Sequential Cochlear Implantation Research Articles

Cochlear implantation in patients with inner ear schwannomas: a systematic review and meta-analysis of audiological outcomes.

In patients with inner ear schwannomas (IES), reports on hearing rehabilitation with cochlear implants (CI) have increased over the past decade, most of which are case reports or small case series. The aim of this study is to systematically review the reported hearing results with CI in patients with IES considering thedifferent audiologic outcome measures used in different countries. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, a search of published literature was conducted. We included patients with IES (primary or with secondary extension from the internal auditory canal (IAC) to the inner ear, sporadic or NF2 related) undergoing cochlear implantation with or without tumour removal. The audiological results were divided into the categories "monosyllables", "disyllables", "multisyllabic words or numbers", and "sentences". Predefined audiological outcome measures were available from 110 patients and 111 ears in 27 reports. The mean recognition scores for monosyllabic words with CI were 55% (SD:24), for bisyllabic words 61% (SD:36), for multisyllabic words and numbers 87% (SD:25), and 71% (SD:30) for sentences. Results from for multisyllabic words and numbers in general showed a tendency towards a ceiling effect. Possible risk factors for performance below average were higher complexity tumours (inner ear plus IAC/CPA), NF2, CI without tumour removal ("CI through tumour"), and sequential cochlear implantation after tumour removal (staged surgery). Hearing loss in patients with inner ear schwannomas can be successfully rehabilitated with CI with above average speech performance in most cases. Cochlear implantation thus represents a valuable option for hearing rehabilitation also in patients with IES while at the same time maintaining the possibility of MRI follow-up. Further studies should investigate possible risk factors for poor performance. Audiological tests and outcome parameters should be reported in detail and ideally be harmonized to allow better comparison between languages.

Simultaneous versus Sequential Cochlear Implantation in Adults: Quantitative and Qualitative Outcomes.

To compare speech recognition and quality of life outcomes between bilateral sequentially and simultaneously implanted adult cochlear implant (CI) recipients who initially qualify for a CI in both ears. Retrospective chart review. Tertiary referral center. Retrospective chart review identified adults who underwent bilateral CI, either simultaneously or sequentially, at a high-volume center between 2012 and 2022. Sequentially implanted patients were only included if the second ear qualified for CI in quiet (defined as best-aided AzBio quiet testing <60%), at time of initial CI evaluation. Of 112 bilateral CI patients who qualified in both ears at initial evaluation, 95 underwent sequential implantation and 17 simultaneous. Age, duration, and etiology of hearing loss, and CI usage were similar between groups. Preoperatively, the sequential group had lower pure-tone average (PTA) in the 1st ear than the simultaneously implanted group (P = <.001) but, no difference in 2nd ear PTA (P = .657). Preoperative speech recognition scores were significantly higher for the sequential group; however, this was not true for postoperative scores. There was no difference in the proportion of patients showing significant CI-only or bilateral performance improvement between the groups. Both groups demonstrated similar benefit in quality of life measures. Our findings indicate both simultaneous and sequential cochlear implantation are effective in improving hearing performance and quality of life. Thus, bilateral versus simultaneous implantation should be discussed and tailored for each individual patient.

Late Bilateral Sequential Cochlear Implant and Quality of Life.

Introduction Hearing impairment is one of the main disorders that can interfere with the development of speech and language. In an individual, it can cause significant communication difficulties, social isolation, negative feelings, and depressive disorders. The hearing aids (HAs) and cochlear implant (CI) are options for profound and severe hearing loss, and the CI can be indicated for individuals who do not obtain benefits from HAs. Objective To evaluate the quality of life of individuals who underwent sequential bilateral CIs with a long surgical interval between procedures. Methods Fifteen patients, aged 8 to 70 years old, who underwent sequential bilateral CI, with an interval ≥ 4 years between surgeries, were evaluated. Quality of life was evaluated using three questionnaires: WHOQOL-BREF, SSQ-12 and HHIA in Portuguese. Results The WHOQOL-BREF questionnaire showed that the study participants had a good quality of life in all domains assessed. According to the SSQ-12, few reported inability to listen in communication situations. Most individuals were classified as having medium disability by the HHIA, but the social and emotional effects did not significantly affect the quality of life. Conclusion The use of questionnaires to assess the quality of life of patients with hearing impairment is a valuable tool to measure adaptation to CI. Patients undergoing bilateral sequential CI, even with a long interval between procedures, presented high indices of quality of life.

