The present invention relates to an apparatus, system, and method for implantable therapeutic treatment of a patient.
Acute and chronic conditions such as pain, arthritis, sleep apnea, seizure, incontinence, and migraine are physiological conditions affecting millions of people worldwide. For example, sleep apnea is described as an iterated failure to respire properly during sleep. Those affected by sleep apnea stop breathing during sleep numerous times during the night. There are two types of sleep apnea, generally described in medical literature as central and obstructive sleep apnea. Central sleep apnea is a failure of the nervous system to produce proper signals for excitation of the muscles involved with respiration. Obstructive sleep apnea (OSA) is cause by physical obstruction of the upper airway channel (UAW).
Current treatment options range from drug intervention, non-invasive approaches, to more invasive surgical procedures. In many of these instances, patient acceptance and therapy compliance is well below desired levels, rendering the current solutions ineffective as a long term solution.
Implants are a promising alternative to these forms of treatment. For example, pharyngeal dilation via hypoglossal nerve (XII) stimulation has been shown to be an effective treatment method for OSA. The nerves are stimulated using an implanted electrode. In particular, the medial XII nerve branch (i.e., in. genioglossus), has demonstrated significant reductions in UAW airflow resistance (i.e., increased pharyngeal caliber). Stimulation of the vagus nerve is thought to affect some of its connections to areas in the brain prone to seizure activity. Sacral nerve stimulation is an FDA-approved electronic stimulation therapy for reducing urge incontinence. Stimulation of peripheral nerves may help treat arthritis pain.
While electrical stimulation of nerves has been experimentally shown to remove ameliorate certain conditions, e.g., obstructions in the UAW, current implementation methods typically require accurate detection of an condition (e.g., a muscular obstruction of an airway), selective stimulation of a muscle or nerve, and a coupling of the detection and stimulation components. Additionally, attempts at selective stimulation have to date required multiple implants with multiple power sources, and the scope of therapeutic efficacy has been limited. A need therefore exists for an apparatus and method for programmable and/or selective neural stimulation of multiple implants or contact excitation combinations using a single controller power source.
The present invention relates to an apparatus, system, and method for selective and programmable implants for the therapeutic treatment of obstructive sleep apnea.
In one embodiment, an implantable RFID-enabled micro-electronic neurostimulator includes an implantable RFID-enabled micro-electronic neurostimulator system having an implant subsystem including one or more of a) an array of electrodes, where at least one electrode pair contacts a nerve, b) a multiplexer digital to analog signal converter, and c) a RFID based control and stimulation chip. The system also includes an external subsystem having one or more of a controller, an RF interface and an optional power source.
In certain embodiments, the present invention is suitable for the stimulation of certain nerves to treat conditions which may be ameliorated by stimulation of a nerve. Such nerves and conditions include, but are note limited to multiple small peripheral nerves for treatment of arthritis pain; deep brain/cortical stimulation for treatment of one or more of essential tremor, Parkinson's disease, dystonia, depression, tinnitus, epilepsy, stroke pain, and obsessive compulsive disorder; sacral nerve stimulation for the treatment of incontinence, pelvic pain and sexual dysfunction; vagus nerve stimulation for treatment of epilepsy and/or depression; peripheral nerve stimulation for treatment of chronic pain; spinal cord stimulation for treatment of one or more of chronic pain, angina pain, and peripheral vascular disease pain; cochlear nerve stimulation for treatment of profound deafness; pulmonary nerve stimulation for treatment of respiratory support; gastric nerve stimulation for treatment of one or more of obesity, gastroparesis, and irritable bowel syndrome; and occipital nerve stimulation for treatment of headaches/migraine and/or traumatic brain injury.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention. In the drawings:
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
One embodiment the present invention includes an external subsystem and an internal subsystem. In certain embodiments, the external subsystem can include one or more of (1) a controller, (2) an external RF interface, and (3) an optional power source. The internal subsystem may include an implant. In certain embodiments, the implant can include one or more of (1) a neural interface which can include an array of electrodes where at least one electrode contacts a nerve, is placed in close proximity to a nerve, or wraps around a nerve, (2) a core subsystem, and (3) an internal RF interface. In some embodiments, the neural interface may further include a digital to analog signal converter and a multiplexer. In some embodiments the core subsystem may include a microprocessor. The microprocessor may have a micrologic CPU and memory to store protocols selective to a patient. The microprocessor may be part of an integrated silicon package. In still further embodiments, the internal RF interface includes one or more of a transponder, internal antenna, modulator, demodulator, clock, and rectifier. The transponder can be passive or active. In some embodiments, one or more of a controller, external RF interface, and optional power source are positioned on the skin of a user/patient, typically directly over or in close proximity to, an implant.
