Underwent Cochlear Implant Surgery Research Articles

Influence of Cochlear Anatomy on Intraoperative Electrically Evoked Compound Action Potentials.

Objective: The electrically evoked compound action potential (ECAP) is an objective measure to indirectly assess spiral ganglion neurons. The ECAP provides inputs about the prognoses of cochlear implant (CI) recipients. Several factors such as cochlear morphology can affect ECAP measurements. This study aims to investigate the variation effect of cochlear parameters on intraoperative ECAP thresholds. Methods: This is a retrospective study on patients who underwent CI surgery with normal inner ear morphology at our center between 2017 and 2023. Cochlear anatomical parameters, including diameter (A value), width (B value), and height (H value), as well as cochlear duct length (CDL), were measured pre-operatively using OTOPLAN software (Version 3.0). Cochlear implant intraoperative objective measures were also collected. The correlation between the cochlear parameters and intraoperative objective measures was studied. Results: A total of 45 patients underwent cochlear implantation. The mean age was 2.4 ± 0.9 years. The mean CDL and cochlear coverage values were 33.2 ± 2.0 mm and 76.0 ± 5.7%, respectively. The ECAP threshold increased toward basal electrodes, with ECAP values as follows: apical 13.1 ± 3.8; middle 14.3 ± 3.7; and basal 15.6 ± 4.8. Additionally, the A, B, and H values showed a positive correlation with ECAP thresholds in different cochlear regions. The B value showed a significant moderate correlation with ECAP thresholds in the middle and basal electrodes but not in the apical electrodes. Conclusions: Cochlear anatomical parameters correlate with intraoperative ECAP thresholds. The B value showed a significant association with ECAP thresholds in the middle and basal electrodes. These findings could delineate the impact of the B value in CI and optimize electrode selection. Further research is required to study this correlation and its impact on postoperative outcomes.

The Inter-Phase Gap Offset Effect as a Measure of Neural Health in Cochlear Implant Users With Residual Acoustic Hearing.

The inter-phase gap (IPG) offset effect is defined as the dB offset between the linear parts of electrically evoked compound action potential (ECAP) amplitude growth functions for two stimuli differing only in IPG. The method was recently suggested to represent neural health in cochlear implant (CI) users while being unaffected by CI electrode impedances. Hereby, a larger IPG offset effect should reflect better neural health. The aims of the present study were to (1) examine whether the IPG offset effect negatively correlates with the ECAP threshold and the preoperative pure-tone average (PTA) in CI recipients with residual acoustic hearing and (2) investigate the dependency of the IPG offset effect on hair cell survival and intracochlear electrode impedances. Seventeen adult study participants with residual acoustic hearing at 500 Hz undergoing CI surgery at the University Hospital of Zurich were prospectively enrolled. ECAP thresholds, IPG offset effects, electrocochleography (ECochG) responses to 500 Hz tone bursts, and monopolar electrical impedances were obtained at an apical, middle, and basal electrode set during and between 4 and 12 weeks after CI surgery. Pure-tone audiometry was conducted within 3 weeks before surgery and approximately 6 weeks after surgery. Linear mixed regression analyses and t tests were performed to assess relationships between (changes in) ECAP threshold, IPG offset, impedance, PTA, and ECochG amplitude. The IPG offset effect positively correlated with the ECAP threshold in intraoperative recordings (p < 0.001) and did not significantly correlate with the preoperative PTA (p = 0.999). The IPG offset showed a postoperative decrease for electrode sets that showed an ECochG amplitude drop. This IPG offset decrease was significantly larger than for electrode sets that showed no ECochG amplitude decrease, t(17) = 2.76, p = 0.014. Linear mixed regression analysis showed no systematic effect of electrode impedance changes on the IPG offset effect (p = 0.263) but suggested a participant-dependent effect of electrode impedance on IPG offset. The present study results did not reveal the expected relationships between the IPG offset effect and ECAP threshold values or between the IPG offset effect and preoperative acoustic hearing. Changes in electrode impedance did not exhibit a direct impact on the IPG offset effect, although this impact might be individualized among CI recipients. Overall, our findings suggest that the interpretation and application of the IPG offset effect in clinical settings should be approached with caution considering its complex relationships with other cochlear and neural health metrics.

