Cochlear implant

• US 20030171787A1
• Filed: 05/09/2003
• Published: 09/11/2003
• Est. Priority Date: 06/30/2000
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Seligman, Peter, Money, David, Zhang, Andy L., Ibrahim, Ibrahim, Nygard, Tony
• Granted Patent: US 7,346,397 B2
• Time in Patent Office: Days
• US Class Current: 607/57
• CPC Class Codes: A61N 1/36038 Cochlear stimulation

Abstract

A totally implantable cochlear implant system forming a single implantable unit (40). The unit (40) has an implantable power source (43) that provides the power requirements of the implantable unit (40). The unit (40) also has an on-board microphone (42) that detects external sounds, such as speech, and outputs acoustic signals representative of the detected sounds. The unit further includes speech processor circuitry (44) that directly receives the acoustic signals from the microphone (42) and converts the signals into stimulation signals representative of the detected sounds. An electrode array (20) suitable for insertion of the cochlea (2) of an implantee receives the stimulation signals and transmits electrical stimulations to the implantee'"'"'auditory nerve (9).

Claims

1. A totally implantable cochlear implant system having an implantable unit comprising:

(i) a hermetically sealed housing including;

(a) a power source that provides the power requirements of the implantable unit;

(b) a microphone that detects sounds and outputs acoustic signals representative of said detected sounds; and

(c) a processor means that directly receives said acoustic signals and converts the signals into stimulation signals representative of the detected sounds; and

(ii) an electrode array suitable for insertion in the cochlea of an implantee, the array once inserted being adapted to receive the stimulation signals and output electrical stimulation to the implantee'"'"'s auditory nerve.

2. The system of claim 1 wherein the housing is formed from a biocompatible material.

3. The system of claim 2 wherein the housing is formed from titanium and is hermetically sealed before implantation into an implantee.

4. The system of claim 3 wherein the housing has relatively smooth surfaces and is coated with a layer of silicone.

5. The system of claim 1 wherein the microphone is housed within the housing.

6. The system of claim 1 wherein the microphone is positioned adjacent a surface of the housing that faces outwardly following implantation of the housing.

7. The system of claim 6 wherein the microphone functions within a pressure ranging from about 1.5 atm to about 0.7 atm.

8. The system of claim 1 wherein the power source provides power for the microphone, processor means, electrode array and any other electrical or electronic componentry of the implant system.

9. The system of claim 8 wherein the system has a warning system that provides an indication to the implantee that the power source requires recharging.

10. The system of claim 9 wherein the warning system generates a unique stimulus signal that the implantee is trained to recognise as an indication that the power source needs recharging.

11. The system of claim 10 wherein the system has an interrogation means that allows the implantee to determine the charge level of the power source.

12. The system of claim 1 wherein the system includes a wire antenna receiver coil external of the housing that acts as part of a radio frequency (RF) link to allow bidirectional data transfer between the system and one or more external devices.

13. The system of claim 12 wherein the antenna receiver coil is disposed about a magnet.

14. The system of claim 13 wherein the magnet is removable from the antenna receiver coil.

15. The system of claim 12 wherein the antenna receiver coil also acts as a power receiver to allow inductive charging of the power source of the system.

16. The system of claim 1 wherein the processor means of the invention is mounted on a circuit board within the housing.

17. The system of claim 12 wherein the processor means comprises a speech processor and a stimulation processor.

18. The system of claim 17 wherein the system is usable in association with an external device that communicates with the implanted unit via the radio frequency (RF) link, the external device comprising at least an external speech processor, an external power source, and an external microphone.

19. The system of claim 18 wherein the external power source is useable as a recharger of the power source in the housing via the radio frequency (RF) link.

20. The system of claim 1 wherein the system includes an implanted deactivation means.

21. The system of claim 20 wherein operation of the deactivation means places the system in a shutdown mode whereby electrical stimulation of the cochlea is stopped.

22. The system of claim 20 wherein operation of the deactivation means results in complete shutdown of the system.

23. The system of claim 20 wherein a first operation of the deactivation means stops electrical stimulation of the cochlea and a second operation of the deactivation means results in complete shutdown of the system.

24. The system of claim 20 wherein the deactivation means comprises a mechanical switch that is implantable subcutaneously with the system.

