulic version, a first reservoir 5 on to build up a certain pressure, so-called closing pressure on the closing element 1 through a pump means 7th The incoming to the closing element connecting line is divided into a first feed line ZI and a second feed line Z2, the first feed line having the pump device 7, preferably a first shut-off valve VI and the second supply line, a second Shut-off valve V2, whereby both the first supply line and the second supply line is connected to the first reservoir fifth Conventionally, according to the application lock system also only be used as a device for selectively opening and closing of a body organ, in this case the urethra. For operating the selectively opening and closing, it is advantageous when the pumping device 7, the first stop valve VI, and the second shutoff valve V2 are connected to a control unit 11 which takes over the conventional opening and closing of the closure element the first According to the application closure system further includes a first sensor unit S, which is preferably provided upstream of the closing element 1, the tubular body organ, a second sensor unit S2, which measures the pressure in the connecting line and a third sensor unit S3 of the pump device 7. In order for a differential pressure measurement is possible.

p0015The registration closing system according now works on the following principle.

p0016The pump device 7 uses of the reservoir 5 as the feed stock and generates a closing pressure on the closing element 1, which is selected such that the closing pressure the body organ seals on the closure member, but does not affect the blood circulation of the body organ. The closing pressure corresponds to a pressure range which is so dependent on different parameters, such. As body organ, vessel thickness, blood flow strength. In a briefly occurring pressure rise in the body organ, such as the urethra in the bladder by coughing, sneezing, laughing, or other helpful effort, the closing pressure is not enough and the flow in the body organ would be held briefly. In this case it is advantageous if the closing pressure also briefly increased to thus continue to maintain the tightness of the body organ upright. The registration with the closing system in accordance induced, short-term increase of the closing pressure does not lead to an over a- necrosis, ie the circulation of the body organ is only briefly affected and is therefore not for the body organ damaging. In order to maintain this mechanism, it is necessary that the control system has three different pressure ranges. In the embodiment shown in Figure 1A, the pump device 7, which is configured for example as a fast-action pump or as fast actuator generates, on the first stop valve VI the required closing pressure. For this purpose, the second shut-off valve must be closed V2. Upon reaching the closing pressure, the first check valve VI is closed, the pump device 7 to the first shut-off valve VI builds up a closing pressure against the increased working pressure. Should be carried out by the body organ with the closing element of the flow rate, so only the second shut-off valve V2 must be opened in order to reduce the closing pressure over the reservoir. 5 but kicking now upstream of the closing element 1 pressure peaks and briefly sustained pressure loads occur, they are associated with the sensor device Sl registered or recorded and transmitted to the control unit 11th The control unit 11 opens the first check valve VI nearly simultaneously, so that the increased working pressure, the closure member 1 applied and thus guarantees a short time, that the body organ is sealed against the pressure peaks. Here, it is conceivable that depending on the blood circulation function of the body organ, the control unit 11, the first check valve again closes after a time constant and the second shut-off valve opens to turn down from the elevated operating pressure to the required closing pressure. At the same time, or temporarily can then again the pump device 7 an increased working pressure, which is applied to the first working valve VI build, and thus prepare for a second operation.

p0017In this way, therefore according to the application, the control system 3 capable of a first state of the locking system, which is conventionally be compared to the closing of the body organ via the closing element 1 via the selective opening, a deviation from the first state self-regulating to the first state due. With this measure it is achieved that the closure system met in any situation, so even with loads as coughing or sneezing, which asked to the closure system task. Since the closing pressure is adapted by means of a control rule the feinsensori- in the bodily organ upstream prevailing pressure and bladder pressure in the urinary bladder, Nekroseerscheinungen be prevented, the normally as caused by a constantly high closing pressure, whereby the blood circulation of the body organ is suppressed, thus causing long-term damage.

p0018At this point should be emphasized again that as shown in Figure 1A, the pump device 7 can be replaced via a normal pump in combination with a second reservoir R2 and a third shut-off valve V3. In this case, compared to the increased closing pressure working pressure is attained characterized in that the pump is open, the third shut-off valve, the reservoir R2 to the required working pressure applied, after which the third shut-off valve V3 is then closed. With this measure it is achieved that the use of a fast-acting pump is not required since the short-term loading of the closing element 1 upon the occurrence of pressure peaks is applied to the built up in the second reservoir R2 operating pressure by opening the first shut-off valve to the closing element.

p0019Basically, to be noted that the sensor elements are not only regarded as pressure sensors, but also the pressure can be determined with capacitive or inductive sensors, as changes in volume can be measured by ultrasound or any inlets or in distance that results in pressure increase, is measured with light. According to a further aspect, the invention relates to a method for electronically controlling an artificial fine metering-sensory sphincter implant, in particular for the prevention of stress incontinence and necrosis of the urethra, and a system for electronic control of an artificial sphincter implant-sensory fine metering. By this invention, which is to a fine sensor and an actuator extended previous system of an artificial sphincter implant are controlled so that both full continence can be ensured and at the same time the risk of necrosis produced by excessive and too long pressure applied to the natural urethra is minimized.

p0020This requires an intelligent electronic control which recognizes different stress situations and avoids by increasing the cuff pressure incontinence under dynamic stress such as coughing or laughing, while ensuring through appropriate pressure reductions alone sufficient circulation of the urethra tissue. Since these electronic circuits come in a medical implant is used, it must meet certain requirements such as reliability over long periods, minimum power consumption, small physical dimensions and individual adaptability.

