Qualification of unilateral cochlear implant recipients for a second device.

Introduction: Although it is recommended to perform cochlear implantation in both ears at the same time for management of profound hearing loss in children, many centers prefer to perform sequential implantation. There are many reasons as to why a simultaneous bilateral implantation is not commonly accepted and performed. The major risk is the possibility of bilateral vestibular organ impairment. However, it is beyond doubt that children who received the first implant should be given a chance for binaural hearing and associated benefits. In the literature, there are no homogenous criteria for bilateral implantation, and it is hard to find uniform and convincing algorithms for second cochlear implantation. The aim of this study is an attempt to identify a safe way of qualifying for second cochlear implantation in children.
Material and Methods: Forty children with one cochlear implant were qualified for the second implantation. During qualification, the following were taken into account: time of the first implantation, audiometry results, use of the hearing aid in the ear without an implant and benefit of the device, speech and hearing development, and vestibular organ function. R esults: Fifteen out of forty children (38%) were qualified for the second implantation. In 35% of children, the decision was delayed with possible second implantation in the future. Eleven children (27%) were disqualified from the second surgery.
Discussion: During evaluation according to the protocol presented in our study, 38% of children with a single cochlear implant were qualified for the second implantation with a chance for an optimal development and effective use of the second cochlear implant. We are convinced that sequential implantation with a short interval between surgeries and with an examination of the vestibular organ, hearing and speech development as well as an assessment of potential benefits from the second implant (bimodal stimulation) before the second implantation is the safest and most beneficial solution for children with severe hearing loss.