Reinforced electrode leads and methods for manufacturing the same
An exemplary electrode lead includes a flexible body formed of a flexible insulating material and that comprises a fantail region that connects to a cochlear implant configured to be implanted within a recipient and that extends to a ground electrode located toward a proximal end of the electrode lead, an electrode contact disposed on a side of the flexible body, a coiled electrode wire provided within the flexible body so as to extend along a length of the flexible body and electrically connect the electrode contact to a signal source, and a coiled reinforcing element provided within the flexible body so as to extend together with the coiled electrode wire along the length of the flexible body. The coiled reinforcing element may only be provided within a proximal portion of the electrode lead. Corresponding methods of manufacturing an electrode lead are also described.
1. An electrode lead adapted for insertion into a human body, comprising:
a flexible body formed of a flexible insulating material and that comprises a fantail region that connects to a cochlear implant configured to be implanted within a recipient and that extends to a ground electrode located toward a proximal end of the electrode lead;
an electrode contact disposed on a side of the flexible body;
a coiled electrode wire provided within the flexible body so as to extend along a length of the flexible body and electrically connect the electrode contact to a signal source; and
a coiled reinforcing element provided within the flexible body so as to extend together with the coiled electrode wire along the length of the flexible body,
wherein:
the electrode contact is provided within a distal portion of the electrode lead; and
the coiled reinforcing element:
is only provided within a proximal portion of the electrode lead that does not include the distal portion; and
is only provided in the fantail region of the flexible body that is in the proximal portion of the electrode lead.
2. The electrode lead of claim 1 , wherein:
a winding direction of the coiled electrode wire is opposite a winding direction of the coiled reinforcing element; and
a winding pitch of the coiled electrode wire is smaller than a winding pitch of the coiled reinforcing element.
3. The electrode lead of claim 2 , wherein:
the coiled electrode wire includes a plurality of helically formed windings extending along the length of the flexible body;
the winding pitch of the coiled electrode wire corresponds to a distance between successive windings included in the plurality of helically formed windings;
the coiled reinforcing element includes a plurality of additional helically formed windings extending along the length of the flexible body; and
the winding pitch of the coiled reinforcing element corresponds to a distance between successive windings included in the plurality of additional helically formed windings.
4. The electrode lead of claim 2 , wherein:
the coiled electrode wire includes a plurality of coiled electrode wires;
each coiled electrode wire included in the plurality of coiled electrode wires is bundled together so as to form a plurality of helically formed groups of windings extending along the length of the flexible body; and
the winding pitch of the coiled electrode wire corresponds to a distance between successive groups of windings included in the plurality of helically formed groups of windings.
5. The electrode lead of claim 2 , wherein:
the coiled reinforcing element includes a plurality of coiled reinforcing elements;
each coiled reinforcing element included in the plurality of coiled reinforcing elements is bundled together so as to form a plurality of helically formed groups of windings extending along the length of the flexible body; and
the winding pitch of the coiled reinforcing element corresponds to a distance between successive groups of windings included in the plurality of helically formed groups of windings.
6. The electrode lead of claim 2 , wherein:
the coiled reinforcing element includes a plurality of coiled reinforcing elements;
each coiled reinforcing element included in the plurality of coiled reinforcing elements includes a plurality of helically formed windings extending along the length of the flexible body;
successive helically formed windings included in the plurality of helically formed windings are spaced apart from each other by a same distance along the length of the flexible body; and
the winding pitch of the coiled reinforcing element corresponds to a distance between helically formed windings included in the plurality of helically formed windings of a particular coiled reinforcing element included in the plurality of coiled reinforcing elements.
7. The electrode lead of claim 2 , wherein:
the coiled reinforcing element comprises a single ribbon that includes a plurality of helically formed windings extending along the length of the flexible body; and
the winding pitch of the coiled reinforcing element corresponds to a distance between successive windings included in the plurality of helically formed windings of the single ribbon.
