TUMESCENSE MONITORING SYSTEM FOR DIAGNOSING ERECTILE DYSFUNCTION AND METHODS OF USE

Abstract

Systems and methods for monitoring penile tumescence are provided that overcome the drawbacks of previously known systems by providing a wearable formed of a flexible and elastic tube having a plurality of sensors disposed on or embedded within it, the wearable configured to be applied to a penis of a subject, and a spaced-apart controller operatively coupled to retrieve data regarding circumferential and axial dimensional changes and penile rigidity from the plurality of sensors and transmit that data to an external computer or smartphone for analysis and display. The plurality of sensors may be coupled to the spaced-apart controller via a flexible lead or wirelessly using a passive RFID system.

Claims

1. A system for monitoring penile tumescence of a subject, the system comprising: a wearable comprising a tube of biocompatible flexible and elastic material configured to a disposed on a penis of the subject, the tube having a plurality of sensors configured to generate data indicative of circumferential and axial dimensional changes of the penis; and a controller operatively coupled to the plurality of sensors to retrieve and store the data from the plurality of sensors, the controller configured to be disposed at a location spaced apart from the penis, the controller comprising a transceiver configured to transmit the data to an external computer or smartphone for analysis and display.

2. The system of claim 1, wherein at least some of the plurality of sensors comprise flexible strain gauges.

3. The system of claim 2, wherein the flexible strain gauges comprise a capacitive strain gauge comprising an insulated flexible membrane encapsulated by a pair of conductive materials, a thickness of the insulated flexible membrane configured to vary responsive to circumferential and axial dimensional changes of the penis, and wherein the controller is configured to measure capacity of the capacitive strain gauge as the thickness of the insulated flexible membrane varies.

4. The system of claim 2, wherein the flexible strain gauges comprise an optical strain gauge comprising an optical fiber operatively coupled to a light source and a photodetector configured to measure light intensity, and wherein the controller is configured to: cause the light source to emit a beam of light having a predetermined light intensity through the optical fiber, the beam of light configured to undergo interference as it travels through the optical fiber, the interference configured to vary responsive to strain of the optical fiber due to circumferential and axial dimensional changes of the penis; receive data from the photodetector indicative of a final light intensity of the beam of light measured by the photodetector; and calculate a difference between the predetermined light intensity and the final light intensity of the beam of light, the difference proportional to the strain of the optical fiber.

5. The system of claim 1, wherein the wearable further comprises one or more sensors configured to apply a contractile force on the penis during a tumescence event, and wherein the controller is configured to measure penile rigidity based on the contractile force applied to the penis during the tumescence event.

6. The system of claim 5, wherein the one or more sensors comprise an electroactive polymer structure configured to apply the contractile force on the penis during the tumescence event.

7. The system of claim 6, wherein the electroactive polymer structure comprises a dielectric elastomer actuator comprising alternating layers of an elastomer and one or more electrodes, a size and shape of the elastomer configured to vary when stimulated by an electric field of the one or more electrodes to thereby apply the contractile force on the penis.

8. The system of claim 5, wherein the one or more sensors comprise: a wire having a looped end and a free end configured to extend around a circumference of the penis and through the looped end; a spool coupled to the free end of the wire; and a micromotor operatively coupled to the controller and configured to rotate the spool, wherein the controller is configured to actuate the micromotor to rotate the spool and cause the wire to apply the contractile force on the penis during the tumescence event.

9. The system of claim 5, wherein the one or more sensors comprise: a wire having a looped end and a free end configured to extend around a circumference of the penis and through the looped end; a magnet coupled to the free end of the wire; and an electromagnet assembly operatively coupled to the controller and configured to generate an electromagnetic field, wherein the controller is configured to actuate the electromagnet assembly to generate the electromagnetic field to move the magnet relative to the electromagnet assembly and cause the wire to apply the contractile force on the penis during the tumescence event.

