Pediatric cochlear implant revision surgery and reimplantation: an analysis of 957 cases

Cochlear Implant Revisions Over Three Decades of Experience

IMPORTANCE

The indications, technology, and surgical technique for cochlear implantation have evolved over the last three decades. Understanding the risk of cochlear implant revision (CIR) is important for patient counseling.

OBJECTIVE

The objective of this study was to analyze the rates, indications, and audiologic outcomes for CIR over three decades of experience at a single academic medical center.

DESIGN

A retrospective chart review was performed at a single academic medical center for individuals who underwent cochlear implantation between 1985 and 2022.

SETTING

Single academic medical center.

PARTICIPANTS

Three thousand twenty-five individuals who underwent 3,934 cochlear implant operations from 1985 to 2022.

EXPOSURE

Cochlear implantation.

MAIN OUTCOMES AND MEASURES

Rates, indications, risk factors, and audiologic outcomes for CIR.

RESULTS

There were 276 cases of CIR after primary implantation and an overall revision rate of 7.6% (95% confidence interval, 6.8-8.5%) over 37 years of follow-up with many cases of CIR secondary to Advanced Bionics vendor B and field action failure groups. CIR rates increased sharply through the early and mid-2000s and have since remained stable. Hard or soft device failure was the most common indication for CIR, accounting for 73% of cases. Pediatric patient status and previous CIR were associated with an increased risk of CIR. Audiologic outcomes after CIR were similar to those before device failure.

CONCLUSIONS AND RELEVANCE

CIR remains a common procedure most often performed for device failure. Pediatric patients and those who have undergone previous CIR are at the highest risk for future CIR. Audiologic outcomes remain stable after CIR, and these data will help providers counsel patients at the risk of future CIR and understand the risk factors associated with CIR.

Comparison of Adult and Pediatric Cochlear Implant Wound Complications: A Meta-Analysis

OBJECTIVE

To compare age-related differences in wound complications following cochlear implantation (CI).

METHODS

We performed a systematic review of PubMed, Cochrane Database, and Web of Science databases to identify original research evaluating the patient-level factors (demographics and medical history) associated with wound complications following CI. Outcomes were expressed as relative risk (RR) with 95% confidence intervals using the inverse variance method. Studies without comparison groups were described qualitatively.

RESULTS

Thirty-eight studies representing 21,838 cochlear implantations were included. The rate of wound complications ranges from 0% to 22%. Patient age (adult versus pediatric) was the only factor with comparison groups appropriate for meta-analysis. The 10 studies (n = 9547 CI's) included in the meta-analysis demonstrated that adults had a higher incidence of overall wound complications (2.94%) than in children (2.44%) (RR 1.31, 95% CI 1.01-1.69). Adults had a higher incidence of general/unclassified wound complications (2.07%) than in children (1.34%) (RR 1.68, 95% CI 1.12-2.52). There was no difference between adults and children for specific complications such as hematoma, infection, or seroma. Elderly patients (over age 75) have wound complication rates that range from 1% to 4%. No studies contained comparison groups regarding other patient-level factors and CI wound complications.

CONCLUSION

CI wound complication rates reported in the literature are low; however, adults have a higher risk of these complications than pediatric patients. The reported complication rate in elderly adults is low. There is a gap in CI research in consistently reporting wound complications and rigorous research investigating the impact of patient-level factors and wound complications.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:218-226, 2023.

Revision cochlear implant surgery for clinical reasons

Objective

To report the authors' experience in a series of patients treated with cochlear implant (CI) revision surgery due to medical problems.

Methods

Revision CI surgeries performed in a tertiary referral centre for medical reasons not related to skin conditions were reviewed; patients were included if device removal was required.

Results

17 cochlear implant patients were reviewed. The main reasons requiring revision surgery with device removal were: retraction pocket/iatrogenic cholesteatoma (6/17), chronic otitis (3/17), extrusion in previous canal wall down procedures (2/17) or in previous subtotal petrosectomy (2/17), misplacement/partial array insertion (2/17) and residual petrous bone cholesteatoma (2/17). In all cases surgery was performed through a subtotal petrosectomy. Cochlear fibrosis/ossification of the basal turn was found in 5 cases and uncovered mastoid portion of the facial nerve in 3 patients. The only complication was an abdominal seroma. A positive difference was observed between the number of active electrodes and comfort levels before and after revision surgery.