Dizziness after cochlear implantation: Is the age an independent risk factor?

Abstract Background: Hearing loss and imbalance are the prevalent chronic conditions in the elderly, significantly impacting their quality of life (QoL). The relationship between otologic surgery, particularly cochlear implant (CI) procedures, and postoperative dizziness remains a critical area of investigation. Understanding this relationship is essential, especially given the rising number of older adults undergoing CI surgery. Materials and Methods: This retrospective, observational study, conducted between January 2016 and August 2021, assessed the influence of age on chronic dizziness following CI surgery. Sixty adults with postlingual sensorineural hearing loss who underwent unilateral CI surgery were evaluated. Comprehensive preoperative and postoperative assessments included the Dizziness Handicap Inventory (DHI) and QoL measures. Results: The study found a significant improvement in speech perception postimplantation, regardless of the age at surgery. However, postoperative dizziness, as measured by the DHI, increased significantly compared to preoperative levels. This increase in dizziness was not correlated with the age at implantation but was strongly associated with preexisting dizziness. Conclusions: These findings emphasize the need for thorough preoperative evaluations and patient counseling, particularly for those with preexisting balance disturbances, to optimize the outcomes and manage expectations regarding postoperative dizziness. This study contributes to the understanding of dizziness post-CI in older adults, highlighting the importance of considering individual patient conditions in the management of CI recipients.

Evaluation of the outcomes of cochlear implant in children with auditory neuropathy

Objective: To investigate the auditory and speech abilities of children with congenital auditory neuropathy (AN) after cochlear implant (CI), and to analyze the role of genetic testing in predicting the postoperative outcomes of CI in AN patients. Methods: Fourteen children diagnosed with AN by audiological battery test and underwent CI surgery in Xijing Hospital of the Air Force Medical University from 2002 to 2021 were included in this study (9 males and 5 females), with an implantation age of (3.1±1.7) years (mean±standard deviation, the same as follows). The preoperative audiological results and deafness gene results were analyzed. Another 52 children with ordinary sensorineural hearing loss (SNHL) were selected as the control group (30 males and 22 females), with an implantation age of (2.2±0.9) years. The demographic factors such as age and gender were matched with those of the AN group. The modified Category Auditory Performance (CAP-Ⅱ) and Speech Intelligence Rate (SIR) were used to evaluate the development of postoperative auditory and speech abilities in two groups. The Mandarin Speech Test System was used to test the speech recognition rate of monosyllabic and disyllabic words and sentences. Matlab 2022 software was used to analyze the data. Results: The results of gene in 14 children with AN showed that 6 cases had OTOF gene mutations, 2 cases (siblings) were confirmed to have TNN gene mutations through whole exome sequencing, and the remaining 6 cases were not find any clear pathogenic gene mutations. All subjects underwent CI surgery with electrodes implanted into the cochlea smoothly, and there were no postoperative complications. After surgery, all AN children had improved auditory and speech abilities, but only 64% (9/14) of AN children with CI had auditory ability scores comparable to the control group of SNHL children (including 2 children with TNN gene mutations), and 36% (5/14) of AN children had lower scores than the control group of SNHL children.The average speech recognition rate of two children with TNN gene mutations was 86.5%, and of two children with OTOF gene mutations was 83.2%. Conclusions: AN children achieved varying degrees of auditory and speech abilities after CI, but the postoperative effects varied greatly. Some children achieved similar results as ordinary SNHL children, but there were still some children whose effects were worse than those of ordinary SNHL children. The postoperative efficacy of CI in two children with AN caused by TNN pathogenic genes were comparable to that of ordinary SNHL in children. Genetic testing had certain reference value for predicting the postoperative effect of CI in AN children.

