Cochlear Reimplantation Research Articles

Cochlear reimplantation outcomes over 20 years: Expertise in reimplantation surgery and auditory-speech rehabilitation

ObjectivesThe aim of this study was to present an institution's experience with cochlear reimplantation (CRI), to assess surgical challenges and post-operative outcomes and to increase the success rate of CRI. Study designRetrospective single-institution study. SettingTertiary medical center. MethodsWe retrospectively evaluated data from 76 reimplantation cases treated in a tertiary center between 2001 and 2022. Clinical features including etiology of hearing loss, type of failure, surgical issues, and auditory speech performance were analyzed. Categorical Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores were used to evaluate pre- and post-CRI outcomes. ResultsThe CRI population comprises of 7 patients from our institute,69 referred patients from other centers. Device failure was the most common reason (68/76, 89.5 %) for CRI; in addition, there were 7 medical failures and 1 had both soft device failure. Medical failures included flap rupture and device extrusion, magnet migration, auditory neuropathy, leukoencephalopathy, foreign-body residue and meningitis. In 21/76 patients, the electrode technology was upgraded. The mean time to failure was 0.58–13 years, with a mean of 4.97 years. The mean (± SD) CAP and SIR scores before and after CRI were 5.2 ± 1.2 versus 5.5 ± 1.1 and 3.4 ± 1.1 versus 3.5 ± 1.1, respectively. Performance was poor in six patients with severe cochlear malformation, auditory nerve dysplasia, leukoencephalopathy, and epilepsy. ConclusionCRI surgery is a challenging but relatively safe procedure, and most reimplanted patients experience favorable postoperative outcomes. Medical complications and intracochlear damage are the main causes of poor postoperative results. Therefore, adequate preoperative preparation and atraumatic CRI should be carried out for optimal results.

Knowledge and Practice in Cochlear Re-Implantation in the UK: A Survey for Audiologists.

Cochlear implantation (CI) has proven to be a highly effective method for rehabilitating individuals with severe to profound hearing loss. However, challenges persist, particularly in cases where CI failure necessitates re-implantation. This study aims to address the gap in understanding the knowledge and practices of audiologists in the UK regarding cochlear re-implantation through a comprehensive questionnaire survey. A bespoke questionnaire was distributed to audiologists working with CI across the UK. The survey, which included multiple-choice items, open-text responses, and visual analogue scales, was made accessible via an online link shared through professional bodies, email groups, and social media platforms. The survey received 27 responses, predominantly from female audiologists (71.4%), with significant representation from London (28.6%) and the East of England (21.4%). A majority of respondents had over 16 years of CI experience (35.7%) and held a master's degree (60.7%). Key reasons for CI re-implantation included electrode failure (82.1%) and hermetic seal failure (60.7%). While respondents showed strong confidence in counselling (88.8%) and managing re-implanted devices (84.6%), there was a noted variation in opinions regarding the need for additional training in intraoperative measures. This survey highlights the current practices and training needs of UK audiologists in CI re-implantation. This underscores the importance of targeted training to fill knowledge gaps and improve clinical care during CI re-implantation, ultimately enhancing outcomes for both audiologists and CI recipients.

Speech perception in patients submitted to cochlear reimplantation

Speech perception in patients submitted to cochlear reimplantation

Speech perception in patients submitted to cochlear reimplantation.

To analyze the performance of auditory speech perception (PF) after cochlear implant (CI) replacement surgery and associations with age, times of use of the first CI, deprivation, recovery and use of the second device. The retrospective study analyzed the medical records of 68 participants reimplanted from 1990 to 2016, and evaluated with PF performance tests, considering as a reference, the greater auditory capacity identified during the use of the first CI. Also analyzed were: Etiology of hearing loss; the reasons for the reimplantation; device brands; age range; sex; affected ear; age at first implant; time of use of the first CI, deprivation, recovery and use of the second device. The analyzes followed with the Chi-Square and Spearman, Mann-Whitney and Kruskal-Wallis tests (CI=95%; p≤0.05; Software SPSS®.v22). Most were children with hearing loss due to idiopathic causes and meningitis. Abrupt stoppage of operation was the most common cause for device replacement. Most cases recovered and maintained or continued to progress in PF after reimplantation. Adults have the worst recovery capacity when compared to children and adolescents. The PF capacity showed a significant association (p≤0.05) with: age at first implant; time of use of the first and second CI. Periodic programming and replacement of the device when indicated are fundamental for the maintenance of auditory functions. Being young and having longer use of implants represent advantages for the development of speech perception skills.