Conclusions

In CI revision surgeries performed for medical reasons, subtotal petrosectomy offers invaluable advantages and should be considered as first choice during surgical planning.

Misplaced Cochlear Implant Electrodes Outside the Cochlea: A Literature Review and Presentation of Radiological and Electrophysiological Findings

HYPOTHESIS

It is possible to detect when misplacement and malposition of the cochlear implant (CI) electrode array has occurred intraoperatively through different investigations. We aim to explore the literature surrounding cochlear implant misplacements and share our personal experience with such cases to formulate a quick-reference guide that may be able to help cochlear implant teams detect misplacements early.

BACKGROUND

Misplacement and malposition of a cochlear implant array can lead to poor hearing outcomes. Where misplacements go undetected during the primary surgery, patients may undergo further surgery to replace the implant array into the correct intracochlear position.

METHODS

Systematic literature review on cochlear implant misplacements and malpositions and a retrospective review of our program's cases in over 6,000 CI procedures.

RESULTS

Twenty-nine cases of CI misplacements are reported in the English literature. Sixteen cases of cochlear implant misplacements are reported from our institution with a rate of 0.28%. A further 12 cases of intracochlear malpositions are presented. The electrophysiological (CI electrically evoked auditory brainstem response, transimpedance matrix) and radiological (X-ray and computed tomography scan) findings from our experience are displayed in a tabulated quick-reference guide to show the possible characteristics of misplaced and malpositioned cochlear implant electrode arrays.

CONCLUSION

Both intraoperative electrophysiological and radiological tests can show when the array has been misplaced or if there is an intracochlear malposition, to prompt timely intra-operative reinsertion to yield better outcomes for patients.

Pain at the Cochlear Implant Site Requiring Device Removal in Pediatric Patients

OBJECTIVES

Idiopathic pain at the cochlear implant (CI) site outside of the immediate postoperative period is an uncommon occurrence but may necessitate device explantation. Our objective was to describe the clinical course for pediatric patients with CI site pain who ultimately required device explantation.

STUDY DESIGN

Retrospective chart review.

METHODS

We performed a retrospective database review of CIs performed at a tertiary referral center for pediatric cochlear implantation. We specifically evaluated pediatric patients who presented with pain at or near the CI device site and ultimately required explantation.

RESULTS

Fifteen patients (16 CIs) had pain at or near the CI site requiring device explantation. Cultures taken during site exploration or device explantation identified bacteria in 86% and 81% of procedures, respectively. Propionibacterium acnes and Staphylococcus non-aureus were the most commonly identified organisms.

CONCLUSIONS

The majority of patients with idiopathic pain in this cohort ultimately requiring CI explantation had chronic bacterial colonization.

LEVEL OF EVIDENCE

Level 4 (Case series) Laryngoscope, 2022.

Auditory performance after cochlear reimplantation

AIM

The 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 METHODS

Retrospective observational study.

OBJECTIVES

The 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.

RESULTS

Comparison 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.

CONCLUSION

Reimplantation had no negative impact on hearing and speech perception, but provided performance equivalent to or better than after initial implantation.

Cochlear implant failure: diagnosis and treatment of soft failures

Objective

Early diagnosis of cochlear implant failures (CIF) is a critical part of post-implantation follow-up. Diagnosis is challenging and time consuming. Our study aimed to describe diagnoses of CIF with emphasis on soft failures (SF), focusing on symptoms, time from symptoms to replacement, and differences between SF and hard failures (HF).

Methods

A retrospective review of medical records in a tertiary care referral paediatric medical centre including all patients who experienced CIF during 2000-2020.