p0021This results directly^" the further object of the invention. The invention provides a method for the electronic control of an artificial fine-sensory sphincter implant is thus further provided, as defined in claim 12th

p0022The invention provides a system for the electronic control of an artificial fine-sensory sphincter implant is further provided, as defined in claim 25th

p0023Further advantageous and / or preferred embodiments of the invention are subject of the subclaims.

p0024Hereinafter, this aspect of the invention, only by way of example and not limitation, and with reference to the figures as well as advantageous and / or preferred embodiment is described in more detail forms.

p0025The meanings of the reference numerals used are given in the following table. The terms signal and value are used interchangeably herein.

p0026(1 differential pressure signal, differential pressure bladder cuff (2 Monostable threshold signal, safety threshold (3 bistable threshold signal, normal pressure threshold (4 cuff pressure (5 Monostable reference signal integration Zero Offset (6 Monostable threshold signal integration threshold (V form signal (8 Monostable threshold signal form threshold (9) Dynamic load

p0027(10) Monostable threshold signal, pressure equalization threshold

p0028(11) Bladder pressure

p0029(12) output signal or output value of the adding function, lower threshold

p0030(13) output signal or output value of the integrator function

p0031(14) output signal or output value of the differentiator

p0032(15) elevation of the cuff pressure

p0033(16) reduction of the cuff pressure

p0034(17) form

p0035(18) increasing the inlet pressure

p0036(19) output of the integrator function of the delay block

p0037(20) Dynamic load

p0038(21) area of ​​back traveling Integration

p0039(22) area of ​​continuous integration

p0040(23) A method for regulation of the urethra closing pressure by means of an inflatable cuff, a fluid reservoir, a pump and a valve via hydraulic connections

p0041(24) Hydraulic connection

p0042(25) Cuff

p0043(26) Taxable valve

p0044(27) Bi-directional pump

p0045(28) fluid reservoir

p0046(29) admission pressure reservoir

p0047(30) A method for regulation of the urethra closing pressure, by an inflatable cuff, a fluid reservoir, a pump, three valves and one admission pressure reservoir via hydraulic connections

p0048(31) Urethraver final pressure

p0049ferentiatorfunktion (32) Dif

p0050(33) adding he function

p0051(34) integrator function

p0052(35) parameter variation

p0053(36) comparator element

p0054(37) integrator function of the delay block

p0055The figures show

p0056Figure IB:. A schematic functional block diagram without admission pressure reservoir and with the output of the differentiator function as an input signal of the integrator function,

p0057FIG. 2 is a schematic functional block diagram without admission pressure reservoir and with the output of the adding function as an input signal of the integrator function,

p0058FIG. 3 is a schematic functional block diagram with admission pressure reservoir and with the output of the differentiator function as an input signal of the integrator function,

p0059FIG. 4: a schematic functional block diagram with admission pressure reservoir and with the output of the adding function as an input signal of the integrator function, Fig. 5a = Fig. 7a: with sustained dynamic strain the pressure variation in the cuff and in the bladder during brief dynamic loading,

p0060Fig. 5b = Fig. 7b: with sustained dynamic load the waveform of the electronic circuit for short-term dynamic loading,

p0061Fig. 5c = Fig. 7c: with sustained dynamic load the waveform of the integrator system with the output of the differentiator function as an input signal of the integrator function for short-term dynamic loading,

p0062Fig. 5d = 7d. Under prolonged dynamic loading the waveform of the integrator system with the output of the adding function as an input signal of the integrator function for short-term dynamic loading,

p0063Fig. 5e = 7e:. With sustained dynamic strain, the switching states for pressure increase and pressure reduction in the cuff during a brief dynamic loading,

p0064Fig. 6a = Fig. 8a: with sustained dynamic strain the pressure variation in the cuff, the bladder and the form container with brief dynamic loading,

p0065Fig. 6b = 8b. With sustained dynamic load the waveform of the electronic circuit for short-term dynamic loading, Figure 6c = 8c. With sustained dynamic load the waveform of the integrator system with the output of the differentiator, as an input signal of the integrator function for short-term dynamic loading

p0066Fig. 6d = 8d. For sustained dynamic load the waveform of the integrator system with the output of the adding function as an input signal of the integrator function for short-term dynamic loading,

p0067Fig. 6e = 8e. With sustained dynamic strain, the switching states of the pressure increase and pressure reduction in the cuff during a brief dynamic loading,

p0068Fig. 6f = 8f. With sustained dynamic strain, the switching states of the pressure increase in the admission pressure reservoir,

p0069FIG. 6g = Figure 8g. With sustained dynamic strain the course of the integrator signal to control the opening of the valve between cuff and admission pressure reservoir,

p0070Figure 9a:. The integrator signal switching threshold at sustained dynamic strain,

p0071Figure 9b:. The input signals of the integrator function with continuous areas (22) and reflected (21) Integration with sustained dynamic strain, FIG. 10 is the method for regulating the urethral closure pressure without admission pressure reservoir,

p0072Fig. 11: the method for regulating the urethral closure pressure with admission pressure reservoir,

p0073Fig. 12 shows the waveform under dynamic loading, namely 12a absolute pressures, 12b the Urethraverschlussdrucksignal with switching thresholds and 12c the integrator signal with switching thresholds (or integrator system integrator or element), and

p0074FIG. 13 is a functional schematic diagram of artifizi- ellen sphincter implant.

p0075The electronic control of the sphincter implant control can be both digital and analog realized. The method for controlling the sphincter implant, which is the subject of this invention, so that in principle does not change.

p0076The patient is using of variable parameters given the opportunity to customize the behavior of the implant to suit the personal requirements. For an analog control A converters are used to parameter variation D / used, the clock signal may be externally generated and transmitted via the telemetry.