Novel Use of Depth Gauge to Keep Cochlear Lumen Patent in Bilateral Sequential Cochlear Implantation

Novel Use of Depth Gauge to Keep Cochlear Lumen Patent in Bilateral Sequential Cochlear Implantation

Bilateral sequential cochlear implantation in a patient with the CAPOS syndrome – postsynaptic auditory neuropathy related toa missense mutation within the ATP1A3 gene

ntroduction: This paper presents a boy with CAPOS syndrome (Cerebellar ataxia, Areflexia, Pes calvus, Optic atrophy, Sensorineural hearing loss) and postsynaptic auditory neuropathy who underwent bilateral, sequential cochlear implantation. Aim: The aim of the study is to describe the development of communication skills after bilateral cochlear implantation in a child with multiple disabilities including profound hearing loss and vision impairment. Material and methods: The patient’s medical history, including the results of diagnostic tests is presented. Sequential, bilateral cochlear implantation was performed at the age of 7 (right ear) and 8 years (left ear). Results: The results of audiometric tests confirmed postsynaptic auditory neuropathy. Molecular testing revealed a diseasecausing heterozygous c.3007C&gt;A variant in the ATP1A3 gene encoding the Na+/K+ ATPase. 14 months after surgery, the ability to speak had not been regained, but the patient was able to distinguish the environmental sounds. Conclusions: Cochlear implantation is recommended for patients with CAPOS syndrome. The development of communication skills improved the functioning of the child in the family and school environment. Meaning: The results observed in the presented patient differ from the results achieved by patients with cochlear hearing loss and presynaptic neuropathies, but indicate the validity of bilateral cochlear implantation in patients with postsynaptic neuropathy in the CAPOS syndrome.

Bilateral simultaneous cochlear implantation is a safe method of hearing rehabilitation in adults.

Bilateral cochlear implantation is an effective treatment for patients with bilateral profound hearing loss. In contrast to children, adults mostly choose a sequential surgery. This study addresses whether simultaneous bilateral CI is associated with higher rates of complications compared to sequential implantation. 169 bilateral CI surgeries were analyzed retrospectively. 34 of the patients were implanted simultaneously (group 1), whereas 135 patients were implanted sequentially (group 2). The duration of surgery, the incidence of minor and major complications and the duration of hospitalization of both groups were compared. In group 1, the total operating room time was significantly shorter. The incidences of minor and major surgical complications showed no statistically significant differences. A fatal non-surgical complication in group 1 was particularly extensively reappraised without evidence of a causal relationship to the chosen mode of care. The duration of hospitalization was 0.7days longer than in unilateral implantation but 2.8days shorter than the combined two hospital stays in group 2. In the synopsis of all considered complications and complication-relevant factors, equivalence of simultaneous and sequential cochlear implantation in adults in terms of safety was found. However, potential side effects related to longer surgical time in simultaneous surgery must be considered individually. Careful patient selection with special consideration to existing comorbidities and preoperative anesthesiologic evaluation is essential.

A longitudinal study of cortical auditory maturation and implications of the short inter-implant delay in children with bilateral sequential cochlear implants.

This longitudinal study aimed to investigate the maturational development of P1 latency and the effects of a short inter-implant delay in children who received bilateral sequential cochlear implants. Fourteen children (first CI mean age: 1.4±0.4 years and Second CI mean age: 3.3±0.5 years) who had received sequential bilateral cochlear implants during the sensitive period for auditory maturation participated in our study. The speech-evoked cortical P1 response was recorded after the activation of the second CI at four intervals (implant activation, 3 months, 6 months, 12 months) under three listening conditions (first CI, second CI, binaural). Our results showed that the P1 latencies of the second CI reached normative values within 3 months, but did not reach the P1 latency of the first CI until 12 months. We found a strong negative correlation between the inter-implant delay and the P1 latencies of the second CI when the second CI was activated. Changes in cortical auditory responses over time resulted in normal auditory maturation in children with sequential bilateral cochlear implants during the sensitive period. The results also provide evidence that the timing of auditory experience in the first ear during the sensitive period may influence the speed of compensation in children receiving sequential cochlear implants.