Results

Of 1004 CI surgeries, 72 (7.2%) cases of CIF were included, of which 60 CIF were in children (mean age 3.1 years). Twenty-five cases were due to HF, 26 SF, and 21 due to medical reasons. Patients with SF were more likely to present with headache, dizziness, or tinnitus compared with those with HF. Facial stimulation and disconnections were more common in implants from Advanced Bionics, dizziness and tinnitus in Cochlear, and poor progression in Med-El. Mean time from symptoms to implant replacement surgery was longer in cases with SF compared to HF.

Conclusions

SF poses a diagnostic challenge. Symptoms such as headache, dizziness, and tinnitus are common. Diagnosis of failure should often be based on assessments of the implant and rehabilitation teams.

Surgical Factors Influencing Wound Complication After Cochlear Implantation: A Systematic Review and Meta-Analysis

OBJECTIVE

To identify perioperative surgical factors associated with wound complications following cochlear implantation (CI).

DATA SOURCES

PubMed, Web of Science, and Cochrane databases.

STUDY SELECTION

Eligible studies included peer-reviewed research in English evaluating wound complications (wound infection, skin flap breakdown/dehiscence, seroma/hematoma) following CI. Studies with paired samples were included in the meta-analysis.

DATA EXTRACTION

Surgical factors (techniques and perioperative management) in CI and reported wound complications were examined. Level of evidence was assessed using the Oxford Centre for Evidence-based Medicine guidelines and bias was assessed using the NIH Quality Assessment Tool.

DATA SYNTHESIS

Twenty-six studies representing 10,214 cochlear implantations were included. The overall wound complications rate was 3.1% (range 0.03-13.9%). Eleven studies contained paired data and were used for meta-analysis regarding three different surgical factors: incision length, implant placement method, and antibiotic usage. Longer incision lengths (≥7 cm) demonstrated a higher risk of wound complications (risk ratio 2.27, p = 0.02, CI 1.16-4.43). Different implant placement techniques (suture fixation versus periosteal pocket) (p = 0.08, CI 0.92-3.69) and postoperative antibiotic regimens (postoperative use versus none) (p = 0.68, CI = 0.28-7.18) were not associated with differences in wound complication rates following CI.

CONCLUSIONS

Overall rate of wound complications following CI is low. Shorter incision length is associated with lower risk of wound complications. Differences in perioperative techniques and practices regarding implant placement and antibiotic use were not associated with differences in wound complication rates. Considering the low number and quality of studies, there is a need for research in CI outcomes using paired sample prospective designs and standardized reporting.

Cochlear Implant Failure in the Pediatric Population

BACKGROUND AND OBJECTIVES

In cochlear implant (CI) surgery, the results and causes of revision and reimplantation may guide surgeons in establishing surgical protocols for revision surgery with safe audiological outcomes. The aim of this study was to review our experience in terms of etiology, surgical strategy, and hearing outcomes in pediatric patients who underwent CI removal and reimplantation.

SUBJECTS AND PURPOSE

All patients received implants of the same brand. Pre and postoperative Categories of Auditory Performance score and aided free-field pure tone audiometry thresholds were noted. In vivo integrity tests were performed for each patient and the results of ex vivo tests of each implant were obtained from manufacturer.

RESULTS

A total of 149 CIs were placed in 121 patients aged <18 years. The revision rate in children was 6.7% (10/121 children). Six patients had a history of head injury leading to a hard failure. The causes of reimplantation in others were soft failure (n=1), electrode migration (n=1), infection (n=1), and other (n=1). All patients showed better or similar postreimplantation audiological performance compared with pre-reimplantation results.

CONCLUSIONS

It is very important to provide a safe school and home environment and educate the family for reducing reimplantation due to trauma. Especially for active children, psychiatric consultation should be continued postoperatively.

Evaluating Reasons for Revision Surgery and Device Failure Rates in Patients Who Underwent Cochlear Implantation Surgery

Importance

Understanding the reasons for cochlear implant (CI) revision surgery and device failure rates is important for clinicians when counseling patients who are considering CI.

Objectives

To analyze the revision surgery rate, reasons for revision surgery, and device failure and survival rates of different device models in recipients of CIs.

