Electrical treatment of Alzheimer's disease
A method is provided that includes disposing midplane treatment electrodes over a superior sagittal sinus, outside and in electrical contact with a skull of a head of a subject identified as at risk of or suffering from Alzheimer's disease. Lateral treatment electrodes are disposed between 1 and 12 cm of a sagittal midplane of the skull. The subject is treated by electroosmotically driving fluid from a subarachnoid space 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 sore of the lateral treatment electrodes. Other embodiments are also described. Other embodiments are also described.
1. A method comprising:
disposing midplane treatment electrodes over a superior sagittal sinus, outside and in electrical contact with a skull of a head of a subject identified as at risk of or suffering from Alzheimer's disease;
disposing lateral treatment electrodes between 1 and 12 cm of a sagittal midplane of the skull; and
treating the subject by electroosmotically driving fluid from a subarachnoid space 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 treating the subject comprises facilitating clearance of amyloid beta from the subarachnoid space to the superior sagittal sinus by electroosmotically driving the fluid from the subarachnoid space to the superior sagittal sinus.
3. The method according to claim 1 , wherein treating the subject comprises facilitating clearance of metal ions from the subarachnoid space to the superior sagittal sinus by electroosmotically driving the fluid from the subarachnoid space to the superior sagittal sinus.
4. 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.
5. The method according to claim 4 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes between 4 and 12 cm of the sagittal midplane of the skull.
6. The method according to claim 4 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes outside the head.
7. The method according to claim 6 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes on an external surface of the head.
8. The method according to claim 4 , wherein disposing the lateral treatment electrodes comprises implanting the lateral treatment electrodes under skin of the head.
9. The method according to claim 1 , wherein disposing the midplane treatment electrodes comprises disposing the midplane treatment electrodes outside the head.
10. The method according to claim 9 , wherein disposing the midplane treatment electrodes comprises disposing the midplane treatment electrodes on an external surface of the head.
11. The method according to claim 1 , wherein disposing the midplane treatment electrodes comprises implanting the midplane treatment electrodes under skin of the head.
12. 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.
13. The method according to claim 12 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes between 1 and 3 cm of the sagittal midplane of the skull.
14. The method according to claim 12 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes in the subarachnoid space.
15. The method according to claim 12 , wherein disposing the lateral treatment electrodes comprises disposing the lateral treatment electrodes in gray or white matter of a brain of the subject.
16. 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.
17. 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.
18. 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.
19. 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.
20. The method according to claim 19 , 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.
21. The method according to claim 19 , 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.
22. 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.
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. A method comprising:
disposing one or more midplane treatment electrodes over a superior sagittal sinus, outside and in electrical contact with a skull of a head of a subject identified as at risk of or suffering from Alzheimer's disease;
disposing one or more lateral treatment electrodes between 1 and 12 cm of a sagittal midplane of the skull; and
treating the subject by electroosmotically driving fluid from a subarachnoid space 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.
25. The method according to claim 24 ,
wherein the one or more lateral treatment electrodes comprise one or more left lateral treatment electrodes and one or more right lateral treatment electrodes, and
wherein disposing the one or more lateral treatment electrodes comprises disposing the one or more left lateral treatment electrodes left of the sagittal midplane of the skull, and disposing the one or more right lateral treatment electrodes right of the sagittal midplane of the skull.
26. The method according to claim 25 , wherein activating the control circuitry comprises activating the control circuitry to configure the one or more midplane treatment electrodes as one or more cathodes, the one or more left lateral treatment electrodes as one or more left anodes, and the one or more right lateral treatment electrodes as one or more right anodes.
27. Apparatus for treating a subject identified as at risk of or suffering from Alzheimer's disease, the apparatus comprising:
exactly three leads, consisting of a midplane lead, a left lateral lead, and a right lateral lead;
at least five midplane electrodes, which are disposed along the midplane lead at an average distance of at least 1 cm between longitudinally-adjacent pairs of the midplane electrodes, measured between longitudinal midpoints of the midplane electrodes;
at least five left lateral electrodes, which are disposed along the left lateral lead at an average distance of at least 1 cm between longitudinally-adjacent pairs of the left lateral electrodes, measured between longitudinal midpoints of the left lateral electrodes;
at least five right lateral electrodes, which are disposed along the right lateral lead at an average distance of at least 1 cm between longitudinally-adjacent pairs of the right lateral electrodes, measured between longitudinal midpoints of the right lateral electrodes; and
a housing, which comprises control circuitry, to which the midplane, the left lateral, and the right lateral electrodes are electrically coupled via the midplane lead, the left lateral lead, and the right lateral lead, respectively, the control circuitry configured to:
configure the midplane treatment electrodes as cathodes, and the left and the right lateral treatment electrodes as left and right anodes, respectively,
apply respective treatment currents between (a) (i) one or more of the midplane treatment electrodes and (ii) one or more of the left lateral treatment electrodes, and (b) (i) one or more of the midplane treatment electrodes and (ii) one or more of the right lateral treatment electrodes, and
configure the treatment currents to treat the subject by electroosmotically driving fluid from a subarachnoid space to a superior sagittal sinus of the subject.