Abstract: Described herein are implantable closed-loop neuromodulation devices, systems that includes such devices and an interrogator configured to emit ultrasonic waves that power the device, methods of using such devices and systems, and methods of modulating neural activity. The implantable device can include one or more curved members extending from a body. The curved members are configured to at least partially circumscribe a nerve, and include one or more electrode pads. The body includes an ultrasonic transducer configured to receive ultrasonic waves and convert energy from the ultrasonic waves into an electrical energy; and a computational circuit configured to receive a detection signal based on a detected electrophysiological signal, generate a stimulation signal based on the detection signal, and operate the electrode pads of to emit an electrical pulse to the nerve based on the stimulation signal.

Abstract: Described herein are methods for monitoring or modulating an immune system in a subject; treating, reducing or monitoring inflammation; monitoring blood pressure; treating hypertension; or administering or adjusting a therapy for inflammation or hypertension in a patient by electrically stimulating the splenic nerve or detecting splenic nerve activity using an implanted medical device. Also described herein are implantable medical devices for performing such methods. The implanted medical device includes an ultrasonic transducer configured to receive ultrasonic waves and convert energy from the ultrasonic waves into an electrical energy that powers the device, two or more electrodes in electrical communication with the ultrasonic transducer that are configured to electrically stimulate a splenic nerve or detect a splenic nerve activity, and optionally a splenic nerve attachment member.

Abstract: Method and system embodiments for discovering or tracking a device implantable in a subject using ultrasonic waves are described. The method for tracking the implantable device can include establishing a synchronization state with the implantable device, estimating a location of the implantable device, and determining whether to maintain or to adjust were an ultrasonic beam is being focused based on ultrasonic signal strength. The method for discovering an implantable device powered using ultrasonic waves can include emitting an ultrasonic beam to successively focus on a plurality of focal points, receiving ultrasonic backscatter corresponding to the ultrasonic beam focused on the focal point, and comparing the received ultrasonic backscatter with a predetermined pattern associated with the implantable device to be discovered to generate a score indicating how likely the ultrasonic backscatter comprises the predetermined pattern; and determining a location of the implantable device from based on the scores.

Abstract: Described herein is an implantable medical device that includes a body having one or more ultrasonic transducers configured to receive ultrasonic waves and convert energy from the ultrasonic waves into an electrical energy, two or more electrodes in electrical communication with the ultrasonic transducer, and a clip attached to the body that is configured to at least partially surround a nerve and/or a filamentous tissue and position the two or more electrodes in electrical communication with the nerve. In certain examples, the implantable medical device includes two ultrasonic transducers with orthogonal polarization axes. Also described herein are methods for treating incontinence in a subject by converting energy from ultrasonic waves into an electrical energy that powers a full implanted medical device, and electrically stimulating a tibial nerve, a pudendal nerve, or a sacral nerve, or a branch thereof, using the fully implanted medical device.

Abstract: Described herein are implantable device networks that include two or implantable devices configured to modulate neural activity in a subject. The network includes at least one implantable device that can detect a detection signal, such as an electrophysiological signal or a physiological condition. The network also includes a second implantable device configured to emit an electrical pulse based at least on information related to the detection signal. The implantable devices in the network can wirelessly communicate between each other, either directly or through an intermediate device.

Abstract: Described herein is an implantable medical device that includes a body having one or more ultrasonic transducers configured to receive ultrasonic waves and convert energy from the ultrasonic waves into an electrical energy, two or more electrodes in electrical communication with the ultrasonic transducer, and a clip attached to the body that is configured to at least partially surround a nerve and/or a filamentous tissue and position the two or more electrodes in electrical communication with the nerve. In certain examples, the implantable medical device includes two ultrasonic transducers with orthogonal polarization axes. Also described herein are methods for treating incontinence in a subject by converting energy from ultrasonic waves into an electrical energy that powers a full implanted medical device, and electrically stimulating a tibial nerve, a pudendal nerve, or a sacral nerve, or a branch thereof, using the fully implanted medical device.