Migration and other electrode complications following cochlear implantation.

OBJECTIVES: To investigate migration and other electrode-related complications in cochlear implant surgery. METHODS: Retrospective review of all patients (adult and paediatric) undergoing cochlear implantation at a tertiary referral centre in England, between April 2019 and December 2021. Split arrays and patients who did not have post-op imaging were excluded. RESULTS: Two hundred and ninety-nine cochlear implants were performed including 90% primary and 10% revision surgeries. Two hundred and forty-eight (86%) of electrodes implanted were straight arrays.Twenty-seven (9%) demonstrated suboptimal position on post-operative imaging. Three (11%) were true migration, 4 (15%) possible migration, 15 (56%) had two or less extra-cochlear electrodes, 3 (11%) expected partial insertion and 2 (7%) demonstrated tip fold-overs. Twenty (74%) of arrays within the suboptimal insertion group were in primary surgeries. Six patients required re-implantation. The most common reason for re-implantation was migration. DISCUSSION: Electrode migration after cochlear implantation may be more common than previously thought. We demonstrate rates of migration congruous with current literature; this is despite robust and varied fixation techniques. Notable in our series is that all true captured migrations were seen exclusively in straight arrays. The majority of patients in the possible and confirmed migration group had normal inner ear anatomy. CONCLUSION: Suboptimal electrode position following cochlear implant surgery is a recognized complication and can affect implant performance. Reporting may increase with more widespread use of sophisticated post-operative imaging. Use of a pre-curved electrode and routine use of appropriate fixation techniques may reduce migration rates.

Recurrent Swelling in Pediatric Cochlear Implant Patients.

OBJECTIVE: To determine the prevalence, characteristics, and outcomes of pediatric patients with recurrent swelling over their cochlear implant receiver package. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: A total of 332 bilateral cochlear implant patients under the age of 18 years were reviewed. Twelve patients with more than one episode of swelling around their cochlear implant receiver package were isolated. Patients with clinical evidence of infection were excluded from the study. The etiology of hearing loss was heterogeneous. INTERVENTION: Three patients underwent ultrasound, and three patients underwent bedside aspiration. Most patients were treated with 7 days of oral broad-spectrum antibiotics. MAIN OUTCOME MEASURE: Incidence, frequency, and course of recurrent swelling around cochlear implant receiver packages. RESULTS: The first swelling appeared between 0.86 and 9.95 years after surgery (mean, 3.38), and the occurrence of the last episode ranged from 0.06 to 3.42 years from the current date (mean, 1.04). The total number of episodes ranged from 2 to 18 (mean, 6). Seven patients had unilateral swellings, and five had bilateral swellings. Swellings were associated with upper respiratory tract infection or minor trauma, or had no identifiable cause. Aspiration in three cases showed evidence of altered blood. CONCLUSIONS: Recurrent otherwise asymptomatic swelling over cochlear implant receiver packages in children is more common than initially thought. Possible causes include hematoma and seroma secondary to upper respiratory tract infection. The incidence and the timing of swelling are variable. There were no swelling-related device failures or reimplantations so patients and parents can be reassured about the long-term outcome.

Do Filling Defects of the Vestibule Represent a Neuroradiological Marker for Congenital Cytomegalovirus? A Retrospective Case Series.

INTRODUCTION: The aim of this study was to investigate whether radiological marker(s) of the inner ear can be detected in congenital cytomegalovirus (cCMV) patients with severe-profound sensorineural hearing loss. METHODS: A retrospective imaging review of confirmed cCMV paediatric patients that had undergone consecutive cochlear implantation was performed at a tertiary hospital. Available pre- and postoperative imaging was examined, and abnormalities of the labyrinth were catalogued by a consultant neuroradiologist in the study group and control group. RESULTS: Twenty-eight paediatric patients with cCMV having undergone cochlear implantation were identified between the ages of 1-15 years (mean 4.7 years) at the time of implantation. Increased density of the vestibule on computed tomography (CT) or filling defects of the vestibule on magnetic resonance imaging (MRI) were identified in 11 and 4 patients, respectively, of the 24 in the case series. No filling defects were identified in any of the 48 CT and MRI control group. CONCLUSION: This study demonstrates a potential novel radiological finding of the inner ear of patients with cCMV. With more research, greater onus placed on MRI and CT for inner ear assessment may facilitate early detection and treatment for patients at risk of significant hearing loss. Further prospective studies in this area will help to validate radiological markers in order to establish a comprehensive inner ear classification system for neuroradiological features in cCMV.

