Implantable lead connector assembly for implantable devices and methods of using it

Claims

I claim:

1. An implantable lead connector assembly for separably, electrically connecting at least one electrode lead having at least one proximal contact to an implantable device, the lead connector assembly comprising: a closable connector housing having an open position adapted for accepting said at least one electrode lead and a closed position, the closable connector housing comprising seals adapted to isolate each of the at least one proximal contact in said closed position; a fastener adapted to maintain the connector housing in the closed position; at least one resilient electrical conductive member within said connector housing in electrical contact with a terminal adapted to connect said resilient electrical conductive member to said implantable device, said at least one resilient electrical conductive member further adapted to contact one of said at least one proximal contact of said at least one electrode lead, whereby changing said closable connector housing from said open position to said closed position compresses each said at least one resilient electrical conductive member contacting a proximal contact and isolates each said at least one proximal contact; and at least one interposer for accepting the at least one electrode lead, the at least one interposer having a sufficient number of openings exposing the at least one proximal contact of said at least one electrode lead to said at least one resilient electrical conductive member.

2. The assembly of claim 1 wherein said fastener is further adapted to change said closable connector housing from said open position to said closed position.

3. The assembly of claim 1 wherein the connector housing comprises: a clamp housing having an interior and an exterior, said interior of said clamp housing substantially conforming to an upper portion of at least one of said interposers; and a connector carriage having an interior and an exterior, said interior of said connector carriage substantially conforming to a lower portion of at least one of said interposers.

4. The assembly of claim 1 wherein said at least one interposer has conductive regions adapted substantially positionally to match the at least one proximal contact of said at least one electrode lead, wherein said at least one resilient electrical conductive member comprises said conductive regions, and said conductive regions are substantially surrounded by nonconductive regions.

5. The assembly of claim 4 further comprising a plurality of terminals, each of said plurality of terminals adapted to connect to one of said resilient electrical conductive members.

6. The assembly of claim 5 wherein each of said plurality of terminals comprises a feedthrough pin.

7. The assembly of claim 5 further comprising an insulative baseplate and wherein each of said plurality of terminals passes through said baseplate.

8. The assembly of claim 5 further comprising a filtering capacitor capacitively coupled to each of said plurality of terminals.

9. The assembly of claim 1 further comprising a plurality of said resilient electrical conductive members.

10. The assembly of claim 9 wherein said resilient electrical conductive members comprise spring contacts.

11. The assembly of claim 9 wherein said resilient electrical conductive members comprise fuzz buttons.

12. The assembly of claim 9 further comprising a plurality of terminals, each of said plurality of terminals adapted to connect to one of said resilient electrical conductive members.

13. The assembly of claim 12 wherein each of said plurality of terminals comprises a feedthrough pin.

14. The assembly of claim 12 further comprising an insulative baseplate and wherein each of said plurality of terminals passes through said baseplate.

15. The assembly of claim 12 further comprising a filtering capacitor capacitively coupled to each of said plurality of terminals.

16. An implantable lead connector assembly for separably, electrically connecting one or more implantable electrodes having at least one proximal contact to an implantable device, the lead connector assembly comprising: an interposer for accepting one or more electrode leads, where said interposer comprises an insulator and has openings for exposing the proximal contacts of said electrode lead and further comprising at least portions of seals adapted electrically to isolate said proximal contacts; a connector housing for enclosing said interposer, said connector housing having an interior and an exterior; a plurality of electrical conductive members passing from the interior to the exterior of said connector housing, said electrical conductive members each having a first end and a second end, such that said first ends of said electrical conductive members pass through said openings on said interposer for contacting the proximal contacts of said electrode lead and said second ends of said electrical conductive members projecting from said exterior of said connector housing; and a fastener adapted to compress said electrical conductive members against the proximal contacts of said electrode lead held in said interposer, forming an electrical contact.

17. The assembly of claim 16 where the connector housing is adapted to be opened and closed and wherein the fastener is further adapted to adapted to maintain said connector housing closed.

18. The assembly of claim 17 wherein said fastener is further adapted to change said connector housing from opened to closed.

19. The assembly of claim 16 wherein the connector housing comprises: a clamp housing having an interior and an exterior, said interior of said clamp housing substantially conforming to an upper portion of the interposer; and a connector carriage having an interior and an exterior, said interior of said connector carriage substantially conforming to a lower portion of the interposer.

20. The assembly of claim 16 where said plurality of electrical conductive members are resilient.

21. The assembly of claim 20 wherein said plurality of resilient electrical conductive members comprise spring contacts.

22. The assembly of claim 20 wherein said plurality of resilient electrical conductive members comprise fuzz buttons.

23. The assembly of claim 16 wherein the interior of said connector housing further comprises at least a portion of a seal that cooperatively engages with the at least portions of seals on said at least one interposer to isolate each said at least one proximal contact.