Surgical issues and managements in cochlear reimplantation in 32 children

Objective:To summarize the clinical characteristics of children undergoing surgery of cochlear reimplantation, focus on various problems and management in cochlear reimplantation, in order to avoid related problems in surgery of cochlear reimplantation and the initial implantation. Methods:A total of 32 children who underwent cochlear reimplantation in Peking University Third Hospital from July 2018 to July 2022 were retrospectively analyzed, and the duration from the initial implantation was from 1 year to 8 years. The cochlear implant mapping was performed 4 weeks after the operation, and the auditory performance was evaluated. Results:Special intraoperative issues included 32 cases with bone and soft tissue hyperplasia at various sites（2 cases with obvious bone hyperplasia in cochlear window, 1 case with obvious bone hyperplasia in subperiosteal tunnel of wire）, 5 cases with bone defects in important structures（including the posterior wall of the external auditory canal, the facial nerve canal, and the subperiosteal pocker of the receiver-stimulator）, 1 case with cholesteatoma, 4 cases with other lesions or foreign bodies, 4 cases with abnormal position of the electrodes（migration or reversal）. All operations were successfully completed without complications. Postoperative recoveries were smooth. Conclusion:In the initial cochlear implantation, attention should be paid to retain residual hearing as much as possible, fully consider the possibility of postoperative bone hyperplasia, avoid large amounts of non-absorbable adhesive materials, avoid bone defects in important structures（such as facial nerve canal or posterior wall of the external auditory canal）, pay attention to the depth and orientation of electrode implantation. The possibility of "hidden injury" mentioned above should be fully considered in surgery of cochlear reimplantation to avoid new injury or complication.

Electrode array positioning after cochlear reimplantation from single manufacturer

Objective To investigate whether revision surgery with the same device results in a change in three key indicators of electrode positioning: scalar location, mean modiolar distance (), and angular insertion depth (AID). Methods Retrospective analysis of a cochlear implant database at a university-based tertiary medical center. Intra-operative CT scans were obtained after initial and revision implantation. Electrode array (EA) position was calculated using auto-segmentation techniques. Initial and revision scalar location, , and AID were compared. Results Mean change in for all ears was −0.07 mm (SD 0.24 mm; P = 0.16). The mean change in AID for all ears was −5° (SD 67°; P = 0.72). Three initial implantations with pre-curved EAs resulted in a translocation from Scala Tympani (ST) to Scala Vestibuli (SV). Two remained translocated after revision, while one was corrected when revised with a straight EA. An additional five translocations occurred after revision. Conclusions In this study examining revision cochlear implantation from a single manufacturer, we demonstrated no significant change in key indicators of EA positioning, even when revising with a different style of electrode. However, the revision EA is not necessarily confined by the initial trajectory and there may be an increased risk of translocation.

Analysis of aided thresholds in children who have undergone cochlear reimplantation: a ten-year follow-up.

To characterize hearing thresholds at frequencies of 500, 1000, 2000 and 4000 Hz in children undergoing reimplantation with a follow-up of at least 10 years. Retrospective review of medical records of children who underwent reimplantation surgery for at least 10 years. The auditory thresholds obtained in free-field pure tone audiometry with the cochlear implant were evaluated at frequencies of 500, 1000, 2000 and 4000 Hz at four different times: 1 (before failure), 2 (activation), 3 (five years after reimplantation) and 4 (ten years after reimplantation, regardless of the time of use of the 2nd CI) in patients with a follow-up of at least 10 years. Evaluating patients who underwent reimplantation, it was observed that the thresholds of 500, 1000, 2000, 4000 Hz were similar in the long term to those obtained in patients who were implanted only once, thus not presenting damage in the detection of sounds. Reimplantation had no long-term effect on the hearing thresholds obtained in children who underwent this surgery due to internal component failure.