Design, Setting, and Participants

In this cohort study, cochlear implants at Samsung Medical Center, a tertiary referral center, were retrospectively reviewed. Patients who underwent CI surgery from October 2001 to March 2019 were included. In the device survival analysis, the first revision surgery was considered the primary event, and the end point of observation was June 1, 2019.

Interventions

Therapeutic and rehabilitative CI surgery.

Main Outcomes and Measures

The revision surgery rate, reasons for revision surgery, and the failure and survival rates of different device models were analyzed. The Kaplan-Meier method and the log-rank test were used to present both the device survival and cumulative survival curves with rates.

Results

In this study, 43 of 925 patients with CIs (4.6%) underwent a revision surgery. Device failure was the most common reason (28 of 43 patients [65%]). Flap-associated problems and migration of the inner device were the next most important reasons (4 of 43 [9.3%] each). Overall, the 10-year cumulative survival rate of CI surgery was 94.4%, and the device survival rate was 96.0%. Thirteen different CI devices from 4 different manufacturers were implanted, and no meaningful differences in device failure were found among CI manufacturers or devices (hazard ratios for cumulative survival: Cochlear, 1.67 [95% CI, 0.72-3.88]; Advanced Bionics, 1.67 [95% CI, 0.61-4.53]; Med-El, reference; hazard ratios for device survival: Cochlear, 1.65 [95% CI, 0.55-4.99]; Advanced Bionics, 1.93 [95% CI, 0.56-6.74]; Med-El, reference). Several recalls were issued by manufacturers during the study period, and after excluding the recalled devices, the device survival rates for 5, 10, and 15 years were 98.2%, 97.7%, and 94.9%, respectively.

Conclusions and Relevance

Generally, implanted devices remain safe and stable for a long time, and no significant differences in survival rates were found between device types or manufacturers. Device failure was the main reason for CI revision, followed by flap-associated problems and migration of the inner device.

Management of Complications in 1452 Pediatric and Adult Cochlear Implantations

Objective

The aim of this study was to determine the short- and long-term complications after cochlear implantation (CI) procedures and to discuss the management and prevention of these complications.

Methods

The study included a total of 1452 pediatric and adult cochlear implantation procedures performed in our clinic from March 2000 through September 2019. Of the 1452 implantations, 1201 were performed in children and 156 in adults. The minimum follow-up period was three months and maximum was 19 years. The mean age of the patients was 6.7±3.9 years (range, 10 months-69 years) at the time of their respective procedures. Complications were classified as major complications requiring reimplantation, major complications not requiring reimplantation and minor complications. All postoperative complications and treatment methods were examined.

Results

A total of 148 (10.1%) complications were observed in the 1452 cochlear implants. Of these, 69 (4.75%) were major and 79 (5.44%) were minor complications. While 40 (2.75%) of the major complications required reimplantation, 29 (1.99%) did not. The most common cause of major complications leading to reimplantation was device failure (29 patients, 1.99%). The most common cause of minor complications was hematoma (21 patients). Total complication rates (6.68%) were significantly higher in children than in adults (3.51%) (p=0.00).

Conclusion

Our 19 years of clinical experience has shown that CI is a successful and safe procedure that can be performed with low major complication rates. It is important to know the possible complications and to manage them correctly.

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

OBJECTIVES

To explore the causes of cochlear implantation and reference function of old electrical stimulation electrode in cochlear reimplantation in children.

METHODS

The 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.

RESULTS

Twenty-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).

CONCLUSION

The old stimulus electrode can provide an important reference to reduce the risk of operation and ensure the success of the reoperation.

Twenty years of experience in revision cochlear implant surgery: signs that indicate the need for revision surgery to audiologists

OBJECTIVE

To report device failures, audiological signs and other reasons for revision cochlear implant surgery, and discuss indications for revision surgery.

METHODS

Revision procedures between November 1997 and August 2017 were retrospectively analysed. Over 20 years, 2181 cochlear implant operations were performed, and 114 patients underwent 127 revision operations.