10. The system of claim 9, wherein the electromagnet assembly comprises a single electromagnet.

11. The system of claim 9, wherein the electromagnet assembly comprises a series of electromagnets arranged in a linear pattern.

12. The system of claim 5, wherein the one or more sensors comprise a wire comprising a shape memory alloy, a size and shape of the wire configured to vary when heated or stimulated by an electric field to apply the contractile force on the penis during the tumescence event.

13. The system of claim 12, wherein a resistivity of the wire is configured to vary responsive to circumferential and axial dimensional changes of the penis, and wherein the controller is configured to measure the resistivity of the wire.

14. The system of claim 12, wherein the wire comprises Nitinol.

15. The system of claim 1, wherein the controller further comprises a housing and an adhesive pad coupled to the housing, wherein the adhesive pad is configured to removably secure the controller to a groin area, a lower abdomen, or an upper thigh of the subject.

16. The system of claim 15, wherein the plurality of sensors is coupled to the controller via a flexible lead.

17. The system of claim 1, wherein the wearable further comprises at least one RFID tag.

18. The system of claim 17, wherein the controller further comprises an RFID reader circuit for interrogating the RFID tag.

19. The system of claim 1, wherein the controller further comprises a rechargeable battery.

20. The system of claim 1, wherein the transceiver is configured for bi-directional communication with the external computer or the smartphone.

21. The system of claim 1, wherein software installed on the external computer is configured to provide real-time feedback to physician controller software for selecting electrode configuration or selection of electrostimulation parameters for an implantable array of penile electrostimulation electrodes.

22. The system of claim 1, wherein the tube comprises a latex or silicone rubber.

23. The system of claim 1, wherein the tube further comprises a bacteriostatic coating.

24. A method of monitoring penile tumescence of a subject, the method comprising: applying a wearable comprising a tube of biocompatible flexible and elastic material on a penis of the subject, the tube having a plurality of sensors configured to generate data indicative of circumferential and axial dimensional changes of the penis; removably securing a controller to the subject at a location spaced apart from the penis, the controller operatively coupled to the plurality of sensors; operating the controller to retrieve and store data from the plurality of sensors; and transmitting the data to an external computer or smartphone for analysis and display.

25. The method of claim 24, further comprising applying a contractile force on the penis during a tumescence event to generate data indicative of penile rigidity.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] FIG. 1 is a schematic diagram of an exemplary system arranged in accordance with the principles of the present invention for use in monitoring penile tumescence.

[0039] FIG. 2 is a schematic view depicting exemplary placement of the components of the system of FIG. 1 in use with a subject.

[0040] FIG. 3 is a schematic diagram of the internal components of a first embodiment of the controller of the present invention.

[0041] FIG. 4 is a schematic diagram of the electronic components of an exemplary embodiment of the implantable device.

[0042] FIG. 5 is schematic diagram of the internal components of an alternative embodiment of the controller of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0043] The present invention is a system and methods for monitoring penile tumescence that overcome the disadvantages of prior art systems, and in particular, discomfort caused previously known systems and methods. The tumescence monitoring system of described herein is expected to provide accurate results with less inconvenience to the wearer, and especially when used to monitoring nocturnal penile tumescence. In addition, the system may be used in conjunction with the implantable electrostimulation system described in above-incorporated U.S. Pat. No. 11,141,589 to assess the strength of an erection stimulated by specific electrode configurations and stimulation parameters, to enable optimization of the electrode configuration and electrostimulation parameters.

[0044] Referring to FIGS. 1 and 2, exemplary system 10 of the present invention is described. In FIG. 1, components of the system are not depicted to scale on either a relative or absolute basis. System 10 comprises condom-like wearable 20 coupled via flexible lead 25 to controller 30, which in turn wirelessly communicates with personal computer 40 and/or smartphone 45. As best shown in FIG. 2, wearable 20 is disposed on the penis of the subject, and controller 30 may be adhered via a biocompatible adhesive pad to the subject's groin area, lower abdomen, and/or upper thigh, and coupled to wearable 20 via flexible lead 25. When so arranged, controller 30 may communicate data to personal computer 40 and/or smartphone 45 via a known wireless technology, such as WiFi or Bluetooth.

