Related Experiment Video
Updated: Jul 8, 2025
Using Unidirectional Rotations to Improve Vestibular System Asymmetry in Patients with Vestibular Dysfunction
Published on: August 30, 2019
Long term effects of cochlear implant surgery on vestibular system in pediatric population
Ata Alperen Erşahan1, Hasan Mervan Değer1, Merve Durgut1
1Kocaeli University, Medical Faculty, Otorhinolaryngology Department, Izmit, Kocaeli, Turkey.
Insights
Cochlear implant surgery can affect the vestibular system, particularly the anterior semicircular canal, even years later. However, implant use (on/off) or type (unilateral/bilateral) did not significantly alter vestibulo-ocular reflex gains after one year.
Area of Science:
- Otolaryngology
- Neuroscience
- Audiology
Background:
- Cochlear implants (CIs) are vital for hearing restoration but may impact the vestibular system.
- Understanding the long-term effects of CIs on vestibular function is crucial for patient management.
Purpose of the Study:
- To evaluate the vestibular system's vestibulo-ocular reflex (VOR) gains in pediatric CI users.
- To compare VOR gains between unilateral and bilateral CI users and a healthy control group.
- To assess the influence of CI status (on/off) on VOR gains.
Main Methods:
- Video head impulse testing (VHIT) was used to measure VOR gains in the three semicircular canals.
- The study included 24 unilateral and 13 bilateral CI users (CI duration >1 year) and 30 controls.
- VOR gains were assessed with CIs both on and off.
Main Results:
- CI users showed significantly lower VOR gains in the anterior semicircular canal compared to controls (p < 0.05).
- No significant differences in VOR gains were found between unilateral and bilateral CI users.
- CI status (on or off) did not impact VOR gains, nor did usage time or age at implantation.
Conclusions:
- Cochlear implantation can have lasting effects on the vestibular system.
- Vestibular function, as measured by VOR gain, remains stable after the first year post-implantation.
- Bilateral cochlear implantation does not appear to cause additional vestibular dysfunction compared to unilateral implantation.
Objective:
The aim was to evaluate the vestibular system of children who had undergone cochlear implant surgery and to compare them with the healthy population by vestibulo-ocular reflex (VOR) gains in unilateral and bilateral implant users, with the implants both on and off.
Methods:
Patients older than 5 years who had undergone cochlear implant surgery between 2012 and 2020 and who were cochlear implant users for at least one year were included. After consent was obtained, a video head impulse test (VHIT) was performed to evaluate the three semicircular canals, with devices on and off, and VOR gains were evaluated. VHIT was also used to assess VOR gains in the control group. The VOR gains of the study and control groups, VOR gains of unilateral and bilateral implant users, and VOR gains with implants on and off were compared.
Results:
When the VOR gains of 24 unilateral and 13 bilateral cochlear implant users and the control group (n = 30) were compared, a significant difference was found only in the anterior semicircular canal, although the VOR gains were found to be low in all three semicircular canals in the implant users (p < 0.05). There was no significant difference between the VOR gains of unilateral and bilateral implant users. There was no significant difference between the VOR gains when either on or off. There was no correlation between cochlear implant usage time, implant insertion age, patient age and VOR gain.
Conclusion:
The effects of cochlear implant surgery on the vestibular system continue in the late period, but no correlation was observed between implant usage time and VOR gain after the first year. It was observed that having the cochlear implant on or off had no effect on VOR gain. Furthermore, bilateral implant surgery did not lead to additional vestibular dysfunction compared to unilateral implant surgery.
Related Concept Videos
01:15Equilibrium and Balance
01:16Anatomy of the Ear