8. The electrode lead of claim 1 , wherein:
the coiled reinforcing element is provided at a first distance in a radial direction from a longitudinally-extending center axis of the electrode lead;
the coiled electrode wire is provided at a second distance in the radial direction from the longitudinally-extending center axis of the electrode lead; and
the first distance is greater than the second distance.
9. The electrode lead of claim 1 , wherein:
the coiled reinforcing element is provided at a first distance in a radial direction from a longitudinally-extending center axis of the electrode lead;
the coiled electrode wire is provided at a second distance in the radial direction from the longitudinally-extending center axis of the electrode lead; and
the first distance is smaller than the second distance.
10. The electrode lead of claim 1 , further comprising an additional coiled reinforcing element that has a winding direction opposite to a winding direction of the coiled reinforcing element.
11. The electrode lead of claim 1 , wherein the coiled reinforcing element is embedded within the flexible body.
12. The electrode lead of claim 1 , wherein the coiled reinforcing element is wound around the coiled electrode wire.
13. The electrode lead of claim 1 , wherein:
the flexible body includes a lumen that extends along the length of the flexible body; and
the coiled electrode wire and the coiled reinforcing element are provided within the lumen of the flexible body.
14. The electrode lead of claim 1 , wherein the coiled reinforcing element is a polymer strand.
15. An electrode lead adapted for insertion into a human cochlea, comprising:
a flexible body formed of a flexible insulating material and that comprises a fantail region that connects to a cochlear implant configured to be implanted within a recipient and that extends to a ground electrode located toward a proximal end of the electrode lead;
a plurality of electrode contacts disposed on a side of the flexible body;
a plurality of coiled electrode wires provided within the flexible body and that electrically connect the plurality of electrode contacts to a signal source, each coiled electrode wire included in the plurality of coiled electrode wires being bundled together so as to form a plurality of helically formed groups of windings extending along a length of the flexible body; and
a coiled reinforcing element provided within the flexible body and including a plurality of helically formed windings extending along the length of the flexible body together with the plurality of helically formed groups of windings of the plurality of coiled electrode wires,
wherein:
the plurality of electrode contacts is provided within a distal portion of the electrode lead; and
the coiled reinforcing element:
is only provided within a proximal portion of the electrode lead that does not include the distal portion; and
is only provided in the fantail region of the flexible body that is in the proximal portion of the electrode lead.
16. The electrode lead of claim 15 , wherein:
a winding pitch of the plurality of coiled electrode wires corresponds to a distance between successive groups of windings included in the plurality of helically formed groups of windings; and
a winding pitch of the coiled reinforcing element corresponds to a distance between successive windings included in the plurality of helically formed windings of the coiled reinforcing element.
17. A method of manufacturing an electrode lead adapted for insertion into a human body, the method comprising:
winding an electrode wire in a first winding direction to form a coiled electrode wire;
attaching the electrode wire to an electrode contact;
winding a reinforcing element in a second winding direction to form a coiled reinforcing element;
placing the coiled electrode wire, the electrode contact, and the coiled reinforcing element in an electrode lead mold such that the coiled reinforcing element extends longitudinally together with the coiled electrode wire; and
providing, after placing the coiled electrode wire, the electrode contact, and the coiled reinforcing element in an electrode lead mold, the electrode lead mold with a flexible insulating material such that the coiled electrode wire, the electrode contact, and the reinforcing element are embedded within the flexible insulating material,
wherein:
the electrode lead includes a fantail region that connects to a cochlear implant configured to be implanted within a recipient and that extends to a ground electrode located toward a proximal end of the electrode lead; and
the electrode contact is provided within a distal portion of the electrode lead; and
the coiled reinforcing element:
is only provided within a proximal portion of the electrode lead that does not include the distal portion; and
is only provided in the fantail region that is in the proximal portion of the electrode lead.
18. The method of claim 17 , wherein the winding of the reinforcing element in the second winding direction includes winding the reinforcing element around the coiled electrode wire.
19. The method of claim 17 , wherein:
the flexible insulating material is silicone; and
the providing of the electrode lead mold with the flexible insulating material includes injecting the silicone into the electrode lead mold such that a flexible body is formed when the silicone solidifies.