[0045] Referring still to FIG. 1, wearable 20 preferably comprises a biocompatible elastic material, such as latex or silicone rubber, and includes a plurality of flexible sensors 22, 24 mounted thereon, or embedded within its thickness, for example, strain gauges, which are configured to measure changes in the circumference of the subject's penis, as well as axial extension thereof. Sensors 22 and 24 may be of different types, as best suited for measuring circumferential or axial strains, and generally may be of the type of flexible strain gauges described by C. Zhao et al, in the article entitled “3D-printed highly stable flexible strain sensor based on silver-coated-glass fiber-filled conductive silicone rubber.” Materials and Design 193 (2020) 108788, https://doi.org/10.1016/j.matdes.2020.108788.

[0046] Additionally, or alternatively, sensors 22 and 24 may be of the type of flexible capacitive strain gauges described by H. Souri et al, in the article entitled “Wearable and Stretchable Strain Sensors: Materials, Sensing Mechanisms, and Applications,” Advanced Intelligent Systems (2020) 2000039, https://doi.org/10.1002/aisy.202000039. For example, each flexible capacitive strain gauge may include an insulated flexible membrane encapsulated by a pair of conductive materials, e.g., a dielectric, such that upon deformation, the thickness of the insulated flexible membrane varies based on the degree of deformation. Accordingly, the capacity of the flexible capacitive strain gauge may be measured, which is indicative of the tumescence of the subject's penis.

[0047] Additionally, or alternatively, sensors 22 and 24 may be of the type of flexible optical strain gauges described by J. Guo et al. in the article entitled “Highly Flexible and Stretchable Optical Strain Sensing for Human Motion Detection,” Optica 4, 1285-1288 (2017), https://doi.org/10.1364/OPTICA.4.001285, or by J. Jeong et al. in the article entitled “Highly Stretchable Polymer-based Optical Strain Sensor for Integration with Soft Actuator,” 2019 IEEE International Conference on Consumer Electronics (ICCE), Las Vegas, NV, USA, 2019. pp. 1-3, doi: 10.1109/ICCE.2019.8661937, https://iecexplore.ieec.org/document/8661937. For example, each flexible optical strain gauge may include an optical fiber operatively coupled to a light source and a photodetector configured to measure the intensity of a beam of light through the optical fiber. Accordingly, the light source may send a beam of light through the optical fiber, which undergoes interference due to changes in the optical fiber's optical properties caused by strain on the optical fiber. The power difference between the light source and the photodetector is proportionate to the strain, and thus indicative of the tumescence of the subject's penis.

[0048] Sensors 22 and 24 may be coupled to grid 26 of elastic conductors disposed on or embedded in the wearable to permit the sensors to be individually read by controller 30 via flexible lead 25. As will be understood, wearable 20 is elastic and has sufficiently low durometer to be capable of undergoing circumference and axial expansion and contraction to mimic the degree of flaccidness or tumescence of penis P of the subject.

[0049] Wearable 20 is designed to be worn by the subject while sleeping to continuously monitor the state of the penis, and may include aperture 27 at its distal end to permit the subject to get up to urinate during the night without removing wearable 20. Flexible lead 25 may comprise a wire lead or flexible ribbon, and preferably has a length. e.g., 25-40 cm, sufficient to permit connector 28 of lead 25 to be connected to controller 30 when the controller is adhered to the subject's groin area, lower abdomen, and/or upper thigh. Wearable 20 may include a bacteriostatic coating to permit the wearable to be worn on a number of successive nights to collect tumescence data, e.g., three consecutive nights, before being discarded. Alternatively, wearable 20 may be designed for use for a single night and replaced with a fresh wearable on subsequent nights for which data is to be acquired.

