WO2023003782A1 - Systems and methods for controlling an overactive bladder - Google Patents

Abstract

A system for treating a patient suffering from symptoms of an overactive bladder includes a signal generator, a bladder fullness monitoring apparatus (BFMA), and a controller. When in operation, the signal generator delivers a simulation signal to a peripheral nerve of the patient to stimulate the peripheral nerve and alleviate the patient's overactive bladder symptoms. The BFMA generates a data signal corresponding to a degree of filling of the patient's bladder, and the controller receives the data signal from the BFMA and from the data signal determines a total number of voiding events during one or more monitoring periods. The controller adjusts parameters of the stimulation signal when the determined total number of voiding episodes during the one or more monitoring periods is greater than a target number.

Description

SYSTEMS AND METHODS FOR CONTROLLING AN OYERACTIVE BLADDER

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Application No. 63/223,632 filed July 20, 2021, the disclosure of which is hereby incorporated in its entirety by reference herein.

BACKGROUND

[0002] The present invention relates generally to systems and methods for treating patients suffering from urinary incontinence.

[0003] For example, overactive bladder (OAB) is a form of urinary incontinence characterized by frequent and sudden urges to urinate that may be difficult to control. Many patients feel the need to pass urine many times during the day and night, often causing embarrassment, self-imposed isolation, and limiting the patient’s work and social life. In mild cases, symptoms can often be managed with simple behavioral strategies, such as dietary changes, timed voiding and pelvic floor muscle exercises. If such efforts do not sufficiently relieve overactive bladder symptoms, additional treatments are available, such as medications, and tissue bulking injections in the urinary sphincter. Another option is to use nerve stimulation, where electrical signals are provided to stimulate one or more nerves associated with the bladder and thereby relax the bladder, which may alleviate overactive bladder symptoms. Occasionally after implantation of components of such a nerve stimulation system, reconfiguration of the system may later be required, such as due to changes in physiology or migration of system components. Such reconfiguration is generally performed by a clinician and can be both costly and time- consuming.

[0004] It would be desirable to provide alternative and improved methods and systems to treat urinary incontinence which are effective to adaptively optimize the performance of a previously-implanted nerve stimulation system without the need for clinician intervention.

SUMMARY

[0005] The present invention provides systems for treating a patient suffering from symptoms of urinary incontinence, such as an excessive number of voiding episodes due to OAB. Systems in accordance with the principles of the present invention include a control system including an implantable bladder fullness monitoring apparatus (BFMA), a controller, and a signal generator.

[0006] The BFMA is positioned in a location to sense one or more of a variety of bladder conditions representative of bladder fullness, such as one or more of bladder distention, electrical conductivity of the bladder wall or through the bladder, bladder wall tissue stretch, bladder wall tissue opacity or reflectivity, and bladder weight. The BFMA may be or may include, for example, an integrated circuit (IC), discrete circuitry, or a combination thereof. The BFMA senses the one or more bladder conditions and provides a data signal representative of the bladder conditions and/or representative of a determined bladder fullness, either of which may be referred to herein as a bladder fullness parameter.

[0007] The controller receives the data signal from the BFMA and continuously or periodically monitors the data signal. The controller may aggregate data received from the BFMA over one or more monitoring periods. Examples of aggregated values include number of voiding episodes, volume of residual urine in the bladder after a voiding episode, duration of urination, and so forth.

[0008] The signal generator delivers an electrical signal to a peripheral nerve of the patient to stimulate the peripheral nerve and thereby alleviate the patient’s urinary incontinence symptoms, such as by increasing or decreasing a frequency of voiding episodes, increasing or decreasing a volume held by the bladder between voiding episodes, or increasing or decreasing a duration of voiding episodes. The electrical signal from the signal generator may be referred to herein for convenience as a stimulation signal, which may act to induce a physiological response or block a physiological response.

[0009] The controller provides a control signal to the signal generator to instruct the signal generator as to what the present or future signal delivery parameters of the stimulation signal are or will be. The controller determines the delivery parameters based at least in part on the data signal from the BFMA or the aggregated values determined from the data signal. For example, when an aggregated value falls outside of a target range, or crosses above or below a target threshold, the controller may determine that a modification of the delivery parameters is warranted and may accordingly instruct the signal generator by way of the control signal to modify the stimulation signal in accordance with modified delivery parameters.

[0010] In a particular example of an embodiment of the present invention, a method is provided for treating a patient suffering from symptoms of an overactive bladder which causes an excessive number of patient voiding episodes, where the method includes delivering an electrical stimulation signal from a signal generator of a control system to a peripheral nerve of the patient. The stimulation signal has delivery parameters selected to stimulate the peripheral nerve, where the selection of delivery parameters is chosen to alleviate the patient’s overactive bladder symptoms. The control system autonomously, by way of a controller of the control system: monitors a bladder fullness parameter of the patient’s bladder over a defined monitoring period, where the bladder fullness parameter changes during the monitoring period; identifies characteristics of one or more voiding episodes occurring during the monitoring period based on the monitoring of the bladder fullness parameter; aggregates one or more values associated with the characteristics of the one or more voiding episodes; determines differences between the one or more aggregated values and one or more target goals; and adjusts one or more delivery parameters of the stimulation signal based upon the differences between the aggregated values and the target goals.

[0011] In another particular example of an embodiment of the present invention, a system is provided for treating a patient suffering from symptoms of an overactive bladder. The system includes a signal generator, a BFMA, and a controller. The signal generator is configured to deliver a stimulation signal to a peripheral nerve of the patient, where the stimulation signal has delivery parameters selected to alleviate the patient’s overactive bladder symptoms. The BFMA is configured to generate a data signal corresponding to a degree of filling of the patient's bladder. The controller is configured to receive the data signal from the BFMA and to determine from the data signal a total number of voiding episodes during one or more monitoring periods and is programmed to adjust one or more delivery parameters of the stimulation signal when a determined total number of voiding episodes during the one or more monitoring periods is greater than a first target number.

[0012] For a fuller understanding of the nature and advantages of the present invention, reference should be made to the ensuing detailed description taken in conjunction with the accompanying drawings. The drawings represent embodiments of the present invention by way of illustration. Accordingly, the drawings and descriptions of these embodiments are illustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a block diagram of an example system for treating a patient suffering from symptoms of urinary incontinence in accordance with the principles of the present invention.

[0014] FIG. 2 is a block diagram of an example method for treating a patient suffering from symptoms of urinary incontinence in accordance with the principles of the present invention.

[0015] FIG. 3A shows a use example of a BFMA and a nerve electrode connected to a common enclosure including an implanted controller and signal generator.

[0016] FIG. 3B shows an example of an implant target location for the common enclosure of FIG. 3A or for the controller and/or signal generator if implemented separately.

[0017] FIG. 4 illustrates an example of placement of a BFMA in a surgical pocket between the patient’s pubic bone and the patient’s bladder wall.

DETAILED DESCRIPTION

[0018] Systems in accordance with the principles of the present invention are provided for treating a patient suffering from symptoms of urinary incontinence. In general, such a system is a control system, where the control system includes a signal generator, a BFMA, and a controller. In an embodiment, the control system is implemented as an autonomous closed-loop control system.

