SYSTEMS, IMPLANT UNIT AND METHOD FOR THE TREATMENT OF HEAD AND FACIAL PAIN

Abstract

Disclosed herein is a neurostimulation system for treating head pain, the system comprising: an implant unit configured for implantation inside a subject's (700) body; an external unit configured for a location external to the subject's (700) body; and a charging and programming unit; wherein the external unit comprises: a processor; a power source (220); and a primary transmission unit (230) in electrical communication with the power source (220) and the processor; wherein the implant unit comprises: at least one lead (310); at least one pair of modulation electrodes (320) attached to the at least one lead (310); and a secondary transmission unit (330) in electrical communication with the at least one lead (310); and wherein the processor is configured to establish a coupling between the primary transmission unit (230) and the secondary transmission unit (330) and to transmit power from the power source (220) to the implant unit via said coupling. According to another aspect of the present disclosure, an implant unit for use in a neurostimulation system is described, wherein the implant unit is configured for implantation inside a subject's (700) body through an incision (600) subject's (700) skin, and wherein the implant unit is further configured for implantation inside the subject's (700) body through a tunnel (610). According to yet another aspect of the disclosure, a method for electrical stimulation of neuromuscular tissue using a neurostimulation system is described herewith, the method comprising: generating an electrical stimulation pattern with an external unit, the electrical stimulation pattern comprising at least one modulation signal; delivering the electrical stimulation pattern to an implant unit located inside a subject's (700) body; adjusting the electrical stimulation pattern, wherein adjusting the electrical stimulation pattern comprises increasing or decreasing a voltage, a current amplitude, a pulse frequency and/or a pulse width of the electrical stimulation pattern. Such a method may be valuable, for example, in pain management, where the propagation of pain signals is undesired.

Claims

1. A neurostimulation system for treating head and facial pain, the system comprising: an external unit configured for a location external to the subject's body; an implant unit configured for implantation inside a subject's body; and wherein the external unit comprises: a processor; a power source; and a primary transmission unit in electrical communication with the power source and the processor; wherein the implant unit comprises: at least one lead; at least one pair of modulation electrodes attached to the at least one lead; and a secondary transmission unit in electrical communication with the at least one lead and the modulation electrodes; and wherein the processor is configured to establish a coupling between the primary transmission unit and the secondary transmission unit and to transmit power and/or data from the power source to the implant unit via said coupling.

2. The system of claim 1, characterized in that the system comprises a charging unit.

3. The system according to claim 1, characterized in that the modulation electrodes are located along the at least one lead, wherein the electrodes are in particular spaced evenly along the lead.

4. The system according to claim 1, characterized in that the implant unit comprises tines for fixation of the at least one lead to a subcutaneous tissue of the subject.

5. The system according to claim 1, characterized in that the external unit is configured for attachment to the subject's skin.

6. The system according to claim 1, characterized in that the external unit comprises an energy harvesting unit configured for deriving energy from an external source.

7. The system according to claim 1, characterized in that the power source comprises a battery.

8. The system according to claim 1, characterized in that the charging unit is configured for charging the battery of the external unit.

9. The system according to claim 1, characterized in that the system further comprises a remote control configured for adjustment of the neurostimulation.

10. The system according to claim 1, characterized in that the coupling between the primary transmission unit and the secondary transmission unit comprises capacitive coupling, inductive coupling, light, ultrasound and/or radiofrequency coupling.

11. An implant unit for use in a neurostimulation system according to claim 1, wherein the implant unit is configured for implantation inside a subject's body through an incision in the subject's skin, and wherein the implant unit is further configured for implantation inside a tunnel in the subject's tissue.

12. The implant unit of claim 11, characterized in that the implant unit is configured for implantation through an incision of 0.5 to 3.5 cm in the subject's skin, and wherein the implant unit is further configured for implantation inside a tunnel in the subject's tissue leading from the incision (600) toward a location in the vicinity of the subject's inion.

13. The implant unit according to claim 11, characterized in that the implant unit is configured for location in a vicinity to an occipital nerve.

14. A method for electrical stimulation of neuromuscular tissue using a neurostimulation system according to claim 1, the method comprising: sending stimulation parameters from an external unit to an implant unit (300); generating an electrical stimulation pattern with the internal unit, the electrical stimulation pattern comprising at least one modulation signal; delivering the electrical stimulation pattern to an implant unit located inside a subject's body; adjusting the electrical stimulation pattern, wherein adjusting the electrical stimulation pattern comprises changing the electrode configuration and increasing or decreasing a voltage, a current amplitude, a pulse frequency and/or a pulse width of the electrical stimulation pattern.

15. The method according to claim 14, further comprising: forming an incision of 0.5 to 3.5 cm in the subject's skin; and implanting the implant unit inside a tunnel in the subject's tissue leading from the incision toward a location in the vicinity of the subject's inion.