How Cochlear Implant Rehabilitation Impacts the Therapeutic Strategy for Vestibular Schwannoma

Since both surgery and more conservative treatments show long-term outcomes in patients with VS, the current challenge in its therapeutic strategy is to offer a cure with lower functional morbidity in terms of facial and hearing preservation or the possibility of hearing rehabilitation with a cochlear implant. PubMed and Scopus databases were searched from 2017 to November 2022. Fifteen articles met our selection criteria: (1) patients with a diagnosis of VS, either sporadic or NF2-related; (2) simultaneous or sequential cochlear implantation; (3) specified audiological test results and follow-up timing. Although the level of evidence for the presently included studies is low due to either the study design or the lack of treatment consensus, CI rehabilitation is a promising option, especially in small VS with compromised hearing and as a salvage option after a failed attempt at hearing preservation surgery.

Early activation of a late sequential cochlear implant systematic review

Early activation of Cochlear Implant (CI) is a technique where the processor is activated in less than 4 weeks. In this way, time and costs are reduced in the process of functional restoration of hearing. On the other hand, a late sequential cochlear implant is one where the second CI is implanted at a different surgical time than the first and the user's age is greater than 7 years. The aim of systematic review is to analyze the available information on the effects of early activation after late sequential cochlear implant surgery. Systematic literature search was performed, in databases, of studies about the effects of early activation of late sequential CI and early activation of CI in terms of quality of life, hearing and language from the years 2012 to June 2022. Fifteen publications were included in the clinical evidence review for early CI activation review, but no articles were found for review on the topic of early activation of late sequential CI. The review identified early CI activation as a safe and reliable procedure where the effects are positive on quality of life, hearing and speech by electrophysiological and auditory perceptual recordings. However, no information about the effects on early activation of late sequential CI is recognized. Keywords: early activation, cochlear implant, sequential, late, impedance, complications

Benefit of sequential bilateral cochlear implantation in children between 5 to 18 years old: A prospective cohort study.

To determine the benefit of sequential cochlear implantation after a long inter-implantation interval in children with bilateral deafness receiving their second implant between 5 and 18 years of age. Prospective cohort-study. Tertiary multicenter. 85 children with bilateral deafness and unilateral implantation receiving a contralateral cochlear implant at the age of 5 to 18 years. The primary outcomes were speech recognition in quiet and noise (CVC) scores. The secondary outcomes were language outcomes and subjective hearing abilities, all measured before and 12 months after sequential bilateral cochlear implantation. Medians of the paired data were compared using the Wilcoxon signed-rank test. Univariable linear regression analyses was used to analyze associations between variables and performance outcomes. A significant benefit was found for speech recognition in quiet (96% [89-98] vs 91% [85-96]; p < 0.01) and noise (65% [57-75] vs 54% [47-71]; p = 0.01) in the bilateral CI condition compared to unilateral (n = 75, excluded 10 non-users). No benefit was seen for language outcomes. The subjective sound quality score was statistically significant higher in bilateral compared to the unilateral CI condition. Pre-operative residual hearing level in the ear of the second implant, the inter-implant interval and age at time of second implantation was not significantly associated with performance scores. After 12 months of use, sequential bilateral cochlear implantation showed improved speech perception in quiet and noise and improved subjective sound quality outcomes in children despite a great inter-implantation interval (median of 8 years [range 1-16 years]).

Optimizing the Order of Sequential Cochlear Implantations

Optimizing the Order of Sequential Cochlear Implantations

Sustained reduction of tinnitus several years after sequential cochlear implantation

Objective This study aimed to explore the short- and long-term effects of a second cochlear implant (CI-2) on the reduction of tinnitus annoyance and tinnitus handicap. Design In a combined retrospective and prospective cohort study, tinnitus annoyance was measured before receiving the CI-2 (Pre), more than two years after (Post1) and more than seven years after (Post2), using the Tinnitus Handicap Inventory (THI), the Visual Analog Scale for the assessment of perceived tinnitus loudness (VAS-L) and annoyance (VAS-A), and a self-report questionnaire. Study sample Twenty sequentially bilaterally implanted adults with bothersome tinnitus. Results CI-2 implantation resulted in a statistically significant reduction of tinnitus handicap from severe at Pre to mild at Post1 (THI mean score reduced from 61.3 [SD = 19.4] to 29.3 [SD = 23.5]). The reduction in tinnitus annoyance was statistically significant from Pre to Post 2 (VAS-A reduced from 7.1 [SD = 1.5] to 3.4 [SD = 2.2]). The reduction in tinnitus loudness was not statistically significant. Conclusions The provision of a CI-2 for severely and profoundly hearing-impaired individuals with bothersome tinnitus is an effective method of providing long-term tinnitus relief.