Cochlear implant outcomes in patients with Meniere's disease: a large case series.

OBJECTIVE: To perform a matched cohort study to assess whether patients with Meniere's Disease (MD) require more intensive auditory rehabilitation following cochlear implantation (CI) and identify factors that may affect outcomes in patients with MD. METHODS: A retrospective case review was performed. MD and control patients were matched for age, biological sex, implant manufacturer and electrode design. Outcomes measured were speech scores, number of visits to audiology department following switch-on, and post-operative active MD. RESULTS: Forty consecutive implanted MD patients were identified between May 1993 and May 2019. Patients with active MD following CI required significantly more visits to the audiology department compared to controls (P < 0.01) and patients who had inactive MD post-operatively (P < 0.01). However, in MD patients, active MD was less likely following CI (P = 0.03). In patients who continued to experience active MD post-operatively, further medical and surgical ablative intervention was required to control ongoing Meniere's attacks. CONCLUSION: We present the largest case series of performance outcomes in CI patients with MD. Although speech outcomes in MD patients are comparable to controls, patients with active MD pre-operatively are more likely to experience variation in CI performance requiring a prolonged period of auditory rehabilitation compared to inactive preoperative MD.

Patient, parental and multi-disciplinary team rationale for non-implantation following the paediatric cochlear implantation assessment.

OBJECTIVES: To assess paediatric patients referred to the cochlear implant team, who despite undergoing the assessment, did not receive cochlear implantation. To identify the underlying reasons for this. METHODS: A retrospective case-note review of patients was assessed from June 2014 to June 2019 at two separate London teaching hospitals with paediatric cochlear implantation programmes. RESULTS: A total of 921 paediatric patients were assessed during the study period across both institutions. And, 196 (21%) did not proceed with the surgery. The decision not to undergo surgery was primarily parental/patient-directed in 114 (61%) and cochlear implant team-directed in 74 (39%). In total, eight (4%) patients exited the programme without a documented reason. DISCUSSION: A myriad of factors influenced the decision-making process for clinicians, patients and parents. The most cited parental/patient rationale against implantation was the wish to continue current means of communication 40 (35%), followed by concern regarding the risks of surgery 18 (15.8%) and the wish to allow the patient to make future decisions independently in view of the future technology 7 (6.1%). Cochlear implant team-directed decisions were largely due to being outside of the NICE criteria 27 (36.5%) or the risks of general anaesthesia 19 (25.7%) in addition to communication concerns 11 (14.9%). CONCLUSION: Decision-making in cochlear implantation should not be underestimated. Extensive discussion and exploration of options with the multi-disciplinary team can aid decision-making, but the timescale and appreciation of the consequences of the decision inevitably lead to pressure. Exploration of reasons for non-implantation emphasises the importance of a multi-professional approach to manage these patients.

Hearing Preservation Outcomes With Standard Length Electrodes in Adult Cochlear Implantation and the Uptake of Electroacoustic Stimulation.

