Early-Term Effect of Bilateral Sequential Cochlear Implantation on the Audiovestibular Function of Paediatric Patients: A Prospective Pilot Study.

BACKGROUND/

OBJECTIVES

Sequential bilateral cochlear implantation is being increasingly considered in paediatric patients with bilateral profound hearing loss, particularly when the contralateral ear shows limited residual hearing or poor speech discrimination. Although auditory benefits of a second cochlear implant (CI2) have been reported, concerns remain regarding possible vestibular impairment after surgery. This study aimed to provide a preliminary prospective evaluation of early audiological and vestibular outcomes in children undergoing sequential bilateral cochlear implantation and to explore whether the age at implantation or the inter-implant interval influenced longitudinal trajectories.

METHODS

Ten children with prelingual bilateral profound sensorineural hearing loss who underwent sequential bilateral cochlear implantation were prospectively enrolled. Assessments were performed at baseline and during follow-up up to 12 months after CI2 activation. The audiological evaluation included pure-tone audiometry, speech recognition in quiet with CI2 alone and bilaterally, and speech-in-noise testing in frontal and lateralised configurations. The vestibular evaluation included static stabilometry and video head impulse testing. Patient-reported outcomes were assessed using the speech, spatial and qualities of hearing scale for children. Longitudinal changes were analysed using mixed-effects models with false discovery rate correction.

RESULTS

Unilateral speech recognition with CI2 improved significantly over time, with median word recognition increasing from 0% at 3 months to 60% at 12 months (p < 0.0001; q = 0.0001). The speech-in-noise performance also improved significantly in the frontal and F1C configurations. Bilateral speech recognition in quiet remained stable at high levels, consistent with a ceiling effect. The vestibular measures were broadly stable at the group level, and the SSQ scores showed modest, non-significant changes. Exploratory analyses did not identify consistent effects of the implantation age or inter-implant interval on longitudinal trajectories.

CONCLUSIONS

Sequential bilateral cochlear implantation was associated with early auditory benefit, particularly for CI2 unilateral performance and speech perception in noise, without evidence of major short-term vestibular deterioration.