In certain embodiments, the external subsystem controller is in the form of an earpiece or patch including any one or more of a controller, external RF interface, and optional power source, e.g., a battery, AC to DC converter, or other power source known to those skilled in the art. Still further embodiments include incorporation of the external subsystem 200 into a watch-like device for, e.g., the treatment of arthritic pain, or in a belt. In certain embodiments, the external subsystem sends and receives control logic and power using an external RF interface. In such embodiments, the external subsystem can further include one or more of a crypto block, data storage, memory, recording unit, microprocessor, and data port. In some embodiments the microprocessor may have a micrologic CPU and memory to store protocols selective to a patient. The microprocessor may be part of an integrated silicon package.
The system of the present invention can be used to treat a number of conditions by stimulating nerves which are associated with treating a condition. Stimulation can be such that the stimulus is transmitted by a nerve, or stimulation can be such that nerve transmission in a nerve is blocked by nerve depolarization. Some non-limiting examples of treatment by nerve stimulation include multiple small peripheral nerves for treatment of arthritis pain; deep brain/cortical stimulation for treatment of one or more of essential tremor, Parkinson's disease, dystonia, depression, tinnitus, epilepsy, stroke pain, and obsessive compulsive disorder; sacral nerve stimulation for the treatment of incontinence, pelvic pain and sexual dysfunction; vagus nerve stimulation for treatment of epilepsy and/or depression; peripheral nerve stimulation for treatment of chronic pain; spinal cord stimulation for treatment of one or more of chronic pain, angina pain, and peripheral vascular disease pain; cochlear nerve stimulation for treatment of profound deafness; pulmonary nerve stimulation for treatment of respiratory support; gastric nerve stimulation for treatment of one or more of obesity, gastroparesis, and irritable bowel syndrome; and occipital nerve stimulation for treatment of headaches/migraine and/or traumatic brain injury.
Each of the components of various embodiments of the claimed invention is described hereafter. In certain embodiments, the present invention is an open loop system. In other embodiments the present invention is a closed loop system. The components of the embodiments can be rearranged or combined with other embodiments without departing from the scope of the present invention.
The Internal Subsystem
In certain embodiments, the internal subsystem includes an implant, which includes one or more of (1) a core subsystem, (2) a neural interface, and (3) an internal RF interface. Certain embodiments of the implant components and component arrangements are described below.
Implant Components
The following paragraphs describe embodiments of the implant of the present invention, which includes one or more of a core subsystem, neural interface, and internal RF interface components.
The Core Subsystem
The Neural Interface
The right portion of
In the embodiment shown, the neural interface 160 receives power from RF waves received by the implant 105. In one embodiment, the digital to analog signal converter 164 uses the RF waves to power one or more capacitors 165, which may be located in the converter 164. In certain embodiments, the capacitors 165 are arranged in an array on a microfilm. These capacitors 165 store charges, which are used to generate analog burst pulses for delivery by the neural interface 160. In embodiments including a multiplexer 166, the multiplexer 166 may be used to deliver power to multiple capacitors 165, and can be used to deliver power to multiple electrodes 161 in the neural interface 160. In still further embodiments, the multiplexer 166 is programmable.
In certain embodiments, the neural interface 160 is physically located on the opposite side of the printed circuit board 130 to which the core subsystem 140 is attached. In other embodiments, the one or more electrodes 161 are physically separated from the core subsystem 140 by the printed circuit board 130. Each electrode 161 connects to the core subsystem 140 through wires 133 (e.g., traced wires ) on the printed circuit board 130. This layered approach to separating the core subsystem 140 from the electrodes 161 has significant benefits in the bio-compatible coating and manufacturing of the implant. By minimizing the area exposed to the HGN, the bio-compatible coating is only required in the area surrounding the exposed parts of the electrodes 161.