[0019] For the avoidance of doubt, the term “in an embodiment” or a variation thereof (e.g., “in another embodiment”, “in a particular example of an embodiment”, or “in one embodiment”) refers herein to use in one or more embodiments, and in no case limits the scope of the present disclosure to only the embodiment as illustrated and/or described. Accordingly, a component or feature illustrated and/or described herein with respect to one embodiment can be omitted or can be used in another embodiment (e.g., in another embodiment illustrated and described herein, or in another embodiment within the scope of the present disclosure and not illustrated and/or not described herein).

[0020] The signal generator delivers an electrical signal to one or more electrodes on or adjacent to a peripheral nerve of the patient to stimulate the peripheral nerve and thereby alleviate the patient’s urinary incontinence symptoms. This electrical signal from the signal generator may be referred to herein as a stimulation signal. The stimulation signal may be selected to cause a physiological response of activation or blocking of signals of afferent or efferent neurons.

[0021] The stimulation signal has one or more specified delivery parameters. For example, the signal generator may be in the form of a pulse generator that delivers approximately square wave signals having delivery parameters such as amplitude, frequency, pulse width, pulse phase, pulse separation, burst pattern, quiescent period, and duty cycle, or the signal generator may be another type of waveform generator that delivers signals in another form, such as, for example, a sawtooth, sine wave, or chirp waveform having delivery parameters such as amplitude, frequency, duty cycle, and quiescent time. The stimulation signal may be direct current (positive values only with respect to an electrical system ground or common level) or alternating current (positive and negative values with respect to an electrical system ground or common level).

[0022] The BFMA generates a data signal corresponding to a degree of filling of the patient's bladder. The data signal may be provided in analog or digital form and may be provided through wired or wireless transmission. An example of wired transmission is by way of one or more conductors, which may be disposed in a sheath to form a lead. An example of wireless transmission is via the Bluetooth® protocol or a proprietary wireless protocol.

[0023] The BFMA may provide the data signal as raw data (e.g., an analog signal representing a sensed force measurement, or a discrete sampled force measurement data value), or as one state of a state machine implemented in the BFMA, or as a summary or aggregated value (e.g., a number representing a duration of a voiding event as determined by the BFMA from raw data), or in any other form suitable for delivery of information to the controller. The data signal can be delivered over a serial data bus or a parallel data bus using a commercially-available protocol or a proprietary protocol.

[0024] The controller receives the data signal from the BFMA and continuously or periodically monitors the data signal.

[0025] The data signal may be provided from the BFMA to the controller by way of a lead extending from the BFMA to a structure containing the controller. Such a structure may also contain the signal generator. In an embodiment, the controller and the signal generator are implemented together in components common to both, such as using one microprocessor with associated memory to implement both the controller and the signal generator. In an embodiment, the controller and the signal generator are implemented in a common enclosure without shared components. In an embodiment, the controller and the signal generator are implemented separately, as separate units.

[0026] The controller and the signal generator are in communication with each other. The controller provides a control signal to the signal generator specifying the delivery parameters for the stimulation signal. The control signal may be in the form of a wired or wireless signal, and instructions sent via the control signal may be in the form of analog or digital signals. In an embodiment, the control signal may be transmitted using a standard or proprietary serial or parallel protocol.

[0027] In an embodiment in which the controller and the signal generator share a memory, the control signal may be in the form of instructions stored in the memory. For example, the controller may store a set of stimulation signal delivery parameters in a shared memory, and may assert a logic “one” on a control line to trigger the signal generator to retrieve the delivery parameters and adjust the stimulation signal according to the delivery parameters. In another example, the controller and the signal generator are implemented as code executed by the same microprocessor, and the controller provides the control signal to the signal generator in the form of a pointer to a portion of a shared memory. Many other electrical system design implementations will be apparent to one skilled in the art, and all such electrical system design implementations are encompassed by the present disclosure.

[0028] The controller receives the data signal from the BFMA and identifies one or more characteristics of a voiding episode or episodes from the data signal. Examples of such characteristics include duration, volume, flow rate, and the like.

[0029] The controller may further determine one or more aggregated values related to the characteristic(s). Alternatively or additionally, the BFMA may provide aggregated values to the controller, and the controller may use the aggregated values without further calculation to determine whether to adjust the stimulation signal delivery parameters, or may perform further calculations on the aggregated values of the data signal from the BFMA to generate additional aggregated values.

[0030] Examples of aggregated values include total number of voiding episodes occurring during one or more monitoring periods, total or average volume of urine expelled during one or more voiding episodes, flow rate of one or more voiding episodes (e.g., total or average flow rate at the beginning of flow and/or total or average flow rate at the end of a set time period after the beginning of flow, or average flow rate across one or more voiding episodes), total or average duration of one or more voiding episodes, total or average volume of residual urine in the bladder after voiding episodes, total or average time between one or more voiding episodes, and so forth. [0031] The controller compares the aggregated value(s) with one or more associated target goal(s) to determine whether the present stimulation signal delivery parameters are achieving a desirable level of effectiveness.

[0032] Table 1 provides examples of target goals (target range or target number) for various examples of aggregated values related to bladder voiding. In this example, the target goal is set by the clinician or the patient using an external programming device, or is set by default. In an embodiment, the target goal is selected as being one of the predefined target range, the predefined widened target range, or the target number. In an embodiment, the target goal is selected as being one of the predefined target range, the predefined widened target range, or the target number, and if the predefined target range or the predefined widened target range is selected, then the target goal may be further refined to be within a subrange of the selected range.

TABLE 1

[0033] The following selection with respect to Table 1, Row 1 is provided by way of an example. An aggregated value reflects the number of voiding episodes, and the controller may adjust the delivery parameters of the stimulation signal to the peripheral nerve when a determined total number of voiding episodes is: (i) greater than the upper limit of 8 if the example target range is selected; (ii) fewer than the lower limit of 6 if the example target range is selected (iii) greater than the upper limit of 12 if the example widened target range is selected; (iv) fewer than 4 if the example widened target range is selected; or (v) greater than the example target number of 6. [0034] In an embodiment, the options for target goal selection by the clinician or patient are not limited to certain ranges or numbers, and the clinician or patient may define their own target goal. In an embodiment, the clinician or patient has a choice between using predefined values or ranges, modifying predefined values or ranges, or creating new values or ranges for the target goals.

[0035] Over time, target goals for a patient may change. The clinician or the patient may change the target goals using an external programming device. The controller may autonomously change the target goals, such as when the patient’s physiology or activity level changes, or such as to start with moderate target goals and over time hone in on more aggressive target goals.

[0036] In addition to providing an ability to be programmed for target goals, the controller can be programmed with a monitoring period or a default monitoring period. The monitoring period duration may change over time, either in a default manner, a programmed manner, or in a manner determined by the controller. [0037] Table 2 provides an example of an embodiment which provides different settings for three different categories of monitoring periods: initial period, interim period, and sustaining period. In this embodiment, for a given category of monitoring period, there are multiple options in Column B (Col. B) from which a clinician or patient can select using an external programming device. If no option is selected, default values will be used by the controller.