[0050] In one embodiment, controller 30 comprises plastic housing 31 that contains a printed circuit board having electronics for reading the sensors on wearable 20. Controller 30 may be removably fastened to a biocompatible adhesive patch 32, which permits the controller to be removably attached to the subject's groin area, lower abdomen, and/or upper thigh. Adhesive patch 32 may have biocompatible adhesive on both sides to permit the patch to be replaced daily. As depicted in FIG. 1, housing 31 of controller 30 preferably has a dome-like form, to minimize abrupt edges that may snag on the subject's clothing or sleepwear. In addition, controller 30 has port 33 for accepting connector 28 of wearable 20.

[0051] Referring now to FIG. 3, the electronic components of controller 30 are described. In particular, controller 30 includes processor 33, non-volatile memory 34, volatile memory 35, battery 36, transceiver 37, antenna 38, and bus 39. Bus 39 couples the internal components 33-38 of the controller, and includes a port for accepting connector 28 of flexible lead 25, thereby coupling sensors 22, 24 to controller 30. Processor 33 may be a general purpose processor capable of reading programmed instructions stored in non-volatile memory 34 to read and analyze the signals generated by sensors 22, 24 to generate tumescence data using volatile memory 35. The programmed instructions also may store the tumescence data in storage locations of non-volatile memory 34, and subsequently transfer that data to personal computer 40 and/or smartphone 45 using transceiver 37 and antenna 38. Alternatively, processor 33 may be a special purpose built processor for handling collection and analysis of the data received from wearable 20. Battery 36 may be a lithium ion battery with sufficient capacity to support operation of processor 33, reading of sensors 22 and 24, and support operation of transceiver 37 for a desired period, such as 3 to 5 days. When controller 30 is not in use by a subject, battery 36 may be recharged, e.g., using a conventional charging circuit and jack (not shown).

[0052] Transceiver 37 and antenna 38 preferably are configured for bi-directional communication with personal computer 40 and/or smartphone 45 to transfer tumescence data from controller 30 to computer 40 and/or smartphone 45, and also to update the programmed instructions stored in non-volatile memory 34. Transceiver 37 may be compliant with any of a number of well-known wireless standards, such as IEEE 802.11 for WiFi or Bluetooth standard, IEEE 802.15.1 or as currently promulgated by the Bluetooth Special Interest Group.

[0053] Personal computer 40 may belong either to the subject whose erectile function is being evaluated or the subject's physician, while smartphone 45 preferably belongs to the subject. In one preferred embodiment, personal computer 40 may be programmed with software for bi-directionally communicating with controller 30 to retrieve tumescence data stored in non-volatile memory 34, or to update the programmed instructions stored in non-volatile memory 34 for processor 33. Computer 40 and/or smartphone 45, in addition, may contain additional software for analyzing and displaying the tumescence data, for example, to show nocturnal erection events, including circumferential and length changes.

[0054] In accordance with one aspect of the present invention, computer 40 also may contain the software for external physician controller 500 for programming configuration of the electrode array and electrostimulation parameters used by the implantable electrode array described with respect to FIGS. 1 and 7, and in column 12, lines 10-64 of U.S. Pat. No. 11,141,589. In this case, the software of the tumescence monitoring system in computer 40 may directly interact with the software for external physician controller 500 to directly measure the erectile response to a selected electrode configuration and/or set of electrostimulation parameters. Accordingly, the tumescence monitoring system of the present invention may be used to interact with, and thus optimize, the erectile response achievable for the implantable electrode array, as desired to achieve a desired erectile response or response for penile rehabilitation.

