4 DISCUSSION
Despite CI success in children with IEMs, the results were highly
variable. In this study, we aimed to determine the success of auditory
perception skills in these children over the years. The study had one of
the largest series of 137 using CI children with IEMs and reported
auditory perception outcomes. CT and MRI have played a critical role in
the diagnosis of children with ear abnormalities; thus, surgical
planning has been facilitated. However, after the surgery, it was
crucial to show up the functional hearing levels of all using CI
children and to know how long they have achieved their development. The
auditory perception outcomes of different types of IEMs have been
compared in studies.
Children with IEMs were found to develop identification and
comprehension toward environmental sounds and speech sounds after an
average one year. The results indicated a delay in auditory perception
performance in children with inner ear anomaly; however, their
performance changes with time. It is necessary to follow more closely
and to study in this direction in terms of the functionality of auditory
perception performances. Although the auditory performances of children
with IEMs were better in the closed-set test, their vocabulary was weak,
and it was observed that they had struggled in attention and memory
skills during the evaluation. Open-set tests involve thinking and
predicting words in sentences using clues in the context to maintain the
conversation; therefore, the use of language-based visual clues would be
complicated skill to develop. 10
The ten children who common cavity, incomplete partition, EVA, and
membranous anomalies, in Luntz et al,12 the study
demonstrated speech awareness at 25 dB HL or better. They reported that
children with IEMs had more than 30 months of CI experience, and 75% of
those achieved some degree of open-set sentence recognition. Dowell et
al,13 showed that children implanted before the age of
four years had mean scores of 68% for open-set phonemes after three to
five years of experience with the cochlear implant. The present study
results showed that after one-three years of CI experience, children
with IEMs have succeeded in the closed-set test, but not in the open-set
SRT test.
Overall IEMs, the EVA group had a higher score than normal cochlea in
the closed-set test. The EVA was a congenital anomaly with progressive
sensorineural hearing loss. In the beginning, their hearing may be
normal, but the process is progressive. It was thought children with EVA
might have been suffering from HL in the peri- or post-lingual period
rather than the prelingual period. EVA was better than IP-II because of
the better than the modiolar defect, which is the reason to make the
outcome slightly worse. EVA, IP-II, IP-III had comparable results with
normal cochlea; this is because a good-sized cochlear nerve always
accompanies them. ABI surgery is never indicated in EVA, IP-II, and
IP-III. Some studies in the literature have shown that children with EVA
exhibited high performance in auditory perception
testing.14-16
As higher-level language skills had increased, it had been determined
that children with IEMs (especially common cavity and cochlear
hypoplasia) have difficulty with comprehension skills. Results indicate
that the duration of CI use is significant than the chronological age
for both receptive and expressive language development. As the child’s
chronological age increases, the gap between language skills scores
wider. In later years, it will be challenging to learn comprehensive
language skills and catch these tasks.17Tucci et
al,18 reported the same finding in their study with
five children and one adult. All patients except one demonstrated
limited language skills.In another study, researchers presented speech
perception and production after follow-up for 36 months in children with
common cavity scores for the CAP, SIR, MAIS, and closed-set/open-set
auditory speech perception tests were lower than in the control group.
Both of these studies reported lower results than the present
study.19
Parents should be informed before surgery about the possible effects of
ear anomalies on auditory performance and language skills. However, a
comprehensive preoperative radiological examination, successful surgery,
and an individually tailored postoperative rehabilitation program should
be included.