Cochlear Implant Electrode Arrays: The Key to Natural Hearing

The Parts of a Cochlear Implant System

A cochlear implant system consists of an external audio processor and an internal implant. The internal implant has a few different parts, one of which is the electrode array. The electrode array is the long skinny part that extends into the cochlea or inner ear. It contains electrodes that stimulate the inner ear, sending sound signals to the brain.

Electrode Arrays for Everyone

Cochleae vary greatly in length, and that’s why we offer cochlear implant electrode arrays ranging in length up to 34 mm. Electrode arrays that extend deep into the cochlea and provide full cochlear coverage can help MED-EL CI users to hear even the lowest pitches. These are the sounds stimulated toward the innermost part of the cochlea.

MED-EL’s founders have recognized the importance of full cochlear coverage from the very beginning. The first modern cochlear implantation in 1977 was with an implant with a long, flexible electrode array. In 2023, the aptly named 34 mm FLEX34 electrode array, now MED-EL’s longest electrode array, was introduced to the market. This electrode array can provide even more people with access to lower pitches in a more natural way.

FLEX Electrode Arrays

FLEX electrode arrays range in length from 20 mm to 34 mm. Their name comes from the fact that these free-fitting arrays are exceptionally flexible. This is thanks to wave-shaped wires, optimal electrode spacing, and FLEX-Tip technology.

Free-fitting arrays make a more atraumatic insertion possible—one that does not damage inner ear structures. This can help preserve residual hearing. And that also means you are more likely to be able to benefit from future hearing technologies.

Designed for Your Safety

The wave-shaped wires are made of a platinum-iridium alloy. And they are encased in silicon, which is biocompatible and very long-lasting. Another feature that makes insertion more atraumatic is the design of the electrode array’s tip. It is very thin—only 0.5 x 0.4 mm in diameter.

Because your well-being is our top priority, there is an independent safety capacitor for each electrode channel. Safety capacitors block dangerous direct current to ensure our cochlear implants provide only safe stimulation. This is just one of many design aspects that contribute to the outstanding safety and reliability of cochlear implants from MED-EL.

Electrodes for Every Anatomy

Not all cochleae have the same shape, and hearing loss is often associated with other otological complications that cause malformations. That means some people need options other than FLEX electrode arrays to fit the unique anatomy of their ear.

One different kind of array is a compressed electrode array. They are much shorter than typical electrode arrays—only 15 mm long—but still contain 12 sets of electrode contacts, so you can hear a wide range of pitches.

When there is a risk of cerebrospinal fluid leakage after implantation, MED-EL offers two FORM electrode array options, 24 or 19 mm long. The cork-shaped SEAL design at the base of these electrode arrays helps create a seal at the cochlear opening to prevent leakage.

These are just some of MED-EL’s electrode array options. Your surgeon can work with MED-EL to find the ideal hearing solution for you.

Choosing the Right Electrode

But how will your surgeon know which electrode array is the right one for your unique cochlea? With the help of OTOPLAN software developed specifically for MED-EL hearing devices, it’s easy. Read more about OTOPLAN and how your surgeon can use it to individualize your cochlear implant and provide you with closest to natural hearing.