In certain embodiments, the electrodes 161 may be manufactured with a biocompatible material coating. In other embodiments, the electrodes may include embedded platinum contacts spot-welded to a printed circuit board 130 on the implant 105. The electrodes 161 may be arrayed in a matrix, with the bottoms of the electrodes 161 exposed for contact to the HGN. Since the electrodes 161 attach to the top portion of the core subsystem 140 through leads on the printed circuit board, there is no need for wire-based leads attached to the contact points, allowing for miniaturization of the electrodes 161.
The upper number of electrodes is determined by the space available for the implant, which varies by indication (e.g., arthritis). In one embodiment, the present invention includes one or more electrodes in contact with a nerve. As shown in
The Internal RF Interface
The left portion of
The internal RF interface 150 operates according to the principle of inductive coupling. In an embodiment, the present invention exploits the near-field characteristics of short wave carrier frequencies of approximately 13.56 MHz. This carrier frequency is further divided into at least one sub-carrier frequency. In certain embodiments, the present invention can use between 10 and 15 MHz. The internal RF interface 150 uses a sub carrier for communication with an external RF interface 203, which may be located in the controller 205. The sub-carrier frequency is obtained by the binary division of the external RF interface 203 carrier frequency. In the embodiment shown, the internal RF interface 150 is realized as part of a single silicon package 170. The package 170 may further include a chip 145 which is a programmable receive/transmit RF chip.
In certain embodiments, the internal RF interface 150 also includes a passive RFID transponder 156 with a demodulator 158 and a modulator 157. The transponder 156 uses the sub carrier to modulate a signal back to the external RF interface 203. The transponder 156 may further have two channels, Channel A and Channel B. Channel A is for power delivery and Channel B is for data and control. In certain embodiments, the transponder 156 may employ a secure full-duplex data protocol.
The internal RF interface 150 further includes an inductive coupler 152, an RF to DC converter 155, and an internal antenna 151. In certain embodiments, the internal antenna 151 includes a magnetic component. In such embodiments, silicon traces may be used as magnetic antennas. In other embodiments, the antenna may be a high Q coil electroplated onto a silicon substrate, and can vary in size according to the amount of power required in treating an indication and the required distance from the controller. A parallel resonant circuit 153 may be attached to the internal antenna 151 to improve the efficiency of the inductive coupling. The internal antenna 151 may be realized as a set of PCB traces 133 on the implant 105. Size of the antenna traces is chosen on the basis of power requirements, operating frequency, and distance to the controller 205. Both the internal RF interface 150 and the core subsystem microprocessor 141 are powered from an RF signal received by the internal antenna 151. A shunt regulator 154 in the resonant circuit 153 keeps the derived voltage at a proper level.
Internal Subsystem Design
In the present invention it is important to note that the size of the internal subsystem can vary, and can have any shape. For example, for the treatment of arthritic pain, the internal subsystem 100 can be designed such that multiple implants 105 respond to the same secured RF signal from a single external subsystem 200. Similarly, the implant 105 can be small enough and properly shaped to facilitate placement at or near or on a nerve by injecting the implant 105.
Implant Subsystem Arrangement
The implant 105 may be located on any suitable substrate and may be a single layer or multi-layer form.