TABLE 2

[0038] By way of a first example with respect to Table 2, the clinician and patient may decide to not program specific monitoring period values and instead decide to accept category default values. The controller will accordingly implement the category default monitoring period values starting with an initial period duration of 1 day (Row la-c, Col. D), then after 1 day transition to the category default interim period duration of 1 week (Row 2a-b, Col. D), and then after the 1 week transition to a category default sustaining period duration of 1 month (Row 3a-c, Col. D).

[0039] In an embodiment of the controller programmable according to Table 2, each of the default values for the initial, interim, and sustaining monitoring periods may be stored in a memory at manufacture (e.g., of the memory or of the device containing the controller) and no action is needed from the clinician or patient to select the default value or values. In an embodiment, each of the default values for the initial, interim, and sustaining monitoring periods may be stored in a memory at manufacture (e.g., of the memory or of the device containing the controller) and a confirmation is required from the clinician or patient to use the default value or values.

[0040] In an embodiment of the controller programmable according to Table 2, the clinician or patient can select the initial period, the interim period, and the sustaining period in ter s of hours, days, weeks, or months, as applicable, and accept the associated respective default values.

[0041] By way of a second example with respect to Table 2, the clinician or patient may select the initial period duration in terms of hours (Row la, Col. B), the interim period in term of weeks (Row 2b, Col. B), and the sustaining period in terms of months (Row 3c, Col. B). The controller will accordingly implement the row default monitoring period values starting with an initial period duration of 48 hours (Row la, Col. C), then after 1 day transition to the row default interim period duration of 6 weeks (Row 2b, Col. C), and then after the 6 weeks transition to a row default sustaining period duration of 2 months (Row 3c, Col. C).

[0042] In an embodiment of the controller programmable according to Table 2, the clinician or patient may set the initial period, the interim period, and the sustaining period in terms of specific hours, days, weeks, or months, as desired within the limits set.

[0043] By way of a third example with respect to Table 2, the clinician or patient may select the initial period duration as 8 hours (Row la, value specified), the interim period as 3 weeks (Row 2b, value specified), and the sustaining period as 1 month (Row 3c, value specified). The controller will accordingly implement the row default monitoring period values starting with an initial period duration of 8 hours, then after the 8 hours transition to the interim period of 3 weeks, then after the 3 weeks transition to the sustaining period of 1 month. [0044] In an embodiment of the controller programmable according to Table 2, the clinician or patient may elect to configure one or more of the category or row values and accept default values for the remainder.

[0045] In an embodiment of the controller programmable according to Table 2, the controller may continue to use a monitoring period (initial period, the interim period, or sustaining period, whether specified or default) until a new direction is given to the controller by the clinician or patient.

[0046] The controller can be programmed to self-adjust the monitoring period when particular criteria are met. For example, in the first few days or weeks after the stimulation leads (and optionally the signal generator and/or controller) are implanted, the monitoring period may be set to an initial period by the clinician or patient or by default. Then, when a difference between an aggregated value and a target goal decreases below a threshold value, then the controller can self-adjust the monitoring period to a longer time. Multiple such threshold values may be programmed into the controller so that the controller can self-adjust to a longer monitoring period as the effectiveness of the treatment increases (e.g., as measured by differences between aggregated values and target goals) or shorter if the effectiveness later decreases (e.g., due to movement of implanted components of the system within the body, or due to physiological changes of the patient).

[0047] In an embodiment of the controller programmable according to Table 2, the controller may repeat the initial period, and/or repeat the interim period, as needed until a difference between an aggregated value and a target goal decreases below a specified (by default or by the clinician or patient) progression threshold value associated with the monitoring period. In an embodiment of the controller programmable according to Table 2, the controller may return from the interim period to the initial period, or return from the sustaining period to the interim period or the initial period, if a difference between an aggregated value and a target goal increases above a specified (by default or by the clinician or patient) regression threshold value indicating that more frequent adjustment of the stimulation signal delivery parameters is desirable to revise a stored set of optimal parameters for improved treatment efficacy. The progression and/or regression value may be a single-step value or double step value; for example, a single-step progression threshold may be used to step from the initial period to the interim period or from the interim period to the sustaining period, a double-step progression threshold may be used to step from the initial period to the sustaining period, a single-step regression threshold value may be used to step back from the sustaining period to the interim period or from the interim period to the initial period, or a double-step regression threshold value may be used to step back from the sustaining period to the initial period. [0048] In an embodiment of the controller programmable according to Table 2 implementing progression and/or regression thresholds, the clinician or patient may program progression and/or regression thresholds or may elect to use defaults.

[0049] In an embodiment of the controller programmable according to Table 2 implementing progression and/or regression thresholds, the clinician or patient may program whether or not to use the progression and/or regression thresholds, or to limit to single-step thresholds.

[0050] In general, whether there is one category of monitoring period or several (e.g., 2-10 categories of monitoring periods), the controller determines aggregated values from the data signal from the BFMA, compares the aggregated values to target goals, determines whether to adjust the stimulation signal, and determines whether to adjust the duration of the monitoring period.

[0051] Based on the determined aggregated values, the controller controls the signal generator to provide the stimulation signal to the target nerve.

[0052] The controller can be programmed in a variety of ways to adjust the stimulation signal in response to changes in the aggregated values detected over time. For example, delivery parameters of the stimulation signal such as amplitude, frequency, pulse width, pulse phase, pulse separation, burst pattern, quiescent period, and/or duty cycle can be incrementally increased or decreased. The parameters may be adjusted individually, so that the controller can identify a sensitivity of the patient’s physiology to each change in an individual parameter. The parameters may be adjusted for coarse identification of an acceptable treatment configuration, and then finely adjusted until a more optimal treatment configuration has been achieved. For example, an individual parameter may be adjusted in large steps to find an acceptable treatment setting for that parameter, then adjusted in small steps to find an improved or optimal treatment setting for that parameter. As an improved or optimal setting for one delivery parameter is found, the search for an improved or optimal setting for another delivery parameter may begin, so the adjustment continues over time as the controller continues to seek an optimal configuration of all parameters. The controller may adjust the delivery parameters in a sequence, such as round-robin switching between the delivery parameters to adjust each in turn, or randomly switching between the delivery parameters. [0053] The controller may also be programmed to identify correlations between how the body reacts to changes in different parameters. The controller may use the correlations to adjust two or more parameters together to find an acceptable treatment configuration, then adjust individual parameters to find an improved or optimal treatment configuration. Or, the controller may use the correlations to adjust two or more parameters together to find an improved or optimal treatment configuration.

[0054] FIG. 1 schematically illustrates an embodiment of a control system 100 for treating a patient suffering from symptoms of urinary incontinence. The control system 100 includes a BFMA 110, a controller 120, a signal generator 130, and at least one electrode 140.

[0055] The BFMA 110 is coupled to a patient’s bladder and is configured to determine a bladder fullness parameter. The BFMA 110 may be implemented as a single apparatus to determine a single bladder fullness parameter, a single apparatus to determine multiple bladder fullness parameters, or two or more apparatuses to determine multiple bladder fullness parameters. The BFMA 110 may be an active or passive device (or if multiple apparatuses, one or more may be passive devices and/or one or more may be active devices), where active device refers to a device which is capable of providing an electrical signal without external intervention, and passive device refers to a device which may be read by applying a voltage or current to the passive device from an external source.

