US 5,515,848 A · Implantable microelectrode

Abstract

A miniature, electrically-insulated multi-conductor electrical cable suitable for implantation in living bodies and readily connected to sensors or electrodes, and implantable microelectrodes attached to such cables. Individual electrical conductors are coated with at least one layer of, insulating material and stranded together, or optionally bound together by an additional layer of insulating material which is compatible with implantation in living bodies. The individual conductors are separated from one another in terminal portions of the cable and are held by a ribbonizing resin at a predetermined pitch to facilitate connection of each of the conductors. The terminal portions may define microelectrodes. Another microelectrode includes an electrically conductive electrode core member sharpened and coated with a thin layer of a dielectric material. An extremely small area of the core at the sharpened point is exposed by ablating the dielectric material by the use of an ultraviolet laser beam scanned over the material. Multiple conductor microelectrodes may also be supported within a hollow needle or in flat ribbon configuration, with openings in dielectric material defining active electrode sites. Multiple active electrode sites may be defined on a microelectrode accompanied by an integrated circuit after connection of the integrated circuit to a multiconductor cable.

Claims39

Dependent claims

A biologically implantable multiconductor microelectrode, comprising:

(a) a plurality of fine wires, all of said fine wires being wrapped helically around a sharp-pointed electrode support core;
(b) a quantity of a dielectric material covering a portion of each of said plurality of fine wires and electrically insulating said fine wires from each other and holding said fine wires together in a predetermined spatial relationship with each other, said quantity of dielectric material having an outer surface and defining a plurality of openings, each of said openings communicating between said outer surface and a respective one of said fine wires and exposing a predetermined area of a respective one of said fine wires therethrough.

In combination, a miniature electrical conductor cable and a biologically implantable microelectrode, comprising:

(a) a pair of opposite ends and an intermediate portion of said cable;
(b) a plurality of very small elongate flexible electrical conductors each having respective opposite ends corresponding with said opposite ends of said cable, each said conductor having a respective intermediate portion extending between said opposite ends thereof, said intermediate portions of said conductors being located closely alongside one another in a predetermined arrangement defining said intermediate portion of said cable;
(c) a first layer of a first electrical insulating material constituting a separate thin substantially continuous coating on each of said plurality of conductors;
(d) at least one of said opposite ends of said cable having a respective ribbonized portion including a respective transition portion in which said plurality of conductors diverge from one another and a terminal portion in which said plurality of conductors are arranged generally parallel with each other and are separated from one another by a predetermined pitch;
and
(e) said plurality of conductors in said transition portions and terminal portions of said ribbonized portion included in said one of said opposite ends being covered and surrounded by and supported by a quantity of a ribbonizing material and being held in predetermined relative positions with respect to each other by said ribbonizing material, a plurality of openings being defined through said ribbonizing material and said first layer in said terminal portion, and a predetermined area of each of said conductors being cleanly exposed adjacent said ribbonizing material within each said opening as a respective active electrode site, said active electrode sites together constituting a microelectrode.

3 more elements

A miniature electrical conductor cable suitable for implantation in a living body, comprising:

(a) a pair of opposite ends and an intermediate portion;
(b) a plurality of very small elongate flexible electrical conductors each having respective opposite ends corresponding with said opposite ends of said cable, each said conductor having a respective intermediate portion extending between said opposite ends thereof, said intermediate portions of said conductors being arranged together with each other in a helical circular strand defining said intermediate portion of said cable;
(c) a respective first layer of a first electrical insulating material, said first layer having a thickness and constituting a separate thin substantially continuous coating, surrounding said intermediate portion of each of said plurality of conductors;
(d) at least one of said opposite ends of said cable having a respective ribbonized portion defined by said plurality of conductors of said cables being substantially covered by and supported by a quantity of a ribbonizing material adhered thereto and having a predetermined thickness greater than that of said first layer, said conductors being held in predetermined relative positions with respect to each other by said ribbonizing material, said ribbonized portion including a respective transition portion adjacent said intermediate portion and said plurality of conductors diverging from one another in a single stratum in said transition portion, and said ribbonized portion also including a respective terminal portion adjacent said transition portion, said plurality of conductors in said terminal portion being parallel with each other and separated from one another by a predetermined pitch;
and
(e) an electrically connectable surface portion of each of said conductors being exposed adjacent said ribbonizing material of said terminal portion.

3 more elements

Dependencies are inferred from the claim text.

Implantable microelectrode

Life of this patent

Implantable microelectrode

Life of this patent

Abstract

Claims39