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Updated: May 23, 2025

Cochlear Implant Surgery and Electrically-evoked Auditory Brainstem Response Recordings in C57BL/6 Mice
Published on: January 9, 2019
Cochlear Implantation After Traumatic Brain Injury
Russell W De Jong1, Amanda Y Dao1, James K Aden2
1Department of Otolaryngology-Head and Neck Surgery, San Antonio Uniformed Services Health Education Consortium, JBSA-Ft Sam Houston, San Antonio, Texas, USA.
Objective:
The objective of this study is to determine if a history of traumatic brain injury (TBI) degrades postoperative the audiological performance of patients with cochlear implantation (CI).
Study Design:
Retrospective review.
Setting:
Department of Defense-wide database.
Methods:
International Classification of Diseases, Ninth Revision (ICD-9) and ICD-10 codes were used to identify patients that were diagnosed with TBI prior to CI between 2005 and 2023. They were matched 2:1 with controls without TBI based on age and sex. Preoperative and postoperative pure tone average (PTA) thresholds and AzBio scores were compared.
Results:
Nineteen TBI patients representing 20 implanted ears were identified and matched with 39 patients without TBI representing 40 implanted ears. Thirteen ears carried a diagnosis of mild TBI, and seven were diagnosed with moderate to severe TBI. The average follow-up period was 44 months. The TBI group attained mean postoperative PTA and AzBio scores of 37 dB (SD 24) and 67% (SD 28). The non-TBI group attained scores of 31 dB (SD 12) and 69% (SD 26). P-values for the PTA and AzBio intergroup comparisons were .93 and .88, respectively. All TBI ears attained at least sound awareness after implantation, with 79% achieving open-set speech perception compared to 82% of non-TBI ears.
Conclusion:
CI after TBI of any severity provides hearing rehabilitation comparable to patients without a prior diagnosis of TBI.

