Effect of congenital inner ear malformations (IEMs) on electrically evoked compound action potential (ECAP) responses in cochlear implant children.

PURPOSE: The study was designed to assess the electrically evoked compound action potential (ECAP) responses in children with inner ear malformations compared to children with normal inner ear anatomy. METHODS: The study included 235 prelingual deaf children who were implanted in cochlear implant unit in King Fahad University hospital-Imam Abdulrahman Bin Faisel University. Subjects were using either Cochlear Nucleus or Medel cochlear implant devices. We had 171 (64.5%) subjects with normal inner ear anatomy and 94 (35.5%) subjects with inner ear malformations (IEMs) and they were classified into 6 groups according to inner ear anatomy. Fourteen subjects (14.9%) subjects had enlarged vestibular aqueduct (EVA), 30 (32%) subjects had Mondini deformity, 25 (26.6%) subjects had incomplete partition type two (IPII), 9 (9.6%) subjects had incomplete partition type one (IPI) and 16 (17%) subjects had hypoplastic cochlea type III or IV. Intraoperative electrically evoked compound action potential (ECAP) responses were analyzed and compared in all subjects. RESULTS AND CONCLUSIONS: Measurable ECAP responses can be elicited in patients with IEMs in most of the channels. Severe malformations can affect the prevalence of measuring ECAP and getting identifiable waveform morphology. Additionally, increased thresholds and lower slope of AGF was observed in IEMs specially in more severe malformations (e.g. IPI). IPI patients with better word recognition scores tended to show more identifiable ECAP measurements. This could suggest the presence of some correlation between ECAP responses and patients' performance after cochlear implantation.

The Difficulties Encountered by Pediatric Cochlear Implant Patients and Their Parents during the COVID-19 Pandemic.

INTRODUCTION: The daily escalation in incidence and mortality caused by Coronavirus disease (COVID-19) has mandated forced curfew in our country (same as many other countries) to limit the spread of infection. This is predicted to have a more negative impact on cochlear implant (CI) patients since this group of patients needs a unique type of psychological, medical, and technical care in addition to a daily rehabilitation program. METHODS: A cross-sectional study based on Arabic questionnaire that looked into the collateral consequences of COVID-19 on the pediatric CI patients. The questionnaire was designed to highlight different problems such as exposure to head trauma or ear infection, difficulties in device maintenance and getting spare parts, impacts of the delay of programing or switch on appointments, and the impacts of missing rehabilitation sessions. Different ways of management of these problems are presented and discussed. RESULTS: A total of 174 parents responded to the questionnaire. The main problem met by the patients was missing their device programing and rehabilitation sessions. Many children had device maintenance and spare parts problems. Virtual clinics were helpful in solving different problems. Additionally, children who needed device programing were scheduled for remote programing sessions. CONCLUSION: Although the inevitable consequences of the COVID-19 pandemic are catastrophic, they are forcing the medical field to explore new opportunities by sitting up an infrastructure for future usage of telemedicine. Telemedicine is cost-effective and more convenient and enables health-care providers to be immune to future circumstances.

Voice acoustic characteristics of children with late-onset cochlear implantation: Correlation to auditory performance.

OBJECTIVES: To study the voice acoustic parameters of congenitally deaf children with delayed access to sounds due to late-onset cochlear implantation and to correlate their voice characteristics with their auditory performance. METHODS: The study included 84 children: a control group consisting of 50 children with normal hearing and normal speech development; and a study group consisting of 34 paediatric cochlear implant (CI) recipients who had suffered profound hearing loss since birth. According to speech recognition scores and pure-tone thresholds, the study group was further subdivided into two subgroups: 24 children with excellent auditory performance and 10 children with fair auditory performance. The mean age at the time of implantation was 3.6 years for excellent auditory performance group and 3.2 years for fair auditory performance group. Voice acoustic analysis was conducted on all study participants. RESULTS: Analysis of voice acoustic parameters revealed a statistically significant delay in both study groups in comparison to the control group. However, there was no statistically significant difference between the two study groups. DISCUSSION: Interestingly, in both excellent and fair performance study groups, the gap in comparison to normal hearing children was still present. While late-implanted children performed better on segmental perception (e.g. word recognition), suprasegmental perception (e.g. as demonstrated by objective acoustic voice analysis) did not progress to the same extent. CONCLUSION: On the suprasegmental speech performance level, objective acoustic voice measurements demonstrated a significant delay in the suprasegmental speech performance of children with late-onset CI, even those with excellent auditory performance.