RESULTS

The revision rate was 4.67 per cent. The full insertion rate for revision cochlear implant surgery was 88.2 per cent. The most frequent reasons for revision surgery were: device failure (59 per cent), wound breakdown (9.4 per cent) and electrode malposition (8.7 per cent). The device failure rate was: 2.78 per cent for Advanced Bionics, 1.82 per cent for Cochlear and 5.25 per cent for Med-El systems. The number of active electrodes was significantly increased only for Med-El devices after revision surgery. The most common complaints among 61 patients were: gradually decreased auditory performance, sudden internal device shutdown and headaches.

CONCLUSION

The most common reason for revision surgery was device failure. Patients should be evaluated for device failure in cases of: no hearing despite appropriate follow up, side effects such as facial nerve stimulation, and rejection of speech processor use in paediatrics. After revision surgery, most patients have successful outcomes.

Feasibility of Revision Cochlear Implant Surgery for Better Speech Comprehension

Background and Objectives

The purpose of this study was to evaluate the efficacy of revision cochlear implant (CI) surgery for better speech comprehension targeting patients with low satisfaction after first CI surgery.

Subjects and Methods

Eight patients who could not upgrade speech processors because of an too early CI model and who wanted to change the whole system were included. After revision CI surgery, we compared speech comprehension before and after revision CI surgery. Categoies of Auditory Performance (CAP) score, vowel and consonant confusion test, Ling 6 sounds, word and sentence identification test were done.

Results

The interval between surgeries ranged from eight years to 19 years. Same manufacturer’s latest product was used for revision surgery in six cases of eight cases. Full insertion of electrode was possible in most of cases (seven of eight). CAP score (p-value=0.01), vowel confusion test (p-value=0.041), one syllable word identification test (p-value=0.026), two syllable identification test (p-value=0.028), sentence identification test (pvalue=0.028) had significant improvement. Consonant confusion test (p-value=0.063), Ling 6 sound test (p-value=0.066) had improvement but it is not significant.

Conclusions

Although there are some limitations of our study design, we could identify the effect of revision (upgrade) CI surgery indirectly. So we concluded that if patient complain low functional gain or low satisfaction after first CI surgery, revision (device upgrade) CI surgery is meaningful even if there is no device failure.

When to replace legacy cochlear implants for technological upgrades: Indications and outcomes

OBJECTIVE

To determine indications, surgical efficacy, and audiologic outcomes of replacing Advanced Bionics Clarion C1.2 internal devices (Advanced Bionics, LLC, Valencia, CA) as a means of technology upgrade.

STUDY DESIGN

Retrospective review, case series.

METHODS

Ten patients were initially implanted as a child (mean age = 3.87 years) and underwent cochlear implant reimplantation (CIR) with current Advanced Bionics internal device as a young adult (mean duration of implant use = 15.66 years). Demographic data and pre- and post-CIR speech perception scores were collected.

RESULTS

Technology upgrade was the primary (9) or secondary (1) motivation for CIR. No surgical complications were noted, and full insertion was obtained in nine cases. Intraoperative impedance levels and neural response imaging measures were within normal limits for eight patients. At most recent post-CIR follow-up evaluation, all patients (100%) performed within or better than the 95% confidence interval of their pre-CIR word and sentence recognition scores; and 55.6%, 50.0%, and 50.0% of patients performed above the 95% confidence interval of their pre-CIR scores for the CNC words, sentences in quiet, and sentences in noise, respectively.

CONCLUSION

Post-CIR audiological benefit was stable or improved compared to pre-CIR results in all categories by 3 months after reactivation. Given these results, patients who are unable to use the most current external processors due to incompatibility with a legacy internal device could consider reimplanation to optimize their overall performance with a cochlear implant.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:748-753, 2019.

Comparison of MRI in pediatric cochlear implant recipients with and without retained magnet

OBJECTIVE

To report and compare medical, radiological, and audiological outcomes in pediatric cochlear implant recipients who underwent 1.5 and 3 Tesla strength MRI with and without retained magnet.

METHODS

Retrospective chart review at a tertiary care pediatric hospital and review of literature. Patients were identified via electronic medical records database search and were included if they had MRI after cochlear implant.