25. The system of claim 20 wherein the deactivation means is mounted in or on the housing of the system.

26. The system of claim 20 wherein the deactivation means comprises a resonance circuit, a waveform generator circuit in the housing that outputs a relatively narrow energy waveform that excites the resonance circuit at a regular interval, and a waveform monitoring means that monitors one or more features of the generated waveform following the excitation, wherein any change in the features of the waveform resulting from a metal object being brought to a position adjacent the resonance circuit but external the skin of the implantee are detectable by the monitoring means which, on detection, outputs a signal that at least stops electrical stimulation of the cochlea.

27. The system of claim 26 wherein the waveform generator circuit which outputs the regular narrow energy waveform is electrically separate from the processor means but physically located in the same integrated circuit.

28. The system of claim 20 wherein the deactivation means monitors acoustic signals output by the implanted microphone and at least triggers shutdown of electrical stimulation of the cochlea by the electrode array on detection of a predetermined type of acoustic signal.

29. The system of claim 28 wherein the predetermined type of acoustic signal is a sound generated on tapping of the skull of the implantee.

30. The system of claim 29 wherein the predetermined type of acoustic signal is a double tap on the skull of the implantee, the double tap occurring within a predetermined relatively short period.

31. The system of claim 13 wherein the system includes an implanted deactivation means that comprises a sensing coil wrapped around the magnet of the wire antenna receiver coil, the magnet being movable relative thereto, and a current detection circuit, wherein depression of the magnet by the implantee relative to the sensing coil or vice versa induces a current in the sensing coil that is detectable by the current detection circuit which, on detection, outputs a signal that at least stops electrical stimulation of the cochlea.

32. The system of claim 20 wherein a portion of the outer surface of the housing incorporates a switch comprising a compliant membrane positioned above an electrical terminal positioned within the housing, and a current detection circuit, wherein pressure applied to the compliant membrane transcutaneously by the implantee causes current to flow through the switch that is detectable by the current detection circuit which, on detection, outputs a signal that at least stops electrical stimulation of the cochlea.

33. The system of claim 20 wherein the system includes a piezoelectric membrane implantably positioned so as to be deflectable by the implantee, and a current detection circuit, wherein on its deflection, the piezoelectric membrane generates a current that is detectable by the current detection circuit which, on detection, outputs a signal that at least stops electrical stimulation of the cochlea.

34. The system of claim 20 wherein the system includes two or more deactivation means.

35. The system of claim 1 wherein the implant system includes a telecoil.

36. A cochlear implant system having an implantable unit adapted to work, when necessary, in conjunction with an external device, wherein:

the implantable unit comprises;

(i) a hermetically sealed housing including;

(a) a power source that provides the power requirements of the implantable unit;

(b) a microphone that detects sounds and outputs acoustic signals representative of said detected sounds; and

(c) a processor means that directly receives said acoustic signals and converts the signals into stimulation signals representative of the detected sounds;

(ii) an electrode array suitable for insertion in the cochlea of an implantee, the array once inserted being adapted to receive the stimulation signals and output electrical stimulation to the implantee'"'"'s auditory nerve; and

(iii) an antenna coil suitable for implantation in the implantee; and

the external device comprises;

(A) an external power source;

(B) an external microphone that detects sounds and outputs acoustic signals representative of said detected sounds;

(C) an external processor means that receives said acoustic signals of said external microphone and generates a coded signal representative of the detected sounds; and

(D) an external antenna coil adapted to inductively couple with the antenna coil of the implantable unit and provide a radio frequency link between the implantable unit and the external device;

wherein the coded signal output by the external processor is transmitted to the electrode array through the radio frequency link.

37. A totally implantable cochlear implant system having an implantable unit comprising:

(i) a hermetically sealed housing including;

(a) a power source that provides the power requirements of the implantable unit;

(b) a microphone that detects sounds and outputs acoustic signals representative of said detected sounds; and

(c) a processor means that directly receives said acoustic signals and converts the signals into stimulation signals representative of the detected sounds;

(ii) an electrode array suitable for insertion in the cochlea of an implantee, the array once inserted being adapted to receive the stimulation signals and output electrical stimulation to the implantee'"'"'s auditory nerve; and

(iii) a deactivation means comprising a resonance circuit, a waveform generator circuit in the housing that outputs a relatively narrow energy waveform that excites the resonance circuit at a regular interval, and a waveform monitoring means that monitors one or more features of the generated waveform following the excitation, wherein any change in the features of the waveform resulting from a metal object being brought to a position adjacent the resonance circuit but external the skin of the implantee are detectable by the monitoring means which, on detection, outputs a signal that at least stops electrical stimulation of the implantee'"'"'s auditory nerve.