24. An implantable lead connector assembly for electrically connecting at least one implantable electrode lead each electrode lead having at least one proximal contact, to an implantable device, the lead connector assembly comprising: at least one interposer comprising an insulator, for holding said electrode lead, said interposer having an upper portion and a lower portion, and having openings on said lower portion for exposing said proximal contacts of said electrode lead; a clamp housing having an interior and an exterior, said interior of said clamp housing substantially conforming to said upper portion of at least one of said interposers; a plurality of compressible electrical connection members having a first and a second end, where said electrical connection members fit into said openings on said interposer such that said first ends of said electrical connection members will form electrical contacts with an electrode lead; a connector carriage having an interior and an exterior, said interior of said connector carriage substantially conforming to said lower portion of at least one of said interposers; a baseplate attached to said connector carnage; a plurality of electrically conductive feedthrough pins each having a first end and a second end such that said second ends of said feedthrough pins will form electrical connection to an implantable device on said exterior of said connector carriage, and said first ends of said feedthrough pins will form electrical contacts with said second ends of said electrical connection members; and a fastener for holding said clamp housing to said connector carriage, adapted to hold said interposer between said clamp housing and said connector carnage to make contact between said feedthrough pins and said electrode lead via said electrical connection members.

25. The assembly of claim 24 further comprising a seal interior of said clamp housing that isolates each electrode lead within said interposer between said interior of said clamp housing and said interior of said connector carriage upon engaging said fastener.

26. The assembly of claim 25 where said upper portion of said interposer further comprises clips for holding the electrode lead.

27. The assembly of claim 24 where said interior of said connector carriage further comprises at least two alignment posts adapted to fit into said alignment holes interior of said clamp housing.

28. The assembly of claim 24 where said electrical connection members are fuzz button connectors.

29. The assembly of claim 28 where said fuzz button connectors are held in said interposer by a conductive retaining layer attached to said interposer.

30. The assembly of claim 24 where said fastener is a screw passing through said clamp housing that couples with a threaded hole on said connector carriage.

31. The assembly of claim 24 where said fastener is a screw removably retained in said clamp housing.

32. The assembly of claim 24 where said baseplate further comprises at least one ceramic layer.

33. The assembly of claim 24 where said baseplate further comprises at least one filter capacitor capacitively coupled to at least one feedthrough pin.

34. The assembly of claim 24 wherein said connector carriage holds exactly two of said interposers.

35. The assembly of claim 24 wherein said electrical connection members comprise spring contacts and each of said spring contacts is attached to said first ends of each of said feedthrough pins.

36. The assembly of claim 35 wherein said spring contacts are an alloy of 80-20 Platinum-Iridium.

37. The assembly of claim 24 wherein said upper portion of said interposer is separable from said lower portion of said interposer.

38. A method of connecting an implantable electrode lead to an implantable device comprising: providing an implantable electrode lead; providing an implantable device; providing an implantable lead connector assembly, the assembly comprising an interposer having openings, a connector housing and a fastener, where the connector housing includes electrical connection members fitting within said interposer openings and that are electrically continuous with pins projecting from an external face of the connector housing.

39. The method of claim 38 further comprising the steps of: sealing the implantable electrode lead into the interposer by activating the fastener.

FIELD OF THE INVENTION

This invention relates to an apparatus for connecting implantable electrode leads to an implantable device, and more particularly to an implantable connection device that may be used to connect cortical, deep brain (i.e., "depth"), or other electrode leads from a patient's brain to a device that is typically also implanted as an integrated portion of a system for detecting, monitoring, or stimulating electrical activity in a patient's brain. The invention includes methods for use of the device.

BACKGROUND

Systems for electrically monitoring and stimulating the brain are increasingly important in the medical diagnosis and treatment of various brain disorders, such as epilepsy, Parkinson's disease, sleep disorders, migraine, and psychiatric ailments. Therapeutic neurostimulatory devices may include one or more leads having at least one electrodes operatively situated in the brain or other neural tissue and linked to a signal processor for detecting neurological activity and to a pulse generator for providing electrical stimuli.

Many functional and aesthetic advantages may be achieved by implanting the signal processing and pulse generator portions of neurostimulator devices in the cranium. From a purely esthetic point of view, the electrode leads need not run along the scalp and down the neck. Connecting implanted electrodes to devices located in other regions of the body mandates that the electrode leads be lengthy. For instance, the Medtronic Activa.RTM. device uses leads that are tunneled along the neck and down the chest to the pectoral region where the neurostimulator resides. Such a pathway subjects the leads to increased risk of fatigue and to a higher susceptibility to noise from a variety of external electromagnetic sources. This inventive device assists in solving these very real problems.

