Comparison of electrode position between round window and cochleostomy inserting approaches among young children: a cone-beam computed tomography study

Abstract

Background: As the two most commonly used approaches for cochlear implants (CIs), the round-window insertion (RWI) and cochleostomy are still controversial about which approach is optimal. The lack of visual observation methods makes it difficult to compare the electrode position between them.Objectives: To evaluate and compare the electrode position between RWI and cochleostomy approaches for CI among young children.Materials and methods: Twenty-four patients (16 male, 8 female) accepting CI and temporal cone-beam computed tomography (CBCT) scan post-operation in our hospital from January 2016 to July 2017 were analyzed retrospectively. Operative notes and images were used to identify the surgical technique. Mainly depending on the round-window exposure, 15 cochleae were performed with RWI and 11 performed with cochleostomy.Results: Mean age, 2.4 (range 0.8–7) years. The CBCT images showed that all the electrode arrays were located in scala tympani. There were no significantly statistical differences in the distance between electrode contacts and modiolus (EMI), intracochlear insertion length and the angle of electrode arrays at the insertion site of the cochlea.Conclusions and significance: Both approaches could insert electrodes into scala tympani satisfactorily. As electrodes and cochlear structures could be clearly visualized, CBCT can be applied to assess the electrode position reliably.