p0077Operation of the electronic controller The electronic control system, which is the subject of this invention consists of fine sensory signals, in particular the differential pressure between the bladder and the cuff or a comparable differential pressure in control commands to the actuator of the implant.

p0078The voltages applied to the signal inputs sensor signals are amplified by amplifier circuits such that moving the signals in operation between the limits imposed by the circuit.

p0079In operation without dynamic load, about the quiet sitting or lying down, the cuff pressure (4) but is in a range, in which the blood supply to the relevant Urethragewe- ensures bes, when increasing the bladder pressure (11) easily lead to incontinence could. Increasing the differential pressure signal or the differential pressure value (1), upon reaching a bistable threshold value (3) of the cuff pressure (4) is lowered (16), the differential pressure signal or the differential pressure value (1) falls below the lowered bistable threshold value (3), the decrease (16) of the cuff pressure (4) terminated. This is done for the analog variant by means of a comparator, which is provided with a hysteresis circuit.

p0080With dynamic loading occurs, the actuator has to assume the function of a healthy sphincter, namely avoid by active pressure transmission, ie the involuntary contraction of the sphincter under dynamic stress incontinence the. At sudden pressure increase, for example when coughing or laughing, must be raised within milliseconds of the cuff pressure (4). As can be expected at a differential pressure of zero of incontinence, falls below the differential pressure signal or the differential pressure value (1) is caused by a non-zero threshold, the actuator system to increase (15) of the cuff pressure (4). To a certain inertia of the actuator to prevent moreover, is provided in the electronic control, to provide this lower threshold, the differential pressure signal or the differential pressure value (1) must be less than only in micturition with an additive, the active component. To achieve this, for the analog variant, the differential pressure signal (1) is differentiated by means of a differentiator and raised the output and the output value (14) of the differentiator using an adder circuit around the lower threshold. In the case of use of a microprocessor, the sensor signal is differentiated numerically by the current signal value is subtracted from the last but one signal value and the result is if positive, added with an offset component. The result serves as a lower threshold (12). By these measures it is achieved that the lower threshold (12) in a sudden increase of the internal bladder pressure (11) the falling differential pressure signal or the differential pressure value (1) runs counter to and thus enables an early activation of the actuator system. The activation of the actuator system for the analog variant by means of a comparator which compares the differential pressure signal (1) with the lower threshold (12). Once through below the differential pressure signal (1) below the lower threshold (12), the actuator is activated, the comparator function to avoid excessive cuff pressure (4) in the unloaded mode is disabled for the analog variant and increases the cuff pressure (4) to a value can be ensured in the continence, the circulation of the urethra tissue concerned may be affected but.

p0081This increase in pressure may, depending on the design of the actuator system, carried out in different ways:

p0082When using an admission pressure reservoir (29) a valve (26) is opened so that there can be a pressure compensation between the admission pressure reservoir (29) and the cuff (25). Due to the flow of fluid at this pressure equalization, the previously selected pressure (17) depending on the design of the cuff (25) and the admission pressure reservoir (29) has to be higher by a specific amount than the desired maximum cuff pressure. The opening of the valve between the admission pressure reservoir (29) and the cuff (25) is time-controlled. Here, for the analog variant in particular an integrator element to be used, which is started simultaneously with the opening of the valve and whose output signal (19) is compared by means of a Komparatorglie- of a monostable threshold value (10). Upon reaching the parity, the valve (26) between the admission pressure reservoir (29) and the cuff (25) is closed again and simultaneously the increase (18) of the form (17) in the previous pressure reservoir (29) is started. Activation of the integrator element which controls for the analog variant the reduction (16) of the cuff pressure (25) is carried out, either simultaneously with the opening or the closing of the valve (26) between the admission pressure reservoir (29) and the cuff (25). The signal that the valve (26) between the admission pressure reservoir (29) and the cuff (25) caused to close, triggers the increase (18) of Vordruk- kes (17) in the admission pressure reservoir (29). The pressure signal of the admission pressure (17), which is also required when using an admission pressure reservoir (29) is compared with the analog variant by means of a comparator element with a monostable threshold value (8) and parity, a signal is triggered which the completion of the elevation (18) of the form (17) initiated. In this use of a microprocessor is programmed so that it behaves in principle as that described analog circuit.

p0083In otherwise inserted actuators without admission pressure reservoir (29) reaching this safety pressure will be registered with a comparator element or a comparator function, the or the differential pressure signal, the differential pressure value (1) compares with a monostable threshold value (2) and the differential pressure signal is exceeded or of the differential pressure value (1) above the threshold (2) triggers a signal which causes the actuator to end the increase (15) the cuff pressure (4). By this signal, the integrator element or integrator function is also activated, which controls the lowering (16) the cuff pressure (4). controls the activation of the integrator element, for the analog variant, the decrease (16) of the cuff pressure (4), may, in particular concerning the interruption of a discharge current circle done of the operational amplifier of the integrator element negative feedback capacitor. Thus can take place and integration starting value is equal to the voltage across the capacitor discharged.