[0056] The controller 120 is connected to receive a data signal 115 from the BFMA 110 which is representative of the bladder fullness parameter. The controller 120 is further connected to the signal generator 130. The controller 120 is programmed to control the signal generator 130 to deliver a stimulation signal 135 to a target peripheral nerve through the electrode 140. The controller 120 may be in the form of one or more integrated circuits, or discrete circuitry, or a combination of integrated circuits and discrete circuitry. The controller 120 will receive the data signal 115 from the BFMA 110 representative of the bladder fullness parameter and aggregate a bladder fullness value which may then be compared with a target bladder fullness goal. The controller 120 may then control the signal generator 130 (via a control signal 125) to adjust the stimulation signal 135 in a manner estimated to improve a patient outcome. For example, if the controller 120 determines that a number of patient voiding episodes in a monitoring period exceeds an expected number or range of voiding episodes, the controller 120 can send instructions via the control signal 125 to the signal generator 130 to adjust the stimulation signal 135 in a manner intended to improve the treatment.

[0057] The signal generator 130, under the control of the controller 120, outputs the stimulation signal 135 to the electrode(s) 140. The signal generator 130 provides the stimulation signal 135 to the electrode 140 to stimulate a target nerve which affects bladder function, such as by causing the bladder to relax or contract. The target nerve may be, for example, a sacral nerve, a pudendal nerve, or a tibial nerve, to deliver signals by way of the sacral nerve plexus SNP.

[0058] The control system 100 interacts with the body of a patient 150. The BFMA 110 is positioned and connected within the body of the patient 150 so as to sense one or more of a variety of bladder conditions 160 representative of bladder fullness in determining the bladder fullness parameter, such as one or more of bladder distention, electrical conductivity of the bladder wall or through the bladder, bladder wall tissue stretch, bladder wall tissue opacity or reflectivity, and bladder weight. A particular system for measuring bladder weight in real time is described in more detail below with respect to FIG. 3 A, FIG. 3B, and FIG. 4, by way of example. Additionally, the electrode 140 is positioned adjacent to, or around (e.g., a cuff electrode), a target nerve of the patient 150.

[0059] The electrode 140 is sufficiently in the proximity of the target nerve to deliver electrical energy 170 to the target nerve such that the target nerve causes relaxation or contraction of the bladder, as applicable for the electrical energy 170 provided. The electrical energy 170 delivered from the electrode 140 to the target nerve will depend on several factors, including the delivery parameters of the stimulation signal 135, the proximity of the electrode 140 to the target nerve, the physical structure of the electrode 140, the impedance of the target nerve, leakage currents, and electromagnetic interferences. In other words, when the electrical energy 170 is applied to the nerve by the electrode 140, portions of the body become the circuit load for the circuit that includes the electrode 140, and the circuit load impacts the parameters of the delivered electrical energy 170.

[0060] The controller 120 and the signal generator 130 may be implemented within a single enclosure, or may be implemented separately in different enclosures. The controller 120 enclosure and/or the signal generator 130 enclosure (or if applicable the single enclosure containing both) may be implanted in the patient 150.

[0061] In embodiments in which the controller 120 and the signal generator 130 are implemented within the same enclosure, the controller 120 and the signal generator 130 may further be implemented using components common to both, such as both implemented using a single microprocessor and shared memory, among other shared components.

[0062] The control signal 125 may be in the form of a wired or wireless signal, and instructions sent via the control signal 125 may be in the form of analog or digital signals, and in an embodiment may be transmitted using a standard or proprietary serial or parallel protocol. In embodiments in which the controller 120 and the signal generator 130 share a memory, the control signal 125 may be in the form of instructions stored in the memory.

For example, the controller 120 may store a set of delivery parameters for the stimulation signal 135 in a shared memory, and may assert a logic “one” on a control line to trigger the signal generator 130 to retrieve the stimulation signal 135 delivery parameters and adjust the stimulation signal 135 according to the delivery parameters. In another example, the controller 120 and the signal generator 130 are both at least partially implemented as code in the same microprocessor, and the code for the controller 120 provides the control signal 125 to the code for the signal generator 130 in the form of a pointer to a portion of a shared memory. Many other electrical system design implementations will be apparent to one skilled in the art, and all such electrical system design implementations are encompassed by the present disclosure.

[0063] The control system 100 provides for autonomous closed-loop control, when the control system 100 is connected in a manner such that the BFMA 110 is able to sense bladder conditions 160 of the patient 150 and electrode 140 is able to provide electrical energy 170 to the target nerve of the patient 150 in a manner effective to cause expected physiological actions to occur. In operational closed-loop mode, the control system 100 performs at least the following functions: (a) the BFMA 110 senses bladder conditions 160, (b) the controller 120 receives the data signal 115 from the BFMA 110 representative of the bladder conditions 160, (c) the controller 120 aggregates bladder fullness values, (d) the controller 120 compares the aggregated values to target goals, (e) the controller 120 provides the control signal 125 to the signal generator 130 to either maintain or modify delivery parameters of the stimulation signal 135, (f) the signal generator 130 maintains or modifies delivery parameters of the stimulation signal 135 as instructed by the control signal 125 and provides the stimulation signal 135 to the electrode 140, and (g) the electrode 140 delivers electrical energy 170 to the target nerve as applicable.

[0064] Although FIG. 1 illustrates the data signal 115 and the control signal 125 for convenience by way of unidirectional arrows, it is to be understood that the BFMA 110 and the controller 120 may communicate unidirectionally or bidirectionally to exchange a variety of information including the data signal 115, and the controller 120 and the signal generator 130 may communicate unidirectionally or bidirectionally to exchange a variety of information including the control signal 125. Further, the stimulation signal 135 and the electrode 140 may form a closed circuit in combination with the signal generator 130 such that current is delivered from the signal generator 130 to the electrode 140 and returned from the electrode 140 to the signal generator 130. Additionally, the control system may include communication channels between the components that are not shown in FIG. 1. Moreover, the control system 100 may include numerous additional components and functionality not shown, such as one or more power supplies (which may be wirelessly rechargeable), one or more wireless communication interfaces, one or more memories, one or more output drivers, protection circuitry, and so forth.

[0065] As discussed above, the controller 120 is configured to receive the data signal 115 from the BFMA 110 and to process the data signal 115 to detect voiding episodes and determine specific characteristics of each voiding episode, such as duration, volume, flow rate, and the like, to determine aggregated values (see, e.g., the examples in Table 1) and, based on the determined characteristics and/or aggregated values, provide a control signal 125 to the signal generator 130 instructing the signal generator 130 to provide a stimulation signal 135 having delivery parameters in accordance with such instructions.

[0066] FIG. 2 illustrates an embodiment of a treatment methodology 200 for treating urinary incontinence. The methodology 200 is coded into instructions (e.g., hard coded in circuitry, coded in firmware, and/or coded in software) for execution by the controller 120 to perform the aforesaid tasks of the controller 120 according to an embodiment. The methodology 200 is discussed with reference to components illustrated and described with respect to FIG. 1 for convenience without limitation.

[0067] At 210, the controller 120 receives the data signal 115 from the BFMA 110.

[0068] At 220, the controller 120 detects a voiding episode and determines characteristics related to the voiding episode based on the data signal 115.