Cochlear Reimplantation Rate and Cause: a 22-Year, Single-Center Experience, and a Meta-Analysis and Systematic Review.

In terms of cochlear reimplantation, there is no consensus on the definition, range, or calculation formulation for the reimplantation rate. This study aims to put forward a relatively standardized and more explicit definition based on a literature review, calculate the rate of cochlear reimplantation, and examine the classification and distribution of the reimplantation causes. A systematic review and retrospective study. A relatively clearer definition was used in this study: cochlear reimplantation is the implantation of new electrodes to reconstruct the auditory path, necessitated by the failure or abandonment of the initial implant. Seven English and Chinese databases were systematically searched for studies published before July 23, 2021 regarding patients who accepted cochlear reimplantation. Two researchers independently applied the inclusion and exclusion criteria to select studies and complete data extraction. As the effect size, the reimplantation rate was extracted and synthesized using a random-effects model, and subgroup and sensitivity analyses were performed to reduce heterogeneity. In addition, a retrospective study analyzed data on cochlear reimplantation in a tertiary hospital from April 1999 to August 2021. Kaplan-Meier survival analysis and the log-rank test were adopted to analyze the survival times of cochlear implants and compare them among different subgroups. A total of 144 articles were included, with 85,851 initial cochlear implantations and 4276 cochlear reimplantations. The pooled rate of cochlear reimplantation was 4.7% [95% CI (4.2% to 5.1%)] in 1989 to 2021, 6.8% [95% CI (4.5% to 9.2%)] before 2000, and 3.2% [95% CI (2.7% to 3.7%)] after 2000 ( P =0.003). Device failures accounted for the largest proportion of reimplantation (67.6% [95% CI (64.0% to 71.3%)], followed by medical reasons (28.9% [95% CI (25.7% to 32.0%)]). From April 1999 to August 2021, 1775 cochlear implants were performed in West China Hospital (1718 initial implantations and 57 reimplantations; reimplantation rate 3.3%). In total, 45 reimplantations (78.9%) were caused by device failure, 10 (17.5%) due to medical reasons, and 2 (3.5%) from unknown reasons. There was no difference in the survival time of implants between adults and children ( P = 0.558), while there existed a significant difference between patients receiving implants from different manufacturers ( P < 0.001). The cochlear reimplantation rate was relatively high, and more attention should be paid to formulating a standard definition, calculation formula, and effect assessment of cochlear reimplantation. It is necessary to establish a sound mechanism for long-term follow-up and rigorously conduct longitudinal cohort studies.

Audiological Outcomes and Associated Factors after Pediatric Cochlear Reimplantation.

Cochlear implants are the most common and successful sensory neuroprosthetic devices. However, reimplantation can be required for medical reasons, device failure, or technological upgrading. Resolving the problem driving the intervention and offering stable or better audiological results are the main challenges. We aimed to analyze the success rate of this intervention and to identify factors influencing speech perception recovery after reimplantation in the pediatric population. We retrospectively collected the causes and the outcomes of 67 consecutive reimplantations in one cochlear implant center over 30 years. Reimplantation resolved the cause without recurrence for 94% of patients. The etiology of deafness, time since implantation, indication of reimplantation, sex, and age did not influence word discrimination test scores in silence, 3 years after surgery. However, adherence to a speech rehabilitation program was statistically associated with gain in perception scores: +8.9% [−2.2; +31.0%] versus −19.0% [−47.5; −7.6%] if no or suboptimal rehabilitation was followed (p = 0.0037). Cochlear reimplantation in children is efficient and is associated with predictable improvement in speech perception, 3 years after intervention. However, good adherence to speech rehabilitation program is necessary and should be discussed with the patient and parents, especially for the indication of reimplantation for technological upgrading.

Research Status and Future Development of Cochlear Reimplantation.