p0084The intelligent behavior of the electronic controller is particularly evident in the fact that with sustained dynamic strain, the decrease (16) of the cuff pressure (4) is delayed. For the analog variant to this, an integrator element is used. By suitable choice of the input signals is achieved, that is reduced in short-term exposure, for example, when getting up from a sitting position, the cuff pressure (4) quite quickly to values ​​that correspond to the safe normal operation without risk of necrosis. With sustained dynamic strain, however, such as physical activities, the cuff pressure (4) is held at the high level until the dynamic load leaves downstream. This behavior is produced for the analog variant characterized in that at the inverting and the non-inverting input of the operational amplifier of the integrator element abut two suitable signals. Firstly, this is a signal to the output (14) of the differentiator element analog signal, in particular either the output (14) of the dif- ferentiatorgliedes itself or the output signal (12) of Addierergliedes. At the other input of the operational amplifier of the integrator element is a monostable reference signal (5). This monostable reference signal (5) is selected such that it can be crossed by the signal present at the other input of the operational amplifier of the integrator element signal with dynamic loads and thus volatile output (14) of the differentiator element. This circuit of the integrator element with the result that the output (13) of the integrator element moves away from the starting point, when the output signal (14) of the differentiator element analog input signal has not or rarely crossed the monostable reference signal (5), ie at low dynamic of strain , If the dynamics of the load on the other hand high, crosses the output signal (14) of the differentiator element analog input signal, the monostable reference signal (5) frequently. Once the output (14) of the differentiator element analog input signal has crossed the monostable reference signal (5), the output signal (13) of the integrator element moves towards the start value. At high dynamics of the strain, the output signal (13) of the integrator element zigzag shape is driven against the start value. For the analog variant is by a comparator element, the output (13) of the integrator element with a constant threshold (6) which does not close the initial value of the output signal (13) of the integrator element must be compared. Once the output (13) of the integrator element reaches this constant threshold (6), the decrease (16) of the cuff pressure (4) is caused. This reduction is carried out by the activation of the comparator element, which causes the actuator system as long as to reduce (16) the cuff pressure (4) caused by the differential pressure signal (1) the lowered bi- stable threshold signal (3) below. The cuff pressure (4) is now back in a safe area in which the Ne krosegefahr is minimal. If a microprocessor is used, this leads numerically in principle the same calculations as the analog circuit and therefore produces a comparable behavior.

p0085Another key feature of this electronic control is the presence of numerous ways to influence the behavior of the system by the variation of parameters from the outside. This can be adapted to the individual requirements of the patient, the artificial fine-sensory sphincter implant, on the one hand, the setting of the parameters to Consummate scarring after implantation, on the other hand in response to changing demands by the patient, such as advancing age or lifestyle changes.

p0086Since one has to limit the number of variable parameters for the analog variant, unlike digital, four parameters for varying been selected that can influence the behavior of the implant significantly.

p0087The monostable offset signal

p0088The monostable offset signal is the additive component, which complements the Augangssignal (14) of the differentiator element the lower switching threshold. By varying the monostable Off- setsignals, a sluggish actuator system or a premature urine flow are compensated.

p0089The bistable threshold signal (3)

p0090The bistable threshold signal (3) can be varied when the cuff pressure (4) already for the circulation of the urethra tissue obtained during normal operation critical values, or when the bistable threshold signal (3) is set so low that the lowering (16) the cuff pressure ( 4) is unreasonable often causes.

p0091The monostable reference signal (5)

p0092By varying the monostable reference signal (5) the rate of integration can be adjusted.

p0093The monostable threshold signal (2)

p0094The monostable threshold signal (2) corresponding to the differential pressure signal or the differential pressure value (1) in which the cuff pressure (4) has a value which ensures at the continence, the circulation of the urethra tissue is impaired but. When the monostable threshold signal (2) is too low, despite increased cuff pressure (4) the differential pressure signal or the differential pressure value (1) may fall below the lower switching threshold and thus trigger a further Duck increase in heavy dynamic stress. If set too high monostable threshold signal (2), the urethra can tissue damage due to the high cuff pressure (4)

p0095or

p0096The monostable threshold signal (8)

p0097By varying the monostable threshold signal (8) the form in the admission pressure reservoir and thus the maximum cuff pressure (4) after the pressure equalization is adjusted.

p0098If a microprocessor is used, there is a priori more opportunities to influence the behavior, to the complete reprogramming.

p0099The method of regulating the cuff pressure

p0100The controlled from the described analog circuit actuators may be of different methods and arrangements operate to produce the desired effect on the urethra. The different configurations and components of the actuators require a customized control electronics. Below are two hydraulic methods are described by way of example, one with and one without admission pressure reservoir (29).

p0101As for the method for regulating the cuff pressure (4) by means of a pump (27), a valve (26) and a fluid reservoir (28) via hydraulic connections (24), see FIG. 10. In this method for regulating the cuff pressure (4) the use of a pump (27) is provided, which the hydraulic flow to oppose a low resistance at standstill. Upon opening of the valve (26) for reducing (16) the cuff pressure (4) takes place between the cuff (25) and fluid reservoir (28) a pressure compensation. The valve (26) can be placed both between the cuff (25) and pump (27) and between the pump (27) and fluid reservoir (28).

p0102As for the method for regulating the cuff pressure (4) by means of a pump (27), a supply pressure reservoir (29), three valves (26) and a fluid reservoir (28) via hydraulic connections (24), see FIG. 11.

p0103The use of an admission pressure reservoir (29) in this method allows a flash-like increase (15) of the cuff pressure (4). However, a further pressure sensor is required, which controls the regulation of the form (17). After triggering the increase (15) of the cuff pressure (4) by opening valve (26) between the admission pressure reservoir (29) and the cuff (25) allows a pressure equalization. The security pressure in the cuff (25) thus depends only on the earlier in the admission pressure reservoir (29) set initial pressure (17). Decisive for the surge is the construction of the admission pressure reservoir (29). The smaller the size, the greater the pressure (17) must be.

p0104As for increasing (18) of the form (17) the period after Increase (15) the cuff pressure (4) is used, so for a certain period, no further increase (15) the cuff pressure (4) can be triggered, has no high requirements are placed on speed in the selection of the pump (27). Operation at low voltages is made possible by.