[0069] At 230, based on these determined characteristics, the controller can calculate aggregated values which are associated with a particular voiding episode or a series of voiding episodes. Such aggregated values are compared with target goals which may be fixed values stored in a memory in or associated with the controller or variable values which are updated from time to time by the controller.

[0070] At 240, the controller 120 determines a difference AV between an aggregated value and a target goal, or determines differences AV between multiple aggregated values and their associated target goals.

[0071] In general, there are three outcomes which can come about based on the comparison of an aggregated value and a target goal. First, a difference between the target goal and the aggravated value may indicate that the present delivery parameters are insufficient and need to be adjusted. For example, in the case where the number of voiding episodes in one or more monitoring periods exceeds a maximum threshold for the number of voiding episodes, indicating that the patient is urinating too frequently, delivery parameters of the stimulation signal can be adjusted in a manner expected to increase suppression of the bladder function (e.g. the amplitude of the control signal could be increased or decreased) to decrease urination frequency. Second, the aggravated value may fall within an expected range of the target goals or fall below the maximum threshold, in which case the controller may determine that no adjustment or change to the delivery parameters is needed. Third, the difference between the target goal and the aggregated value may indicate that the treatment is overly effective, for example the number of voiding episodes falls below a minimum threshold or below a range such that the patient is urinating too infrequently, in which case the signal parameters may be adjusted in a manner expected to reduce the suppression of the bladder function to increase urination frequency.

[0072] At 250, if the difference(s) AV indicate that the treatment provided by way of the present delivery parameters of the stimulation signal 135 is insufficient to reach the target goals for the treatment, the controller 120 (at 255) selects a revised set of parameters for the stimulation signal 135 and instructs the signal generator 130 by way of the control signal 125 to modify the stimulation signal 135 with the revised delivery parameters. [0073] Alternatively, at 260, if the difference(s) AV indicate that the treatment provided by way of the present delivery parameters of the stimulation signal 135 is presently sufficient to reach the target goals for the treatment (e.g., AV is within an expected range or below a threshold value), the controller 120 (at 265) instructs the signal generator 130 by way of the control signal 125 to continue to provide the stimulation signal 135 with the present delivery parameters, or the controller 120 does not provide a new control signal 125 to the signal generator 130 such that the signal generator 130 continues to provide the stimulation signal 135 with the present delivery parameters.

[0074] Alternatively, at 270, if the difference(s) AV indicate that the treatment provided by way of the present delivery parameters of the stimulation signal 135 is overly effective to reach the target goals for the treatment (e.g., the patient 150 is not urinating frequently enough or a bladder fullness has exceeded a threshold between voiding episodes), the controller 120 (at 275) selects a revised set of delivery parameters for the stimulation signal 135 and instructs the signal generator 130 by way of the control signal 125 to modify the stimulation signal 135 with the revised delivery parameters.

[0075] The controller may determine the desired delivery parameters based on a combination of aggregated values calculated from two or more parameters of the data signal from the BFMA. For example, the controller may consider the number of voiding episodes along with the duration of voiding episodes, or the volume of voiding episodes with the flow rate of voiding episodes, or other combinations of parameters (e.g., combinations of two or more of the parameters in Table 1) in determining the signal to be applied by the signal generator.

[0076] FIG. 3 A depicts an example system illustrating one possible placement of various components of a control system within a female patient’s body for an embodiment in which a nerve or nerve bundle of the sacral nerve plexus is intended to be stimulated. The body is shown in cutaway side view and indicates the approximate location of the bladder B within the pelvic cavity and in relation to the spine S. In this embodiment, the controller and signal generator are housed together in a common enclosure 310. The enclosure 310 is electrically connected to an electrode 320 or set of electrodes 320 by a lead 325 (or multiple leads 325 as applicable), and is connected to a BFMA 330 by a lead 335. The enclosure 310 (or the controller and/or the signal generator individually in other embodiments) will typically be implanted in a tissue area near the stimulation site to reduce a length of the lead(s) 325, such as in tissue beneath the skin of the buttocks and with access to the appropriate nerve. In the embodiment illustrated in FIG. 3 A, the enclosure 310 is positioned in fatty tissue somewhere in the region of the buttocks, the lead 325 is routed through one of the sacral foramen (e.g., through the SI, S2, S3, or S4 sacral foramen), the electrode(s) 320 are positioned adjacent a sacral nerve, the BFMA 330 is positioned between the bladder B and the pubic bone B of the patient, and the lead 335 is tunneled to the BFMA 330 as surgically possible and appropriate.

[0077] The lead 325 will typically contain two or more conductors (e.g., wires) to provide the stimulation signal to the electrode(s) 320. In an embodiment, the electrode 320 is a bipolar or bipolar electrode 320 to focus the electrical energy on a smaller volume of the nerve than would be possible with a unipolar electrode 320, to minimize or prevent unintended nerve excitation. Electrodes 320 may be positioned along the lead 325 and placed adjacent the target nerve, or may be positioned within a cuff that is placed over the nerve. In an embodiment, multiple leads 325 provide signals from the signal generator to electrodes 320 positioned on or at different nerves or at different locations along a same nerve.

[0078] The BFMA 330 may be positioned in a pocket created by the surgeon in fascia or other connective tissue adjacent the pubic bone PB.

[0079] Once the BFMA 330 is positioned at a selected location in tissue between the patient's pubic bone PB and bladder B and is coupled to a controller (e.g., in the enclosure 310), the BFMA 330 delivers to the controller data signals corresponding to bladder fullness parameters. Coupling may either be directly by a lead 335, as illustrated, or may be achieved wirelessly (e.g., using an RF transmitter or other transmission means).

[0080] Referring to FIG. 3B, a drawing is provided of a skeletal pelvic portion of a body including the pelvic girdle, a portion of the spinal column, and a portion of the hip and leg bones. FIG. 3B provides further context for the embodiment of FIG. 3 A. As indicated in FIG. 3 A in combination with FIG. 3B, the bladder B sits near the pubic bone PB within the pelvic girdle. The enclosure 310 is positioned in a buttocks area posterior to the pelvic girdle. The nervous system includes nerve bundles that extend through the spine and exit the spine at various points along the spine, including at the foramina of the sacrum. Various nerve branches occur adjacent to different ones of the sacral foramina. Therefore, lead 325 can be threaded through a foramen of the sacrum (SI, S2, S3, or S4 foramen; S3 is noted in FIG. 3B for reference) and positioned adjacent a target nerve or nerve bundle. In an embodiment having multiple leads 325 each of which provides stimulation to different nerves or nerve bundles or to different portions of a nerve, the multiple leads 325 may be threaded through a single foramen or through different foramina. The selection of the appropriate foramen depends in part on the particular nerve or nerve bundle the electrode(s) 320 are intended to stimulate, and the location of that particular nerve or nerve bundle relative to the various foramina.

[0081] The lead 335 may be similarly threaded through a foramen, or may alternatively be routed under/around the pelvic girdle to the bladder B.

