Medical implants and electronics and antenna assemblies for use with same
An electronics and antenna assembly is disclosed for use with a medical implant.
1 . An electronics and antenna assembly for use in a medical implant, the electronics and antenna assembly comprising:
a metal electronics case having a length, a width and a thickness that is less than the length and the width, and including first and second end walls and a side wall that defines the thickness, an internal volume, and an external recess with a closed bottom end defined entirely by the first end wall and a perimeter defined at least partially by the side wall;
electronic components within the internal volume;
an antenna/shield cover within the external recess and formed from a first material;
an antenna coil within the external recess and between the end wall and the antenna/shield cover; and
an electromagnetic shield within the external recess between the antenna coil and the end wall, formed from a second material that is different than the first material and that has a magnetic permeability of about 25 to about 250, and defining an annular shield recess in which the antenna coil is located.
2 . An electronics and antenna assembly as claimed in claim 1 , wherein
the metal electronics case comprises a titanium electronics case.
3 . An electronics and antenna assembly as claimed in claim 1 , wherein
the electromagnetic shield is about 0.1 mm to about 1.5 mm thick.
4 . An electronics and antenna assembly as claimed in claim 1 , wherein
the electronic components within the internal volume include a cochlear implant stimulation processor.
5 . A cochlear implant, comprising:
the electronics and antenna assembly claimed in claim 4 ; and
a cochlear lead with an electrode array operably connected to the cochlear implant stimulation processor.
6 . An electronics and antenna assembly as claimed in claim 1 , wherein
the antenna/shield cover is formed from an electrically non-conductive high-strength material.
7 . An electronics and antenna assembly as claimed in claim 1 , wherein
the electromagnetic shield is formed from a soft ferrite.
8 . An electronics and antenna assembly for use in a medical implant, the electronics and antenna assembly comprising:
a metal electronics case having an internal volume, an end wall and an external recess adjacent to the end wall;
electronic components within the internal volume;
an antenna within the external recess; and
an electromagnetic shield within the external recess between the antenna and the end wall;
wherein
the antenna includes an annular non-conductive substrate that defines an opening and a coil on the substrate;
the metal electronics case includes a magnet case;
at least one rotatable magnet is located within the magnet case; and
a portion of the magnet case extends through the opening in the non-conductive substrate.
9 . An electronics and antenna assembly as claimed in claim 8 , wherein
the at least one rotatable magnet is permanently secured within the metal electronics case.
10 . An electronics and antenna assembly as claimed in claim 8 , wherein
the magnet case defines a central axis; and
the at least one rotatable magnet comprises a plurality of elongate diametrically magnetized magnets that are located in a magnet frame, the magnet frame is rotatable about the central axis of the case, and the elongate diametrically magnetized magnets define a longitudinal axis and a N-S direction and are rotatable about the longitudinal axis relative to the magnet frame.
11 . An electronics and antenna assembly as claimed in claim 8 , wherein
an elastomer covers a portion of the metal electronics case, antenna and shield;
the metal electronics case, antenna, shield and elastomer together occupy a first volume;
the magnet case includes an interior that defines a second volume; and
the ratio of the first volume to the second volume is less than or equal to 9.7.
12 . An electronics and antenna assembly as claimed in claim 11 , wherein
the ratio of the first volume to the second volume is less than or equal to 9.7 and is greater than or equal to 6.1.
13 . An electronics and antenna assembly as claimed in claim 8 , wherein
an antenna/shield cover within the external recess;
wherein the antenna and the electromagnetic shield are between the end wall and the antenna/shield cover.
14 . An electronics and antenna assembly as claimed in claim 8 , wherein
the electromagnetic shield includes a recess and the antenna is located within the electromagnetic shield recess.
15 . An electronics and antenna assembly as claimed in claim 8 , wherein
the electromagnetic shield is formed from a material with a high magnetic permeability.
16 . An electronics and antenna assembly as claimed in claim 8 , wherein
the electronic components within the internal volume include a cochlear implant stimulation processor.
17 . A cochlear implant, comprising:
the electronics and antenna assembly claimed in claim 16 ; and
a cochlear lead with an electrode array operably connected to the cochlear implant stimulation processor.