p0105The miction

p0106To initiate voiding a signal is generated externally. This signal causes the actuator system to decrease (16) of the cuff pressure () and disabled beyond the analog electronic circuit except for the comparator element, which limits the Cuffnormaldruck upwards.

p0107After completion of the micturition a second external signal is generated which initiates the increase (15) the cuff pressure (4) again. The cuff pressure (4) is increased until the differential pressure signal or the differential pressure value (1) reaches the bistable threshold value (3). By a comparator, the remaining analog electronic circuit is thus reactivated.

p0108In summary therefore includes this aspect of the invention, the following embodiments:

p0109According to embodiment 1, the process for electronic control of an artificial fine-sensory sphincter implant is characterized in that the behavior of not less least one sensor signal in an analog or digital electronic circuit by means of computing and Komparatorfunk- functions such converted and compared with reference values ​​that an actuator is controlled such that the cuff pressure or the differential pressure between the cuff and bladder in either a two thresholds moves limited low range or above a specific safety pressure.

p0110According to Embodiment 2, the sensor signal or sensor value (1) of the electronic circuit according to embodiment 1 in that it is analogous to the difference between the bubble internal pressure (11) and cuff pressure (4) acts.

p0111According to Embodiment 3, the differentiator function of the electronic circuit according to Embodiment 1 is characterized in that the output signal or the output value (14) of the differentiator of the differentiation of the course of the sensor signal (1) corresponding to Embodiment 2. FIG.

p0112According to embodiment 4, the adding function is marked with a monostable offset signal or offset value of the electronic circuit according to embodiment 1 in that the output signal or the Ausgangsswert (12) of the adding the to a monostable offset signal or a monostable offset increased output and output value ( 14) of the differentiator function according to embodiment 3 corresponds. According to embodiment 5, the comparator function is marked with a bistable threshold signal or threshold value (3) of the electronic circuit according to embodiment 1 in that in the event of parity or crossover of the sensor signal or sensor value (1) according to Embodiment 2 with the bistable threshold signal or the bistable threshold value (3) of this threshold signal or this threshold (3) is lowered or raised to the conditional by the hysteresis amount and a signal is triggered, the actuator system to decrease (16) of the cuff pressure (4) causes long until by repeated parity or even twice crosses the sensor signal (1) according to embodiment 2 with the bistable threshold signal or the bistable threshold value (3) a signal is triggered which causes the actuator system to terminate the lowering (16) the cuff pressure (4) and the bistable threshold signal or the bistable threshold value (3) raises or lowers to the caused by the hysteresis amount.

p0113According to embodiment 6, the comparator of the electronic circuit according to Embodiment 1 is characterized in that the sensor signal or sensor value (1) according to embodiment 2 with the output signal or the output value (12) of the adding function according to embodiment 4 is compared in such a way that for the event of parity or the intersection of the sensor ignals or the sensor value (1) according to embodiment 2 with the output signal and the output value (12) of the adding function according to embodiment 4, a signal is triggered which causes the actuator to increase (15) of the cuff pressure (4) led and the comparator function according to embodiment 5 overrides.

p0114According to embodiment 7, the integrator function is marked with a monostable reference signal or a monostable reference value (5) and a constant start value of the electronic circuit according to embodiment 1 in that either

p0115a) the monostable reference signal or the monostable reference value (5) to the monostable offset signal or offset value according to embodiment 4 is different and is selected such that the output signal or the output value (12) of the adding function according to embodiment 4 in activity the monostable reference signal or . the monostable reference value (5) crosses, and that the integrator function integrates the difference between the output signal and the output value (12) of the adding function according to embodiment 4 and the monostable reference signal or the monostable reference value (5) in such a continuously or numerically that with low activity of the output signal and the output value (14) of the differentiator function according to embodiment 3, the output signal and the output value (13) of the integrator function from the start value and high activity of the output signal and the output value (14) of the differentiator function according to embodiment 3 on the start value is moving, see Fig. ld, Fig. 2D, Fig. 3d, Fig. 4D and Fig. 5, or

p0116b) the monostable reference signal or the monostable reference value (5) is not equal to the output signal or output value (14) of the differentiator function according to embodiment 3 is at a low activity and is chosen such that the output signal or the output value (14) of the differentiator function according to embodiment 3 in activity crosses the monostable reference signal or the monostable reference value (5), and that the integrator function, the difference between the output signal and the output value (14) of the differentiator function according to embodiment 3 and the monostable reference signal or the monostable reference value (5) in such a continuous or integrated numerically that in low activity of the output signal and the output value (14) the differentiator to embodiment 3, the output signal and the output value (13) of the integrator function continuously from the start value and the differentiator is moving at a high activity of the output signal and the output value (14) according to embodiment 3 to the start value, see Fig. lc, Fig. 2c, Fig. 3c, Fig. 4c and Fig. 5.