[0082] FIG. 4 illustrates an embodiment of the BFMA 330 that includes a base 420 formed of a flexible material, a rigid layer 430 attached to the base 420, a pressure sensor 440 positioned on the rigid layer 430, and a deformable membrane 450 positioned over and hermetically sealed to the rigid layer 430. By way of example, a surgeon may create a pocket within tissue between the bladder B and the pubic bone PB, slide the BFMA 330 into the pocket, and suture the base 420 of the BFMA 330 to any tissue between the bladder B and the pubic bone PB that can hold the BFMA 330 in its position relative to the pubic bone PB. The base 420 is configured to be attached (e.g., via suturing) to tissue between the pubic bone PB and the bladder B. The base 420 may be configured to be positioned near the patient's pubic bone PB such that mechanical support provided by the pubic bone PB to the base 420 prevents the membrane 450 from being substantially deformed by force from tissue other than the bladder B. As used herein the term “substantially deform” means deformation in one or more dimensions of the membrane 450 of more than about 10%, more preferentially, more than about 5%. The base 420 may specifically be configured to conform to a contour C of the pubic bone PB so as to be mechanically supported by the public bone PB. A shape of the base 420 from a bottom view may be circular, square, hexagonal, or other regular shape, or an irregular shape. A diameter or longest dimension of the base 420 in an embodiment is in a range from about 1.5 centimeters (cm) to about 3.0 cm with larger and smaller dimensions contemplated. The shape and dimensions of the base 420 can be configured to place the base 420 at a desired location including being positioned against a section of the pubic bone PB facing towards the patient's bladder B.

[0083] In the embodiment of FIG. 4, the sensor 440 is positioned on a portion of the rigid layer 430 within a cavity 435 such that it is able to measure the pressure of the fluid within the cavity 435. The sensor 440 is configured to generate a signal (analog or digital electrical signal) representing the pressure within the cavity 435 which is in turn correlated to a degree of fullness of the bladder, which signal is transmitted to the controller by a physical conductor (e.g., lead 335) or wirelessly. The sensor 440 may be attached to the rigid layer 430 via an adhesive and may be electrically coupled to circuitry on the rigid layer 430 (as applicable) by solder or other electrically conductive means. According to various embodiments, the sensor 440 may correspond to one or more of a strain gauge, a solid-state sensor, or a MEMS-based sensor. In specific embodiments, the strain gauge may correspond to a Wheatstone bridge circuit. The sensor 440 may be constituted by two or more individual sensors 440, positioned in one or more locations within the cavity 435. Use of multiple sensors 440 provides the benefit of a more uniform measurement of pressure within the cavity 435 to account for any differences in pressure within the cavity 435 as well as providing redundancy should any individual sensor 440 malfunction or cease operation after implantation.

[0084] In an embodiment, the controller, the signal generator, and/or the BFMA are reprogrammable, by way of a wireless communication interface. In an embodiment, the controller, the signal generator, and/or the BFMA are rechargeable, by way of a wireless recharging interface.

[0085] In an embodiment, the control system 100 further includes one or more sensors to detect motion and/or position of the patient, and the controller 120 receives information from the sensor(s) related to motion and/or position and adjusts the control signal 125 to the signal generator 130, or adjusts the algorithm for determining the control signal 125, to compensate for the patient’s motion and/or position. For example, the controller 120 may receive information from a sensor indicating that the patient is running (e.g., the sensor provides the information that the patient is running, or the controller 120 determines that the patient is running based on information provided by the sensor) and may adjust the algorithm by switching to averaging bladder fullness measurements over longer time periods to compensate for the bouncing and sloshing of the bladder. For another example, the controller 120 may receive information from a sensor indicating that the patient is reclining and may adjust a bladder fullness parameter to compensate for the position (e.g., such as by adjusting the bladder fullness parameter upwards to compensate for a change in the direction of the force of gravity if the BFMA is placed between the bladder and the pubic bone and measures force of the bladder against a sensor, or adjusting downwards to compensate for a relocation of urine in the bladder if the BFMA is located on the side of the bladder presently facing up and measures bladder distension by bladder opacity). For a further example, the controller 120 may receive information from a sensor indicating that the patient is rising from a sitting position towards a standing position, and may adjust the control signal 125 to known effective parameters for relaxing the bladder and/or contracting a urinary sphincter to prevent leakage due to the sudden motion.

[0086] Thus has been described examples of systems and methods for alleviating symptoms of urinary incontinence such as OAB in accordance with the invention. Further examples follow. These examples are instructive and do not limit the scope of the present invention.

[0087] In an embodiment, a method is provided for treating a patient suffering from symptoms of OAB which causes an excessive number of patient voiding episodes, where the method includes delivering an electrical stimulation signal from a signal generator of a control system to a peripheral nerve of the patient. The stimulation signal has delivery parameters (such as described above) selected to stimulate the peripheral nerve, where the selection of delivery parameters is chosen to alleviate the patient’s OAB symptoms. The control system autonomously, by way of a controller of the control system: monitors a bladder fullness parameter of the patient’s bladder over a defined monitoring period, where the bladder fullness parameter changes during the monitoring period; identifies characteristics of one or more voiding episodes occurring during the monitoring period based on the monitoring of the bladder fullness parameter; aggregates one or more values associated with the characteristics of the one or more voiding episodes; determines differences between the one or more aggregated values and one or more target goals; and adjusts one or more delivery parameters of the stimulation signal based upon the differences between the aggregated values and the target goals.

[0088] The method may further include any one of, or any combination of, the following features, or any other feature or element described hereinabove (alone or combination with one or more of the following features or other elements or features described hereinabove):

[0089] An aggregated value may be a totalized value, such as a summation of detected or measured parameter values or events, for example the number of voiding episodes, the total residual volume of urine in the bladder after each voiding episode, the total time of voiding during the monitoring period, or the like. An aggregated value may be an averaged value, such as any of the summations above divided by the number of changes or events detected.

[0090] Aggregating may include counting the number of voiding episodes during the monitoring period, where the target goal is an expected number of voiding episodes for the patient during the monitoring period. A voiding episode may be detected and counted, for example, when the BFMA measures a loss in urine of a magnitude (typically at least 50 milliliters (ml), usually at least 100 ml, often at least 150 ml) and optionally for a duration (typically at least 5 seconds (sec), usually at least 10 sec, often at least 30 sec) which indicates that the patient has intentionally or unintentionally voided urine from the bladder. Target goals (values or ranges) for the number of voiding events may be, for example, 4/day to 12/day, 5/day to 10/day, or 6/day to 8/day. Further criteria can be applied. For example, an additional or alternative target goal for the number of voiding events can be set for overnight periods (when the patient is trying to sleep), such as no more than once per night. When the number of patient voiding events exceeds the target goal, one or more delivery parameters of the stimulation signal can be adjusted to adjust the stimulation of the peripheral nerve to further alleviate the patient’s OAB symptoms.

[0091] Counting voiding episodes is performed in a counter of the control system, where the target goal is a number or range, such as 6 to 8 voiding episodes per day or 1 to 2 voiding episodes per night.

[0092] At least some of the target goals may be fixed and will not change during or between monitoring periods. For example, a target goal of 6 to 8 voiding episodes per day may be set and remain constant for many or most patients although some patients may change the target goal based upon personal preference. Alternatively, at least some of the target goals may be adjustable values that may be updated during or between monitoring periods. For example, a target goal for the total number of voiding events per day might be autonomously adjusted upward or downward by the controller based upon the number of voiding events experienced by the patient overnight. In general: one or more of the target goals may be autonomously adjusted by the controller; one or more of the target goals may be fixed and not autonomously adjusted by the controller; and one or more of the target goals may be adjusted by the patient and/or treating professional.