Cochlear Implantation in the Setting of Menière's Disease After Labyrinthectomy: A Meta-Analysis.

Characterize the speech recognition and sound source localization of patients with unilateral Menière's disease who undergo labyrinthectomy for vertigo control with simultaneous or sequential cochlear implantation. PubMed, Embase, and Cochrane databases. The search was performed on May 6, 2020. The keywords utilized included: "Menière's disease AND cochlear implant;" "cochlear implant AND single sided deafness;" "cochlear implant AND vestibular;" and "labyrinthectomy AND cochlear implant." Manuscripts published in English with a publication date after 1995 that assessed adult subjects (≥18 years of age) were included for review. Subjects must have been diagnosed with Menière's disease unilaterally and underwent labyrinthectomy with simultaneous or sequential cochlear implantation. Reported outcomes with cochlear implant (CI) use included speech recognition as measured with the consonant-nucleus-consonant (CNC) word test and/or sound source localization reported in root-mean squared (RMS) error. The method of data collection and study type were recorded to assess level of evidence. Statistical analysis was performed with Wilcoxon signed ranks test. Data from 14 CI recipients met the criteria for inclusion. Word recognition comparisons between the preoperative interval and a postactivation interval demonstrated a significant improvement with the CI (p = 0.014), with an average improvement of 23% (range -16 to 50%). Sound source localization postoperatively with the CI demonstrated an average RMS error of 26° (SD 6.8, range 18.7-43.1°) compared to the 42° (SD 19.1, range 18-85°) in the preoperative or CI off condition, these two conditions were not statistically different (p = 0.148). Cochlear implantation and labyrinthectomy in adult patients with Menière's disease can support improvements in speech recognition and sound source localization for some CI users, though observed performance may be poorer than traditional CI candidates.

The impact of unilateral, simultaneous, or sequential cochlear implantation on pediatric language outcomes

Objectives The purpose of this study was to determine the impact of unilateral versus bilateral cochlear implantation on receptive and expressive spoken language outcomes. Secondary aims were to investigate factors timing of first and second implant placement and reliance on government funded health plans on language outcome. Methods This was a retrospective chart review of spoken language users with bilateral severe-to-profound hearing loss. A total of 204 children were included, 105 in the bilateral group and 99 in the unilateral group. Multiple regression analyses were completed to investigate factors that influence language outcomes at age 5. Results Recipients who received bilateral CIs performed significantly higher on measures of receptive and expressive language than those with unilateral implants. Discussion This study demonstrates that bilateral implantation has a significant impact on receptive and expressive aspects of language development, and should be strongly considered as standard practice for children with bilateral severe to profound hearing loss. Conclusion These results indicate that families should be counseled that language outcomes are better with bilateral cochlear implantation than unilateral implantation. Cochlear implant teams should continue to consider the impact of socioeconomic status on outcomes and explore new methods to reduce the impacts and barriers of poverty to language development.

Changes in electrically evoked auditory brainstem responses in children with sequential bilateral cochlear implants