p0117According to embodiment 8, the delay function of the electronic circuit according to Embodiment 1 with the use of a method for regulating the cuff pressure (4) with pre-pressure container (29), characterized in that the triggering of the pressure equalization between the admission pressure reservoir (29) and the cuff (25) by the comparator function according to embodiment 6, the delay function is activated and triggers a signal when the set delay time, which causes the actuator system to terminate the pressure compensation between the admission pressure reservoir (29) and the cuff (25) and the integrator function according to embodiment 7 is activated such that upon activation the output signal or the output value (13) of the integrator function according to Embodiment 7 corresponds to the constant start value on the embodiment, 7th

p0118According to embodiment 9, the comparator with a monostable threshold signal or threshold value (2) of the electronic circuit according to embodiment 1 is characterized in that in the event of parity or crossover of the sensor signal or sensor value (1) according to Embodiment 2 with the monostable threshold signal or the monostable threshold value (2) a signal is triggered which causes the actuator to end the increase (15) the cuff pressure (4) causes and the integrator function is activated according to embodiment 7 such that upon activation the output signal or the output value (13) the integrator function according to embodiment 7 corresponds to the constant start value on the embodiment. 7

p0119According to embodiment 10 the comparator function is marked with a monostable threshold signal or a monostable threshold value (6) of the electronic circuit according to embodiment 1 in that in the event of parity or crossover of the output signal or the output value (13) of the integrator function according to Embodiment 7 is triggered a signal of the monostable threshold signal or threshold value (6), causes the actuator system to decrease (16) the cuff pressure (4) and / or the comparator function is activated according to embodiment 5th According to embodiment 11 the monostable offset signal or the monostable offset value according to Embodiment 4 is characterized in that it can be varied by variation of parameters from the outside.

p0120According to embodiment 12 the bistable threshold signal or the bistable threshold value (3) according to Embodiment 5 is characterized in that it can be varied by variation of parameters from the outside.

p0121According to embodiment 13 the monostable reference signal or the monostable reference value (5) according to embodiment 7 is characterized in that it can be varied by variation of parameters from the outside.

p0122After Ausführungsfom 14 the monostable threshold signal or the monostable threshold value (2) according to Embodiment 9 in that it can be varied by variation of parameters from the outside.

p0123According to embodiment 15, the method for controlling the voiding of the electronic circuit according to embodiment 1 is characterized in that an external signal causes the activation of the micturition the actuators to lower the urethral closure pressure and the electronic circuit according to embodiment 1 except for the comparator function according to embodiment 5 disabled and to deactivate micturation an external signal causes the actuator system to increase (15) of the cuff pressure (4) causes up for the event of parity or the crossing of the sensor signal (1) according to embodiment 2 with the bistable threshold signal or threshold value (3) according to Embodiment 5, a signal is triggered which activates the electronic circuit according to Embodiment 1. FIG.

p0124In this invention, a novel fine sensory implant is introduced, combining the most important aspects of technological problems of in vivo medical in itself: A reliable fine sensory system, an intelligent, flexible control electronics with low power consumption, a miniaturized and high performance actuators and a sophisticated energy and data transfer. Using the example of this implant, an artificial, adaptive, fine-sensory sphincter, to be discussed in the light of the development history and the methodological criteria Education to select control and alternative design incl. Intensive test for determining individual components, while taking account of similar implants of the latest state of implant technology.

p0125The numbers in brackets refer to the references in the bibliography at the end of this description. The numbers refer to the figures 12a to 12c.

p0126A current system of an artificial Blasenhalssphinkters, exemplified the AMS 800, uses a hand pump in the scrotum or the labia majora, with the urine flow blocking cuff around the urethra (urethra) is placed, is inflated. [6] The problem with this system is the setting of the urethra closing. A to GE ringer pressure results when urine leaks under dynamic loading, which may be caused by laughing, coughing, sneezing or heavy lifting. Excessive pressure on the urethra over a long period can easily result in black tissue necrosis. To avoid this risk, yet put into practice a slight stress incontinence with all its negative social consequences into account.

p0127The artificial fine sensory sphincter implant, which was developed according to the invention, the hand pump replaced by an active hydraulic, which is equipped with a fine sensory system and an intelligent control system. With this system the active pressure transmission can be supported or replaced. The sensor monitors primarily the difference between bladder pressure and cuff pressure. With dynamic loading, the actuator is used to increase the cuff pressure, so that even at these elevated pressures continence is ensured. This may be affected for a short normal circulation of the urethra tissue. The implant can distinguish between one-off and sustained dynamic load.

p0128control

p0129The decisive factor for the function of the artificial fine-sensory sphincter implant is the urethra closure pressure (31). If the urethral closure pressure (31) is negative, loss of urine occurs. The the urethra closing pressure (31) is equivalent signal from the two absolute pressure signals of the cuff (25) and the urinary bladder determined (Fig. 12a). In sudden dynamic load of the stomach interior, this signal is moving rapidly towards zero. In order to ensure a rapid response of the implant in this situation, the following measures:

p0130The lowering of the urethra closing pressure (31) is limited downwardly by a switching threshold that is above of the incontinence range and can be varied during programming.

p0131The course of the urethra closing pressure (31) is differentiated and the positive portion of the lower switching threshold (12) added. The faster the urethral closure pressure (31) drops, the sooner the actuator of the implant due to this measure enabled (ti (Fig. 12b).

p0132This time-critical area is realized by means of analog electronic components to allow a maximum rate of reaction. The activation of the actuators is effected by a comparator which compares the signal of the urethral closure pressure (31) with the lower switching threshold (12).

p0133The use of an admission pressure reservoir allows a lightning reaction of the actuator at low supply voltage. After completion of the pressure equalization (t₂) Is the form (17) up to a maximum value of variable p_Max increased (within t₂ to t₃).

p0134takes place, the reduction of the elevated cuff pressure under-equipped with hysteresis normal pressure threshold (3) controlled by a microprocessor after the end of the dynamic load. In order to obtain a measure of the dynamic loading, the difference from an offset value (5), which can be in programming also varies, and the lower switching threshold (12) is integrated. With sustained dynamic strain, the integration result (13) is pressed zigzag down. Without dynamic load the integration result (13) rises up to a threshold (6), on reaching which the lowering of the cuff pressure is initiated (t₄) (Fig. 12c).

p0135The normal pressure threshold to prevent an excessively high cuff pressure in normal operation. This function is, like the activation of the actuator system, also realized with analog electronic components.

