Abstract: Apparatus for treating an intervertebral disc of a subject is provided. The apparatus includes at least three intra-pulposus exposed electrode surfaces, which are configured to be implanted within a nucleus pulposus of the disc, at different respective locations; and one or more extra-pulposus exposed electrode surfaces, which are configured to be implanted outside the nucleus pulposus, in electrical communication with the disc. Control circuitry is configured to (a) configure the intra-pulposus exposed electrode surfaces to be cathodes, and the one or more extra-pulposus exposed electrode surfaces to be one or more anodes, and (b) drive the intra-pulposus exposed electrode surfaces and the one or more extra-pulposus exposed electrode surfaces to electroosmotically drive fluid into the nucleus pulposus to increase pressure in the disc.

Abstract: A method for treating a herniated intervertebral disc is provided, the method including implanting an electrode mount crossing an annulus fibrosus of the herniated intervertebral disc of a subject, such that the electrode mount holds at least one intra-pulposus exposed electrode surface in place in a nucleus pulposus of the herniated intervertebral disc. Control circuitry is activated to treat disc herniation by creating an electric potential difference between the at least one intra-pulposus exposed electrode surface and one or more extra-pulposus exposed electrode surfaces implanted outside the nucleus pulposus in electrical communication with the herniated intervertebral disc. Other embodiments are also described.

Abstract: A method is provided for treating an intervertebral disc of a subject, the method including implanting at least one intra-pulposus exposed electrode surface in a nucleus pulposus of the intervertebral disc, and implanting one or more extra-pulposus exposed electrode surfaces outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry, while electrically coupled to the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces, is activated to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.

Abstract: A method is provided for treating an intervertebral disc of a subject, the method including implanting at least one intra-pulposus exposed electrode surface in a nucleus pulposus of the intervertebral disc, and implanting one or more extra-pulposus exposed electrode surfaces outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry, while electrically coupled to the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces, is activated to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.

Abstract: Apparatus is provided for treating an intervertebral disc of a subject, the apparatus including: at least one intra-pulposus exposed electrode surface, which is configured to be implanted in a nucleus pulposus of the intervertebral disc; and one or more extra-pulposus exposed electrode surfaces, which are configured to be implanted outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry is electrically coupled to the at least one intra-pulposus exposed electrode surface and one or more extra-pulposus exposed electrode surfaces. The control circuitry is configured to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.

Abstract: Apparatus (20) for treating an intervertebral disc (30) of a subject is provided. The apparatus (20) includes at least three intra-pulposus exposed electrode surfaces (40), which are configured to be implanted within a nucleus pulposus (42) of the disc (30), at different respective locations; and one or more extra-pulposus exposed electrode surfaces (44), which are configured to be implanted outside the nucleus pulposus (42), in electrical communication with the disc (30). Control circuitry (50) is configured to (a) configure the intra-pulposus exposed electrode surfaces (40) to be cathodes, and the one or more extra-pulposus exposed electrode surfaces (44) to be one or more anodes, and (b) drive the intra-pulposus exposed electrode surfaces (40) and the one or more extra-pulposus exposed electrode surfaces (44) to electroosmotically drive fluid into the nucleus pulposus (40) to increase pressure in the disc (30).

Abstract: Apparatus is provided for treating an intervertebral disc of a subject, the apparatus including: at least one intra-pulposus exposed electrode surface, which is configured to be implanted in a nucleus pulposus of the intervertebral disc; and one or more extra-pulposus exposed electrode surfaces, which are configured to be implanted outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry is electrically coupled to the at least one intra-pulposus exposed electrode surface and one or more extra-pulposus exposed electrode surfaces. The control circuitry is configured to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.

Abstract: A method is provided that includes implanting a first electrode in a cerebrospinal fluid (CSF)-filled space of a brain of a subject identified as at risk of or suffering from Alzheimer's disease. One or more second electrodes are implanted superficial to brain parenchyma of the subject, such that the brain parenchyma is spatially disposed between a ventricular system of the brain and the one or more second electrodes. Control circuitry is activated to drive the first and the one or more second electrodes to clear amyloid beta and/or tau protein from the brain parenchyma into the ventricular system by applying current between the first electrode and the one or more second electrodes using an average voltage of less than 1.2 V. Other embodiments are also described.

