Cochlear Implantation in Common Cavity Deformation

We report on a 4-year-old boy with Townes'-Brock's syndrome including severe inner ear hearing loss. Although the boy started developing speech when using hearing aids this process stopped. Considering cochlear implantation we performed CT scans and found a bilateral common cavity deformation of the cochlea. The facial nerve was in correct position and the internal auditory canal was not enlarged.

Cochlear implantation has been performed successfully in various malformations of the inner ear. Therefore we decided to use a special designed electrode based on the Pulsar CI 100 stimulator (MED-EL, Innsbruck, Austria) for the implantation. This electrode is made longer with a silicone tube strengthened with a wire. The cochlea was approached in the usual way by a posterior tympanotomy and the common cavity was opened in slit shape. In order to avoid malpositioning of the electrode into the vestibular system the electric active middle part of the electrode was inserted as a “U” into the cavity. The opening in the common cavity was sealed with connective tissue with great care as cochlear malformations are associated with an increased incidence of bacterial meningitis.

First results of the cochlear implant fitting will be presented.