[0055] Still referring to FIGS. 1 to 3, an alternative embodiment of wearable 20 may comprise an electroactive polymer, such as a dielectric elastomer, for measuring penile rigidity during tumescence events. In this case, sensors 22 may instead comprise electroactive polymer structures embedded within the wall of wearable 20 and be coupled via flexible lead 25 to a voltage source. i.e., battery, in controller 30. Upon application of a voltage, the electroactive polymer may contract, as described for example in U.S. Pat. No. 7,862,551 to Bates. Additionally. or alternatively, the electroactive polymer may be of the type of dielectric elastomer actuator (DEA) described by S. Perrin, in the article entitled “A Tiny Pump Comes to the Aid of Weakened Hearts” (available at: https://actu.epfl.ch/news/a-tiny-pump-comes-to-the-aid-of-weakened-hearts/), or by T. Martinez, in the article entitled “A Novel Soft Cardiac Assist Device based on a Dielectric Elastomer Augmented Aorta: An In Vivo Study” (2022), https://doi.org/10.1002/btm2.10396. For example, the DEA may include a plurality of alternating layers of elastomer and electrodes that are joined together, such that the elastomer exhibits a change in size or shape when stimulated by an electrical field applied by the electrodes. Accordingly, the change exhibited by the elastomer layers may be measured, which is indicative of penile rigidity. Additionally, or alternatively, sensors 22 may instead comprises other actuator types for measuring penile rigidity, as described in further detail below.

[0056] As employed in wearable 20 of the present invention, during nocturnal monitoring with system 10, when a change in penile circumference is detected by sensors 24 (e.g. more than a 5 mm increase), controller 30 may deliver an electric field to induce a short controlled contraction of the electroactive polymer structures and/or DEA. Based on the force of the contraction imposed by the electroactive polymer structures and the resulting change in circumference detected by sensors 24, instantaneous stiffness/rigidity of the penis may be calculated by controller 30. When the penile circumference returns to a baseline value, application of voltage by the controller to the electroactive polymer structures is discontinued. Preferably such measurements may be repeated every 10 to 20 minutes beginning shortly after a change in penile circumference is detected during an erection event, and the cycle repeated for every subsequent erectile event.

[0057] Referring now to FIGS. 4 and 5, a further alternative embodiment of penile tumescence monitoring system 50 of the present invention is described. In FIG. 4, components of the system again are not depicted to scale on either a relative or absolute basis. System 50 is similar to the embodiments of system 10 described with respect to FIGS. 1-3, except that in system 50 the sensors disposed on or within wearable 60 wirelessly communicate with controller 70. Controller 70 in turn wirelessly communicates with personal computer 80 and/or smartphone 85, as in the earlier embodiment. System 50 is configured so that, similarly to FIG. 2, wearable 60 is disposed on the penis of the subject, while controller 70 may be adhered via a biocompatible adhesive pad to the subject's groin area or lower abdomen, removably secured to the subject's upper thigh using an elastic or Velcro® strap, or even placed on a nightstand near the subject's bed. Wearable 60 wirelessly transmits data to controller 70, and thus omits the need for a flexible lead, further reducing subject discomfort. Controller 70 may communicate data to personal computer 80 and/or smartphone 85 via a known wireless technology, such as WiFi or Bluetooth.

[0058] Referring still to FIG. 4, wearable 60 preferably comprises a biocompatible elastic material, such as latex or silicone rubber, and has plurality of sensors 61 mounted thereon, or embedded within its thickness. Sensors 61 may be flexible strain gauges, 62 and 64, such as described in the above identified articles, and may be of the same type, but oriented differently on wearable 60 to measure circumferential and length changes of the subject's penis. Alternatively, strain gauges 62 and 64 may be of different types as best suited for measuring circumferential or axial strains. As a further alternative embodiment, wearable 60 also may comprise electroactive polymer structures, as described in the preceding embodiment. As a yet further alternative embodiment, some of sensors 61 may comprise flexible bands that have circumferentially overlapping portions that serve as rheostats, so that a resistance value generated by the band changes as a function of its circumferential or axial extension. Additionally, or alternatively, sensors 61 may be of the type of a wire band formed of a shape memory alloy, e.g., Nitinol, that may return to its original shape when heated above its transformation temperature or exposed to an electrical current, as described in the article entitled “Smart Grippers Powered by Shape Memory Alloys” (available at: https://www.epfl.ch/labs/lai/rescarch/page-101809-en-html/page-153681-en-html/). The wire band may be permanently deformed to a desired shape and size by being heated above its shape-setting temperature. e.g., 400° C.-550° C., and then cooled down while maintaining the desired shape and size. Moreover, upon deformation, the resistivity of the Nitinol wire band will vary based on the degree of deformation. Accordingly, the resistance value of the wire band may be measured, which is indicative of penile rigidity.