Abstract: Apparatus is provided that includes one or more intra-pulposus exposed electrode surfaces, and a support structure along which the one or more intra-pulposus exposed electrode surfaces are disposed. The support structure is configured to be implanted within a nucleus pulposus of an intervertebral disc of a subject, and to be shaped as a partial ring or a complete ring after implantation. The apparatus further includes one or more extra-pulposus exposed electrode surfaces, which are configured to be implanted outside the nucleus pulposus, in electrical communication with the disc. Control circuitry is provided, which is configured to: configure the intra-pulposus exposed electrode surfaces to be cathodes, and the one or more extra-pulposus exposed electrode surfaces to be one or more anodes, and drive the intra-pulposus exposed electrode surfaces and the one or more extra-pulposus exposed electrode surfaces to electroosmotically drive fluid into the nucleus pulposus. Other embodiments are also described.

Abstract: A method is provided that includes implanting a first electrode in a cerebrospinal fluid (CSF)-filled space of a brain of a subject identified as at risk of or suffering from Alzheimer's disease. One or more second electrodes are implanted superficial to brain parenchyma of the subject, such that the brain parenchyma is spatially disposed between a ventricular system of the brain and the one or more second electrodes. Control circuitry is activated to drive the first and the one or more second electrodes to clear amyloid beta and/or tau protein from the brain parenchyma into the ventricular system by applying current between the first electrode and the one or more second electrodes using an average voltage of less than 1.2 V. Other embodiments are also described.

Abstract: A method is provided that includes implanting (a) a parenchymal electrode in or in contact with an outer surface of brain parenchyma of a subject identified as at risk of or suffering from a disease, and (b) a cerebrospinal fluid (CSF) electrode in a CSF-filled space of a brain of the subject, the CSF-filled space selected from the group consisting of: a ventricular system and a subarachnoid space. A midplane treatment electrode is disposed in or over a superior sagittal sinus. Control circuitry is activated to drive the parenchymal electrode and the CSF electrode to drive a substance from the brain parenchyma into the CSF-filled space of the brain, and apply a treatment current between the CSF electrode and the midplane treatment electrode to drive the substance from the CSF-filled space of the brain to the superior sagittal sinus. Other embodiments are also described.

Abstract: A method is provided that includes implanting (a) a parenchymal electrode in or in contact with an outer surface of brain parenchyma of a subject identified as at risk of or suffering from a disease, and (b) a cerebrospinal fluid (CSF) electrode in a CSF-filled space of a brain of the subject, the CSF-filled space selected from the group consisting of: a ventricular system and a subarachnoid space. A midplane treatment electrode is disposed in or over a superior sagittal sinus. Control circuitry is activated to drive the parenchymal electrode and the CSF electrode to drive a substance from the brain parenchyma into the CSF-filled space of the brain, and apply a treatment current between the CSF electrode and the midplane treatment electrode to drive the substance from the CSF-filled space of the brain to the superior sagittal sinus. Other embodiments are also described.

Abstract: Apparatus is provided that includes a parenchymal electrode, configured to be implanted in brain parenchyma of a subject identified as at risk of or suffering from a synucleinopathy; and a cerebrospinal fluid (CSF) electrode, configured to be implanted in a CSF-filled space of a brain of the subject, the CSF-filled space selected from the group consisting of: a ventricular system and a subarachnoid space. Control circuitry is configured to drive the parenchymal and the CSF electrodes to clear alpha-synuclein (aSyn) from the brain parenchyma into the CSF-filled space of the brain. Other embodiments are also described.

Abstract: Apparatus is provided including a surgical tool configured to be advanced distally within a body of a subject. The surgical tool is shaped to define a side-facing suction port at a distal portion of the surgical tool to facilitate drawing tissue through the suction port and into the surgical tool, and includes a slidable transparent shutter configured to be disposed over the suction port, and to be slidably removed from the suction port. A needle is configured to be slidably disposed within the surgical tool and configured to puncture the tissue while the tissue is in the surgical tool. Other applications are also described.