p0136The analog circuit includes four variable parameters that are influenced by means of D / A converter, namely: the rate of differentiation of the Urethraverschlussdruck- signal, the additive offset component of the lower threshold value and the mean value and the hysteresis of the normal pressure threshold. The always-on electronics is thus reduced to a minimum of 6 and a quad operational amplifier digital potentiometer of the analog circuit and the Signal conditioning and the RF receiving module. The total power consumption of electronics amounts to the microprocessor in the power-down mode to less than 0.1 mW.

p0137Programming Software

p0138The programming of the artificial fine-sensory sphincter implant according to the invention is effected by means of an external programming station. About the bidirectional transcutaneous data transfer of the urethral closure pressure and the absolute pressure in the inlet pressure containers are transferred to the programming station. The in vivo pressure measurement coupled with a simultaneous external urodynamisehen investigation facilitates extensive automation of the implant programming. The patient performs defined physical movements, such as rising from a seated position or coughing. From the collected data, together with experience from clinical trials can be evaluated by the software an optimal adjustment of the implant. Subsequently necessary adjustments to the programming, for example, to changing life circumstances of the patient or to a change in behavior of the implanted electronics, are also possible manually.

p0139sensors

p0140An intended function of the artificial sphincter implant requires the use of three pressure sensors that have to measure the pressure at different locations and with different conditions: In the admission pressure reservoir is best done using a surface sensor that can be integrated into the rigid base plate of the pre-pressure container. This capacitive pressure sensor is ans a polysilicon diaphragm and a silicon substrate [1]. Between the polysilicon diaphragm and the silicon substrate, a vacuum is generated in the production, so that creates an absolute pressure sensor. For signal amplification can be, at the small diameter of 100-120 microns of a sensor element, build in parallel a sensor array [2].

p0141If an absolute pressure sensor in the admission pressure reservoir, the absolute pressure in the cuff can also be measured by means of a differential pressure sensor, which measures the difference between Cuff- and form. By a suitable electronic circuit, the absolute pressure of the cuff pressure signal is filtered out to the absolute pressure signal of the pre-pressure container and the pressure differential signal between the cuff and the admission pressure reservoir. This allows the use of an inexpensive and reliable piezoresistive differential pressure sensor, which is connected via hydraulic connections with both the admission pressure reservoir and to the cuff.

p0142To measure bladder pressure is an absolute pressure sensor, similar to an intracranial pressure sensor, embedded in the bladder near the tissue to not puncture the bladder or to open [5]. The pressure measured may not have exactly the bladder pressure, is this but equivalent. electronics

p0143The physical dimensions and the power consumption of the electronic components are in the artificial implant Sphinkterim- not the critical parameter, since both is negligible compared to the characteristics of the actuators. Yet minimization is sought, albeit more emphasis can be placed on reliability and redundant systems.

p0144Probable for the artificial fine-sensory sphincter implant control electronics is similar with respect to the requirements of a modern pacemaker. As in a pacemaker sensor signals are evaluated by a microprocessor and translated into actions of the implant. To minimize the power consumption of the electronics, the microprocessor is operated in the normal operation in the power-down mode. The comparator, the actuator activates upon dynamic strain simultaneously activates the microprocessor.

p0145The use of a programmable via transcutaneous data transmission microprocessor has the decisive advantage that changes such as the lifestyle of the patient or in the behavior of the electronic components can be flexibly responding. The use of analog semiconductor devices, such as a computing circuit for determining the absolute pressure cuff, thereby becomes less critical. With a power consumption of less than 1 uA per operational amplifier the analog components can easily stay permanently activated. The only intermittently active microprocessor can be operated with relatively high clock frequencies, because the relatively high power consumption associated therewith can be easily compensated by a significantly improved performance of the implant.

p0146While one must be connected with up to lkv charged capacitor with a pacemaker (usually via IGBTs), which discharges through the human tissue between the electrodes with several ten amperes within a few milliseconds, are the artificial fine-sensory sphincter implant at a supply voltage of 4.2 V maximum continuous load currents of about 100 mA per switch connected. To this end, MOSFETs offer, which can be operated directly by the microprocessor. Thus, the reliability can be guarantee multiple MOSFETs connected in parallel to cope with the failure of individual components at Schaltaufgäbe still easily can per switching unit. These can be integrated in one multi-chip module (MCM).

p0147The signal conditioning, analog circuit, the A / D conversion, the internal memory and the microprocessor with a multi-I / O module can be used in a mixed-signal ASIC, an Application Specific Integrated Circuit, summarized [4]. This provides an extremely low power consumption, because unlike the use of a commercially available microprocessor, but no unused features still lie fallow consume electricity. This advantage is offset by a high development effort, the results of design, simulation and manufacturing the desired result. For this reason, the prototype of the implant is realized with a commercially available microcontroller. The development of an ASIC would be a disproportionately high temporal as financial expenses for a prototype.

p0148Fuels is typically a lithium-ion battery that is charged via a subcutaneously implanted induction coil. The charge controller of the lithium-ion battery pack is a commercially available IC, which is used for example in mobile phones. It monitors the current flow between the energy transfer module and the battery, he can influence with a MOSFET. Termination, termination and errors are reported to the microprocessor.

p0149actuators

p0150The miniaturization of implantable actuator requires components that meet the high demands of today's medical technology, such as biocompatibility, durability and reliability. In the implantation medicine include silicones and polyurethanes, which are characterized by their biocompatibility, the most commonly used materials. In mechanical and thermal endurance tests, it was found that silicones and polyurethanes quite having equivalent properties. With more than 5 million load cycles durability for use in humans was simulated and confirmed.