Differences in music appreciation between bilateral and single-sided cochlear implant recipients

ObjectiveTo compare changes in music appreciation after cochlear implant (CI) surgery for patients with bilateral and single-sided deafness (SSD). MethodsA retrospective cohort study was performed on all adult CI unilateral or bilateral recipients from November 2019 to March 2023. Musical questionnaire subset data from the Cochlear Implant Quality of Life (CIQOL) – 35 Profile Instrument Score (maximum raw score of 15) was collected. Functional CI assessment was measured with CI-alone speech-in-quiet (SIQ) scores (AzBio and CNC). Results22 adults underwent CI surgery for SSD and 21 adults for bilateral deafness (8 sequentially implanted). Every patient group had clinically significant improvements (p < 0.001) in mean SIQ scores in the most recently implanted ear (Azbio (% correct) SSD: 14.23 to 68.48, bilateral: 24.54 to 82.23, sequential: 6.25 to 82.57). SSD adults on average had higher music QOL scores at baseline (SSD: 11.05; bilateral: 7.86, p < 0.001). No group had significant increases in raw score at the first post-operative visit (SSD: 11.45, p = 0.86; bilateral: 8.15, p = 0.15). By the most recent post-implantation evaluation (median 12.8 months for SSD, 12.3 months for bilateral), SSD adults had a significant increase in raw score from baseline (11.05 to 12.45, p = 0.03), whereas bilaterally deafened (7.86 to 9.38, p = 0.12) adults had nonsignificant increases. ConclusionsSSD patients demonstrate higher baseline music appreciation than bilaterally deafened individuals regardless of unilateral or bilateral implantation and are more likely to demonstrate continued improvement in subjective music appreciation at last follow-up even when speech perception outcomes are similar.

Long-Term Cochlear Implant Sound Processor Usage in Children with Single-Sided Deafness.

To assess cochlear implant (CI) sound processor usage over time in children with single-sided deafness (SSD) and identify factors influencing device use. Retrospective, chart review study. Pediatric tertiary referral center. Children with SSD who received CI between 2014 and 2020. Primary outcome was average daily CI sound processor usage over follow-up. Fifteen children with SSD who underwent CI surgery were categorized based on age of diagnosis and surgery timing. Over an average of 4.3-year follow-up, patients averaged 4.6 hours/day of CI usage. Declining usage trends were noted over time, with the first 2 years postactivation showing higher rates. No significant usage differences emerged based on age, surgery timing, or hearing loss etiology. Long-term usage decline necessitates further research into barriers and enablers for continued CI use in pediatric SSD cases.

Why Do Cochlear Implant Candidates Defer Surgery? A Retrospective Case-Control Study.

Despite undergoing thorough cochlear implant (CI) candidacy evaluation and counseling, some patients ultimately elect against implantation. This study sought to identify patient-related and socioeconomic factors predicting CI deferral. A retrospective study of adult (≥18 years old) CI candidates presenting between 2007 and 2021 at a tertiary academic CI center was performed. The primary outcome was device implantation. Data collected included age, gender, hearing status, race, zip code of residence, median family income (MFI), distance traveled from the CI center, marital status, employment status, and insurance status. Multivariable binary logistic regression was performed to identify predictors of implantation. A total of 200 patients qualifying for CI were included, encompassing 77 adults deferring surgery (CI-deferred) and 123 consecutive adults electing for surgery (CI-pursued). Age, gender, hearing status, insurance type, employment status, distance from the implant center, and MFI were comparable between the groups (p > 0.05). Compared to CI-pursued patients, CI-deferred patients were more likely to be non-Caucasian (24.7% vs. 9.8%, p = 0.015) and unmarried (55.8% vs. 38.2%, p = 0.015). On multivariable logistic regression, older age (OR 0.981, 0.964-0.998, p = 0.027), African American race (OR 0.227, 0.071-0.726, p = 0.012), and unmarried status (OR 0.505, 0.273-0.935, p = 0.030) were independent predictors of implant deferral. This study demonstrates that increasing age at evaluation, African American race, and unmarried status are predictors for deferring CI surgery despite being implant candidates. These patients may benefit from increased outreach in the form of counseling, education, and social support prior to undergoing CI surgery. 3 - retrospective study with internal control group Laryngoscope, 134:2857-2863, 2024.