16. The method according to claim 15, wherein the subject's inion is the subject's occipital nerve.

17. The method according to claim 14, further comprising: generating an electrical field between modulation electrodes of the implant unit, the electrical field modulating terminal fibers of the subject's nerve located between the modulation electrodes of the implant unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several examples of the disclosed subject matter. The drawings depict the following:

[0057] FIG. 1 depicts a schematic back view of a subject with a system for unilateral neurostimulation, comprising an implant unit and an external unit according to an exemplary embodiment of the present disclosure;

[0058] FIG. 2 depicts a schematic back view of a subject with a system for bilateral neurostimulation, comprising an implant unit and an external unit according to an exemplary embodiment of the present disclosure.

[0059] FIG. 3 depicts a schematic view of an exemplary embodiment of an implant unit comprising a unilateral modulation electrode configuration.

[0060] FIG. 4 depicts a schematic view of an exemplary embodiment of an implant unit comprising a bilateral modulation electrode configuration.

[0061] FIG. 5 depicts a flowchart of a system for treating head and facial pain according to an exemplary embodiment.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0062] FIG. 1 depicts a schematic back view of a subject with a system 100 for unilateral neurostimulation, the system comprising an implant unit 300 and an external unit 200 according to an exemplary embodiment of the present disclosure. The external unit 200 is configured for location external to the subject 700 or patient. The external unit 200 as shown in FIG. 1 is not attached to the subject. However, it may in fact be configured to be affixed to the subject 700. For example, for a subject suffering from head pain, the external unit 200 may be attached in the vicinity of the mastoid process, approximately at the level of the C2 vertebra. Suitable locations for the external unit 200 may be determined by communication between external unit 200 and the implant unit 300 implanted in the subject. The external unit 200 may comprise an external carrier 240 configured for attachment to the subject's 700 skin. For example, the carrier 240 may be a flexible skin patch configured for adherence to the subject's 700 skin, e.g. through adhesives or mechanical means. It is also possible to attach the external unit 200 to the subject's 700 skin via magnetic force, wherein the external carrier 240 comprises a magnetic pole, with a respective opposite pole located just beneath the subject's 700 skin. Further means of attachment can include a Hook-and-loop fastener based system (e.g. Velcro). The external carrier 240 may be flexible or rigid, or may have flexible portions and rigid portions. The external carrier 240 and/or the housing 250 of the external unit 200 may be constructed of any suitable material. In particular, the external unit or the housing 250 may include a flexible material such that the external unit may be configured to conform to a desired location. The material of the flexible substrate may include, but is not limited to, plastic, silicone, woven natural fibers, and other suitable polymers, copolymers, and combinations thereof. Any portion of external unit may be flexible or rigid, depending on the requirements of a particular application.

[0063] The external unit 200 may further be configured to be affixed to an alternative location proximate to the subject. For example, in one embodiment, the external unit 200 may be configured to fixedly or removably adhere to a strap or a band that may be configured to wrap around a part of a subject's body. Alternatively, or in addition, the external unit 200 may be configured to remain in a desired location external to the subject's body without adhering to that location.

[0064] The external unit 200 may comprise a housing 250. The housing 250 may include any suitable container configured for retaining components, e.g. a primary transmission unit 230 or a processor 210. In addition, while the external unit 200 is illustrated schematically in FIG. 1, the housing 250 may be any suitable size and/or shape and may be rigid or flexible.

[0065] The primary transmission unit 230 may be in the form of a coil antenna having a diameter of about cm to 5 cm, and may preferably be circular-shaped or oval-shaped. A coil antenna suitable for use as primary transmission unit may have any number of windings. Further, a coil antenna suitable for use as primary transmission unit may have a wire diameter of about 0.1 mm to 2 mm.

[0066] As previously discussed, the external unit 200 may be configured to adhere to a desired location. Accordingly, in some embodiments, at least one side of the housing 250 or external carrier 240 may include an adhesive material. The adhesive material may include a biocompatible material and may allow for a subject to attach the external unit 200 to the desired location and remove the external unit 200 upon completion of use. The adhesive may be configured for single or multiple uses of the external unit 200. Suitable adhesive materials may include, but are not limited to biocompatible glues, starches, elastomers, thermoplastics, and emulsions.

[0067] Further, the external unit 200 may be associated with a power source 220. The power source 220 may be removably couplable to the external unit 200 at an exterior location relative to external unit. Alternatively, the power source 220 may be permanently coupled to the external unit 200. If the power source 220 is permanently coupled to external unit 200, it is intended that the power source 220 be rechargeable. The power source 220 may further include any suitable source of power configured to be in electrical communication with the processor. In one embodiment, for example the power source 220 may include a battery 221.