p0151The actuators of the artificial fine-sensory sphincter implant consists of electrically active components, the valves and the pump, and from passive, a form chamber, an inflatable cuff and the hydraulic connections (Figure 13). These components must be specially adapted for use in the artificial fine-sensory sphincter implant. Industrial pumps and valves are mainly designed for pressures of Lobar and more. Since the implant maximum pressures below 500 mbar occur, an adapted dimensioning of these components is useful.

p0152The admission pressure reservoir consists of a rigid base plate on an elastic membrane is stretched. Due to the flat structure of the admission pressure reservoir can be integrated into the outer shell of the implant that the elastic membrane can bulge when the pressure increases to the outside.

p0153The crucial function of the artificial fine-sensory sphincter implant is the flash-like increase of the cuff pressure in sudden lowering of Urethraverschlussdruk- kes. In order to keep the time between activation of the actuators and reaching a secure cuff pressure as low as possible, a higher inlet pressure is provided, which can be transmitted to the cuff via the valve 3rd Since the electronic response times achieved in the micro- to nanosecond range ranges, the ultimate gain in response time for the optimization of the system of the admission pressure reservoir, valve 3 and the hydraulic connection is expected. If cash is a flow of 0.2 ml is needed for example to increase the cuff pressure of 70 mbar to 100 and the pressure difference between cuff and admission pressure is container before the pressure equalization Ap concerns with an opening radius of the hose r following proportionality (Eq. 1 ):

p0154t ~. r² -Δp

p0155Reaction times of activation of the actuator until the end of pressure equalization can be realized under 10 ms. For this purpose, a pressure difference of 400 mbar and a Dp = internal radius of the hydraulic connections of about r = 1.0 mm is necessary. With a further increase of the inner radius r shorter reaction times can be realized.

p0156Furthermore, the inertia of the valve 3 causes a further delay, which increases with increasing opening radius r.

p0157The reduction of the cuff pressure takes place through valve 2 into the reservoir. When sizing the valve 2 and the hydraulic connections between cuff and reservoir must be taken to ensure that lowering the cuff pressure is not too fast. If this is the case, due to the inertia of the valve and the oncoming lower switching threshold once again increasing the cuff pressure can be triggered. With an appropriate choice of the cross-sectional opening of the hydraulic connections, this danger can be avoided, however.

p0158Power and data transmission

p0159Regarding the energy and data transmission, the most in common with the artificial urinary bladder [6] [7] let [8] notice. Unlike, for example, the artificial heart, the energy transfer is the artificial fine-sensory sphincter implant only charging the implanted battery, and data transfer is mainly used for programming of the microprocessor. Furthermore, another signal path is to miction used, which is simple for the patient to use. For these conditions the following configuration of the power and data transmission was designed for use in the artificial fine-sensory sphincter implant:

p0160The charging of the implanted rechargeable batteries takes place inductively by placing a charger to a subcutaneously implanted induction coil [3] to allow rapid bidirectional data transmission, in the center of the induction coil, an IR transmitting / receiving module is placed. These optical data transmission requires, as the inductive power transfer, the laying of the external counterpart directly to the skin. This feature can thus be integrated into the external charger.

p0161The miction via a unidirectional RF data transmission. This allows the patient comfortable and easy operation of the implant. Submitted to the Miktionswunsch and a signal for termination of micturition.

p0162Results

p0163By proper design of the actuator system and a corresponding design of the electronics, it has been achieved, a lightning reaction of the hydraulic system with the low supply voltage of 4.2 V and the complex behavior of the electronics with the low power consumption of less than 0.1 mW in power-down to achieve mode of the microprocessor. The behavior of the implant is such variable so that it can meet a tremendously wide range of requirements.

p0164bibliography

p0165[1] M. Kandler, J. Eichholz, Y. Manoli, W. Mokwa, "CMOS com- patible capacitive pressure sensor with readout electronics", International Conference on Micro Electro, Opto, Mechanic Systems and Components, Microsystem Technologies, pp , 574- 580, 1990

p0166[2] H. Dudaicevs, Y. Manoli, W. Mokwa, M. Schmidt, E. Spiegel, "A Fully Integrated surface micromachined pressure sensor with low temperature dependence", Transducers, Digest of technical papers, pp. 616-619, 1995

p0167[3] H. Wassermann, "Wireless power and signal transmission with simultaneous Disloziervorkehrung and apparatus for inaccessibility one side and opaque dielectric" Technical FB Compendium _r 1992

p0168[4] R. Lerch, E. Spiegel, R. Kakerow, R. Hakenes, H. Cape pert, H. Kohlhaas, N. Kordas, M. Buchmann, T. Franke, Y. Manoli, J. Müller, " A programmable mixed-signal ASIC for data-acquisition system in medical implants ", International Solid-State Circuits Conference, Digest of technical papers, pp. 160-161, 1995

p0169[5] A. Atala, MR Freeman, JP Vacanti, J. Shepard, AB Retik, "in vivo implantation and retrieval of artificial structures Consisting of rabbit and human urothelium and human bladder muscle", J.Urol. 150, pp. 608-612, 1993 [6] D. Jocham and K. Miller "Practice of Urology II", Stuttgart: Georg Thieme, 1994/2002

p0170[7] H. Wassermann, "Artificial harnableitendes System", Medical Supplies in Bavaria, vol. 2, pp. 57-61, 2002

p0171[8] R. Stölting, "Artificial urinary bladder - Clinical tests are pending," medical report, vol 2, pp. 22-23

p0172[9] H. Wassermann, "Artificial Urinary Diversion System", Bavarian Medical Technologies, vol. 2, pp. 53-57, 2002