Wireless neural stimulator with injectable

Abstract

Neural stimulator systems with an external magnetic coil to produce changing magnetic fields is applied outside the body, in conjunction with one or more tiny injectable objects that concentrates the induced electric field to a highly-targeted location. These systems include a driver circuit for the magnetic coil that allows for high voltage and fast pulses in the coil, while requiring low-voltage power supply that may be powered by a wearable or portable external device, along with the coil and driver circuit.

I claim: 
     
         1 . A neuromodulation system, comprising:
 a. at least one elongate conductor configured for placement inside the body with one end adjacent to the site to be stimulated; and   b. a magnetic field generator configured to be placed outside the body and to generate a time varying magnetic field perpendicular to a longitudinal axis of the conductor.   
     
     
         2 . The system of  claim 1 , wherein the elongate conductor comprises a material selected from a group consisting of a metal, a resistor, and carbon fiber. 
     
     
         3 . The system of  claim 2 , wherein the metal is copper, tungsten, chromium, steel, stainless steel, nickel, nichrome, titanium gold, silver, brass, or any alloy thereof. 
     
     
         4 . The system of  claim 1 , wherein the elongate conductor is coated with at least one of protective layer and insulating layer. 
     
     
         5 . The system of  claim 4 , wherein the protective layer comprises PTFE, nylon, silicone, polyethylene, polyurethane, latex, polyimide, BoPET, or any combination thereof. 
     
     
         6 . The system of  claim 1 , wherein the elongate conductor is configured for placement adjacent to a peripheral nerve, spinal nerve, brain-stem nerve, or brain neuron or other neuron or axon. 
     
     
         7 . The system of any one of  claims 1  to  6 , wherein the elongate conductor comprises a cylindrical shape with a diameter and a length, wherein the diameter is less than the length. 
     
     
         8 . The system of  claim 7 , wherein the elongate conductor comprises a wire segment or strands of wire segments. 
     
     
         9 . The system of any one of  claims 1  to  8 , wherein the elongate conductor is injected into the body through a guiding tube. 
     
     
         10 . The system of  claim 9 , wherein the guiding tube comprises a needle of a syringe. 
     
     
         11 . The system of  claim 1 , wherein the magnetic field generator comprises a coil, the coil comprising one or more coil windings of wire. 
     
     
         12 . The system of  claim 11 , further wherein the magnetic field generator is connected in parallel with a capacitor such that a stimulation signal is a portion in time of a resonance between the coil and the capacitor. 
     
     
         13 . The system of  claim 12 , wherein the parallel capacitor and coil are configured to be activated by a DC power supply on one side and a switch to ground on the other side, wherein a time period between the switch opening and switch closing determines the portion of the resonance that becomes one or more stimulation pulse or pulses. 
     
     
         14 . The system of  claim 13 , wherein the switch is a combination of a transistor and a rectifier and a switching action is configured to occur by turning the transistor on or off by applying a voltage to a gate or a base of the transistor. 
     
     
         15 . The system of any one of  claims 12 - 14 , wherein the switching action is configured to open at a beginning of a first full resonant cycle and close prior to an end of the first cycle, at the end of the cycle, at an end of multiple cycles, or within a later cycle. 
     
     
         16 . The system of  claim 14  or  15 , wherein the switch is configured to turn off the gate or base of the transistor just prior to a series of decaying resonant pulses and then turned on to build up the current in the stimulator prior to the next decaying series to save electrical energy consumed by current in the coil between pulse series. 
     
     
         17 . The system of  claim 12 , wherein the parallel capacitor and coil are activated by an H driver with four switches. 
     
     
         18 . The system of  claim 17 , wherein each switch comprises a transistor and a rectifier. 
     
     
         19 . The system of  claim 17  or  18  wherein two of the four switches are configured to open and the other two switches are configured to close at the beginning of a first half of a resonant cycle and the opposite is configured to occur at the end of a second half of the resonant cycle. 
     
     
         20 . The system of any one of  claims 1 - 19 , wherein the magnetic field generator comprises a stimulator coil, the stimulator coil comprising a material with high magnetic permeability configured to contain the fringe fields. 
     
     
         21 . The system of  claim 20 , wherein the material with high magnetic permeability comprises rigid or flexible ferrite, steel or iron. 
     