Cochlear implants are the most successful sensory prostheses worldwide, and they can be useful for patients with severe and profound hearing impairment. However, various complications, including infection, pain, and device failure which is mainly due to falls and trauma, are associated with the use of cochlear implants. Reimplantation is required to replace the initial device in severe complications. Nevertheless, reimplantation can present certain surgical risks and may impose a significant economic and psychological burden on patients and their families; therefore, it requires greater attention and focus. This article presents a review of the literature on cochlear reimplantation and summarizes the current status, knowledge gaps, and future research directions on cochlear reimplantation. Since 1980s, cochlear reimplantation techniques can be considered to be relatively mature; however, some clinical and scientific problems remain unresolved, including the lack of a unified definition of cochlear reimplantation, non-standardized calculation of the reimplantation rat, and insufficient effect assessment. This review highlights the urgent need to establish an international consensus statement on cochlear reimplantation research to standardize the definition, calculation formulas of reimplantation rate, and follow-up systems.

Auditory performance after cochlear reimplantation

AimThe aim of this study was to evaluate the impact of cochlear reimplantation (CR) on hearing performance in children and adults with severe to profound hearing loss. Material and MethodsRetrospective observational study. ObjectivesThe main objective of this study was to determine whether there was a difference in hearing performance before and after CR. Secondary objectives were to analyze reasons for CR; to assess correlations between auditory performance and complete electrode reinsertion during CR, age, gender, explantation-to-CR interval, and interval between first implantation and CR; and to assess difference in APCEI score and the French evaluation protocol for implanted patients before and after CR. ResultsComparison of speech perception scores before and after explantation-reimplantation showed no significant difference (P>0.005) at 1 year or at 2 years after CR. In 80% of cases, reimplantation was due to hard implant failure. In other cases, it was undertaken for soft failure (diminished performance but no abnormalities on integrity testing) (8%), medical reasons (6%), or undetermined reasons (6%). There was no significant correlation between auditory performance at 1 or 2 years and complete or incomplete reinsertion of electrodes, age, gender, explantation-to-CR interval, or interval between first implantation and CR (P>0.005). For the adult subgroup, the French evaluation protocol scores did not differ after reimplantation (P=0.62). Likewise, for the child sub-group, APCEI and CAP results did not deteriorate after reimplantation. ConclusionReimplantation had no negative impact on hearing and speech perception, but provided performance equivalent to or better than after initial implantation.

Speech Audiometrical Results Before and After Reimplantation of Cochlear Implants

Objectives: This study aimed to compare the audiological outcomes of cochlear reimplantation with those of the first cochlear implant (CI). Design: A retrospective analysis was performed on the data of all CI recipients who received the first CI at the age of 8 years or above and who were subsequently reimplanted on the same side. All participants who received their first implant after January 1, 2000, and who were reimplanted before January 1, 2021, were included. CI recipients who were unable to perform an open-set of Flemish monosyllable speech audiometry were excluded. The participants’ clinical files were reviewed in terms of the cause of hearing loss, age at the first and second implantation, device types, the time between the first and second surgery, speech reception scores before and after reimplantation, and the reason for reimplantation. Results: Reimplantation was due to device failure in 19 out of 22 patients, performance decrement in two patients, and medical reasons in one patient. The interval between the first and second CI ranged from 8 to 218 mo. Within-subject analysis showed the speech reception performance with the second CI to be significantly better than that with the first CI at all follow-up time points, with average within-patient gains of 17%, 16%, 12%, and 15% at 3 mo, 9 mo, 3 years, and the highest scores achieved, respectively. After reimplantation, the performance was better than the last results before reimplantation, and this was significant from 9 mo after reimplantation onwards. Three patients (14%) had a performance degradation with the second CI, which was probably owing to (1) difficulties in reimplantation surgery leading to a reduced number of active channels, (2) insufficient experience with the second CI as the reimplantation has been performed recently, and (3) advanced fenestral and retrofenestral otosclerosis. Conclusions: The present study shows that speech reception performance after reimplantation yields faster and better results than the first implant. It takes a couple of months to get better results than those before the reimplantation. Only in a minority of participants, a small deterioration may be observed. It seems that soft failures in the absence of measurable technical abnormalities call for caution with regard to reimplantation.

