High contact count, sub-miniature, fully implantable cochlear prosthesis

• US 6,826,430 B2
• Filed: 03/30/2001
• Issued: 11/30/2004
• Est. Priority Date: 03/31/2000
• Status: Expired due to Fees

• Current Assignee: Advanced Bionics AG (Sonova Holding AG)
• Original Assignee: Advanced Bionics Corporation (Sonova Holding AG)
• Inventors: Griffith, Glen A., Faltys, Michael A., Harrison, William Vanbrooks
• Primary Examiner(s): Schaetzle, Kennedy
• Assistant Examiner(s): DROESCH, KRISTEN L
• Application Number:
  US09/823,271
• Publication Number:
  US 20010031909A1
• Time in Patent Office: 1,341 Days
• Field of Search: 607/1-2, 607/30-32, 607/55-57, 607/59-60, 607/115-116, 607/137, 600/379, 623/379, 623/10
• US Class Current: 607/137
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/37217 characterised by the communication link, e.g. acoustic or tactile
• CPC Class Codes: A61N 1/37223 Circuits for electromagnetic coupling
• CPC Class Codes: A61N 1/3727 characterised by the modulation technique

Abstract

A fully implantable cochlear prosthesis includes (1) an implantable hermetically sealed case wherein electronic circuitry, including a battery and an implantable microphone, are housed, (2) an active electrode array that provides a programmable number of electrode contacts through which stimulation current may be selectively delivered to surrounding tissue, preferably through the use of appropriate stimulation groups, and (3) a connector that allows the active electrode array to be detachably connected with the electronic circuitry within the sealed case. The active electrode array provides a large number of both medial and lateral contacts, any one of which may be selected to apply a stimulus pulse through active switching elements included within the array. The active switching elements included within the array operate at a very low compliance voltage, thereby reducing power consumption. The entire prosthesis is very efficient from a power consumption standpoint, thereby allowing a smaller battery to power the system for longer periods of time before recharging or replacement is required. The hermetically sealed case within which the electronic circuitry, battery, and microphone are housed may be replaced, when needed, through minimally invasive surgery. Further, the electronic circuitry housed within the hermetically sealed case may be programmed, as needed, using acoustic and/or RF control signals. In one embodiment, such control signals may be realized using phase-shift keyed (PSK) modulation of an acoustic signal within a very narrow frequency band centered at about 6 KHz.

Claims

1. An implantable tissue stimulation prosthesis comprising:

an implantable hermetically sealed case;

an active electrode array external to the hermetically sealed case comprising at least four active electrodes, wherein each active electrode includes first and second electrode contacts, decoding circuitry, a first switch coupled to the decoding circuitry and the first electrode contact, and a second switch coupled to the decoding circuitry and the second electrode contact, and wherein the decoding circuitry responds to electrode control signals and causes the first and second switches to selectively activate one or both of the first or second electrode contacts, and further wherein the first and second electrode contacts of each active electrode comprise at least one lateral electrode contact and at least one medial electrode contact;

a battery carried within said sealed case; and

electronic circuitry housed within said sealed case, said electronic circuitry including telemetry circuitry that receives programming signals from an external source, processing circuitry that generates the electrode control signals, control circuitry that applies the electrode control signals to the switching circuitry of the active electrode array, and pulse generation circuitry that generates stimulation currents that are applied through selected ones of the first and second electrode contacts of the active electrodes of the electrode array.

2. An implantable tissue stimulation prosthesis comprising:

an implantable hermetically sealed case;

an active electrode array external to the hermetically sealed case, comprising at least four active electrodes, wherein each active electrode includes switching circuitry and at least one lateral electrode contact and at least one medial electrode contact that may be individually activated by electrode control signals applied to the switching circuitry;

wherein the switching circuitry of each active electrode comprises decoding circuitry, a first switch coupled to the decoding circuitry and the at least one lateral electrode contact, and a second switch coupled to the decoding circuitry and the at least one medial electrode contact, wherein the decoding circuitry responds to the electrode control signals and causes the first and second switches to selectively activate one or both of the medial or lateral electrode contacts;

a battery carried within said sealed case; and

electronic circuitry housed within said sealed case, said electronic circuitry including telemetry circuitry that receives programming signals from an external source, said electronic circuitry further including circuitry that generates the electrode control signals and that applies the electrode control signals to the switching circuitry of the active electrode array, and that further generates stimulation currents that are applied through selected ones of the plurality of individual electrodes of the active electrode array.

3. The implantable tissue stimulation prosthesis of claim 2 wherein the decoding circuitry and first and second switches of an active electrode are formed on a suitable substrate die, and wherein the medial and lateral electrode contacts of the active electrode are formed on opposing edges of the substrate die, and wherein at least four of said substrate dies are stacked and over-molded with silastic to form the active electrode array.

4. The implantable tissue stimulation prosthesis of claim 3 wherein the active electrode array comprises a plurality of active electrode banks, wherein each active electrode bank includes a plurality of active electrodes.

5. The implantable tissue stimulation prosthesis of claim 4 wherein at least one active electrode in each active electrode bank includes a built-in strain gauge, wherein the strain gauge is adapted to measure stress across the substrate die.