     
         22 . The system of  claim 20 , wherein the coil further comprises a conducting ferromagnetic material that reduces the amplitude of subsequent resonant pulses relative to the prior pulses. 
     
     
         23 . The system of  claim 22 , wherein the material comprises iron, cobalt, nickel, steel, or an alloy or other combination thereof. 
     
     
         24 . The system of  claim 11 , wherein the one or more coil windings are in a plane or multiple adjacent planes. 
     
     
         25 . The system of  claim 11  or  24 , wherein the one or more coil windings comprise magnet wire. 
     
     
         26 . The system of  claim 11  or  24 , wherein the one or more coil windings comprise metal deposited on a layered substrate. 
     
     
         27 . The system of  claim 26 , wherein the substrate is rigid. 
     
     
         28 . The system of  claim 27 , wherein the substrate comprises FR-4 glass-reinforced epoxy laminate, glass, or hard plastic. 
     
     
         29 . The system of  claim 26 , wherein the substrate is flexible. 
     
     
         30 . The system of  claim 29 , wherein the substrate comprises polyimide, BoPET, polyethylene, polyurethane, nylon, or PTFE. 
     
     
         31 . The system of  claim 1 , further comprising one or more of a microprocessor, rechargeable battery, user interface, physician interface, nurse interface, data storage, and network connection. 
     
     
         32 . The system of  claim 31 , wherein the network interface is configured to monitor or control the stimulator by a computer, by the user or by a professional or to gather data or statistics therefrom. 
     
     
         33 . The system of  claim 1 , wherein the elongate conductor comprises a monolithic body. 
     
     
         34 . The system of  claim 1 , wherein the elongate conductor lacks a battery. 
     
     
         35 . The system of  claim 1 , wherein the elongate conductor lacks feedback circuitry. 
     
     
         36 . The system of  claim 1 , wherein the elongate conductor lacks power management circuitry. 
     
     
         37 . The system of  claim 1 , wherein the elongate conductor comprises a discrete metal wire with a diameter of less than 100 microns. 
     
     
         38 . The system of  claim 1 , wherein the elongate conductor comprises a first end, a second end, a body therebetween, and has a length of 10 mm or less from the first end to the second end. 
     
     
         39 . The system of  claim 38 , wherein neither the first end, the second end, or the body is connected to another conductor. 
     
     
         40 . A method of treating a condition, comprising:
 identifying a patient with one or more implanted elongate conductors;   placing a coil of an external magnetic field generator again a surface of a treatment site of the patient; and   applying a magnetic field to the one or more implanted elongate conductors to generate therapeutic neural stimulation.   
     
     
         41 . The method of  claim 40 , further comprising activating the magnetic field generated to, modulate, increase or decrease action potential activity at the treatment site. 
     
     
         42 . The method of  claim 40  or  41 , wherein the action potential activity are located in neurons in the brain, sensory system, or neuromuscular system. 
     
     
         43 . The method of any one of  claims 40  to  42 , used in the treatment of a pain disorder, mental disorder, sensory disorder, or muscular disorder. 
     
     
         44 . The method of  claim 43 , wherein the pain disorder is due to amputation, neuropathy, nerve damage, or injury. 
     
     
         45 . The method of  claim 43  wherein the mental disorder is depression, Huntington's disease, Alzheimer's disease, dementia, anxiety, insomnia, post-traumatic stress disorder, or panic attacks. 
     
     
         46 . The method of  claim 40 , further comprising generating the magnetic field using less than 100 peak amps and 100 volts of peak voltage. 
     
     
         47 . A treatment device, comprising:
 a syringe body;   a sliding plunger located in the syringe body;   a needle attached to the syringe body; and   wherein at least one discrete elongate conductor located in the syringe body, wherein the syringe body and needle restrain the orientation of the at least one elongate conductor;   
       wherein the elongate conductor comprises a monolithic metal body with a diameter of less than 100 microns. 
     
     
         48 . The treatment device of  claim 47 , wherein the monolithic metal body has a length of less than 10 mm. 
     
     
         49 . A neuromodulation system, comprising:
 at least one elongate conductor with a length of less than ten millimeters and a transverse dimension to the length of less than one millimeter, configured for implantation adjacent or against a nerve, axon, or neuron; and   a magnetic field generator that is spaced apart from the at least one elongate conductor, and configured to generate an induced and concentrated electric field at the at least one elongate conductor.   
     
