Cochlear implants having MRI-compatible magnet apparatus and associated methods
A cochlear implant is disclosed including a cochlear lead, an antenna, a stimulation processor, a magnet apparatus, associated with the antenna, including a case, a divider, and a plurality of magnetic material particles that are movable relative to one another within sub-volumes defined by the divider.
1. A cochlear implant, comprising:
a cochlear lead including a plurality of electrodes;
an antenna;
a stimulation processor operably connected to the antenna and to the cochlear lead; and
a magnet apparatus, associated with the antenna, including a case with an internal volume, a divider that separates the internal volume into a plurality of sub-volumes, and respective pluralities of magnetic material particles packed within the sub-volumes in such a manner that adjacent magnetic material particles are in contact with one another and are also movable relative to one another.
2. A cochlear implant as claimed in claim 1 , wherein
the magnetic material particles are each are free to move from one X-Y-Z coordinate to another and to rotate in any direction.
3. A cochlear implant as claimed in claim 1 , wherein
the magnetic material particles are at least substantially polyhedral in shape; and/or
the magnetic material particles define mesh sizes that range from 50 μm to 500 μm, or from 100 μm to 300 μm, or from 300 μm to 500 μm; and/or
the magnetic material particles are formed from a material selected from the group consisting of neodymium-iron-boron, magnetic material, isotropic neodymium, anisotropic neodymium, samarium-cobalt.
4. A cochlear implant as claimed in claim 1 , wherein
the case comprises a disk-shaped case or a square case.
5. A cochlear implant as claimed in claim 1 , wherein
the case is formed from a material selected from the group consisting of paramagnetic metal and plastic.
6. A cochlear implant as claimed in claim 1 , further comprising:
a magnetic field focusing shim located within the case.
7. A cochlear implant as claimed in claim 1 , wherein
the antenna, the stimulation processor and the magnet apparatus are located within a flexible housing.
8. A cochlear implant as claimed in claim 1 , wherein
at least some of the plurality of sub-volumes are three-dimensionally uniform.
9. A cochlear implant as claimed in claim 8 , wherein
at least some of the plurality of sub-volumes are at least substantially three-dimensionally uniform.
10. A cochlear implant as claimed in claim 1 , wherein
at least some of the plurality of sub-volumes are at least substantially three-dimensionally uniform.
11. A cochlear implant as claimed in claim 1 , wherein
the case includes a base and a cover, the base defines a height, the divider defines a height, and the base height is 90% to 99% of the divider height.
12. A cochlear stimulation system, comprising:
a cochlear implant as claimed in claim 1 ; and
a sound processor including
a housing,
sound processor circuitry carried within the housing, and
a communication device adapted to operably connect the sound processor circuitry to the cochlear implant.
13. A cochlear stimulation system as claimed in claim 12 , wherein
the communication device comprises a square antenna.
14. A cochlear stimulation system as claimed in claim 13 , wherein
the sound processor includes a headpiece and the square antenna part of the headpiece.
15. A cochlear stimulation system as claimed in claim 14 , wherein
the headpiece includes a square housing.