Background: After introducing the first Cochlear Implants also in children theses are grown with electrical intracochlear stimulation and subsequent auditory cortical development. Over the meantime the positioning of the electrode was changed orientated on the development of electrode design, ability to insert atraumatic and on the widening of the indications towards highfrequency deafness.
Methods: In this pilot study we analysed five prelingually deafened patients implanted as child in the late 90's and had a reimplantation 2016 or later. We compared CT and DVT (cone beam CT) scans of the temporal bone and measured the insertion angle, the cochlear coverage, the total length of the electrode in the cochlea and the distance of the first active electrode to the round window. Moreover, we compared their speech understanding before and after reimplantation.
Results: The results show a lowering in the insertion angle, the cochlear coverage, the total length of the electrode in the cochlea, in the distance of the first active electrode to the round window and in the speech understanding after reimplantation.
Conclusion: These results show a difference in the depth of insertion while the speech understanding is not significantly improving in this group-although the technology is advanced. The influence of auditory maturation with CI in these patients will be discussed.
Keywords: Cochlear implant; Depth of insertion; Insertion angle; Reimplantation.