Optimizing cochlear implant electrode selection

• US 6,915,166 B1
• Filed: 08/28/2000
• Issued: 07/05/2005
• Est. Priority Date: 08/27/1999
• Status: Expired due to Term

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Cafarelli-Dees, Denise, Laszig, Roland, Nicolai, Jochen, Dillier, Norbert, Von Wallenberg, Ernst Ludwig, Mueller-Delle, Joachim, Lai, Wai Kong, Stecker, Mathias
• Primary Examiner(s): LAYNO, CARL HERNANDZ
• Application Number:
  US10/009,044
• Time in Patent Office: 1,772 Days
• Field of Search: 607/45, 607 55- 57, 600/25, 623/10
• US Class Current: 607/55
• CPC Class Codes: A61N 1/36038 Cochlear stimulation

Abstract

A method is described to allow for better selection of electrodes for neural stimulation, for example in a cochlear implant. A series of stimuli, at different stimulation levels, are provided at each electrode to be tested, and the neural response to each stimulus is measured, using an implanted electrode. A value is then calculated relating stimulus level to response, to allow the relative responsiveness of electrodes to be determined. This can then be used as the basis for a stimulation map used to select which electrodes are stimulated and at what level.

Claims

1. In a multi-electrode neural stimulation system, a method for determining which electrodes are working well or poorly, including the steps of:

(a) providing a series of stimuli using each electrode,

(b) measuring the neural response to said stimuli using said electrodes, said stimuli having different stimulus levels;

(c) calculating a value relating stimulus level to response level for each electrode; and

(d) determining whether said electrode is working by comparing said electrode'"'"'s value of step (c) with the values of step (c) for each electrode.

2. A method according to claim 1, wherein the electrodes used for measurement are one or more of the stimulating electrodes.

3. A method according to claim 1, wherein the system is an intra-cochlear prosthesis.

4. A method according to claim 3, wherein the neural response measured is the amplitude of evoked neural response.

5. A method for determining the relative responsiveness of electrodes in a multi-electrode intracochlear prosthesis, including the steps of

(a) measuring the amplitude of the evoked response to a set of stimuli at different stimulation levels for one of the electrodes in said prosthesis;

(b) calculating a value relating the evoked responses to the stimulus levels for each electrode;

(c) repeating steps (a) and (b) for each electrode for which data is required; and

(d) determining the relative responsiveness of the electrodes by comparing the values of step (b) for the tested electrodes.

6. A method according to claim 5, wherein step (b) is performed by deriving the slope of the best fit regression line on a plot of stimulus level against peak to peak amplitude of evoked response.

7. A method according to claim 6, wherein step (b) is performed by deriving the value of the peak to peak amplitude of said evoked response.

8. A method according to claim 5, wherein the relative responsiveness according to step (d) is used to construct an electrode map for selecting electrodes for stimulation.

9. A method according to claim 8, wherein the electrode map is modified in response also to the spectral distribution of the most responsive electrodes, so as to provide a more even distribution of electrodes selected for stimulation.