Influence of depressive disorders, stress, and personality traits on quality of life after cochlear implantation

PurposeThis study aimed to determine whether preoperative depressiveness, stress, and personality influence quality of life (QOL) after cochlear implant (CI) surgery.MethodsIn this prospective study, 79 patients undergoing CI surgery were evaluated preoperatively and 12 months postoperatively. Disease-specific QOL was assessed with the Nijmegen Cochlear Implant Questionnaire (NCIQ) and general QOL with the WHOQOL-BREF. Depressiveness and stress were assessed with the Patient Health Questionnaire (PHQ-D). The Charlson Comorbidity Index (CCI) was used to classify comorbidities. The Big Five Personality Test (B5T) was used to assess the basic personality dimensions. Speech comprehension was evaluated in quiet with the Freiburg monosyllable test and in noise with the Oldenburg sentence test.ResultsAfter CI surgery, the total NCIQ score improved significantly (Δ 17.1 ± 14.7, p < 0.001). General QOL (WHOQOL-BREF, Δ 0.4 ± 9.9, p = 0.357), stress (Δ 0.25 ± 3.21, p = 0.486), and depressiveness (Δ 0.52 ± 3.21, p = 0.121) were unaffected by CI surgery. Patients without elevated depressiveness (p < 0.01) or stress (p < 0.001) had significantly better total NCIQ scores. The results of the multiple regression analyses show that, after adjusting for the CCI, personality, age, and mental health stress (ß = − 0.495, p < 0.001) was significantly associated with postoperative NCIQ outcome scores. Depressiveness and neuroticism had the strongest influence on the generic QOL (ß = − 0.286 and ß = − 0.277, p < 0.05).ConclusionStress symptoms and personality traits are significant predictive factors for disease-specific QOL, as well as hearing status. This should be considered in the preoperative consultation and in optimizing the rehabilitation process.

Revision cochlear implant surgery in adults and children is a safe and effective technique: a retrospective single faculty study in Okayama University Hospital, Japan

Background Cochlear implant (CI) surgery is a safe surgical technique, although some patients require revision CI surgery. Aims/Objectives This study investigated the cause and underlying reason of revision CI surgery as well as hearing outcomes in a single institution. Patients and Methods This retrospective study evaluated patients who underwent CI surgery between April 2006 to March 2022 (n = 351). Sex, aetiology of hearing loss (HL), age and period from initial CI surgery to reimplantation, cause of revision, and related factors were examined. Results Twelve patients (8 males, 4 females) received CI reimplantation. The revision surgery rate was 2.59% (3.15% children, 1.69% adults); the period from initial surgery to reoperation was 8.60 ± 6.56 years for 9 children with congenital HL and 15.27 ± 5.72 years for 3 adults with progressive HL. Device failure was the most common cause (n = 8), followed by infections (n = 2), advanced facial irritation symptoms (n = 1), and electrode slip-out (n = 1). Mean preoperative and postoperative CI thresholds were 44.0 ± 9.46 dBnHL and 39.19 ± 8.89 dBnHL (p < .068), respectively. Conclusion and Significance Caregiver education, surgical technique advances, flap design, and extensive antibiotic use may decrease the revision surgery rate. The lack of post-revision deterioration of the hearing threshold contributed to well-being in patients with CI.

Blinded comparison of computed tomography, ultrasound and needle methods to measure skin flap thickness for cochlear implantation

Purpose Patient suitability for cochlear implant (CI) devices compatible with magnetic resonance imaging and CI processor configuration is dependent on their retro-auricular skin flap thickness. This is typically measured intra-operatively using a needle and therefore patients are not guaranteed their implant of choice prior to surgery. We aimed to identify an accurate method to measure skin flap thickness pre-operatively to streamline CI selection and simplify the consent process. Methods Blinded prospective skin flap thickness measurements for patients undergoing CI surgery were recorded using pre-operative computed tomography (CT) and ultrasound (US), and intraoperative needle measurement. Results Fifty-six adult patients (36 females, 20 males; mean age 59 years) were included. The mean flap thickness was measured highest by CT (6.9 mm, 95% CI 6.5–7.3 mm), followed by US (6.3 mm, 95% CI 5.9–6.7 mm) and lastly needle (5.5 mm, 95% CI 5.1–5.9 mm) (p < 0.0001). A strong positive correlation (p < 0.001) was noted between all three modalities: CT vs needle (r = 0.869), US vs needle (r = 0.865), and CT vs US (r = 0.849). Conclusion Accurate, non-invasive measurement of skin flap thickness prior to CI surgery can be achieved using CT or US. We recommend the routine use of US in the outpatient clinic to minimise unnecessary radiation exposure.

