What Is an Individualized Cochlear Implant?

When we say individualized cochlear implant, we’re talking about a specific part of the implant: the electrode array. The electrode array is the wire at the end, which is inserted into your cochlea during surgery. The electrode contacts along this wire stimulate the nerve cells in your cochlea, sending sound signals to your brain that allow you to hear.

How long should your electrode array be? Higher frequencies are stimulated at the base or entrance of the cochlea, and lower pitches are stimulated further along the cochlea toward the apex. To ensure that you can hear a full spectrum of sound, your cochlear implant’s electrode array should be long enough to cover your entire cochlea. If the electrode array is too short, you might not hear lower bass tones, causing things to sound unnatural and making it hard to hear properly.

Electrode Array Lengths

But cochleae come in many shapes and sizes. You’re more likely to have the same size feet as somebody else than the same size cochlea. When you go to the shoe store, there is a range of different sizes available so you can choose the ones that fit your feet. It doesn’t make sense to have shoes that are “one size fits all,” and it also doesn’t make sense to have “one size fits all” cochlear implants. MED-EL offers a wide variety of cochlear implant arrays in a range of different lengths so your surgeon can choose the one that best fits your unique cochlea.

How do they do that? First they have to measure your cochlea. That’s easy with OTOPLAN software.  Using the exact measurements provided by OTOPLAN, your surgeon can quickly see which electrode array is right for your individual cochlea.

Flexible Electrode Arrays

MED-EL’s FLEX series of electrode arrays are designed to preserve the delicate structures in your inner ear. These free-fitting arrays gently bend to adapt to the unique shape of your cochlea. They contain wave-shaped wires that bend more easily than straight wires. And the electrodes in the array are spaced optimally for mechanical flexibility and to avoid stimulating overlapping parts of the cochlea.

Solutions for Difficult Anatomies

Other factors besides length and flexibility can be important for some CI candidates. Many people with hearing loss have malformed or ossified cochleae, and a regular electrode array may not be the best fit. But MED-EL has designed electrode arrays that can work for you even if your cochlea is like this.

If your cochlea is malformed and doesn’t have much space for an implant, your surgeon could go for a shorter compressed electrode array. Or if there is a risk of cerebrospinal fluid leakage, they could choose a FORM electrode array. And those are just a few of the many options manufactured by MED-EL. Your surgeon might even bring several electrode arrays to the surgery. That’s how Mary Beth’s surgeon chose the right implant for her.

Activation and Pitch-Perfect Fitting

The next steps after surgery are activation and fitting with your audiologist. Activation is when your audio processor is turned on for the first time and you can hear with your new individualized cochlear implant from MED-EL. Your audiologist will be able to “fit” your CI—a bit like “tuning” each electrode—to individualize your cochlear implant and optimize your hearing even further.

Want to know which individualized cochlear implant is right for you? Contact your nearest clinic for more information about individualized cochlear implants.

And meet the man behind MED-EL’s electrodes in this exclusive interview with electrode wizard, Claude Jolly.

You can also find out more about how cochlear implants work and how they could help you or your child on our website.