BACKGROUND: Cochlear implantation with preservation of residual low-frequency hearing enables patients to utilize acoustic and electrical stimulation. It is widely accepted that preservation of residual low-frequency hearing is beneficial in both background noise and for music appreciation. The extent to which patients may benefit is not fully understood, but the importance of these concepts is reflected in electrode design developments and also refinement of surgical technique. Greater understanding is needed around factors that may affect hearing preservation. This study reports experience in adults using standard length cochlear implant arrays. OBJECTIVE: The study reviews hearing preservation outcomes using the HEARRING GROUP method for factors such as gender, electrode type, insertion depth, laterality, preoperative hearing level, and time between surgery and audiogram. Furthermore, the study reviews rates of electroacoustic stimulation use in those with postoperative functional residual low-frequency hearing. METHODOLOGY: Retrospective case series. INCLUSION CRITERIA: preoperative ≤ 85 dB HL at 250 Hz and aged ≥ 18 years. The hearing preservation percentages were calculated using the HEARRING group formula S=[1 - ((PTApost - PTApre)/(PTAmax - PTApre))*100]%. Preservation of > 75% was considered complete, 25 to 75% partial, and 1 to 25% minimal. Standardized operative technique with facial recess approach, posterior tympanotomy, and minimally traumatic round window insertion was performed for each implant. RESULTS: Fifty-three implantations in 52 patients met the inclusion criteria. The mean age at implantation was 55.5 years. The average time since the last audiogram was 10 months. The mean average total pre and postoperative pure-tone averages were 92.4 dB, 99.2 dB, respectively, using minimum reporting standards for adult cochlear Implant (CI). Thirty percent demonstrated complete hearing preservation, 35.8% partial hearing preservation, and 20.8% minimal hearing preservation. Overall, mean hearing preservation was 52.9%. Sex, age at implantation, insertion depth, lateral versus perimodiolar electrode, and preoperative hearing level did not statistically significantly affect rates of hearing preservation in our study. There was a statistically significant deterioration in hearing preservation outcomes difference at 3 months compared with 12 months postoperatively. Only two patients within our study out of 17 with functional postoperative hearing went on to use electroacoustic stimulation. CONCLUSION: Hearing preservation varies between patients and postoperative outcomes are difficult to predict. This study adds to existing literature in terms of likelihood of hearing preservation following cochlear implantation. In turn, this improves our ability to counsel patients as to the chances of preserving residual low-frequency hearing postoperatively and their ability to use electroacoustic stimulation.

Three New Mutations and Mild, Asymmetrical Phenotype in the Highly Distinctive LAMM Syndrome: A Report of Eight Further Cases.

Labyrinthine aplasia, microtia, and microdontia (LAMM) is an autosomal recessive condition causing profound congenital deafness, complete absence of inner ear structures (usually Michel's aplasia), microtia (usually type 1) and microdontia. To date, several families have been described with this condition and a number of mutations has been reported. We report on eight further cases of LAMM syndrome including three novel mutations, c. 173T>C p.L58P; c. 284G>A p.(Arg95Gln) and c.325_327delinsA p.(Glu109Thrfs*18). Congenital deafness was the primary presenting feature in all affected individuals and consanguinity in all but two families. We compare the features in our patients to those previously reported in LAMM, and describe a milder, asymmetrical phenotype associated with FGF3 mutations.

Intratympanic Steroid Use for Sudden Sensorineural Hearing Loss: Current Otolaryngology Practice.

OBJECTIVE: To investigate the current practice of intratympanic steroid (ITS) injection for sudden sensorineural hearing loss (SSNHL) in the United Kingdom and link the data with data from the United States and continental Europe. METHODS: A survey of 21 questions was distributed to members of the British Society of Otology using an online survey platform via ENT UK. Data obtained from UK otolaryngologists (n = 171) were integrated with previously published data from other countries, including the United States (n = 63) and continental Europe (n = 908). RESULTS: In the United Kingdom, 62% of responding otolaryngologists use ITS injection for SSNHL, while 38% do not. Of those using ITS, 59% use it as first-line treatment, either using it in conjunction with oral steroids (51%) or using it as monotherapy (8%). Of those that use ITS, a majority (83%) use it as salvage therapy when primary treatment with systemic steroids has failed, and similar results are found in the continental Europe and US surveys. The most commonly used preparation is dexamethasone. Responses to questions regarding treatment regimes used are enlightening and show considerable variation in the treatment regimes used within and between countries. CONCLUSIONS: There is a wide variation in practice with regards to ITS for SSNHL hearing loss in the United Kingdom, United States, and continental Europe. In the absence of protocols or definitive guidance from published literature, knowledge of contemporary practice may help guide or encourage reevaluation of clinical practice and will help guide the design of future clinical trials.

Recurrent cochlear implant associated seroma: A series of five patients.