[0059] In accordance with once aspect of the invention, sensors 61 may each include an RFID tag that periodically is wirelessly interrogated by controller 70 to generate a value corresponding to penile axial or circumferential dimensional changes, or which permit the calculation of penile rigidity. Such RFID-enabled strain gauges are described, for example, in U.S. Pat. No. 9,464,948 to Carroll et al., which is incorporated herein by reference. For example, each of sensors 61 may be interrogated by controller 70 every second or even more frequently to provide a nearly continuous stream of data indicative of the tumescence of penis P.

[0060] Alternatively, sensors 61 of wearable 60 may be coupled to grid 66 of elastic conductors disposed on or embedded in the wearable, such that a common RFID tag may be employed by controller 70 to individually read sensors 61. As will be understood, wearable 60 is elastic and has sufficiently low durometer to undergo circumference and axial expansion and contraction to mimic the degree of flaccidness or tumescence of penis P of the subject.

[0061] Wearable 60 also is designed to be worn by the subject while sleeping to continuously monitor the state of the penis, and may include aperture 67 at its distal end to permit the subject to get up to urinate during the night without removing the wearable. Wearable 60 may include a bacteriostatic coating to permit the wearable to be worn on a number of successive nights to collect tumescence data, e.g., three consecutive nights, before being discarded. Alternatively, wearable 60 may be designed for use for a single night and replaced with a fresh wearable on subsequent nights for which data is to be acquired.

[0062] In the embodiment of FIGS. 4 and 5, controller 70 comprises plastic housing 71 that contains a printed circuit board having electronics for wirelessly reading the sensors on wearable 60, and storing and communicating such data to computer 80 and/or smartphone 85. As discussed above, controller 70 may be removably fastened to the subject's groin or lower abdomen using biocompatible adhesive patch 72, strapped to the subject's upper thigh using a strap (not shown), or placed on a table or nightstand in close proximity to the subject's bed. Adhesive patch 72 may have biocompatible adhesive on both sides to permit the patch to be replaced daily. As for the preceding embodiment, housing 71 of controller 70 preferably has a smooth dome-like form to minimize edges that could snag on the subject's clothing or sleepwear.

[0063] Referring to FIG. 5, the electronic components of controller 70 are described. Controller 70 includes processor 73, non-volatile memory 74, volatile memory 75, battery 76, transceiver 77, antenna 78, internal bus 79, and RFID reader circuit 81. In FIG. 5, each of sensors 61 is depicted having an associated RFID tag 61a, to permit sensors 61 to be individually read by controller 70. Processor 73 may be a general purpose processor capable of reading programmed instructions stored in non-volatile memory 74 to read and analyze the signals generated by sensors 62, 64 to generate tumescence data using volatile memory 75. The programmed instructions also may store the tumescence data in storage locations of non-volatile memory 74, and subsequently transfer that data to personal computer 80 and/or smartphone 85 using transceiver 77 and antenna 78. Alternatively, processor 73 may be a special purpose built processor for handling collection and analysis of the data received from wearable 60. Battery 76 may be a lithium ion battery with sufficient capacity to support operation of processor 73, reading of sensors 62 and 64 via RFID reader circuit 81, and to support operation of transceiver 77 for a desired period, such as 1 to 5 days. Battery 76 also should be capable of storing sufficient energy to energize the electroactive polymer structures in wearable 60, if present, for evaluating penile rigidity. When controller 70 is not in use by a subject, battery 76 may be recharged, e.g., using a conventional charging circuit and jack (not shown),

[0064] Transceiver 77 and antenna 78 preferably are configured for bi-directional communication with personal computer 80 or smartphone 85 to transfer tumescence data from controller 70 to computer 80 and/or smartphone 85, and also to update the programmed instructions stored in non-volatile memory 74. Transceiver 77 may be compliant with any of a number of well-known wireless standards, such as IEEE 802.11 for WiFi or Bluetooth standard, IEEE 802.15.1 or as currently promulgated by the Bluetooth Special Interest Group.