USE OF THE NUCLEUS SMARTNAV® SYSTEM IN INTRAOPERATIVE TELEMETRY OF COCHLEAR IMPLANT

Tests performed intraoperatively are routine tools in cochlear implant (CI) programs worldwide. Recently, Cochlear™ launched the Nucleus Smartnav® system that describes new parameters measured during insertion of the electrode array into the cochlea, verifies its position, tests impedance and AutoNRT. Objective: To describe the use of the Cochlear™ Nucleus SmartNav® system as an intraoperative measurement tool in cochlear implant surgery. Material and Methods: Patient with bilateral and congenital profound prelingual deafness. He has been using an individual sound amplification device (PSAD) bilaterally since childhood, has reasonable speaking skills and good understanding of others’ speech. Although IC was previously indicated, he chose to keep the hearing aid. However, given the inefficient gain, mainly in the left ear, a bimodal adaptation was suggested: CI in the left ear and hearing aids in the right. At the age of 48, he underwent CI surgery on the left, using the Cochlear™ CI622 model with CP1001 speech processor and intraoperative measurements performed by the Nucleus® SmartNav system. The impedance test and NRT were also performed intraoperatively using the Nucleus® SmartNav system, after reviewing the insertion of the electrodes. Result: The measurements obtained during the insertion of the electrode array in the cochlea allowed greater intraoperative control by enabling fine adjustments in the surgical technique. Conclusion: The Nucleus Smartnav® system endorses technologies that aim to increase surgical precision and reduce complications.

Cochlear implantation programming characteristics and outcomes of cochlear nerve deficiency.

Due to the specificity of cochlear implantation (CI) programming parameters and outcomes in cochlear nerve deficiency (CND) patients, this study aimed to investigate the correlation between programming parameters and outcomes and further compare the difference between normal and CND groups. Ninety (95 ears) CND patients (normal cochlea, 39; malformed cochlea, 56) and seventy-nine (81 ears) normal cochlea patients who underwent CI surgery with either Med-El or Cochlear devices were included. The programming parameters and outcomes evaluated by the questionnaires were collected and compared among the normal CND, malformed CND, and normal groups in the two device groups, and their correlation was analyzed. In the CND group, a reduced stimulation rate, higher pulse width, and triphasic pulse were needed in some cases. The stimulus levels of the CND group were significantly higher than that of the normal group (p < 0.05), but the outcomes of the CND group were significantly worse than that of the normal group (p < 0.05), and the stimulus level was significantly correlated with the outcomes (p < 0.05). However, there was no difference between normal and malformed CND groups. The non-auditory response was observed in the CND group, especially the ones with malformations. The CI programming parameters of some CND patients need to be adjusted, and a slower stimulation rate and higher pulse width are required sometimes. CND patients need a higher stimulus level than normal patients but their outcomes are poorer. Non-auditory response should be noticed in CND patients during programming.

Cochlear implantation in single-sided deafness: a single-center experience of 138 cases.