[0068] The system of FIG. 1 further discloses an implant unit 300 comprising a stimulation bridge 350, the stimulation bridge 350 including a lead 310, the secondary transmission unit 330 and pairs of modulation electrodes 320. The lead 310 in FIG. 1 is approximately 10 cm long and comprises eight pairs of modulation electrodes 320 (octopolar lead), evenly spaced apart along the lead 310. Further, the implant unit 300 is battery-free, making it possible for the implant unit 300 to be in the form of the stimulation bridge 350 shown in FIG. 1. The implant unit 300 is therefore suitable for use in a neurostimulation system 100 as disclosed herein, since it is configured for implantation inside a subject's 700 body through an incision 600 the subject's 700 skin, wherein the incision is 0.5 to 3.5 cm long. Furthermore, the implant unit 100 may be configured for implantation inside a tunnel 610 in the subject's tissue, wherein the tunnel 610 leads from the incision 600 towards a location in the vicinity of the subject's 700 inion 710, e.g. in a vicinity of an occipital nerve 720.

[0069] Upon coupling of the primary transmission unit 230 of the external unit 200 with the secondary transmission unit 330 of the implant unit 300, a sub-modulation signal or a modulation signal may be transmitted from the external unit 200 to the modulation electrodes 320 of the implant unit 300. A circuitry of the external unit 200 may for example be configured to generate an electric primary signal on the primary transmission unit 230 that may cause an electric secondary signal on the secondary transmission unit 330 in the implant unit 300. The secondary signal may then be configured to generate an electric field between the modulation electrodes 320, sufficient to modulate the terminal fibers of a nerve, when spaced apart thereof.

[0070] FIG. 2 depicts a schematic back view of a subject with a system 100 for bilateral neurostimulation, comprising an implant unit 300 and an external unit 200 according to an exemplary embodiment of the present disclosure. The embodiment shown in FIG. 2 differs from that of FIG. 1 in that a long lead 310 or stimulation bridge 350 is used, which is suitable for bilateral stimulation. The lead 310 of the stimulation bridge 350 shown in FIG. 2 is approximately 20 cm long. Preferably, it is configured for an implantation procedure using two incisions 600.

[0071] In particular, bilateral neurostimulation requires one small incision 600 of 3 cm length at the level of the mastoid process and a second incision 600, the second incision being located 1 to 1.5 cm above the inion for implantation of the stimulation bridge 350. With a stimulation 350 bridge having a lead 310 that is longer than 10 cm, i.e. that is configured for bilateral stimulation, it is possible to stimulate a large neural area of the subject 700 with only to minor incisions 600. Thus, the medical procedure of implanting the implant unit in the subject 700 can be kept short and still allow for a very efficient neural stimulation.

[0072] FIG. 3 depicts a schematic view of an exemplary embodiment of an implant unit 300 comprising a unilateral modulation electrode 320 configuration. In particular, the implant unit 300 of FIG. 3 is composed of the stimulation bridge 350 the secondary transmission unit 330. The stimulation bridge 350 comprises a lead 310 of approximately 10 cm of length as well as and eight pairs of modulation electrodes 320 (also labeled E1 to E8 in FIG. 3) attached to the lead 310 (octopolar lead). According to the embodiment shown in FIG. 3, the modulation electrodes 320 are evenly spaced apart along the lead 310.

[0073] The implant unit 300 of FIG. 3 is battery-free, making it possible for the implant unit 300 to be in the slim and relatively small form of the stimulation bridge 350 shown in FIG. 3. Such an implant unit 300 is suitable for use in a neurostimulation system 100 as disclosed herein, since it is configured for implantation inside a subject's 700 body through an incision 600 the subject's 700 skin, wherein the incision is 0.5 to 3.5 cm long. Furthermore, the implant unit 300 may be configured for implantation inside a tunnel 610 in the subject's 700 tissue, wherein the tunnel 610 leads from the incision 600 towards a location in the vicinity of the subject's 700 inion 710, e.g. in a vicinity of an occipital nerve 720.

[0074] In the electrode 320 configuration of the stimulation bridge 350 of FIG. 3, any individual modulation electrode E1 to E8 can be programmed as an Anode (A) or a Cathode (C) or it can be left unconnected (NC). According to a preferred embodiment, at least one electrode 320 may be defined as Anode and/or at least one electrode 320 may be defined as Cathode. The remaining to two to seven electrodes may be put in parallel as Anode or Cathode.

[0075] FIG. 4 depicts a schematic view of an exemplary embodiment of an implant unit 300 comprising a bilateral modulation electrode 320 configuration. The implant unit 300 of FIG. 4 differs from the embodiment of FIG. 3 in the stimulation bridge 350 comprises a longer lead 310, suitable for bilateral stimulation. The lead 310 of the stimulation bridge 350 shown in FIG. 3 is approximately 20 cm long.