[0065] RFID tags 61a preferably are passive, and are read by collecting radio-frequency energy emitted by RFID reader 81, using the principle of operation as described in the above-incorporated U.S. Pat. No. 9,464,948. Data retrieved from sensors 61 by RFID reader circuit 81 is processed by processor 73 and stored in non-volatile memory 74 for subsequent transmission and analysis by computer 80 and/or smartphone 85.

[0066] As in the preceding embodiment of system 10, personal computer 80 of system 50 may belong either to the subject whose erectile function is being evaluated or the subject's physician, while smartphone 85 preferably may belong to the subject. Personal computer 80 preferably is programmed with software for bi-directionally communicating with controller 70 to retrieve tumescence data stored in non-volatile memory 74, and to update the programmed instructions stored in non-volatile memory 74 that are used by processor 73. Computer 80 or smartphone 85, in addition, may contain additional software for analyzing and displaying the tumescence data, for example, to show real-time erection events or previously recorded nocturnal erection events, including circumferential and length changes and rigidity values.

[0067] As for the preceding embodiment, computer 80 also may contain the software for external physician controller 500 for programming configuration of the electrode array and electrostimulation parameters used by the implantable electrode array described with respect to FIGS. 1 and 7, and in column 12, lines 10-64 of U.S. Pat. No. 11,141,589. In this case, the software of the tumescence monitoring system in computer 80 may directly interact with the software for external physician controller 500, under the control of the subject's physician or automatically, to measure the erectile response to a selected electrode configuration and/or set of electrostimulation parameters. In this manner, the tumescence monitoring system of the present invention may be used to provide near real-time data to external physician controller 500 used to configure operation of the implantable electrode array, thus optimizing the erectile response attained by the implantable electrode array, to achieve a desired erectile response or penile rehabilitation regime.

[0068] Alternative systems for measuring penile rigidity are described. The system may include a wire connected to a spool configured to be activated by a micromotor, e.g., a coreless DC brushed micromotor. The wire may be positioned around the circumference of the subject's penis. For example, the wire may have a looped end opposite to a free end of the wire, such that the free end of the wire may extend around the circumference of the subject's penis and through the looped end, and connected to the spool. Moreover, a micromotor may be programmed to actuate the spool to rotate and wind the wire, thereby applying a force to the wire around the penis. Displacement of the wire responsive to actuation of the micromotor provides an output function that correlates to the compressibility or rigidity of the penis. Unlike the RigiScan system, the single small wire and the micromotor are less intrusive and less uncomfortable to the subject. e.g., during sleep.

[0069] The system may include a wire connected to a ferromagnetic or conductive material. e.g., a magnet, which may be attracted by an electromagnet assembly. The wire may be positioned around the circumference of the subject's penis. For example, the wire may have a looped end opposite to a free end of the wire, such that the free end of the wire may extend around the circumference of the subject's penis and through the looped end, and connected to a magnet. The electromagnetic assembly may comprise a single electromagnet, or alternatively, a series of electromagnets arranged in a linear pattern forming a linear actuator. Accordingly, the electromagnetic assembly may be programmed to be actuated to emit an electromagnet field, which causes movement of the magnet relative to the electromagnetic assembly, thereby applying a force to the wire around the penis. Displacement of the wire responsive to actuation of the electromagnetic assembly provides an output function that correlates to the compressibility or rigidity of the penis.

[0070] While various illustrative embodiments of the invention are described above, it will be apparent to one skilled in the art that various changes and modifications may be made therein without departing from the invention.