In certain embodiments, implant components are layered on a nerve. This alleviates the need for complex wiring and leads. In
In the embodiment shown in
In other embodiments, such as the one shown in
The implant 105 may further include an isolation layer 112 (
External Subsystem
In certain embodiments, the external subsystem 200 may include one or more of (1) a controller, (2) an external RF interface and (3) an optional power source. An embodiment of an external subsystem 200 including these elements is shown in
The Controller
In certain embodiments, the controller may further include one or more of an external RF interface 203 having RF transmit and receive logic, a data storage 206 that may be used to store patient protocols, an interface 202 (e.g., a USB port), a microprocessor 203, an external antenna (not shown), a functionality to permit the controller 205 to interface with a particular implant 105, and an optional power source 215. In certain embodiments, the controller electronics can be either physically or electromagnetically coupled to an antenna. The distance between the external RF interface antenna and the implant 105 may vary with indication. In certain embodiments, distance is minimized to reduce the possibility of interference from other RF waves or frequencies. Minimizing the distance between the external antenna and the implant 105 provides a better RF coupling between the external and internal subsystems 200/100, further reducing the possibility of implant activation by a foreign RF source. An encrypted link between the external and internal subsystems 200/100 further reduces the possibility of implant activation by foreign RF. In other embodiments, one or more of the internal antenna 151 and external antenna are maintained in a fixed position. Potential design complexity associated with internal RF interface antenna 151 orientation is minimized through the ability to position the external RF interface antenna in a specific location (e.g., near the patient's ear). Even if the patient moves, the internal RF interface antenna 151 and controller 205 remain coupled.
In certain other embodiments, the controller 205 also serves as (1) a data gathering and/or (2) programming interface to the implant 105. The controller 205 has full control over the operation of the implant 105. It can turn the implant 105 on/off,. and may be paired to the implant 105 via a device specific ID, as described herein below with respect to use of the implant 105 and controller 205 of the present invention. In still further embodiments, the controller microprocessor 204 calculates stimulus information. The stimulus information is then communicated to the implant 105. The implant 105 then provides a calculated stimulus to a nerve. In another embodiment, the controller 205 preloads the implant 105 with an algorithmic protocol for neural stimulation and then provides power to the implant 105.
External RF Interface
In the embodiment shown in
In an embodiment, the external RF interface 203 operates at a carrier frequency of about 13.56 MHz. In certain embodiments, the external RF interface 203 can operate between 10 and 15 MHz. This carrier frequency is further divided into at least one sub-carrier frequency. The sub-carrier frequency is obtained by the binary division of the external RF interface 203 carrier frequency. The external RF interface 203 uses the sub carrier for communication with the internal RF interface 150. The external RF interface transponder 208 (not shown) uses the sub carrier to modulate a signal to the internal RF interface 150. The transponder 208 (not shown) may further have two channels, Channel A and Channel B. Channel A is for power delivery and Channel B is for data and control. The transponder 208 (not shown) may employ a secure full-duplex data protocol.
In certain embodiments, the external RF interface 203 may further include a demodulator 211 (not shown) and a modulator 210 (not shown). In still further embodiments, the external RF interface 203 further includes an external antenna. In certain embodiments, the external antenna includes a magnetic component. In such embodiments, silicon traces may be used as magnetic antennas. The external antenna may be realized as a set of PCB traces. In other embodiments, the antenna may be a high Q coil electroplated onto a silicon substrate. Size of the antenna traces is chosen on the basis of power requirements, operating frequency, and distance to the internal subsystem 100. Antenna size may also be chosen according to the indication to be treated. In certain embodiments, the external antenna may transmit the power received by internal subsystem 100. In certain other embodiments, the external antenna may be larger, and have a higher power handling capacity than the internal antenna 151, and can be realized using other antenna embodiments known by those skilled in the art.
In certain embodiments, the external subsystem 200 is loosely coupled to an optional power source 215. In one embodiment, the controller power source 215 is not co-located with the external RF interface antenna. The external power source 215 may be in one location, and the external RF interface 203 and optionally the controller 205 are in a second location and/or third location. For example, each of the power source 215, controller 205 and external RF interface 203 can be located in difference areas. In one embodiment, the power source 215 and the controller 205 and the external RF interface 203 are each connected by one or more conductive members, e.g. a flexible cable or wire. Additionally, in certain embodiments, the controller 205 and optional power source 215 may be co-located, and the external RF interface 203 may be located elsewhere (i.e., loosely coupled to the controller 205). In such embodiments, the external RF interface 203 is connected to the controller 205 by a flexible cable or wire.
Since the power source 215 may be separately located from the controller 205 and/or external RF interface antenna, a larger power source 215 can be externally located but positioned away from the nerve that requires stimulation. Further, to reduce wasted power, a larger external RF interface antenna can be used. This provides the advantage of less discomfort to a user and therefore enhances patient compliance.