6. A fully implantable tissue stimulation prosthesis comprising:

an implantable hermetically sealed case;

an implantable microphone;

an active electrode array external to the hermetically sealed case, comprising at least a plurality of medial electrode contacts, a plurality of lateral electrode contacts, and switching circuitry, and wherein at least one of said plurality of medial electrode contacts or at least one of said plurality of lateral electrode contacts may be individually activated by electrode control signals applied to the switching circuitry, and wherein the switching circuitry and lateral and medial electrode contacts are formed on a silicon die, and wherein a plurality of said silicon dies are stacked and over-molded with silastic to form the active electrode array;

a battery carried within said sealed case; and

electronic circuitry housed within said sealed case for receiving and processing signals from said microphone, for generating the electrode control signals, and for generating stimulation currents, and for applying the electrode control signal and stimulation currents to the active electrode array through feed-through connectors.

7. The prosthesis as set forth in claim 6 further including a connector through which said active electrode array is detachably connected to the electronic circuitry in said hermetically sealed case.

8. A fully implantable tissue stimulation prosthesis comprising:

an implantable hermetically sealed case;

an implantable microphone;

an active electrode array external to the hermetically sealed case, comprising at least one electrode group and associated switching circuitry, wherein the at least one electrode group includes a plurality of individual electrodes comprising at least one lateral electrode contact and at least one medial electrode contact that may be individually activated by electrode control signals applied to the switching circuitry, wherein the switching circuitry responds to the electrode control signals to selectively activate one or both of the medial or lateral electrode contacts, and further wherein the switching circuitry and lateral and medial electrode contacts are formed on a silicon die, and wherein a plurality of said silicon dies are stacked and over-molded with silastic to form the active electrode array;

a connector through which said active electrode array is detachably connected to the electronic circuitry in said hermetically sealed case;

a battery carried within said sealed case;

electronic circuitry housed within said sealed case for receiving and processing signals from said microphone, for generating the electrode control signals, and for generating stimulation currents, and for applying the electrode control signals and stimulating currents to the active electrode array through feed-through connectors, wherein the stimulation currents are applied through selected groupings of the plurality of individual electrodes.

9. The prosthesis as set forth in claim 8 wherein the switching circuitry included within the active electrode array is adapted to operate at a low compliance voltage, thereby reducing power consumption.

10. The prosthesis as set forth in claim 8 wherein the electronic circuitry housed within the sealed case includes both analog and digital circuitry.

11. The prosthesis as set forth in claim 8 further including an RF coil for receiving and sending RF signals to and from the electronic circuitry housed within the sealed case.

12. The prosthesis as set forth in claim 11 wherein RF signals received through the RF coil provide operating power to recharge the battery housed within the sealed case.

13. The prosthesis as set forth in claim 12 wherein the active electrode array is adapted for insertion into a human cochlea, and wherein the stimulation currents are applied through selected electrode groupings as controlled by the electrode control signals and the switching circuitry of the active electrode array in order to provide the sensation of hearing for a user of the prosthesis.

14. The prosthesis as set forth in claim 13 further including means for adjusting operating parameters of the electronic circuitry through the use of acoustic remote control signals received through the microphone.

15. The prosthesis as set forth in claim 14 wherein the acoustic control signals comprise phase-shift keyed (PSK) modulation of an acoustic signal within a narrow frequency band.

16. The prosthesis as set forth in claim 15 wherein the narrow frequency band is centered at about 6 KHz.

17. The prosthesis as set forth in claim 8 wherein the electronic circuitry further includes means for determining a simultaneous N-of-M strategy to be applied by the prosthesis.

18. The prosthesis as set forth in claim 8 wherein the electronic circuitry further includes a plurality of pulse generator circuits and means for defining a pulse table that drives the pulse generator circuits.

19. A fully implantable cochlear prosthesis comprising:

an implantable hermetically sealed case wherein is housed;

electronic circuitry;

a battery;

a microphone;

wherein the battery provides operating power for the electronic circuitry and the microphone is operatively connected to the electronic circuitry;

an active electrode array connected to the electronic circuitry within the sealed case, wherein the active electrode array includes a programmable number of electrode contacts through which stimulation current may be selectively delivered to surrounding tissue; and

a connector that allows the active electrode array to be detachably connected with the electronic circuitry within the sealed case;

wherein the active electrode array includes active switching elements and a multiplicity of both medial and lateral electrode contacts, any one of which may be selected to apply a stimulation current through the active switching elements included within the array, and

wherein the active switching elements comprise decoding circuitry, a first switch coupled to the decoding circuitry and at least one of said lateral electrode contacts, and a second switch coupled to the decoding circuitry and at least one of said medial electrode contacts, and wherein the decoding circuitry responds to the electrode control signals and causes the first and second switches to selectively activate one or both of the medial or lateral electrode contacts.

20. The fully implantable cochlear prosthesis of claim 19 wherein the active switching elements included within the active electrode array are adapted to operate at a low compliance voltage, thereby reducing power consumption.

21. The fully implantable cochlear prosthesis of claim 20 wherein the battery is rechargeable, and wherein the electronic circuitry included within the sealed case includes recharging circuitry that receives power from an external source for recharging the battery.

22. The fully implantable cochlear prosthesis of claim 19 wherein the electronic circuitry housed within the hermetically sealed case includes programmable circuitry that is adapted to be reprogrammed using externally generated programming signals.

23. The fully implantable cochlear prosthesis of claim 22 wherein the programming signals are selected from the group comprising acoustic and RF signals.

24. The fully implantable cochlear prosthesis of claim 23 wherein the programming signals comprise an acoustic signal that is phase-shift keyed (PSK) modulated within a frequency band centered at about 6 KHz.