One example of a system implantable beneath the scalp is found in U.S. Pat. No. 6,016,449 entitled "System for Treatment of Neurological Disorders" to Fischell, et al. (hereinafter "Fischell"). Fischell et al discloses a responsive detection and stimulation system for the early recognition and prompt treatment of a neurological event arising from neurological disorders such as epilepsy, migraine headaches, and Parkinson's disease. In Fischell et al's device, the entire implantable portion of the system for treating neurological disorders lies beneath the patient's scalp. By placing the entire system within the cranium, as opposed to extending wires into or through the neck to a control module in the chest, the probability of wire breakage due to repeated wire bending is drastically reduced. Other examples of devices implanted in the cranium for applying electrical stimulation therapies to electrodes situated at appropriate locations include cochlear implants.

Typical cranial electrode arrays are either brain surface electrode arrays or depth arrays. Brain surface electrodes often include an array of disk-shaped electrodes that are placed on the surface of the patients brain. The electrode arrays may be arranged in different formations and the number of electrodes per array may also vary. Depth electrodes are also usually small diameter leads having multiple distal electrodes on the same (or possibly branching) shaft. The major difference between the physical appearance of the two types is that the depth arrays are made up of a number of ring electrodes located distally on the lead. In either case, the proximal ends of the electrode leads may be arranged so that the those proximal contacts or termini are spaced along the shaft of the lead, electrically separated, one from the other. The physical separation of those proximal contacts is often via use of a non-conductive tubular portion, typically of the same material as the remainder of the electrode lead assembly's shaft. In turn, the lead connector assembly links the electrodes of the lead to the implantable device. It is essential that the lead connector device reliably connect each of the electrodes without functional failure.

Accordingly, it would be desirable to have an electrode lead connection device which is implantable into a patient's cranium. Such a device desirably ensures a reliable electrical connection between the electrodes and an implantable neurostimulatory or monitoring device. Furthermore, the lead connector should be easy for the surgeon to use and allow replacement of the neurostimulatory or monitoring device without having to replace the electrode leads.

SUMMARY OF THE INVENTION

This invention relates to an apparatus--an implantable lead connector assembly--for connecting implantable electrode leads to an implantable device. The invention accepts at least one electrode lead and seats it within an interposer that in turn is secured inside a connector housing that can be electrically connected to an implantable device. The entire lead connector assembly is implantable. The interposer is adapted to seat an electrode lead and allow access to all of the proximal contacts on the lead via electrical conductive members in the inventive implantable lead connector assembly. Desirably, the step of securing the connector housing in the closed position compresses electrically conductive members situated within the connector housing into contact with the electrode lead, and simultaneously compresses the seal to electrically isolate not common electrical members, resulting in a reliable electrical connection between the electrode lead and the electrical conductive members. The electrically conductive members may project through the connector housing where they can link to an implantable device, such as a signal processor or stimulator, or, alternatively, the electrically conductive members may electrically connect to passthrough pins or wires that link to the implantable device. The inventive lead connector may accommodate several lead electrodes.

The electrically conductive members, when compressible, may take differing forms.

One preferred variation of the invention includes using at least one spring contact as the compressible electrical conductive member that contacts the lead electrode and an interposer capable of accommodating the spring contacts as well as the lead electrode.

Another variation of the invention uses a fuzz button connector as the compressible electrical conductive member that contacts the lead electrode when the assembly is secured, and also an interposer capable of accommodating the fuzz button connectors as well as the electrode lead.

Another variation of the invention includes a split interposer that cooperates with other components of the inventive lead connector assembly, e.g., the connector housing that also may be split and associated connector housing seals, so that the step of securing the connector housing also seals the lead electrode within the then-joined interposer.

Still another variation of the interposer obviates the need for fuzz buttons and spring clips by use of a formed or molded interposer having regions of conductive materials generally matching the spacing of the proximal contacts on the electrode lead.

The invention further includes a method of connecting an implantable electrode lead to an implantable device. The method involves inserting an implantable electrode into a patients brain and providing an implantable lead connector assembly and an implantable device. The implantable lead connector assembly includes an interposer, a connector housing, and a fastener such that the connector housing has compressible electrical connection members that can form electrical contacts with the electrode lead when the device is secured.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the electrode lead connector of the present invention shown disassembled into a clamp housing and a connector carriage with a split interposer seated therein and having a typical electrode lead.

FIG. 2A is a perspective view of one variation of an interposer for holding fuzz button contacts.

FIG. 2B is a persp