Such embodiments can also provide power to 2, 3, 4, 5 or more loosely coupled external RF interfaces 203. Thus, each external RF interface 203 can be positioned at or near the site of an implant 105 without the need for a co-located power source 215. In certain embodiments, each external RF interface 203 draws power from a single power source 215, and thus a single power source 215 powers a plurality of implants 105. Of course, the amount of power provided to each implant 105 will vary by indication and distance between the external RF interface 203 and the implant 105. The greater the distance between the external RF interface 203 and the implant 105, the greater the power level required. For example, a lower power is generally required to stimulate peripheral nerves, which are closer to the surface of the skin. As apparent to one of skill in the art, the power received at the implant 105 must be high enough to produce the desired nerve stimulus, but low enough to avoid damaging the nerve or surrounding tissue.
The external RF interface 203 may further include a programmable receive/transmit RF chip, and may interface with the controller crypto unit 201 for secure and one-to-one communication with its associated implant 105. The external RF interface 203 includes a parameterized control algorithm, wherein the parameterized control algorithm compares the sensed information to a reference data set in real time. The algorithm may be included in the controller microprocessor 204. Depending upon the patient's size and severity of disease state, the algorithm will vary a number of parameters which include frequency, amplitude of the signal, number of electrodes involved, etc.
Interaction With Outside Information Sources
The external subsystem controller 205 may also interface with a computer. In some embodiments, the controller interface 202 is a built-in data port (e.g., a USB port). The built-in micro USB port serves as the interface to a physician's PC. The purpose of the PC interface is to tune (and re-tune) the implant system and transfer recorded data. Via the controller interface 202 a computer also transfer historical data recorded by the implant 105. The controller 205 may obtain and update its software from the computer, and may upload and download neural interface data to and from the computer. The software may be included in the controller microprocessor 204 and associated memory. The software allows a user to interface with the controller 205, and stores the patient's protocol program.
External Subsystem Design
The external subsystem 200 can be of regular or irregular shape.
Communication With the Implant as a Function of Design
The distance between the external RF interface antenna and the implant 105 may vary with indication. In certain embodiments, e.g., in an embodiment for treating sleep apnea, the distance between this contact area and the actual implant 105 on a nerve is 1 to 10 cm, typically 3 cm, through human flesh. This distance, along with the controller crypto unit 201 and the core subsystem crypto unit 142 in the implant 105, reduces potential interference from other RF signals. Minimizing the distance between the external antenna and the implant 105 provides a better RF coupling between the external and internal subsystems 200/100, further reducing the possibility of implant activation by a foreign RF source. An encrypted link between the external and internal subsystems 200/100 further reduces the possibility of implant activation by foreign RF. In other embodiments, one or more of the internal antenna 151 and external antenna are maintained in a fixed position. Potential design complexity associated with internal RF interface antenna 151 orientation is minimized through the ability to position the external RF interface antenna in a specific location (e.g., near the patient's ear). Even if the patient moves, the internal RF interface antenna 151 and controller 205 remain coupled.
Implant Power
In certain embodiments, the implant 105 is externally powered by near field RF waves, the RF waves are inductively converted to DC power, which powers the implant 105 and delivers electrical signals to selected elements of the neural interface 160. In one embodiment, the implant 100 uses between 0.1 to about 1 milliamps, preferably averaging about 0.5 milliamps of current and about 10 to 30 microwatts of power. In some embodiments, the near field RF waves are emitted from the controller 205. In certain embodiments, controller 205 can be powered by an optional power source 215, e.g., a battery. In certain embodiments, the battery can be rechargeable battery. In other embodiments, the optional power source 215 is AC to DC converter, or other power sources known to those skilled in the art.
Implant and Controller Security
In certain embodiments, the controller 205 identifies the patient's unique ID tag, communicates with and sends signals to the implant 105. In certain embodiments, a controller crypto unit 201 may be installed to ensure that communication between the controller 205 and the implant 105 is secure and one-to-one. The controller crypto unit 201 may include the implant's unique ID tag.