RESULTS

Of twelve instances of MRI in pediatric cochlear implant recipients at our institution, two minor complications and one major complication were recorded. The rate of complication was equal between patients who underwent MRI with and without retained magnet. All minor complications resulted from MRI with retained magnet whereas the only major complication resulted from magnet removal. Two novel complications are reported, including: magnet removal resulting in silastic tear necessitating reimplantation and magnet dislocation with spontaneous reduction. Magnet removal significantly decreased the size of artifact, but did not alter the diagnostic utility of the MRI. While audiological measures varied chronologically from MRI scans, they did not appear to be appreciably altered by MRI.

CONCLUSION

MRI with and without magnet retention appear to carry risks of both major and minor complications. For the regions of interest for each scan, MRI quality was not appreciably altered by magnet status. Audiological measures appear unaffected by magnet status during MRI however, this may reflect natural variation.

Pediatric cochlear reimplantation: Decision-tree efficacy

OBJECTIVES

The 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.

METHODS

A 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).

RESULTS

69 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).

CONCLUSION

Apart 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.

Revision cochlear implant surgery in children: Surgical and audiological outcomes

OBJECTIVES/HYPOTHESIS

To determine the incidence of cochlear implant failure and to examine surgical and audiological outcomes.

STUDY DESIGN

Retrospective review, case series.

METHODS

This study sought indications for revision surgery, surgical findings, and outcomes, and audiological outcomes in pediatric cochlear implant patients. Pre- and postcochlear reimplantation word recognition performance was analyzed using a modified version of the Pediatric Ranked Order Speech Perception (PROSPER) score.

RESULTS

Over a 20-year period, a total of 868 cochlear implants were performed in 578 patients. The overall institutional reimplant rate was 5.9%. The indications for explantation were hard failure (30), soft failure (23), and medical/surgical indication (13). A significant portion of devices belonged to vendor recalled batches (15) or were damaged by head trauma (eight). Full electrode insertion was achieved in all 62 reimplantations. Post-reimplantation Boston Children's Hospital modified PROSER scores were either stable or improved compared to pre-reimplantation scores.

CONCLUSIONS

The need for cochlear implant revision/reimplantation is infrequent, but the rate is not inconsequential. Hard and soft device failures account for the majority of reimplants. Surgical complications during reimplantation is low, and post-reimplantation audiological performance is excellent.

LEVEL OF EVIDENCE

4. Laryngoscope, 2619-2624, 2018.

Cochlear Implantation in Postmeningitic Deafness

PURPOSE

The aim of this study is to evaluate long-term outcomes of cochlear implantation (CI) in patients with postmeningitic deafness.

METHODS

Twenty-seven patients with severe to profound hearing loss due to bacterial meningitis and received CI were the subjects of this study. Surgical findings and long-term audiological performances were evaluated. Speech perception and speech intelligibility of the implanted patients were evaluated with the categories of auditory performance-II (CAP-II) test and speech intelligibility rating (SIR) test, respectively.

RESULTS

Eighteen of the 27 patients had received full electrode insertion through the patent cochlear lumen. Remaining 9 patients had varying degrees of ossification throughout the cochlea and needed to be drilled to achieve partial electrode insertion. None of the patients exhibited surgical complication. Scores in both test batteries (CAP-II and SIR) were comparable between patients who received full or partial electrode insertion (P > 0.05).

CONCLUSION

Cochlear implantation after postmeningitic deafness has favorable outcomes especially in long term. Although this type of inner ear pathology may require special considerations during surgery, it is a relatively safe procedure.

Endoscope-Assisted Cochlear Implantation

OBJECTIVES

Our aim was to present our endoscope-assisted cochlear implantation (CI) technique, in which the middle ear landmarks were identified through the facial recess exposure by using an endoscopic view without elevating the tympanic annulus. The secondary goal was to assess whether the situation of difficult surgical exposure could be predicted by evaluating preoperative axial computed tomography (CT) examinations.

METHODS

CT examinations and surgical outcomes of endoscope-assisted CI surgeries were analyzed.

