Electrical treatment of hydrocephalus
A method for treating hydrocephalus is provided, including disposing midplane treatment electrodes over a superior sagittal sinus of a brain, outside and in electrical contact with a skull of a head of a subject identified as suffering from hydrocephalus, and disposing lateral treatment electrodes between 1 and 12 cm of a sagittal midplane of the skull. The subject is treated by electroosmotically driving cerebrospinal fluid (CSF) out of a ventricular system of the brain via a subarachnoid space of the brain to the superior sagittal sinus, by activating control circuitry to apply one or more treatment currents between (a) one or more of the midplane treatment electrodes and (b) one or more of the lateral treatment electrodes. Other embodiments are also described.
1. A method comprising:
disposing midplane treatment electrodes over a superior sagittal sinus of a brain, outside and in electrical contact with a skull of a head of a subject identified as suffering from hydrocephalus;
disposing lateral treatment electrodes between 1 and 12 cm of a sagittal midplane of the skull; and
treating the subject by electroosmotically driving cerebrospinal fluid (CSF) out of a ventricular system of the brain via a subarachnoid space of the brain to the superior sagittal sinus, by activating control circuitry to apply one or more treatment currents between (a) one or more of the midplane treatment electrodes and (b) one or more of the lateral treatment electrodes.
2. The method according to claim 1 , wherein activating the control circuitry comprises activating the control circuitry to apply the one or more treatment currents with an average amplitude of between 1 and 3 milliamps.
3. The method according to claim 1 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes outside and in electrical contact with the skull.
4. The method according to claim 3 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes between 4 and 12 cm of the sagittal midplane of the skull.
5. The method according to claim 3 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes outside the head.
6. The method according to claim 5 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes on an external surface of the head.
7. The method according to claim 3 , wherein disposing the lateral treatment electrodes comprises implanting the lateral treatment electrodes under skin of the head.
8. The method according to claim 1 , wherein disposing the midplane treatment electrodes comprises disposing the midplane treatment electrodes outside the head.
9. The method according to claim 8 , wherein disposing the midplane treatment electrodes comprises disposing the midplane treatment electrodes on an external surface of the head.
10. The method according to claim 1 , wherein disposing the midplane treatment electrodes comprises implanting the midplane treatment electrodes under skin of the head.
11. The method according to claim 1 , wherein disposing the lateral treatment electrodes comprises implanting the lateral treatment electrodes under an arachnoid mater of the subject.
12. The method according to claim 11 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes between 1 and 3 cm of the sagittal midplane of the skull.
13. The method according to claim 11 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes in the subarachnoid space.
14. The method according to claim 11 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes in gray or white matter of a brain of the subject.
15. The method according to claim 1 , wherein disposing the midplane treatment electrodes comprises disposing the midplane treatment electrodes within 10 mm of the sagittal midplane of the skull.
16. The method according to claim 1 , wherein disposing the midplane treatment electrodes comprises disposing at least five midplane treatment electrodes over the superior sagittal sinus.
17. The method according to claim 1 , wherein activating the control circuitry comprises activating the control circuitry to configure the midplane treatment electrodes as cathodes, and the lateral treatment electrodes as anodes.
18. The method according to claim 1 ,
wherein the lateral treatment electrodes comprise left lateral treatment electrodes and right lateral treatment electrodes, and
wherein disposing the lateral treatment electrodes comprises disposing the left lateral treatment electrodes left of the sagittal midplane of the skull, and disposing the right lateral treatment electrodes right of the sagittal midplane of the skull.
19. The method according to claim 18 , wherein activating the control circuitry comprises activating the control circuitry to configure the midplane treatment electrodes as cathodes, and the left and the right lateral treatment electrodes as left and right anodes, respectively.
20. The method according to claim 18 , wherein activating the control circuitry to apply the one or more treatment currents between (a) one or more of the midplane treatment electrodes and (b) one or more of the lateral treatment electrodes comprises activating the control circuitry to apply:
a first treatment current between a first one of the midplane treatment electrodes and a first one of the left lateral treatment electrodes,
a second treatment current between the first one of the midplane treatment electrodes and a first one of the right lateral treatment electrodes,
a third treatment current between a second one of the midplane treatment electrodes and a second one of the left lateral treatment electrodes, and
a fourth treatment current between the second one of the midplane treatment electrodes and a second one of the right lateral treatment electrodes.
21. The method according to claim 1 , wherein electroosmotically driving the fluid comprises:
detecting, by the control circuitry, a voltage difference between the subarachnoid space and the superior sagittal sinus; and
setting, by the control circuitry, a level of the one or more treatment currents responsively to the detected voltage difference.
22. The method according to claim 21 , wherein detecting the voltage difference comprises detecting, by the control circuitry, the voltage difference between at least one of the midplane treatment electrodes and at least one of the lateral treatment electrodes.
23. The method according to claim 1 , wherein activating the control circuitry comprises activating the control circuitry to apply the one or more treatment currents as direct currents.
24. The method according to claim 23 , wherein activating the control circuitry comprises activating the control circuitry to apply the one or more direct currents as a plurality of pulses.