In particular, the implant 105 may have a unique ID tag, which the controller 205 can be programmed to recognize. A controller microprocessor 204 confirms the identity of the implant 105 associated with the controller 205, thereby allowing setting of the patient's specific protocol. The setting may be accomplished using a computer interfaced with the controller 205 through an interface 202 on the controller 205.
More particularly, once the controller crypto unit 201 establishes a link with the core subsystem crypto unit 142, the controller 205 communicates a stimulation scenario to the core subsystem microprocessor 141. The controller 205 initiates a stimulation cycle by making a request to the core subsystem 140 by sending an encoded RF waveform including control data via the external RF interface 203. The core subsystem 140 selects a trained waveform from memory and transmits the stimulation waveform to the core subsystem microprocessor 141. Once the core subsystem microprocessor 141 receives the waveform, the core subsystem 140 generates a stimulating signal for distribution to the neural interface 160.
In certain embodiments, the controller 205 prevents self-activation or autonomous operation by the implant 105 by handshaking. Handshaking occurs during each communications cycle and ensures that security is maintained. This prevents other devices operating in the same frequency range from compromising operation of the implant 105. Implant stimulus will not commence unless an encrypted connection is established between the external RF interface 203 and the implant 105. This serves as an anti-tampering mechanism by providing the implant 105 with a unique ID tag. The external controller 205 is matched, either at the point manufacture or by a physician, to a particular ID tag of the implant 105, typically located in an EPROM of the implant 105. In certain embodiments, the EPROM may be included in the core subsystem microprocessor 141. In other embodiments, the EPROM may be included in the controller microprocessor 204. This prevents alien RF interference from ‘triggering’ activation of the implant 105. While arbitrary RF sources may provide power to the implant 105, the uniquely matched controller 205 establishes an encrypted connection before directing the implant 105 to commence stimulus, thereby serving as a security mechanism.
Implant and Controller Positioning
Prior to implantation of the present invention for the treatment of a condition, the patient is first diagnosed as being a suitable candidate for such treatment. For example, with respect to sleep apnea, patients are diagnosed in a sleep lab and an implant 105 is prescribed for their specifically diagnosed condition. Once diagnosis is complete, the implant 105 is implanted in the patient's body, typically on or in the vicinity of a nerve. In certain embodiments, the implant 105 is implanted on the HGN. In such embodiments, the implant 105 may be implanted below the ear unilaterally at the sub-mandibular triangle, encasing the hypoglossal nerve. In treatment of incontinence the implant 105 is placed on or near the sacral nerve, and in treatment of arthritis, implants 105 are placed near the peripheral nerves transmitting pain.
Once implanted, the implant 105 is used to stimulate the nerve. Stimulation of a fascicle or axon can act to maintain nerve activity. Hence in certain embodiments, the present invention can maintain muscular tone (e.g., in the tongue, thereby preventing apnea). Therefore, in certain embodiments, controller 205, described in more detail above, activates implant 105 to stimulate neural activity to ameliorate the negative physiological impact associated an indication.
In embodiments where the device is implanted in a manner to stimulate the HGN, the implant 105 delivers tone to the tongue. Maintaining tongue muscle tone stops the tongue from falling back and obstructing the upper airway. In embodiments where the device is implanted to stimulate the sacral nerve, the controller 205 sends small electrical impulses to the sacral nerve, acting as a bladder toner, reducing or eliminating the patient's urge incontinence. In other embodiments, the implant subsystem is implanted in a manner so as to provide analgesia to a patient by using stimulation to suppress transmission of nerve impulses from a nerve by depolarizing the nerve using bi-phasic stimulation. The stimulation may be provided continuously during sleep hours, or upon preprogrammed customer-specific intervals. The implant 105 may also sense and record neural activity.