ObjectivesThe primary aim of this study is to investigate whether the electrical stimulation of the second ear causes a difference in electrically evoked auditory brainstem responses (eABR) between two ears over time. MethodsThe study included thirteen subjects under the age of five who used cochlear implants for at least six months in the first ear prior to the sequential cochlear implantation. Postoperative eABRs were conducted on the 1st (first fitting of the second speech processor), 3rd, and 6th months of the second implantation in the basal, medial, and apical electrode positions. The recording was started with the second cochlear implant (CI2), and then the first cochlear implant (CI1) was tested. Sound field audiometry and receptive/expressive language assessments were also performed at 1 and 6 months after the second cochlear implantation. ResultseABR results indicate that when eV wave latencies are examined for all electrodes, CI2 is significantly longer than CI1 (p < 0.05). When eV wave amplitudes are examined for all electrodes, CI1 is significantly higher than the CI2 (p < 0.05). eV latency and amplitude changes between both implants were examined up to six months after implantation. Statistically significant changes were observed in the basal, medial, apical electrode for eV wave latencies, and only in the medial electrode for eV wave amplitudes (p < 0.05). Average sound field thresholds and receptive/expressive language scores improved statistically significantly for all subjects at the end of the study (p < 0.05). ConclusionThe postoperative eABR test is a valuable test battery that provides the clinician with important ideas about the estimated threshold, comfortable and audible sound level, CI performance, and auditory pathways up to the brainstem. Since the maturation is still ongoing, an extended period longer than six months is needed to evaluate interaural differences.

Sequential Bilateral Cochlear Implantation With Prolonged Time Intervals.

Purpose The aim of the study was to assess whether sequential cochlear implantation (CI) with a prolonged interimplant interval (M = 15.2 years) between the first and second CIs benefited speech recognition and health-related quality of life. Method This prospective study included 14 prelingually deafened participants who received their second CI after a prolonged interimplant interval (M = 15.2 years). Additionally, speech recognition ability over a 12-month period of bilateral implant use was investigated. The results of the speech recognition test in both quiet and noisy conditions were statistically analyzed for each CI alone and both CIs together. Nijmegen Cochlear Implant Questionnaire scores were also collected at activation and at 12 months after activation. Results Improvements in speech recognition ability were observed following the use of the first implant alone and with the use of both implants together; however, progress was much slower with the use of the second implant alone, following its introduction. Furthermore, a significant difference in the trajectory of speech recognition ability was observed between the first and the second implanted ear. According to Nijmegen Cochlear Implant Questionnaire scores, all participants benefitted from bilateral CI after 12 months. Conclusions Prolonged interimplant intervals resulted in asymmetrical speech recognition abilities. A significant improvement in the speech recognition scores was observed with the first implanted ear, and much slower progress was observed with the second implanted ear. However, the "poorer" second implanted ear could provide a considerable beneficial effect on the improved speech recognition and health-related quality of life with the bilateral CI. Supplemental Material https://doi.org/10.23641/asha.12861152.

Evolution of Cochlear implant mapping and vestibular function in a pediatric case of Labyrinthitis

BackgroundVestibular symptoms such as vertigo and imbalance are known to occur in some cochlear implant patients during the immediate postoperative period; however, acute vertigo in implanted children occurring remotely from the postoperative period has not been previously well-described.Case presentationA three-year-old girl with a history of bilateral sequential cochlear implantation presented with acute labyrinthitis associated with sudden onset of vertigo, balance impairment, and decline in right cochlear implant function 2 years after her most recent implant surgery. We describe her audiological and vestibular testing results during both the acute phase and following medical management and recovery.ConclusionAcute labyrinthitis should be considered when sudden onset vertigo and/or imbalance presents in children with cochlear implants outside of the perioperative period. Such symptoms should prompt early assessment of cochlear implant function, so that the device can be reprogrammed accordingly.

Electrically evoked ABR during cochlear implantation and postoperative development of speech and hearing abilities in infants with common cavity deformity as a type of inner ear malformation

Background: The electrically evoked auditory brainstem response (eABR) during cochlear implantation in common cavity (CC) deformity has not been clinically well studied.Aim/Objective: To investigate the eABR wave configuration during cochlear implantation, the postoperative development of hearing, and educational settings in infants with CC deformity.Materials and Methods: Nine infants who were congenitally deaf and found to have CC deformity and suspected cochlear nerve deficiency by temporal bone CT and MRI were studied. All of them underwent sequential and unilateral cochlear implantation and their eABRs were recorded during the surgery. The postoperative development was followed up.Results: eABRs of all the nine infants with CC deformity showed that the mean peak of the evoked wave V (eV) was the same as that in controls at latencies but was twofold higher than that in controls at thresholds and their postoperative hearing thresholds improved markedly.Conclusion and Significance: The brainstem auditory pathways of the infants were considered intact on the basis of the eV peak latencies in the eABRs. The postoperative development of their speech and hearing abilities and their educational settings varied, probably because of the twofold higher thresholds of their eABRs and limited number of auditory neural units.

