Bilateral Cochlear Implants
As of May, 2005, Brendan uses two cochlear implants -- one for each ear. While he is hearing with his "new" ear, he cannot currently make enough sense of the sounds from his left ear alone to understand language. We've been told to expect slow, but steady progress.
The process of "ramping up" the new ear is much like we experience with his first implant -- start softly, and increase the volume, sensitivity, and dynamic range over time.
So why two implants when one works well enough?
Current data indicates that he should be able to eventually localize sounds to within about 45 degrees (typically hearing people can resolve to about 2 degrees). Besides being able to tell which way a sound is comming from, this ability is critical to support listing in noisy environments. We use our bilateral hearing to "focus" in on the sounds we need to hear.
In addition, a second implant gives Brendan an upgrade path should he choose to use it later in life. If dramatically new technology comes along, he will have the opportinity to replace one side without risk of completely losing all hearing.
Update As of September, 2005. Brendan is certainly hearing much better than ever before. I'm starting to detect some signs of his being able to localize sound, but it's hard to be certain about this.
Categories: cochlear_implants
