Otolith and balance function evolution related to cochlear implantation
in hearing loss with inner ear malformations
Abstract
Objectives: In recent years, with the incidence of bilateral
cochlear implantation (CI) increasing, understanding the impact of CI on
otolith function is of greater necessity. This study aims to investigate
the development of gross motor and otolith function in patients with
inner ear malformations (IEMs) by vestibular evoked myogenic potentials
(VEMP). Materials and Methods: A total of 78 patients with
sensorineural hearing loss (SNHL) (age 5.7±4.1 years) were divided into
two groups based on the presence (IEM group, n=39) or absence (control
group, n=39) of IEMs. VEMP was conducted before and 1–3 months after
CI, and gross motor development assessed. Results: The mean
ages of head control and independent walking were delayed in the IEM
group compared with control group ( p=0.02). The preoperative
cVEMP and oVEMP response rates were higher in the control groups (60%
and 86.95%) than in the IEM group (57.69% and 74.35%) (
p<0.05). Additionally, abnormal cVEMP was associated
with delayed acquisition of independent walking ( p=0.017).
Saccular and utricular functions after CI were lost by 40% and 31.75%,
respectively, in group of patients present preoperatively VEMPs waveform
(n=25). Conclusions: Balance development is more reduced in
patients with SNHL and IEMs than in patients without IEMs. The
otolith-vestibular nerve conduction pathway can be affected by CI and
lead to otolith function impairment. As such, evaluating the otolith and
balance functions before CI is necessary and should be considered in
clinical practice.