Abstract: Apparatus is provided that includes one or more intra-pulposus exposed electrode surfaces, and a support structure along which the one or more intra-pulposus exposed electrode surfaces are disposed. The support structure is configured to be implanted within a nucleus pulposus of an intervertebral disc of a subject, and to be shaped as a partial ring or a complete ring after implantation. The apparatus further includes one or more extra-pulposus exposed electrode surfaces, which are configured to be implanted outside the nucleus pulposus, in electrical communication with the disc. Control circuitry is provided, which is configured to: configure the intra-pulposus exposed electrode surfaces to be cathodes, and the one or more extra-pulposus exposed electrode surfaces to be one or more anodes, and drive the intra-pulposus exposed electrode surfaces and the one or more extra-pulposus exposed electrode surfaces to electroosmotically drive fluid into the nucleus pulposus. Other embodiments are also described.

Abstract: A method is provided that includes positioning electrodes in or in contact with a head of a subject identified as in need of enhanced microglial cell activation. Control circuitry is activated to drive the electrodes to apply an electrical current to a brain of the subject in pulses having an average pulse duration of between 0.1 ms and 10 ms, and to configure the electrical current to enhance microglial cell activation for taking up amyloid beta or tau protein from brain parenchyma. The control circuitry is activated to apply the electrical current with an average amplitude of between 0.1 and 5 mA, or with an average voltage that results in between 0.1 and 5 mA current. Other embodiments are also described.

Abstract: A method is provided that includes positioning electrodes in or in contact with the head of a subject identified as in need of enhanced microglial cell activation. Control circuitry is activated to drive the electrodes to apply an electrical current to the brain of the subject, and to configure the electrical current to enhance microglial cell activation for taking up a substance from brain parenchyma. Other embodiments are also described.

Abstract: Apparatus (20) for treating an intervertebral disc (30) of a subject is provided. The apparatus (20) includes at least three intra-pulposus exposed electrode surfaces (40), which are configured to be implanted within a nucleus pulposus (42) of the disc (30), at different respective locations; and one or more extra-pulposus exposed electrode surfaces (44), which are configured to be implanted outside the nucleus pulposus (42), in electrical communication with the disc (30). Control circuitry (50) is configured to (a) configure the intra-pulposus exposed electrode surfaces (40) to be cathodes, and the one or more extra-pulposus exposed electrode surfaces (44) to be one or more anodes, and (b) drive the intra-pulposus exposed electrode surfaces (40) and the one or more extra-pulposus exposed electrode surfaces (44) to electroosmotically drive fluid into the nucleus pulposus (40) to increase pressure in the disc (30).

Abstract: Apparatus is provided including a surgical tool configured to be advanced distally within a body of a subject. The surgical tool is shaped to define a side-facing suction port at a distal portion of the surgical tool to facilitate drawing tissue through the suction port and into the surgical tool, and includes a slidable transparent shutter configured to be disposed over the suction port, and to be slidably removed from the suction port. A needle is configured to be slidably disposed within the surgical tool and configured to puncture the tissue while the tissue is in the surgical tool.

Abstract: A composition delivery source (200) is provided that includes (a) a chamber (202), which is shaped so as to define (A) one or more liquid ports (310) in fluid communication with an interior of the chamber (202), and (B) one or more solid-liquid composition ports (312) in fluid communication with the interior of the chamber (202); (b) a solid-liquid composition delivery tube (314) in fluid communication with at least one of the one or more solid-liquid composition ports (312); (c) a mixing tube (316) in fluid communication with at least one of the one or more liquid ports (310) and at least one of the one or more solid-liquid composition ports (312); and (d) a liquid-supply tube (318) in fluid communication with at least one of the one or more liquid ports (310). A pump unit (201) includes one or more pumps (223), which are arranged to cause flow in the mixing tube (316) during a mixing activation state (342), and to cause flow in the liquid-supply tube (318) during a particle-delivery activation state (344).