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Published on: August 4, 2023
Relationships between bilateral auditory brainstem activity and inter-implant interval in children with cochlear
Yan-Lin Wu1, Li Chen2, Han-Yu Zhu1
1Department of Otolaryngology-Head and Neck Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230001, Anhui, China.
Insights
Sequential bilateral cochlear implants (CIs) show delayed auditory pathway development. A shorter interval between bilateral CIs promotes balanced auditory brainstem pathway maturation.
Area of Science:
- Neuroscience
- Audiology
- Biomedical Engineering
Background:
- Bilateral cochlear implantation (CI) is a common treatment for profound bilateral sensorineural hearing loss.
- The timing of sequential bilateral CI may influence the development of auditory pathways.
Purpose of the Study:
- To examine how the interval between bilateral cochlear implantations affects the maturation of auditory brainstem pathways.
- To compare sequential versus simultaneous bilateral CI using electrically evoked auditory brainstem responses (EABRs).
Main Methods:
- Fifty-eight children with bilateral sensorineural hearing loss were studied.
- 33 received sequential bilateral CIs, 25 received simultaneous bilateral CIs.
- Bilateral EABRs were recorded upon activation of the second CI.
Main Results:
- In sequential CI cases, wave III and V latencies were shorter on the first CI side compared to the second.
- Simultaneous CI showed similar latencies between sides.
- Longer intervals in sequential CI correlated with prolonged latencies and imbalanced pathway development.
Conclusions:
- Unilateral CI use aids ipsilateral auditory pathway maturation.
- Extended intervals between bilateral CIs lead to unbalanced auditory brainstem pathway development.
- Simultaneous or short-interval bilateral CI is recommended for optimal outcomes.
Purpose:
To investigate the effect of the interval between bilateral cochlear implantation on the development of bilateral peripheral auditory pathways as revealed by the electrically evoked auditory brainstem response (EABR).
Methods:
Fifty-eight children with profound bilateral sensorineural hearing loss were recruited. Among them, 33 children received sequential bilateral cochlear implants (CIs), and 25 children received simultaneous bilateral CIs. The bilateral EABRs evoked by electrical stimulation from the CI electrode were recorded on the day of second-side CI activation.
Results:
The latencies of wave III (eIII) and wave V (eV) were significantly shorter on the first CI side than on the second CI side in children with sequential bilateral CIs but were similar between the two sides in children with simultaneous bilateral CIs. Furthermore, the latencies were prolonged from apical to basal channels along the cochlea in the two groups. In children with sequential CIs, the inter-implant interval was negatively correlated with the eV latency on the first CI side and was positively correlated with bilateral differences in the eIII and eV latencies.
Conclusions:
Unilateral CI use promotes the maturation of ipsilateral auditory conduction function. However, a longer inter-implant interval results in more unbalanced development of bilateral auditory brainstem pathways. Bilateral cochlear implantation with no or a short interval is recommended.