Assess the outcomes in patients who underwent cochlear implant (CI) for single-sided deafness (SSD). All patients affected by SSD who underwent CI at Gruppo Otologico, Piacenza, from October 2012 to May 2022 with at least 6months of follow-up were selected in the study group. The analysis included subjective and objective measures performed pre-operative and up to 24months after surgery. Hearing threshold on both sides was evaluated with a weighted four-frequency average (PTA [0.5kHz + 1kHz + 2kHz + 4kHz]/4) on pure tone audiometry and speech audiometry (Speech Discrimination Score, SDS). The Speech Spatial and Qualities of Hearing scale (SSQ Questionnaire) for binaural hearing benefits and sound localization, the Tinnitus Handicap Inventory Questionnaire (THI) and Dizziness Handicap Inventory Questionnaire (DHI) were used for subjective assessment. Data from 138 patients, 69 males and 69 females, (mean age 49years, range 17-77years) underwent CI for SSD were examined. Single-sided hearing deprivation average before undergoing CI surgery was 2.5years (range 3months-35years). There was a significant reduction of THI and DHI scores compared to pre-operative scores alongside a referred improvement in social, physical, and emotional well-being through the SSQ questionnaire. To the best of our knowledge, this paper descried the largest cohort of SSD who underwent CI in a single institution. According to our findings CI in patients affected by SSD represents a valuable tool for an overall improvement of tinnitus and dizziness but also quality of life, after at least 6months of follow-up. Further studies are desirable to improve rehabilitation pathways and possibly set new standards of care of this condition.

Cochlear implantation surgery with conscious sedation in the very elderly: a feasibility study comparing cochlear implant outcomes in general anaesthesia (GA) and local anaesthesia (LA) cohorts

Background: To characterize outcomes of very elderly patients who have had cochlear implant (CI) surgery under awake conditions with local anaesthesia (LA)/conscious sedation with patients who underwent CI surgery under general anaesthesia (GA), as a preliminary feasibility study prior to a more detailed investigation.

Distance and Socieoeconomic Status as Barriers to Cochlear Implantation.

To assess the distance burden for access to cochlear implant (CI)-related services and to assess whether socioeconomic disadvantage or level of education and occupation influenced uptake of CIs. Retrospective case review. A CI services provider operating across multiple centers. All patients undergoing CI surgery in a 2-year period between March 2018 and February 2020. Diagnosis of hearing loss, CI surgery, and subsequent habilitation and mapping. Distance traveled by patients to their audiological diagnostic, CI surgery hospital, and habilitation sites; subjects' index of relative socioeconomic advantage and disadvantage (IRSAD) and index of education and occupation (IEO). n = 201 children and n = 623 adults. There was a significant difference across IRSAD domains for children (p < 0.0001) and adults (p < 0.0001), and IEO in children (p = 0.015) and adults (p < 0.0001) when tested for equal proportions. The median driving distance from home to the diagnostic audiological site for children was 20 km (mean, 69 km; range, 1-1184 km; upper quartile, 79 km; lower quartile, 8 km). There was no significant difference between the driving distances from home to the CI surgery hospital site, or the mapping/habilitation sites between children and adults. There was no correlation for age at first surgery and either IRSAD/IEO. The burden of distance for access to CI in Australia is significant for the upper quartile who may not live within the large city centers. Greater consideration needs to be given regarding barriers to CI for those in lower socioeconomic and educational groups to ensure equity of access across different socioeconomic and educational level backgrounds.

Institutional Analysis of the Surgical Outcomes of Cochlear Implantation in Deprived Population.

Cochlear implantation (CI) surgeries are safe and performed successfully in many patients; however, postoperative complications still occur, which may be influenced by socioeconomic and demographic variables. Methodology: This is a retrospective observational study of 146 adults and children with hearing loss, who had CI surgery between 2017 and 2022. This study aims to assess the frequency and nature of surgical complications in patients from a low socioeconomic background who underwent CIsurgery in different geographic areas. For the analysis of data, IBM SPSS Statistics for Windows, Version 21.0 (Released 2012; IBM Corp., Armonk, New York, United States) was used. A total of 146 candidates were evaluated, out of which 82 were male (56.16%) and 64 (43.84%) were female. The age of patients at the time of surgery ranged from 1-50 years. All of the patients underwent unilateral CI. Eighteen implanted patients developed minor complications with an incidence rate of 12.31%. There were no major complications observed. Further, we did not observe any post-operative meningitis as our study group was vaccinated against pneumococcal and meningococcal diseases and Haemophilus influenzae type B (Hib). CI is an effective and safe surgical procedure for the treatment and rehabilitation of people who are deaf. It is possible to avoid complications by using meticulous surgical methods and regular post-operative monitoring to identify and treat any issues as soon as possible, regardless of socioeconomic status.