38. A totally implantable cochlear implant system having an implantable unit comprising:

(i) a hermetically sealed housing including;

(a) a power source that provides the power requirements of the implantable unit;

(b) a microphone that detects sounds and outputs acoustic signals representative of said detected sounds; and

(c) a processor means that directly receives said acoustic signals and converts the signals into stimulation signals representative of the detected sounds;

(ii) an electrode array suitable for insertion in the cochlea of an implantee, the array once inserted being adapted to receive the stimulation signals and output electrical stimulation to the implantee'"'"'s auditory nerve; and

(iii) a deactivation means that monitors acoustic signals output by the implanted microphone and at least triggers shutdown of electrical stimulation of the implantee'"'"'s auditory nerve on detection of a predetermined type of acoustic signal.

39. The system of claim 38 wherein the predetermined type or acoustic signal is a noise generated on tapping of the skull of the implantee.

40. The system of claim 39 wherein the predetermined type of acoustic signal is a double tap on the skull of the implantee within a predetermined period of time.

41. A cochlear implant system having an implantable unit adapted to work, when necessary, in conjunction with an external device, wherein:

the implantable unit comprises;

(i) a hermetically sealed housing including;

(a) a power source that provides the power requirements of the implantable unit;

(b) a microphone that detects sounds and outputs acoustic signals representative of said detected sounds; and

(c) a processor means that directly receives said acoustic signals and converts the signals into stimulation signals representative of the detected sounds;

(ii) an electrode array suitable for insertion in the cochlea of an implantee, the array once inserted being adapted to receive the stimulation signals and output electrical stimulation to the implantee'"'"'s auditory nerve;

(iii) an antenna coil suitable for implantation in the implantee; and

(iv) a deactivation means comprising a resonance circuit, a waveform generator circuit in the housing that outputs a relatively narrow energy waveform that excites the resonance circuit at a regular interval, and a waveform monitoring means that monitors one or more features of the generated waveform following the excitation, wherein any change in the features of the waveform resulting from a metal object being brought to a position adjacent the resonance circuit but external the skin of the implantee are detectable by the monitoring means which, on detection, outputs a signal that at least stops electrical stimulation of the implantee'"'"'s auditory nerve; and

the external device comprises;

(A) an external power source;

(B) an external microphone that detects sounds and outputs acoustic signals representative of said detected sounds;

(C) an external processor means that receives said acoustic signals of said external microphone and generates a coded signal representative of the detected sounds; and

(D) an external antenna coil adapted to inductively couple with the antenna coil of the implantable unit and provide a radio frequency link between the implantable unit and the external device;

wherein the coded signal output by the external processor is transmitted to the electrode array through the radio frequency link.

42. A cochlear implant system having an implantable unit adapted to work, when necessary, in conjunction with an external device, wherein:

the implantable unit comprises;

(i) a hermetically sealed housing including;

(a) a power source that provides the power requirements of the implantable unit;

(b) a microphone that detects sounds and outputs acoustic signals representative of said detected sounds; and

(c) a processor means that directly receives said acoustic signals and converts the signals into stimulation signals representative of the detected sounds;

(ii) an electrode array suitable for insertion in the cochlea of an implantee, the array once inserted being adapted to receive the stimulation signals and output electrical stimulation to the implantee'"'"'s auditory nerve;

(iii) an antenna coil suitable for implantation in the implantee; and

(iv) a deactivation means that monitors acoustic signals output by the implanted microphone and at least triggers shutdown of electrical stimulation of the implantee'"'"'s auditory nerve on detection of a predetermined type of acoustic signal; and

the external device comprises;

(A) an external power source;

(B) an external microphone that detects sounds and outputs acoustic signals representative of said detected sounds;

(C) an external processor means that receives said acoustic signals of said external microphone and generates a coded/signal representative of the detected sounds; and

(D) an external antenna coil adapted to inductively couple with the antenna coil of the implantable unit and provide a radio frequency link between the implantable unit and the external device;

wherein the coded signal output by the external processor is transmitted to the electrode array through the radio frequency link.