Methods and circuitry for calibrating stimulation circuitry in an implantable stimulator device (ISD) is disclosed. The ISD can sense neural response to the stimulation, and use an algorithm to assess those responses and determine a therapeutic window for a particular stimulation parameter, such as amplitude. Stimulation circuitry in the ISD is programmed with information indicative of the determined therapeutic window, such as by programming a minimum and/or maximum current amplitude. As well as restricting operation of the stimulation circuitry to within the therapeutic amplitude window, such programming calibrates the stimulation circuitry and allows an expanded range of, or all of, amplitude values supported by the stimulation circuitry to be used, which allows the amplitude to be incremented in smaller current increments.

Methods and systems for providing stimulation to a patient's brain using one or more electrode leads implanted in the patient's brain are described. The methods and systems help a clinician determine locations upon the lead where stimulation is expected to provide the best therapeutic benefit and the least side effects. Different locations upon the lead are used to provide stimulation and for each stimulation location evoked potentials are recorded. The evoked potentials are associated with likely beneficial therapeutic stimulation. Signals indicative of unwanted motor activity in the patient are also recorded for each of the stimulation locations. The recorded evoked potential signals and motor signals are used to determine stimulation locations that provide therapeutic benefit with minimal side effects. They can also be used to determine therapeutic windows for the potential stimulation locations.

A system for restoring muscle function to the lumbar spine to treat low back pain is provided. The system may include electrodes coupled to an implantable pulse generator (IPG), a handheld activator configured to transfer a stimulation command to the IPG, and an external programmer configured to transfer programming data to the IPG. The stimulation command directs the programmable controller to stimulate the tissue in accordance with the programming data. The system may include a software-based programming system run on a computer such that the treating physician may program and adjust stimulation parameters.

An implantable head-mounted unibody peripheral neurostimulation system is provided for implantation in the head for the purpose of treating chronic head pain, including migraine. The system may include an implantable pulse generator (IPG) from which multiple stimulating leads may extend sufficient to allow for adequate stimulation over multiple regions of the head, preferably including the frontal, parietal and occipital regions. A lead may include an extended body, along which may be disposed a plurality of surface metal electrodes, which may be sub-divided into a plurality of electrode arrays. A plurality of internal metal wires may run a portion of its length and connect the IPG's internal circuit to the surface metal electrodes. The IPG may include a rechargeable battery, an antenna, and an application specific integrated circuit. The IPG may be capable of functional connection with an external radiofrequency unit for purposes that may include recharging, diagnostic evaluation, and programming.

A detection circuit includes an open circuit detection branch and a current detection branch. The open circuit detection branch includes a comparator and a digital logic branch. A positive input terminal of the comparator is connected to one end of the sampling resistor adjacent to the stimulation source, a negative input terminal of the comparator is connected to one end of the sampling resistor facing away from the stimulation source, and an output terminal of the comparator is connected to the digital logic branch. The current detection branch includes an amplifier and a first switch. A negative input terminal of the amplifier is connected to the one end of the sampling resistor facing away from the stimulation source, an output terminal of the amplifier is connected to a control terminal of the first switch.

Neuromodulation of cranial nerves can be used to treat sleep or breathing disorders, among other diseases and disorders. A neuromodulation system can include a housing configured for implantation in an anterior cervical region of a patient, such as at or under a mandible of the patient, such as at least partially in one or more of a submental triangle, a submandibular triangle, and a carotid triangle. The system can include an electrode lead coupled to the housing, and the electrode lead can include an electrode configured to be disposed at or near a cranial nerve target in the patient. The system can be configured to generate electrical neuromodulation signals for delivery to the cranial nerve target using the electrode.

Passive tissue biasing circuitry in an Implantable Pulse Generator (IPG) is disclosed to facilitate the sensing of neural responses by holding the voltage of the tissue to a common mode voltage (Vcm). The IPG's conductive case electrode, or any other electrode, is passively biased to Vcm using a capacitor, as opposed to actively driving such electrode to a prescribed voltage using a voltage source. Once Vcm is established, voltages accompanying the production of stimulation pulses will be referenced to Vcm, which eases neural response sensing. An amplifier can be used to set a virtual reference voltage and to limit the amount of current that flows to the case during the production of Vcm. Circuitry can be used to monitor the virtual reference voltage to enable sensing neural responses, and to set a compliance voltage for the current generation circuitry.

Synchronized stimulation of cardiac tissue can be implemented by implanting two or more rectifier-based AM receivers into different positions within a subject's heart. Each receiver is tuned to a different frequency, and generates an output signal that is capable of stimulating cardiac tissue when a signal at the corresponding tuned frequency arrives at the receiver. An AM transmitter can activate any given one of the receivers by transmitting a signal into the subject's body at the proper frequency. A controller controls the transmitter by commanding the transmitter to transmit pulses of AC at different frequencies at different times, so that when those pulses are received by the correspondingly-tuned receivers, each of the receivers will generate respective output signals that stimulate respective parts of the heart at respective times to promote improved cardiac performance.

A delivery system is disclosed having an implant retainer configured to releasably hold an implant unit and maintain the implant unit in a fixation location relative to target tissue in a subject's body during an implantation procedure. A first suture guide portion may be disposed on a first side of the implant retainer and configured to guide a suture needle during the implantation procedure. A second suture guide portion may be disposed on a second side of the implant retainer, opposite the first side, and configured to guide the suture needle after the suture needle exits the first suture guide portion.

A method of treating a mental disorder of a patient includes generating, by an implantable stimulator configured to be implanted beneath a skin surface of the patient, stimulation sessions at a duty cycle that is less than 0.05 and applying, by the implantable stimulator in accordance with the duty cycle, the stimulation sessions to a tissue location associated with the mental disorder. The duty cycle is a ratio of T3 to T4. Each stimulation session included in the stimulation sessions has a duration of T3 minutes and occurs at a rate of once every T4 minutes. The implantable stimulator is powered by a primary battery located within the implantable stimulator and having an internal impedance greater than 5 ohms.