1. Apparatus comprising:
an assembly, said assembly comprising:
a housing configured to be applied to a nerve of a subject, the housing shaped to define a chamber, an interior of said chamber being in fluid communication with the nerve when the housing is applied to the nerve, wherein at least one wall of the chamber comprises a membrane that separates the interior of the chamber from a region outside the chamber;
at least a first electrode, which is positioned within the chamber; and
at least a second electrode, which is positioned in the region outside the chamber, in a vicinity of the membrane; and
a control unit, which is configured to:
drive a current between the first and second electrodes such that the first electrode has a positive charge, and the second electrode has a negative charge, and
the control unit further configured to: configure the current to increase a pH in the interior of the chamber in order to inhibit action potentials traveling in the nerve past the chamber.
2. The apparatus according to claim 1,
wherein the current includes a first current,
wherein the assembly comprises at least one cathode, and
wherein the control unit is further configured to:
drive the cathode to apply a second current to the nerve that generates action potentials traveling in first and second directions in the nerve, and
configure the first current to increase the pH in order to block propagation past the chamber of at least a portion of the action potentials traveling in the second direction, and
drive the first current between the first and second electrodes, wherein the driving of the first current is not coordinated with the driving of the cathode.
3. The apparatus according to claim 1, wherein the control unit is configured to drive the current substantially continuously for a period of time that is greater than one minute.
4. The apparatus according to claim 3, wherein the control unit is configured to drive the current substantially continuously for a period of time that is greater than one hour.
5. The apparatus according to claim 1, wherein the control unit is configured to generate an increased level of sodium and hydroxide ions inside the chamber by driving the current.
6. The apparatus according to claim 5, wherein the control unit is configured to inhibit action potentials traveling in the nerve past the chamber by facilitating diffusion of the sodium and the hydroxide ions into the nerve.
7. The apparatus according to claim 5, wherein the control unit is configured to generate an increased level of hydrogen and chloride ions in a vicinity of the second electrode by driving the current.
8. The apparatus according to claim 7, wherein the membrane is configured to separate (a) the sodium and the hydroxide ions, from (b) the hydrogen and the chloride ions.
9. A method comprising:
placing a housing in a vicinity of a nerve of a subject such that an interior of a chamber defined by the housing is in fluid communication with the nerve, wherein at least one wall of the chamber includes a membrane that separates the interior of the chamber from a region outside the chamber;
driving a current between a first site within the chamber and a second site in the region outside the chamber, the second site being in a vicinity of the membrane; and
configuring the current to increase a pH in the interior of the chamber sufficiently to inhibit action potentials traveling in the nerve past the chamber.
10. The method according to claim 9,
wherein driving the current comprises driving a first current between the first and second sites,
further comprising applying a second current to the nerve that generates action potentials traveling in first and second directions in the nerve,
wherein configuring the current comprises configuring the first current to increase the pH sufficiently to block propagation past the chamber of at least a portion of the generated action potentials traveling in the second direction, and
wherein driving the first current comprises driving the first current not in coordination with the driving of the second current.
11. The method according to claim 9, wherein driving the current comprises driving the current substantially continuously for a period of time that is greater than one minute.
12. The method according to claim 11, wherein driving the current comprises driving the current substantially continuously for a period of time that is greater than one hour.
13. The method according to claim 9, wherein configuring the current comprises generating an increased level of sodium and hydroxide ions inside the chamber.
14. The method according to claim 13, wherein configuring the current comprises inhibiting action potentials traveling in the nerve past the chamber by facilitating diffusion of the sodium and the hydroxide ions into the nerve.
15. The method according to claim 13, wherein configuring the current comprises generating an increased level of hydrogen and chloride ions in the region outside the chamber.
16. The method according to claim 15, wherein placing the housing in the vicinity of the nerve comprises separating, using the membrane, (a) the sodium and the hydroxide ions, from (b) the hydrogen and the chloride ions.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A system (10) for planning a neurosurgical operation, the system (10) comprising:
an input (11) for receiving functional data and anatomical data (25) of a brain region (31), and
a processor (12) configured to:
analyze the functional data (25) to form a network representation (27) of functional connections, the network representation (27) comprising network nodes (32) and network connections (41) interconnecting the network nodes (32),
map the network representation (27) of the functional connections and the anatomical data to a common coordinate system,
determine an expected function loss associated with a simulated removal of one of the network nodes (32) or network connections (41) from the network representation, and to
identify critical network connections andor critical network nodes based on the expected function loss.
2. A system (10) for planning a neurosurgical operation as claimed in claim 1, wherein the processor (12) is further configured to perform a topological network analysis of the network representation (27) for determining the expected function loss.
3. A system (10) for planning a neurosurgical operation as claimed in claim 2, wherein the processor (12) is further configured to calculate clustering coefficients of the network nodes (32) andor path lengths of the network connections (41) for performing the topological network analysis of the network representation.
4. A system (10) for planning a neurosurgical operation as claimed in claim 1, wherein the functional data comprises multiple data channels (25) and wherein the processor (12) is further configured to calculate a pair wise correlation of the functional data channels (25) for analyzing the functional data.
5. A system (10) for planning a neurosurgical operation as claimed in claim 1, the system (10) further comprising planning tools for planning a surgical trajectory avoiding the identified critical network connections andor critical network nodes.
6. A system (10) for planning a neurosurgical operation as claimed in claim 1, further comprising an output (14) for providing a visual representation (29) of the network representation (27) of the functional connections.
7. A system (10) for planning a neurosurgical operation as claimed in claim 6, wherein the critical network connections andor the critical network nodes are highlighted in the visual presentation (29).
8. A system (10) for planning a neurosurgical operation as claimed in claim 6, wherein an appearance of the network connections (41) and of the network nodes (32) in the visual representation (29) is dependent on the expected function loss.
9. A system (10) for planning a neurosurgical operation as claimed in claim 6, wherein the visual representation (29) further represents the anatomic data.
10. A system (10) for planning a neurosurgical operation as claimed in claim 6, wherein the functional data (25) comprises fMRI, EEG, MEG andor NIRS data.
11. A system (10) for planning a neurosurgical operation as claimed in claim 6, wherein the anatomic information comprises MRI andor DTI data.
12. A method (20) for planning a neurosurgical operation, the method comprising:
receiving functional data (25) and anatomical data of a brain region (31),
analyzing (26) the functional data (25) to form (22) a network representation (27) of functional connections, the network representation (27) comprising network nodes (32) and network connections (41) interconnecting the network nodes (32),
mapping (24) the network representation (27) of the functional connections and the anatomical data to a common coordinate system,
determining (23) an expected function loss associated with a simulated removal of one of the network nodes (32) or network connections (41) from the network representation (27),
based on the expected function loss, identifying critical network connections andor critical network nodes.
13. A computer program product for planning a neurosurgical operation, which program is operative to cause a processor to perform the method as claimed in claim 12.