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.
Keywords: Otolith function, Cochlear implantation, Inner ear
malformation, Pediatric, Balance function
Key Points
There is limited studies on otolith function in patients
with IEMs before and after cochlear
implants (CI).
We conducted a prospective study of otolith function with IEMs using
vestibular evoked myogenic potentials (VEMP).
We included 78 children (41 females and 37 males) who underwent CI, all
patients were divided into two groups based on the presence (IEM group)
or absence of IEMs (control group)
The IEM group had a lower response rate of cVEMP
(X2 =4.768, p =0.003) and oVEMP
(X2 =4.408, p =0.003) compared to the
control group. The abnormal cVEMP and oVEMP rate after surgery was
increased in the control group (p< 0.001) but decreased
in the IEM group.
Evaluating the otolith and balance functions before CI is necessary and
should be considered in clinical practice.