Lessons learned in delayed identification of a misplaced electrode array in the vestibule

Area of Science:

• Otolaryngology
• Neurosurgery
• Audiology

Background:

• Cochlear implantation is a common treatment for profound hearing loss.
• Accurate electrode placement is crucial for optimal device function.
• Electrode misplacement, particularly in the vestibule, can lead to suboptimal outcomes.

Purpose of the Study:

• To report a case of cochlear implantation with electrode array misplacement in the vestibule.
• To investigate the reasons for the delayed identification of this misplacement.
• To highlight the importance of considering atypical presentations in cochlear implant recipients.

Main Methods:

• A 23-year-old male with single-sided deafness underwent cochlear implantation.
• Intraoperative assessment and postoperative audiological evaluations were performed.
• High-resolution computed tomography (HRCT) and neural response telemetry (NRT) were utilized for diagnosis.
• Revision surgery was conducted.

Main Results:

• The electrode array was found entirely within the vestibule on HRCT.
• The patient exhibited poor speech performance despite good aided hearing thresholds.
• Retrospective NRT analysis showed subtle response differences.
• The patient did not present with vestibular symptoms due to pre-existing otolithic weakness.

Conclusions:

• Delayed identification of electrode misplacement can occur, even without typical vestibular symptoms.
• Atypical presentations necessitate thorough investigation, including advanced imaging and electrophysiological testing.
• Further research is needed to understand outcomes in cases of electrode misplacement within the vestibule.