A 3-Year Follow-Up and Radiological Analysis of Cochlear Implantation Patients with Cochlear Nerve Deficiency and Modiolar Deficiency-Type Malformations.

Cochlear nerve deficiency (CND) is often combined with modiolar deficiency-type inner ear malformations, which cause variable cochlear implantation (CI) outcomes. We aimed to assess the postoperative development of auditory and speech perception in CND patients with modiolar deficiency-type malformations after 3 years of follow-up to determine the factors correlated with CI outcomes. Sixty-seven CND patients with modiolar deficiency-type malformations who underwent CI surgery were retrospectively reviewed. Modiolar deficiency-type malformations included common cavity (CC), cochlear hypoplasia (CH) (including CH-I and CH-II) and incomplete partition-I (IP-I). Categorical auditory performance (CAP) and the infant-toddler meaningful auditory integration scale (MAIS) were used to assess auditory ability. The speech intelligibility rating (SIR) and meaningful use of speech scale (MUSS) were used to assess the speech intelligibility of these CI patients. The CI outcomes were evaluated at 0, 12, 24 and 36 months after implant activation. All patients demonstrated improvements in auditory ability and speech intelligibility after CI. There were no significant differences in CI outcomes at any time point according to the malformation type. The number of nerve bundles within the internal auditory canal (IAC) showed significant differences at 12, 24 and 36 months after CI ( p < 0.05). Patients with one nerve bundle had relatively poor CI outcomes. CND patients with modiolar deficiency-type malformations showed continuous improvement in auditory and speech abilities after CI. Compared with malformations, the number of nerve bundles should be given more attention when selecting the side for CI.

The Outcome of Cochlear Implantations in Deaf-Blind Patients: A Multicenter Observational Study.

This multicenter study aimed to evaluate the auditory and speech outcomes of cochlear implantation (CI) in deaf-blind patients compared with deaf-only patients. Retrospective cohort study. Multiple cochlear implant centers. The current study was conducted on 17 prelingual deaf-blind children and 12 postlingual deaf-blind adults who underwent CI surgery. As a control group, 17 prelingual deaf children and 12 postlingual deaf adults were selected. Cochlear implantation. Auditory and linguistic performances in children were assessed using the categories of auditory performance (CAP) and Speech Intelligibility Rating (SIR) scales, respectively. The word recognition score (WRS) was also used to measure speech perception ability in adults. The mean CAP, SIR, and WRS cores were compared between the deaf-only and deaf-blind groups before CI surgery and at "12 months" and "24 months" after device activation. Cohen's d was used for effect size estimation. We found no significant differences in the mean CAP and SIR scores between the deaf-blind and deaf-only children before the CI surgery. For both groups, SIR and CAP scores improved with increasing time after the device activation. The mean CAP scores in the deaf-only children were either equivalent or slightly higher than those of the deaf-blind children at "12 months post-CI" (3.94 ± 0.74 vs 3.24 ± 1.25; mean difference score, 0.706) and "24 months post-CI" (6.01 ± 0.79 vs 5.47 ± 1.06; mean difference score, 0.529) time intervals, but these differences were not statistically significant. The SIR scores in deaf-only implanted children were, on average, 0.870 scores greater than the deaf-blind children at "12 months post-CI" (2.94 ± 0.55 vs 2.07 ± 1.4; p = 0.01, d = 0.97) and, on average, 1.067 scores greater than deaf-blind children at "24 months post-CI" (4.35 ± 0.49 vs 3.29 ± 1.20; p = 0.002; d = 1.15) time intervals. We also found an improvement in WRS scores from the "preimplantation" to the "12-month post-CI" and "24-month post-CI" time intervals in both groups. Pairwise comparisons indicated that the mean WRS in the deaf-only adults was, on average, 10.61% better than deaf-blind implanted adults at "12 months post-CI" (62.33 ± 9.09% vs 51.71 ± 10.73%, p = 0.034, d = 1.06) and, on average, 15.81% better than deaf-blind adults at "24-months post-CI" (72.67 ± 8.66% vs 56.8 ± 9.78%, p = 0.002, d = 1.61) follow-ups. Cochlear implantation is a beneficial method for the rehabilitation of deaf-blind patients. Both deaf-blind and deaf-only implanted children revealed similar auditory performances. However, speech perception ability in deaf-blind patients was slightly lower than the deaf-only patients in both children and adults.