     
         50 . The neuromodulation system of  claim 49 , wherein the at least one elongate conductor is pre-loaded in an injection device and in a sealed sterile package. 
     
     
         51 . The neuromodulation system of  claim 50 , wherein the at least one elongate conductor is a plurality of elongate conductors positioned serially within the injection device. 
     
     
         52 . The neuromodulation system of any one of  claims 49  to  51 , wherein the magnetic field generator further comprises a rechargeable battery. 
     
     
         53 . The neuromodulation system of  claim 52 , wherein the magnetic field generator is located in a housing comprising adjustable straps, elastic bands, Velcro, buckles, adhesives, or pins, configured to attach the housing a location on a human body or in attire or pockets thereof worn by a human body. 
     
     
         54 . The neuromodulation system of  claim 53 , wherein the housing has a height relative to a skin surface at the location on the human body that is less than one centimeter. 
     
     
         55 . A method of treating a patient, comprising:
 inserting at least one elongate conductor against or adjacent to a nerve, axon, neuron or neural tissue, wherein the conductor has a length of less than ten millimeters and a transverse dimension to the length of less than one millimeter;   positioning a magnetic field generator at a location spaced away from the at least one elongate conductor; and   using the magnetic field generator to provide an induced and concentrated electric field to at least one elongate conductor.   
     
     
         56 . The method of  claim 55 , wherein the magnetic field generator is an ambulatory magnetic field generator comprising a housing with a plurality of magnetic coils, a driver circuit, and a rechargeable battery. 
     
     
         57 . The method of  claim 56 , wherein the plurality of magnetic coils has a net thickness of less than three centimeters. 
     
     
         58 . The method  claim 56 , wherein the location spaced away from the at least one elongate conductor is against a skin surface. 
     
     
         59 . The method of  claim 56 , further comprising maintaining the location of the magnetic field conductor using straps, elastic bands, Velcro, buckles, adhesives, pins, or pockets. 
     
     
         60 . A magnetic stimulation system, comprising an external coil stimulation system configured for use against a tissue surface of a patient, and to generate a therapeutic magnetic field during therapy using at least one of 100 peak amps or less of instantaneous current; and a power supply voltage of 100 peak volts or less. 
     
     
         61 . The magnetic stimulation system of  claim 59 , wherein the external coil stimulation system is configured with an amperage limit of 100 amps or less of instantaneous current. 
     
     
         62 . The magnetic stimulation system of  claim 59  or  60 , wherein the external coil stimulation system is configured with a voltage limit of 100 volts or less. 
     
     
         63 . The magnetic stimulation system of  claim 60 , wherein the external coil stimulation system is connected in parallel with a capacitor such that a stimulation signal is a portion in time of a resonance between the external coil stimulation system and the capacitor. 
     
     
         64 . The magnetic stimulation system of  claim 60 , wherein the parallel capacitor and coil are configured to be activated by a DC power supply on one side and a switch to ground on the other side, wherein a time period between the switch opening and switch closing determines the portion of the resonance that becomes one or more stimulation pulse or pulses. 
     
     
         65 . The magnetic stimulation system of  claim 64 , wherein the switch is a combination of a transistor and a rectifier and a switching action is configured to occur by turning the transistor on or off by applying a voltage to a gate or a base of the transistor. 
     
     
         66 . The magnetic stimulation system of any one of  claims 63  to  65 , wherein the switching action is configured to open at a beginning of a first full resonant cycle and close prior to an end of the first cycle, at the end of the cycle, at an end of multiple cycles, or within a later cycle. 
     
     
         67 . The magnetic stimulation system of  claim 65  or  66 , wherein the switch is configured to turn off the gate or base of the transistor just prior to a series of decaying resonant pulses and then turned on to build up the current in the stimulator prior to the next decaying series to save electrical energy consumed by current in the coil between pulse series. 
     
     
         68 . The magnetic stimulation system of  claim 60 , wherein the parallel capacitor and coil are activated by an H driver with four switches. 
     
     
         69 . The magnetic stimulation system of  claim 68 , wherein each switch comprises a transistor and a rectifier. 
     
     
         70 . The magnetic stimulation system of  claim 68  or  69  wherein a first two of the four switches are configured to open and a second two of the four switches are configured to close at the beginning of a first half of a resonant cycle and wherein the first two of the four switches are configured to close and the second two of the four switches are configured to open at the end of a second half of the resonant cycle.