Reference function of old electrical stimulation electrode in cochlear-reimplantation in children

ObjectivesTo explore the causes of cochlear implantation and reference function of old electrical stimulation electrode in cochlear reimplantation in children. MethodsThe causes, surgical methods and problems found during the operations of 24 cases of cochlear reimplantation in Henan Children's Hospital from June 2016 to April 2018 were analyzed. ResultsTwenty-three cases successfully completed the surgery of cochlear-reimplantation, and the remaining one case had approximately 1/3 of the anterior end of the residual cochlear electrode due to high resistance at the time of withdrawal of the electrodes. The causes of re-implantation were implant equipment failure (eleven cases), elevated impedance values of all electrodes after head trauma (two cases), and implant prolapse together with the electrode caused by a traffic accident (one case). ConclusionThe old stimulus electrode can provide an important reference to reduce the risk of operation and ensure the success of the reoperation.

Cochlear implant failures and reimplantation: A 30-year analysis and literature review.

The objectives of the study were to present an institutional experience with device failures and cochlear reimplantation rates over a 30-year period and to perform a detailed literature review. Retrospective institutional experience and literature review. A review of cochlear implant failures over a period of 30 years, between January 1988 and March 2017, at a single institution was conducted. Cochlear implant failures were calculated based on manufacturer, type of failure, and overall failure rate. Survival analysis was performed using Kaplan-Meier curves. An electronic search of the PubMed, Web of Science, and EMBASE databases revealed 24 articles on the topic of cochlear device failure. Data on reimplantation and device failure rates were extracted from this literature review and analyzed. A total of 804 cochlear implantations were reviewed from three manufacturers. The institutional reimplantation rate was 2.9% compared to the pooled rate of 6.0% calculated from the literature review. Medical failures accounted for 0.5% of the overall failures, device failures accounted for 1.6%, and inconclusive failures account for 0.7%. Survival analysis revealed a significant difference among manufacturers. An improved device failure rate was noted in the adult population (0.8%) as compared to the pediatric population (2.8%). This 30-year review represents one of the longest series in the literature examining reimplantation, device failure, and medical failure rates. Cochlear implant survival varied by manufacturer and was significantly better in adult compared to pediatric patients. NA Laryngoscope, 130:782-789, 2020.

A Retrospective Study of Cochlear Re-Implantations - Experience from a Large Centre in India.

Cochlear re-implantation (CRI) is becoming increasingly common throughout the world. However, studies regarding CRI incidence and etiology are lacking from developing countries like ours. The aim of this study was to present the Indian experience with CRI based on our experience. Objectives were to determine the incidence and the indications of CRI and the cumulative survival rate (CSR) of cochlear implantation (CI). Our study was a retrospective one, conducted at a tertiary care centre in southern India. 1,500 consecutive cochlear implanted ears from 1997 to 2016 were studied. All patients who underwent CRI during this period were included in the study. There were a total of 53 ears (31 male and 22 female ears) who underwent CRI. This gives an incidence of 3.53%. The most common indication of CRI was device failure in 39 ears contributing to 73.6% of the total CRI. The overall CSR of CI in pediatric population was 96.5% over a 20-year period. The CRI incidence and etiology at our centre appears to reflect the findings of the literature. Cochlear implant centres across the world should report the CSR of devices used at their respective centres so that it can be made an important criterion in choice of implant.

A Case in which Cochlear Reimplantation was Repeated Thrice due to Electrode Exposure and Cholesteatoma Formation

A Case in which Cochlear Reimplantation was Repeated Thrice due to Electrode Exposure and Cholesteatoma Formation

Prioritization of Reimplantation in Previously Successful Cochlear Implantation Following Natural Device Failure.