Critical Factors for Binaural Hearing in Children with Bilateral Sequential Cochlear Implantation: First Implant Performance and Inter-Implant Interval

Objectives: This study evaluated the influence of the performance of the first cochlear implant (CI-1) on the second implant (CI-2) and the significance of inter-implant intervals in children with sequential cochlear implantation. Method: Thirty-four patients were included for speech perception outcome and 38 patients were included for subjective hearing satisfaction in daily life in this study. The patients were classified into 3 groups according to inter-implant interval: group I, <4 years; group II, 4–7 years; group III, >7 years. Open-set speech perception scores before and at 3, 6, 12, and 24 months after the second implantation was compared among the CI-1, CI-2, and bilateral CI conditions. Subjective hearing benefits in daily life were measured using a questionnaire of Speech, Spatial, and Qualities of Hearing Scale (SSQ) for parents of children with impaired hearing, and device use and preference were evaluated (by phone interview.) Results: The speech perception of children using the CI-2 only improved quickly within 3 months postoperatively and were similar to those using the CI-1 only. The results of monosyllabic and disyllabic word tests using CI-2 at 3 months after second implantation were not significantly different from those in patients using the CI-1 only. In the sentence test, the scores using the CI-2 only were not significantly different from those using the first implant only at 6 months after second implantation. SSQ scores were similar among groups and the worst score in each section was shown from the questions about performance under noisy conditions in each section. Device usage habits showed that 17 (44.7%) and 16 (42.1%) patients preferred bilateral and the CI-1, respectively. Only 5 (13.2%) patients wanted the CI-2 rather than the CI-1. While group I and II showed a prominent positive attitude to bilateral use, group III, for which the inter-implant interval was 7 years or more, showed a definite preference for the CI-1 (p < 0.01). Conclusions: Functional binaural benefits were achieved in patients who were good performers with the CI-1 after the second implantation irrespective of the inter-implant interval. Sequential CI should be strongly recommended for patients with unilateral CI showing a good performance.

Predicting sequential bilateral cochlear implantation performance in postlingually deafened adults; A retrospective cohort study.

To identify which preoperative patient characteristics influence sequential bilateral cochlear implantation performance and to create a statistical model that predicts benefit. Multicentre retrospective cohort study. All patients were operated in four academic teaching hospitals in Perth, Australia, and followed up by audiologists of the Ear Science Institute Australia. A total of 92 postlingually deafened adult patients who had undergone sequential cochlear implantations between 19 June 1990 and 14 March 2016 were included. Patients were excluded if the 12-month follow-up consonant-nucleus-consonant (CNC) phoneme score was missing. The effect of 18 preoperative factors on the CNC phoneme score in quiet (at 65 dB SPL) with the second cochlear implant (CI2) one year after implantation. Two factors were positively correlated to speech understanding with CI2: Wearing a hearing aid (HA) before receiving CI2 (r = 0.46, P = 0.00) and the maximum CNC phoneme score with the first CI (CI1) (r = 0.21, P = 0.05). Two factors were negatively correlated: the length of hearing loss before CI2 in the second implanted ear (r = -0.25, P = 0.02) and preoperative pure tone average (PTA) (0.5, 1, 2 kHz) before CI2 in the second implanted ear (r = -0.27, P = 0.01). The following model could be created: predicted CNC phoneme score with CI2 (%) = 16 + (44 * HA use before CI2 (yes)) - (0.22 * length of hearing loss before CI2 (years)) + (0.23 * CNC phoneme score with CI1 (%)). Because the effect of HA use before implantation played such a major role, we also created a model after exclusion of the HA factor: Predicted CNC phoneme score with CI2 (%) = 82 - (0.17 * length of hearing loss before CI2 (years)) - (0.27 * PTA in second implanted ear before CI2 (0.5, 1, 2 kHz)) + (0.20 * CNC phoneme score with CI1 (%)). Advanced age or a long interval between implantations does not necessarily lead to poor CI2 results. Patients who are successful HA users before CI2, who have a low PTA before CI2, a high CNC phoneme score with CI1 and a limited length of hearing loss before CI2, are likely to be successful CI2 recipients.