CI: 1 day out – what is it? (Part 1)

With less than twenty-four hours to go until surgery, I suppose it’s about time to get into the details of cochlear implants. It is a two step process. First, surgery to implant the internal processor and electrode array. Second, after a few weeks of recovery, the external processor is fitted and configured. I’ll cover the second part in a later post.

Just what is this new piece of shiny that will be forever embedded in my head?

Another angle with a nickel for size reference:

The function of that beautiful thing is to send electrical pulses down the electrode wire to the array. The coil receives both power to operate the implant and the digitized processed audio signal from the external processor, via an external coil. Both coils have magnets in the center to hold the external one in place.

Each of the sixteen contact points on the array are driven by a separate output circuit, which allows multiple contact points to be fired simultaneously (I will cover why that is a good thing in part 2).

How does it get implanted? First, here’s some artwork showing the placement of the implant:

Tomorrow my wife and I head to the hospital for a 7:15 am check-in. Surgery is scheduled for 10 am and usually takes from 3 to 4 hours. I’m not sure I have the exact sequence of events right, but the general flow of events is as follows. A small incision an inch or so in length is made just behind my left ear, which is then spread open. To accommodate the processor, a shallow divot is drilled into the area of my skull back from the ear a bit and about level with the top of the ear. Next some bone is removed just behind the ear allowing access to the middle ear and cochlea. This is a delicate process since a main facial nerve is located there. Electrodes attached to my face are monitored to help ensure the nerve is not affected. The processor is inserted under the scalp and muscles. A small opening is made in the cochlea and the electrode array is fed through it. Once everything is in place, several tests are run to ensure the array is stimulating my hearing nerve. My ear is put back where it’s supposed to be and the incision is closed up. Some nice goop over the incision creates a protective water-impermeable barrier and a big pressure bandage goes over that. Then it’s off to the recovery area to be monitored until I wake up. After about an hour I’ll be wheeled to a room. If I’m not suffering any nasty side-effects like bad vertigo, etc., after a couple of hours they will remove my bandage and kick me out the door at about 5 pm.

The following few days I will spend at home popping Keflex (antibiotic) and Vicodins for pain (if necessary), and following the instructions I noted in my previous post. And I will do my best to chronicle the recovery process here.

Now, it’s time to go have my last meal for the next 24 hours. They like you hungry for surgery!