Assessment of the correlation between residual hearing and audiologic outcomes after cochlear implantation in patients with cochlear nerve deficiency.

ObjectiveThis study aimed to assess the correlation between residual hearing and audiologic outcomes after cochlear implant (CI) surgery in patients with cochlear nerve deficiency (CND).MethodsThis retrospective study included 57 patients with CND who underwent CI surgery. Patients were divided into four groups according to hearing level (80–95, 95–110, 110–120, and >120 dB) and three groups according to residual hearing (entire spectrum hearing, partial spectrum hearing, and no spectrum hearing) based on the measured response at each frequency. Auditory performance (categorical auditory performance [CAP], Infant–Toddler Meaningful Auditory Integration Scale [IT‐MAIS]) and speech perception (speech intelligibility rating [SIR] and meaningful use of speech scale [MUSS]) were assessed before and 2 years after the surgery.ResultsForty‐seven (82.5%) patients had complete or total hearing loss (≥95 dB) and 17 (29.8%) had no spectrum hearing before CI surgery. Twenty‐nine (50.9%) patients did not exhibit residual hearing at 4 kHz. All patients demonstrated an improvement in auditory performance and speech perception: the CAP score in the 80–95 dB group was significantly higher than that in the 110–120 and >120 dB groups, and the entire spectrum hearing group showed significantly higher CAP, SIR, and IT‐MAIS scores than the partial spectrum hearing group and significantly higher CAP, SIR, IT‐MAIS, and MUSS scores than the no spectrum hearing group.ConclusionFor patients with CND, residual hearing, especially high‐frequency residual hearing, was poor and postoperative audiologic outcomes were significantly associated with the range of residual hearing.Level of Evidence4

Machine Learning-Based Prediction of the Outcomes of Cochlear Implantation in Patients With Cochlear Nerve Deficiency and Normal Cochlea: A 2-Year Follow-Up of 70 Children.

Cochlear nerve deficiency (CND) is often associated with variable outcomes of cochlear implantation (CI). We assessed previous investigations aiming to identify the main factors that determine CI outcomes, which would enable us to develop predictive models. Seventy patients with CND and normal cochlea who underwent CI surgery were retrospectively examined. First, using a data-driven approach, we collected demographic information, radiographic measurements, audiological findings, and audition and speech assessments. Next, CI outcomes were evaluated based on the scores obtained after 2 years of CI from the Categories of Auditory Performance index, Speech Intelligibility Rating, Infant/Toddler Meaningful Auditory Integration Scale or Meaningful Auditory Integration Scale, and Meaningful Use of Speech Scale. Then, we measured and averaged the audiological and radiographic characteristics of the patients to form feature vectors, adopting a multivariate feature selection method, called stability selection, to select the features that were consistent within a certain range of model parameters. Stability selection analysis identified two out of six characteristics, namely the vestibulocochlear nerve (VCN) area and the number of nerve bundles, which played an important role in predicting the hearing and speech rehabilitation results of CND patients. Finally, we used a parameter-optimized support vector machine (SVM) as a classifier to study the postoperative hearing and speech rehabilitation of the patients. For hearing rehabilitation, the accuracy rate was 71% for both the SVM classification and the area under the curve (AUC), whereas for speech rehabilitation, the accuracy rate for SVM classification and AUC was 93% and 94%, respectively. Our results identified that a greater number of nerve bundles and a larger VCN area were associated with better CI outcomes. The number of nerve bundles and VCN area can predict CI outcomes in patients with CND. These findings can help surgeons in selecting the side for CI and provide reasonable expectations for the outcomes of CI surgery.