Implantable medical devices (IMD), such as but not limited to leadless cardiac pacemakers (LCP), subcutaneous implantable cardioverter defibrillators (SICD), transvenous implantable cardioverter defibrillators, neuro-stimulators (NS), implantable monitors (IM), may be configured to communicate with each other. In some cases, a first IMD may transmit instructions to a second IMD. In order to improve the chances of a successfully received transmission, the first IMD may transmit the instructions several times during a particular time frame, such as during a single heartbeat. If the second IMD receives the message more than once, the second IMD recognizes that the messages were redundant and acts accordingly.

Described herein is an implantable device having a sensor configured to detect an amount of an analyte, a pH, a temperature, strain, or a pressure; and an ultrasonic transducer with a length of about 5 mm or less in the longest dimension, configured to receive current modulated based on the analyte amount, the pH, the temperature, or the pressure detected by the sensor, and emit an ultrasonic backscatter based on the received current. The implantable device can be implanted in a subject, such as an animal or a plant. Also described herein are systems including one or more implantable devices and an interrogator comprising one or more ultrasonic transducers configured to transmit ultrasonic waves to the one or more implantable devices or receive ultrasonic backscatter from the one or more implantable devices. Also described are methods of detecting an amount of an analyte, a pH, a temperature, a strain, or a pressure.

An implantable pulse generator (IPG) is disclosed having a plurality of electrode nodes, each electrode node configured to be coupled to an electrode to provide stimulation pulses to a patient's tissue. The IPG includes a digital-to-analog converter configured to amplify a reference current to a first current specified by first control signals; a first resistance configured to receive the first current, wherein a voltage across the first resistance is held to a reference voltage at a first node; a plurality of branches each comprising a second resistance and configured to produce a branch current, wherein a voltage across each second resistance is held to the reference voltage at second nodes; and a switch matrix configurable to selectively couple any branch current to any of the electrode nodes via the second nodes.

An implantable nerve stimulator is implanted in a patient near a nerve target. The implantable nerve stimulator has a plurality of electrodes through which stimulation is provided to the nerve target. The relative location of the nerve target and the electrodes may be determined by applying stimulation to the nerves via each of the electrodes, determining an effect of the stimulation for each of the electrodes, and mapping a location of the nerve relative to the electrodes based on the effect of the stimulation for each of the electrodes.

Devices, systems and methods are provided for treating post-operative symptoms following major surgery and/or for treating patients in critical or intensive care. A method includes positioning a contact surface of a device in contact with an outer skin surface of patient and applying an electrical impulse transcutaneously from the device through the outer skin surface of the patient to a vagus nerve in the patient for about 60 seconds to about 5 minutes. The electrical impulse is sufficient to modify the vagus nerve such that the symptoms are reduced. A stimulation protocol is provided that includes two or more doses administered per day for a period of time sufficient to relieve the symptoms. The doses may be administered before and after the patient's surgery, or while the patient is being treating in intensive care.

The present invention relates to methods for modulating bursts of oscillatory brain activity, such as sleep spindles, in a subject. The invention further relates to methods of improving memory or cognitive function in a subject and method of modulating or enhancing the frequency of occurrence, structure, amplitude, and/or synchronization of sleep spindles in a subject by detecting a burst of oscillatory brain activity in the subject and passing an oscillating current through the skull of the subject.

Numerous aspects of communication devices, methods, and systems are described in this application. One aspect is an apparatus comprising a plurality of energy generators arrangeable on or adjacent skin. Each energy generator of the plurality of energy generators may be operable to output a plurality of different energy types in a signal direction toward the skin. The plurality of energy generators may be operable to communicate with nerves associated with the skin when arranged on or adjacent the skin by outputting an energy signal in the signal direction with one or more energy types of the plurality of different energy types.

Techniques for modeling therapy fields for therapy delivered by medical devices are described. Each therapy field model is based on a set of therapy parameters and represents where therapy will propagate from the therapy system delivering therapy according to the set of therapy parameters. Therapy field models may be useful in guiding the modification of therapy parameters. As one example, a processor compares an algorithmic model of a therapy field to a reference therapy field and adjusts at least one therapy parameter based on the comparison. As another example, a processor adjusts at least one therapy parameter to increase an operating efficiency of the therapy system while substantially maintaining the modeled therapy field.

The invention comprises an elongated device adapted for insertion, including self-insertion, through the body, especially the skull. The device has at least one effector or sensor and is configured to permit implantation of multiple functional components through a single entry site into the skull by directing the components at different angles. The device may be used to provide electrical, magnetic, and other stimulation therapy to a patient's brain. The lengths of the effectors, sensors, and other components may completely traverse skull thickness (at a diagonal angle) to barely protrude through to the brain's cortex. The components may directly contact the brain's cortex, but from there their signals can be directed to targets deeper within the brain. Effector lengths are directly proportional to their battery size and ability to store charge. Therefore, longer angled electrode effectors not limited by skull thickness permit longer-lasting batteries which expand treatment options.

The present disclosure relates to methods, devices and systems used for the treatment of medical disorders via stimulation of the superficial elements of the trigeminal nerve. More specifically, cutaneous methods of stimulation of the superficial branches of the trigeminal nerve located extracranially in the face, namely the supraorbital, supratrochlear, infraorbital, auriculotemporal, zygomaticotemporal, zygomaticoorbital, zygomaticofacial, infraorbital, nasal and mentalis nerves (also referred to collectively as the superficial trigeminal nerve) are disclosed herein.