[0093] A target goal may be based on a counter value from an immediately prior monitoring period or may be based on an average or median of counter values from two or more prior monitoring periods. [0094] Aggregating may include determining a total or averaged bladder fullness volume after voiding episodes during the monitoring period where the associated target goal is a total or averaged bladder fullness volume expected for the patient after a voiding episode. Alternatively or additionally, aggregating may involve totalizing or averaging the duration of the voiding episodes during the monitoring period where the associated target goal is a total or average duration, respectively, of voiding episodes expected for the patient.

[0095] A target goal may be a range with upper and lower limits, where a difference between the aggregated value and the target goal is determined with reference to the upper and lower limits. That is, the aggregated value is considered acceptable or normal so long as it falls in the range, and no adjustment of the delivery parameters of the stimulation signal will be performed.

[0096] To maintain a record of patient voiding episodes and system performance over time, the controller may autonomously store information during and/or at the end of at least some of the monitoring periods (e.g., at the end of each monitoring period). Such stored information may include the aggregated values, the target values, and/or one or more of the differences between aggregated values and target values. Such stored information may further include a code identifying the associated monitoring period. A code may include, for example, one or more of start time and end time of the monitoring period, duration of the monitoring period, sequence number of the monitoring period for embodiments in which sequential monitoring periods are predefined, whether the monitoring period was a daytime or nighttime period, which of multiple daytime or nighttime periods the monitoring period was, and so forth. The stored information may form a chronological and/or time record in a memory of the control system. For example, the controller may autonomously store delivery parameters applied during a monitoring period in the memory at the end of each monitoring period. Alternatively or additionally, the controller may autonomously store information according to delivery parameters or target goals or aggregated values.

[0097] Monitoring the bladder fullness parameter may include continuously monitoring the bladder fullness parameter during at least some of the monitoring periods.

[0098] Monitoring the bladder fullness parameter may include periodically monitoring the bladder fullness parameter during at least some of the monitoring periods.

[0099] The controller may autonomously suspend adjusting the one or more delivery parameters of the stimulation signal for a predetermined time period when a difference between an aggregated value and a target goal falls below a maximum threshold level for a minimum time period. Alternatively or additionally, at such occurrence, the controller may autonomously store an optimum set of stimulation signal delivery parameters equal to a present set of delivery parameters. Often, such an optimum set of delivery parameters is not changed for a predetermined time after the optimum set of delivery parameters has been stored.

[0100] The controller may autonomously receive the bladder fullness parameter from a BFMA, determine a number, volume, and/or duration of voiding episodes, and adjust the one or more delivery parameters. For example, the controller may be programmed to (a) iteratively adjust a selected individual stimulation signal delivery parameter, (b) determine whether observed results are positively affected, unaffected, or negatively affected, (c) further iterate the selected individual delivery parameter to a new value if the observed results are positively affected, and (d) return the selected individual delivery parameter to its prior value if the observed results are unaffected or negatively affected.

[0101] The control system may further include an implanted BFMA located between the patient's pubic bone and the patient’s bladder, and the BFMA provides a data signal to the controller corresponding to a weight of urine in the bladder. [0102] The control system may further include one or more sensors to detect motion and/or position of the patient, and the controller receives information from the sensor(s) related to motion and/or position and adjusts the control signal to the signal generator, or adjusts the algorithm for determining the control signal, to compensate for the patient’s motion and/or position.

[0103] In an embodiment, a system is provided for treating a patient suffering from symptoms of OAB. The system includes a signal generator, a BFMA, and a controller. The signal generator is configured to deliver stimulation signal to a peripheral nerve of the patient, where the stimulation signal has delivery parameters (such as described above) selected to alleviate the patient’s OAB symptoms. The BFMA is configured to generate a data signal corresponding to a degree of filling of the patient's bladder. The controller is configured to receive the data signal from the BFMA and to determine from the data signal a total number of voiding episodes during one or more monitoring periods and is programmed to adjust one or more delivery parameters of the stimulation signal when a determined total number of voiding episodes during the one or more monitoring periods is greater than a first target number.

[0104] The system may further include any one of, or any combination of, the following features, or any other feature or element described hereinabove (alone or combination with one or more of the following features or other elements or features described hereinabove):

[0105] The controller may be further programmed to adjust one or more delivery parameters when a determined total number of voiding episodes during the one or more monitoring periods is less than a second target number.

[0106] The signal generator and the controller may both be implantable. Alternatively, the signal generator may be implantable and all or a portion of the controller may be external to the patient. In an embodiment, such as for initial trials to test the suitability of the system for the patient, both the signal generator and the controller may be external to the patient.

[0107] The controller may be programmed to set a counter to zero at the beginning of a first monitoring period, determine from the data signal from the BFMA when a voiding episode has occurred, and increment the counter at each determined voiding episode to determine the total number of voiding episodes during the one or more monitoring periods. Such a counting cycle may be repeated through multiple subsequent monitoring periods.

[0108] The controller may be further programmed to (a) iteratively adjust a selected individual stimulation signal delivery parameter, (b) determine whether observed results are positively affected, unaffected, or negatively affected, (c) further iterate the selected individual delivery parameter to a new value if the observed results are positively affected, and (d) return the selected individual delivery parameter to its prior value if the observed results are unaffected or negatively affected. [0109] The BFMA may be configured to be located between the patient's pubic bone and the patient’s bladder and the signal corresponds an amount of distension of the patient's bladder resulting from a weight of urine in the bladder.

[0110] The control system may further include one or more sensors to detect motion and/or position of the patient, and the controller receives information from the sensor(s) related to motion and/or position and adjusts the control signal to the signal generator, or adjusts the algorithm for determining the control signal, to compensate for the patient’s motion and/or position.

[0111] The foregoing description of various embodiments of the invention has been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed. Many modifications, variations and refinements of the embodiments described herein will be apparent to practitioners skilled in the art including for example those skilled in the medical implant, sensor, neuro-stimulation and urinary device arts. For example, systems and components may be adapted for the urinary tracts of both male and female patients. For another example, systems and components may be adapted to treat fecal incontinence. Further, those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific devices and methods described herein. Such equivalents are considered to be within the scope of the present invention and are covered by the appended claims below.

[0112] With regard to the drawings, it is to be understood the drawings are not necessarily drawn to scale. There may also be distinctions between the artistic renditions shown in the drawings and the actual apparatus due to drawing perspective, the drawings not necessarily being to scale, size constraints, manufacturing considerations and other factors. Also, there are multiple embodiments and/or elements of the embodiments which are not necessarily shown in the drawings which are nonetheless contemplated by the present disclosure.

[0113] Further, any element, characteristic, constituent, feature, step etc. from one embodiment can be readily recombined or substituted with one or more element, characteristic, constituent, feature, step etc. from other embodiments to form numerous additional embodiments within the scope of the invention. Moreover, elements that are shown or described as being combined with other elements, can, in various embodiments, exist as standalone elements. Also, for any positive recitation of an element, characteristic, constituent, feature, step etc., embodiments of the invention specifically contemplate the exclusion of that element, characteristic, constituent, feature, step, etc. Hence, the scope of the present invention is not limited to the specifics of the described embodiments, examples and drawings, but is instead limited solely by the appended claims.