Cochlear reimplantation procedures account for approximately 5% of all implant cases and may be caused by internal device failure, skin flap complications, or an unexpected decline in auditory performance. This issue, in concert with changing demographics, expanded audiometric candidacy criteria, adult bilateral implantation, and implantation for unilateral hearing loss, all place escalating pressure on device availability and resource allocation in a publically funded health care system. The predictable and problematic access to a scare medical resource requires rigor in establishing program priority and formal policy. We present a single cochlear implant center's working reflections and an attempt at a principled approach to rationing health care decisions. Different approaches to health care rationing are examined and discussed. We describe a method of allocation that is currently employed by a large Canadian quaternary care center and ground this method in important principles of distributive justice as they apply to health care systems. We elect to recognize device failure as analogous to sudden sensorineural hearing loss, with the associated need to expedite reimplantation. We consider this an ethical approach grounded in the egalitarian principle of equality of opportunity within cohorts of patients. Porting the practice from sudden sensorineural hearing loss, the time-sensitive need for hearing restoration, and maximized communication outcomes, dictates prioritization for this patient population. The predicted evolution of health systems globally and the shape of future medical practice will be heavily influenced by both the macro and micro level resource-dependent decisions implant centers currently face.

Pediatric cochlear reimplantation: Decision-tree efficacy

ObjectivesThe context leading to pediatric cochlear reimplantation (CreI) can be complex. The objectives of this study were to define initial CreI indications, analyze final diagnosis and draw up a decision-tree. MethodsA retrospective study included patients undergoing CreI between 2005 and 2015. Demographic characteristics, CreI circumstances and technical reports were collected. Circumstances indicating CreI were classified in 3 groups: performance decrement, suspected device failure, or medical. After CreI, final diagnoses were classified in 2 groups: confirmed failure (DFail) or medical (DMed). Results69 out of 734 cochlear implantation surgeries were for CreI (8%). Manufacturers’ reports were available in 64 cases (93%). Two principal causes were found: trauma and infection. Initial indications were: performance decrement: 27%; device failure: 56%; and medical: 17%. Final diagnoses were: DFail: 72%; and DMed: 28%. Initial indication and final diagnosis were similar in 86% of cases. The majority of the 14% initial indication errors belonged to the “performance decrement” group. Traumatic causes correlated with risk of initial indication error (P=0.039). ConclusionApart from spontaneous device failure, the two causes of CreI were infection and trauma. Using the present decision algorithm, half of the complex cases were resolved after CreI.

Cochlear re-implantation: lessons learnt and the way ahead

Conclusion A cochlear re-implantation procedure is undesirable; however, the cochlear implant surgeon may have to perform a re-implantation procedure occasionally for various reasons. Following standard techniques, implant performance comparable with primary implantation may be achieved. Objective To study the causes and outcomes of cochlear re-implantation in an Asian Indian population. Study design Retrospective analysis of clinical charts over an 18-year period with prospective follow-up of patients. Methods The charts of 534 patients, who underwent cochlear implant, at an Otorhinolaryngology institutional Centre, from January 1997 to January 2015 were studied. Of these, the charts of 18 patients who underwent cochlear re-implantation were studied. The causes and audiological and speech outcomes were analysed. Results Eighteen patients (3.4%) underwent cochlear re-implantation for various reasons. The commonest indication was device failure in seven patients (39%), followed by electrode extrusion in five (28%), trauma in three (11%), electrode migration in two (11%) and improper electrode placement in one (6%) patient. The audiological performance tests and speech tests either remained the same or improved from those achieved for patients undergoing primary implantation, in 87% patients.

Surgical findings and auditory performance after cochlear implant revision surgery.

The objective of this study was to review cochlear reimplantation outcomes in the tertiary hospital and analyze whether facts such as type of failure, surgical findings, or etiology of deafness have an influence. A retrospective study including 38 patients who underwent cochlear implant revision surgery in a tertiary center is performed. Auditory outcomes (pure tone audiometry, % disyllabic words) along with etiology of deafness, type of complication, issues with insertion, and cochlear findings are included. Complication rate is 2.7 %. Technical failure rate is 57.9 % (50 % hard failure and 50 % soft failure), and medical failure (device infection or extrusion, migration, wound, or flap complication) is seen in 42.1 % of the cases. Management of cochlear implant complications and revision surgery is increasing due to a growing number of implantees. Cases that require explantation and reimplantation of the cochlear implant are safe procedures, where the depth of insertion and speech perception results are equal or higher in most cases. Nevertheless, there must be an increasing effort on using minimally traumatic electrode arrays and surgical techniques to improve currently obtained results.