RESULTS

A total of 179 CI operations performed in 27 adults (15.1%) and 152 children (84.9%) were retrospectively evaluated. It was found that in 14 cases (7.8%), endoscopic examination contributed substantially in identifying the round window (RW) membrane correctly. Endoscopic identification of the RW through the posterior tympanotomy enabled us to perform a straightforward surgery in all these cases, without the need for switching to a bony cochleostomy or alternative surgical techniques. The difficulty in the surgical exposure was predicted preoperatively by examining the axial CT scans in six of the 14 cases (42.8%) for which endoscopic assistance was necessary in order to identify the RW correctly.

CONCLUSION

The main benefit of endoscope-assisted CI is the improved visibility leading to a panoramic view of the RW region. The implementation of transfacial recess endoscopic examination into the conventional CI technique is helpful to avoid problems during surgical orientation. However, the difficulty in the surgical exposure of the RW cannot be reliably predicted by the subjective evaluation of preoperative CT scans and more studies are needed to obtain reliable criteria.

Analysis and Management of Complications in a Cohort of 1,065 Minimally Invasive Cochlear Implantations

Objectives:

To analyze complications associated with minimally invasive cochlear implantation by comparing data from different centers, to discuss major reasons for complications, and to refine implantation techniques to decrease them.

Patients:

Patients who underwent cochlear implantation at our center by the same surgeon (the corresponding author of this article) from March 2006 to March 2015 were enrolled.

Intervention:

First, a retrospective analysis of the complications associated with minimally invasive cochlear implantation at our center was performed. Second, published reports from other centers that describe complications were reviewed. Differences between complications in our cohort and other studies were evaluated.

Main Outcome Measure:

Strategies for reducing complications were assessed and modifications in surgical protocol proposed accordingly.

Results:

In total, 1,014 patients underwent 1,065 cochlear implantations. There were 28 complications (7 major, 21 minor) and only 2 reimplantations for the entire cohort, with no case of severe infection, flap necrosis, or device extrusion. The major complications were electrode misplacement, magnet displacement, implant failure secondary to trauma, and temporary cerebrospinal fluid leakage. The rates of major complications in our cohort were very low (0.6%) compared with those in the literature.

Conclusion:

Preoperative surgical planning based on individual patient anatomy and employment of soft surgical techniques can minimize surgical complications.

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.

Outcomes after cochlear reimplantation in children

OBJECTIVES

With cochlear implantation now a routine procedure, reimplantation is becoming more commonplace for medical/surgical complications or device malfunctions. This study investigated the indications for reimplantation and the auditory outcomes following reimplantation surgery in prelingually-deafened children.

METHODS

Of the 539 prelingually deafened children implanted between 1990 and 2013, 45 were reimplanted (8.3% of implantations). Causes of reimplantation, type of device and angle of insertion at initial implantation were recorded, as well as type of implant reinserted, number of electrodes inserted and angle of insertion (calculated on cone beam computed tomography) on reimplantation, and finally any surgical findings. Speech perception test scores (phonetically balanced kindergarten (PBK) words, open-set sentence testing in quiet and in noise (S/N+ 10 dB SNR), and speech tracking scores) were obtained 1, 2 and 3 years after reimplantation, and compared against the best speech recognition score obtained with the first implant before failure.

RESULTS

Medical reasons for reimplantation were found in 10 cases (22.2%). A malfunctioning device had occurred in 35 cases (77.7%) including hard failure in 24 and soft failure in 11. Complete insertion was achieved in the scala tympani in 42 cases and in the scala vestibuli in one case; partial insertion occurred in the remaining two cases. In two cases, one or two electrode rings snatched off from the electrode array during removal. The mean insertion angle was 330.5° before surgery and 311.8° after reimplantation (no statistical difference p=0.48). The postoperative speech perception outcome measures showed no significant difference to the best score before reimplantation. Angle of insertion, type of device and etiology of deafness did not influence the results. The PBK performance improved over 10% in 43.2% of children, was similar in 40.5%, and showed a more than 10% decrease in 16.2% of children after reimplantation. The latter decline in performance was explained for some children by a partial insertion.

CONCLUSIONS

Reimplantation has no negative effect on auditory outcome. In rare cases, speech perception outcome may not improve, requiring a specific rehabilitation program.