Implant and Controller Treatments
The desired treatment is determined by assessing a patient's needs and measuring a patient's needs against predetermined stimulation protocols. The neural interface 160 stimulation protocols are measured until a desired response is achieved. Once a desired stimulation level is achieved, those protocols may be programmed into a controller 205. Stimulation may be programmed for delivery in an open loop or closed loop. After the controller 205 is programmed, the patient activates the controller 205 at bed time or at desired intervals. In the case of arthritic pain or other pain, the patient can activate the controller on an “as needed” basis. This electrical stimulation provides a signal to the targeted nerve and starts the treatment. Upon completion of one treatment cycle, the duration of which is determined in the tuning phase of the implantation procedure, described above, the core subsystem 140 can report completion back to the controller 205 via RF communication, and optionally goes to an idle state until receiving another set of instructions.
Typically, the controller is programmed post-implantation at the time of customization. The patient's muscle activity or sensed pain level is measured against the stimulation parameters. Multi-contact design of the electrodes 161 (
In certain embodiments, controller 205 can also determine when treatment is required, and stimulate a targeted nerve based on that determination. In order to make such a determination, controller 205 can include one or more sensors that generate signals as a function of the activity and/or posture of the patient. In other embodiments the patient may enter an input into the controller 205 telling it to commence treatment. However, as noted above, controller 205 can be activated by a user and then function in a manner such that the implant is continuously active until the patient manually deactivates the controller by pressing a button on the controller 205, or by moving the controller 205 out of range of the implant. In other embodiments, the controller 205 can be programmed to activate and deactivate an implant 105 at programmed intervals.
This electrical stimulation provides a signal to the nerve or nerves of interest and starts the treatment of the patient's condition. Upon completion of one cycle, the duration of which is determined in the tuning phase of the implantation procedure, described above, the core subsystem 140 can report completion back to the controller 205 via RF communication, and optionally goes to an idle state until receiving another set of instructions. Non-limiting examples of treatment programs are provided below.
Sleep Apnea
Incontinence
Stimulation may be programmed for delivery in an open loop or closed loop at a suitable frequency. In certain embodiments, a stimulation frequency of about 5 to 25 Hz is used, preferably 15 Hz. Stimulation may also be delivered in pulses of 0.5 to 3 mA, with pulse widths of about 100 to 300 microseconds, more typically 210 microseconds. Although any suitable pulse width can be used, preferred pulses are at a width that simultaneously prevent nerve damage and reduce or eliminate corrosion of neural interface electrodes. After the controller 205 is programmed, the patient activates the controller 205 when the urge to void is felt, at bed time, or at desired intervals. The embodiment in
Seizures
Vagus nerve stimulation may be programmed for delivery in an open or closed loop. In certain embodiments, a stimulation frequency of about 100 to 300 Hz is used, preferably 200 Hz. Stimulation is delivered in pulses of 3 to 10 mA, typically 7 mA. In certain embodiments, pulses are applied in bursts of 10 to 30, preferably 20 pulse bursts, with burst durations of 150 to 350 microseconds, typically 95 microseconds.
Although any suitable pulse width can be used, preferred pulses are at a width that simultaneously prevents nerve damage and reduces or eliminates corrosion of neural interface electrodes. The controller 205 may be programmed to provide stimulation constantly, or at predetermined intervals. In other embodiments, the patient activates the controller 205 to provide stimulation prior to the onset of a seizure.
Arthritis
The controller 205 is multiplexed and/or networked to the internal RF interface antennas 151 of multiple implants 105. In the embodiment shown, a network of multiple implants 105 is controlled and powered by a single external controller 205. In other embodiments, multiple controllers 205 power and control multiple implants 105. The number and location of controllers 205 and implants 105 is exemplary only, and not limited to what is shown in the figure.
In certain embodiments the controller 205 is in a patch (
Other embodiments of the apparatus and methods described can be used in the present invention. Various alternatives, substitutions and modifications for each of the embodiments and methods of the invention may be made without departing from the scope thereof, which is defined by the following claims. All references, patents and patent applications cited in this application are herein incorporated by reference in their entirety.
This application claims priority to U.S. Provisional Applications 60/774,039, 60/774,040, and 60/774,041 filed on Feb. 16, 2006, all of which are expressly incorporated herein by reference in their entirety.
Number | Date | Country | |
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60774039 | Feb 2006 | US | |
60774040 | Feb 2006 | US | |
60774041 | Feb 2006 | US |