Electrically evoked compound action potential (ECAP) in cochlear implant children: Changes in auditory nerve response in first year of cochlear implant use.

AIM: Recording of the electrically evoked compound action potential (ECAP) of the auditory nerve in cochlear implant (CI) patients represents an option to assess changes in auditory nerve responses and the interaction between the electrode bundle and the neural tissue over time. The aim of the present work is to assess ECAP changes during the first year of cochlear implant for the purpose of predicting thresholds and adjustment of the patients' programs over time. METHOD: Data were collected from 25 children using Cochlear Nucleus 24 implants. ECAP thresholds were examined at the time of surgery, at initial stimulation, and 3, 6 and 12 months post-stimulation. Five electrodes located at basal, middle, and apical positions in the cochlea were tested at each time interval and ECAP thresholds were analyzed and compared. RESULTS: There was a significant decrease in ECAP thresholds between the intraoperative measure and fitting time at all electrode sites. Mean ECAP thresholds measured at 3, 6 and 12 months post-stimulation remained similar to initial stimulation levels. Although there was no significant difference in ECAP thresholds recorded at fitting time and 12 months follow up session, there was significant increase in behavioral T and C levels from initial stimulation to the 12 months' time point. CONCLUSION: Most electrodes undergo non-significant change in ECAP thresholds over time, and therefore thresholds obtained on the day of initial stimulation can be used to estimate the patients' map levels at any time. On the other hand, intraoperative thresholds demonstrated significant change relative to postoperative recording times, limiting the ability to use intraoperatively recorded ECAP thresholds to predict postoperative measurements.

Effect of cochlear implant electrode array design on auditory nerve and behavioral response in children.

AIM: To study the effect of change in the array design of cochlear implant electrode on electrophysiological, and behavioral functional measures of cochlear implant users. METHOD: A total of 33 children using cochlear implants were included in this study. Subjects were implanted with different electrode types including Slim Straight (CI422) and Freedom Contour Advance (CI24RE) electrode arrays. The electrically evoked compound action potential (ECAP) thresholds were evoked by stimulation of basal, mid, and apical electrodes. The behavioral aided responses using the implant were obtained about 6-12 months post fitting of implant. RESULTS: ECAP thresholds decreased significantly postoperatively in both electrode arrays. Slim straight electrode (CI422) had higher thresholds than Freedom Contour Advance (CI24RE) electrode at most recording sites, but the differences were only significant at basal site. This is a direct consequence of a perimodiolar electrode versus a lateral wall electrode, i.e., the neurons are further away requiring more current (higher threshold) to record the NRT. CONCLUSION: Although the curved electrode array appeared to evoke responses at lower thresholds, effect on patient performance was not obvious.

Cortical auditory evoked potential (P1): a potential objective indicator for auditory rehabilitation outcome.

OBJECTIVE: Cortical auditory evoked potentials are a non-invasive tool that can provide objective information on maturation of the auditory pathways. This work was designed to study the role of cortical auditory evoked potential (P1) in assessment of the benefits of amplification and aural rehabilitation in hearing impaired children. DESIGN: The study consisted of 31 children classified into 2 groups. Study group included 18 hearing impaired children ranging in age 4-14 years old and classified into two subgroups according to adequacy of aural rehabilitation. A control group consisted of 13 normal hearing children ranging in age from 5 to 13 years. All children were subjected to history taking, basic audiological evaluation, intelligence quotient and language assessment. Cortical auditory evoked potential (P1) was measured using synthesized speech syllable /da/ as a recording stimulus that was presented binaurally via a loudspeaker. RESULTS: P1 was recorded in all children with significantly prolonged latencies in hearing impaired children with inadequate rehabilitation. P1 latency was correlated to hearing loss duration in hearing impaired children with inadequate aural rehabilitation. Auditory experience was correlated with P1 latency in hearing impaired children with adequate aural rehabilitation. CONCLUSION: Cortical auditory evoked potential (P1) might provide a clinical tool to monitor aural rehabilitation outcome and to guide intervention choices.