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A method for treating a patient suffering from symptoms of an overactive bladder which causes an excessive number of patient voiding episodes, said method comprising: delivering an electrical stimulation signal from a signal generator of a control system to a peripheral nerve of the patient, wherein the stimulation signal has delivery parameters selected to stimulate the peripheral nerve, the selection of delivery parameters chosen to alleviate the patient’s overactive bladder symptoms, wherein the control system autonomously, by a controller of the control system: monitors a bladder fullness parameter of the patient’s bladder over a defined monitoring period, wherein the bladder fullness parameter changes during the monitoring period; identifies characteristics of one or more voiding episodes occurring during the monitoring period based on the monitoring of the bladder fullness parameter; aggregates one or more values associated with the characteristics of the one or more voiding episodes; determines differences between the one or more aggregated values and one or more target goals; and adjusts one or more delivery parameters of the stimulation signal based upon the differences between the aggregated values and the target goals.

2. The method of claim 1 wherein the aggregated value is a totalized value.

3. The method of claim 1 wherein the aggregated value is an averaged value.

4. The method of any of claim 1 to claim 3 wherein aggregating comprises counting the number of voiding episodes during the monitoring period and the target goal comprises an expected number of voiding episodes for the patient during the monitoring period.

5. The method of any of claim 1 to claim 4 wherein aggregating comprises determining a bladder fullness volume after voiding episodes during the monitoring period and the target goal comprises a bladder fullness volume expected for the patient after a voiding episode.

6. The method of any of claim 1 to claim 5 wherein aggregating comprises determining the duration of the voiding episodes during the monitoring period and the target goal comprises a duration of voiding episodes expected for the patient.

7. The method of any of claim 1 to claim 6 wherein the target goals comprise ranges with upper and lower limits, and wherein differences between the aggregated values and the target goals are determined with reference to the upper and lower limits.

8. The method of any of claim 1 to claim 7, wherein at least one of the target goals is an adjustable value that may be updated during or between monitoring periods.

9. The method of any of claim 1 to claim 8, further comprising the controller autonomously storing in a memory of the control system at the end of each monitoring period the aggregated values determined during the monitoring period and a code identifying the monitoring period.

10. The method of claim 9, further comprising the controller autonomously storing delivery parameters from each monitoring period in the memory at the end of said monitoring period.

11. The method of any of claim 1 to claim 10, wherein monitoring the bladder fullness parameter comprises continuously monitoring the bladder fullness parameter during at least some of the monitoring periods.

12. The method of any of claim 1 to claim 11, wherein monitoring the bladder fullness parameter comprises periodically monitoring the bladder fullness parameter during at least some of the monitoring periods.

13. The method of any of claim 1 to claim 12, wherein the stimulation signal comprises a pulse pattern having one or more delivery parameters selected from a group consisting of amplitude, frequency, pulse width, pulse phase, pulse separation, burst pattern, quiescent period, and duty cycle.

14. The method of any of claim 1 to claim 13, wherein the stimulation signal comprises a waveform having one or more delivery parameters selected from a group consisting of amplitude, frequency, duty cycle, and quiescent time.

15. The method of any of claim 1 to claim 14, wherein aggregating one or more values associated with each voiding episode comprises counting voiding episodes in a counter of the control system, wherein the target goal is a target number.

16. The method of claim 15, wherein the target number is fixed.

17. The method of claim 16, wherein the target number is based on a counter value from an immediately prior monitoring period.

18. The method of claim 16, wherein the target number is based on an average or median of counter values from two or more prior monitoring periods.

19. The method of any of claim 1 to claim 18, wherein the controller autonomously suspends adjusting delivery parameters of the stimulation signal for a predetermined time period when selected differences between the aggregated values and the target goals fall below threshold levels for a defined time period.

20. The method of any of claim 1 to claim 19, wherein the controller autonomously stores an optimum set of stimulation signal delivery parameters equal to a present set of delivery parameters when selected differences between the aggregated values and the target goals fall below threshold levels for a defined time period.

21. The method of claim 20, wherein the optimum set of delivery parameters is not changed for a predetermined time after the optimum set of delivery parameters have been stored.

22. The method of any of claim 1 to claim 21, wherein the controller which autonomously receives the bladder fullness parameter from a bladder fullness monitoring apparatus (BFMA), determines a number, volume, and/or duration of voiding episodes, and adjusts one or more of the delivery parameters.

23. The method of claim 22, wherein the controller is programmed to (a) iteratively adjust a selected individual stimulation signal delivery parameter, (b) determine whether observed results are positively affected, unaffected, or negatively affected, (c) further iterate the selected individual delivery parameter to a new value if the observed results are positively affected, and (d) return the selected individual delivery parameter to its prior value if the observed results are unaffected or negatively affected.

24. The method of claim 23, wherein the BFMA is configured to be located between the patient's pubic bone and the patient’s bladder, and the BFMA provides a data signal to the controller corresponding to a weight of urine in the bladder.

25. A system for treating a patient suffering from symptoms of an overactive bladder, said system comprising: a signal generator configured to deliver a stimulation signal to a peripheral nerve of the patient, wherein the stimulation signal has delivery parameters selected to alleviate the patient’s overactive bladder symptoms; a bladder fullness monitoring apparatus (BFMA) configured to generate a data signal corresponding to a degree of filling of the patient's bladder; and a controller configured to receive the data signal from the BFMA and determine from the data signal a total number of voiding episodes occurring during one or more monitoring periods; wherein the controller is programmed to adjust one or more delivery parameters of the stimulation signal when the determined total number of voiding episodes is greater than a first target number.

26. The system of claim 25, wherein the controller is further programmed to adjust one or more delivery parameters when a determined total number of voiding episodes is less than a second target number.

27. The method of any of claim 25 to claim 26, wherein the controller is programmed to set a counter to zero at the beginning of a first monitoring period, determine from the data signal from the BFMA when a voiding episode has occurred, and increment the counter at each subsequent determined voiding episode to determine the total number of voiding episodes.

28. The system of any of claim 25 to claim 27, wherein the stimulation signal comprises a pulse pattern having one or more delivery parameters selected from a group consisting of amplitude, frequency, pulse width, pulse phase, pulse separation, burst pattern, quiescent period, and duty cycle.

29. The system of any of claim 25 to claim 28, wherein the stimulation signal comprises a waveform having one or more delivery parameters selected from a group consisting of amplitude, frequency, and duty cycle.

30. The system of any of claim 25 to claim 29, wherein the controller is further programmed to (a) iteratively adjust a selected individual stimulation signal delivery parameter, (b) determine whether observed results are positively affected, unaffected, or negatively affected, (c) further iterate the selected individual delivery parameter to a new value if the observed results are positively affected, and (d) return the selected individual delivery parameter to its prior value if the observed results are unaffected or negatively affected.

31. The system of any of claim 25 to claim 30, wherein the BFMA is configured to be located between the patient's pubic bone and the patient’s bladder and wherein the signal corresponds to a weight of urine in the bladder.