Effect of cochlear implantation on middle ear function: A three-month prospective study.

OBJECTIVES/HYPOTHESIS: To determine if cochlear implantation has a delayed effect on the middle ear conductive hearing mechanism by measuring laser Doppler vibrometry (LDV) of the tympanic membrane (TM) in both implanted and contralateral control ears preoperatively and 3 months postoperatively, and then comparing the relative change in LDV outcome measures between implanted and control ears.

STUDY DESIGN: Prospective cohort study.

METHODS: Eleven preoperative adult unilateral cochlear implant recipients in previously unoperated ears with normal anatomy and aerated temporal bones were included in this study. The magnitude and phase angle of umbo velocity transfer function in response to air- conduction (AC) stimulus, and the magnitude of umbo velocity in response to bone- conduction (BC) stimulus were measured in the implant ear and the contralateral control ear preoperatively and 3 months postoperatively and compared.

RESULTS: No significant changes in the magnitude or phase angle of TM velocity in response to either AC or BC stimulus were observed in the implanted ear relative to the contralateral control ear 3 months following cochlear implantation.

CONCLUSIONS: From the results of LDV measurements, it can be said that cochlear implantation has no significant delayed effect on the middle ear conductive mechanism.

LEVEL OF EVIDENCE: 4. Laryngoscope, 128:1207-1212, 2018.