[0076] As shown on FIG. 4, the stimulation bridge 350 is made up of two connected segments, each segment comprising eight pairs of modulation electrodes 320a and 320b respectively. The modulation electrodes 320a attached to the segment of the stimulation bridge 350 that is connected to the secondary transmission unit 330 are called proximal electrodes 320a (also labeled PE1 to PE8 in FIG. 4). Likewise, the modulation electrodes 320b attached to the segment of the stimulation bridge 350 that is not directly connected to the secondary transmission unit 330 are called distal electrodes 320b (also labeled DE1 to DE8 in FIG. 4).

[0077] According to the electrode 320 configuration of the stimulation bridge 350 of FIG. 4, any individual modulation electrode PE1 to PE8 or DE1 to DE8 can be programmed as an Anode (A) or a Cathode (C) or it can be left unconnected (NC). According to a preferred embodiment, at least one electrode 320 may be defined as Anode and/or at least one electrode 320 may be defined as Cathode.

[0078] FIG. 5 depicts a flowchart of a system 100 for treating head and facial pain according to an exemplary embodiment. According to this embodiment, an external unit 200 may be attached to the external carrier 240 which is attached to a patient's skin. This patient external unit 200 (Patient EU in FIG. 5) establishes, via its primary transmission unit 230, a transmission link with an implant unit 300 implanted beneath the patient's 700 skin. Furthermore, the patient external unit 200 may supply power to the implant unit 300 via induction.

[0079] According to the shown embodiment of the system 100, the implant unit 300 is configured to communicate with the external unit 200 via wireless transmission. The implant unit may further comprise a bootloader which starts a software program installed on a processor of the implant unit. Lastly, the implant unit 300 may be configured to run and diagnose stimulation therapy and send alters and warnings (A&W) to the external unit 200 in case the implant unit 300 encounters problems.

[0080] The system 100 further comprises a charging unit 400 for charging the external unit 200 via inductive coupling. However, according to the embodiment of FIG. 5, the charging unit 400 may further be configured to collect A&W data stored on the patient external unit 200 and sent to the external unit 200 from the implant unit 300. Furthermore, the charging unit 400 may comprise a charger LED and an emergency LED, which can be turned on or off. E.g. the charger LED may be turned on for as long as the external unit 200 is being charged. Likewise, the emergency LED may be turned on when the charging unit 400 receives A&W data from the external unit 200. Additionally, the charging unit 400 may connect to a web server and upload log files or A&W reports.

[0081] Lastly, as shown by FIG. 5 the system 100 may comprise a physician programming unit 800 connectable to the external unit 200. When the external unit 200 is connected to the physician programming unit 800, it may also be referred to as physician external unit 200 (see Physician EU in FIG. 5). The physician external unit 200 may then either be the same device as the patient external unit (see Patient EU in FIG. 5) or it may be a different external device used solely by the physician. The physician programming unit 800 may be an external computing unit, e.g. a PC or a similar handheld or portable device like a tablet or a smartphone. Together, the physician external unit 200 and the physician programming unit 800 are configured to prepare a therapy template and store its configuration under specific names. Furthermore, the physician programming unit 800 may serve for secure identification of the implant unit 300 and establish a secure pairing between the implant unit 300 and the physician external unit 200. Further functions of the physician programming unit 800 and the physician programming unit 200 may comprise: Verifying patient history log files stored in the implant unit 300; prepare/load a therapy and run a test stimulation sequence during patient visits; program the tested therapy during patient visits; receive a status report from the implant unit 300 (e.g. alerts or warnings, history log files, etc.) during the patient visits; provide a user-friendly interface to visualize the therapy before programming (e.g. show electrode configuration, current amplitudes, pulse durations, ON-OFF period, etc.).

[0082] The invention is not limited to one of the embodiments described herein but may be modified in numerous other ways.

[0083] All features disclosed by the claims, the specification and the figures, as well as all advantages, including constructive particulars, spatial arrangements and methodological steps, can be essential to the invention either on their own or by various combinations with each other.

LIST OF REFERENCE NUMERALS

[0084] 100 System [0085] 200 External unit [0086] 210 Processor [0087] 220 Power source [0088] 221 Battery [0089] 230 Primary transmission unit [0090] 240 External carrier [0091] 250 Housing [0092] 260 Energy harvesting unit [0093] 300 Implant unit [0094] 310 Lead [0095] 320 Modulation electrodes [0096] 330 Secondary transmission unit [0097] 340 Flexible carrier [0098] 350 Stimulation bridge [0099] 400 Charging unit [0100] 500 Remote control [0101] 600 Incision [0102] 610 Tunnel [0103] 700 Subject [0104] 710 Inion [0105] 720 Occipital nerve [0106] 800 Physician programming unit