Introduction: We have observed a small number of patients with cochlear implants who have a tendency to develop recurrent seromas overlying the implant package. Methods: Five patients with a current or previous history of recurrent seromas presenting for review over a three-month period were identified. A retrospective review of their case notes was undertaken. Results: All patients identified were children, with a mean age at first seroma of 5.0 years (range 1.9-10.4 years). The mean interval between implantation and first episode of seroma was 3.1 years (range 0.9-6.4 years). With the exception of imaging showing a fluid-density collection, investigations were generally unremarkable. Fluid aspirated from one patient was cultured and no organisms were grown. Antibiotics, most commonly amoxicillin / clavulanic acid, were commonly but not universally prescribed. Conclusions: Recurrent cochlear implant associated seroma appears to be an idiopathic process. Investigations are generally unhelpful, and whilst it is probably prudent to treat with antibiotics during an initial presentation, once a pattern of recurrent seroma is established, patients can be treated conservatively.

Hearing Preservation With Standard Length Electrodes in Pediatric Cochlear Implantation.

OBJECTIVE: Preserving low frequencies following cochlear implantation improves outcomes and allows patients to use a combination of electrical and acoustic stimulation. This importance has been reflected in advances in electrode design and refined surgical techniques. Full insertion of standard length electrodes may be advantageous over shortened electrodes because more electrodes can be activated over time if low frequency hearing loss progresses. Surgeons must counsel patients over this choice but data is lacking regarding the degree and likelihood of hearing preservation achievable with standard length electrodes in children. We report our experience using standard length cochlear implant arrays for hearing preservation in children. METHODS: Retrospective case series. INCLUSION CRITERIA: preoperative hearing ≤85 dB HL at 250 Hz and aged ≤18 years. Hearing preservation percentages are calculated using the HEARRING group formula. (Equation is included in full-text article.)Preservation of > 75% was considered complete, 25 to 75% partial, and 1 to 25% minimal. Patients were implanted with either MED-EL FLEX28 or Cochlear Nucleus CI522. Standardized operative technique with facial recess approach, posterior tympanotomy and minimally traumatic round window insertion. RESULTS: Fifty-two implantations in 27 pediatric patients met inclusion criteria. Mean age at implantation: 9.8 years. Average latest audiogram: 8 months. Mean total pre- and postoperative pure-tone averages were 82.8 and 92.6 dB. Seventeen (33%) ears demonstrated complete hearing preservation, 22 (42%) ears partial hearing preservation, 7 (13%) minimal hearing preservation, and 6 (12%) exhibited no acoustic hearing postoperatively. Mean hearing preservation was 55.5%. CONCLUSION: Hearing preservation is achievable to varying degrees in pediatric cochlear implantation using standard length electrodes though it is difficult to predict preoperatively which children may benefit. This study is among the largest additions to the knowledge base for this patient group.

Development of electrophysiological and behavioural measures of electrode discrimination in adult cochlear implant users.

The plasticity of the auditory system enables it to adjust to electrical stimulation from cochlear implants (CI). Whilst speech perception may develop for many years after implant activation, very little is known about the changes in auditory processing that underpin these improvements. Such an understanding could help guide interventions that improve hearing performance. In this longitudinal study, we examine how electrode discrimination ability changes over time in newly implanted adult CI users. Electrode discrimination was measured with a behavioural task as well as the spatial auditory change complex (ACC), which is a cortical response to a change in place of stimulation. We show that there was significant improvement in electrode discrimination ability over time, though in certain individuals the process of accommodation was slower and more limited. We found a strong relationship between objective and behavioural measures of electrode discrimination using pass-fail rules. In several cases, the development of the spatial ACC preceded accurate behavioural discrimination. These data provide evidence for plasticity of auditory processing in adult CI users. Behavioural electrode discrimination score but not spatial ACC amplitude was found to be a significant predictor of speech perception. We suggest that it would be beneficial to measure electrode discrimination in CI users and that interventions that exploit the plastic capacity of the auditory system to improve basic auditory processing, could be used to optimize performance in CI users.

Evaluating inter-aural hearing preservation in bilateral paediatric cochlear implantation.

OBJECTIVE: To examine inter-aural hearing preservation results in children undergoing simultaneous bilateral cochlear implantation (CI). METHODS: Retrospective case review in tertiary referral centre. All children undergoing simultaneous bilateral CI between January 2013 and June 2014 (18 months). Patients eligible for inclusion in the study had pre-operative hearing thresholds of <90 dB at 250 Hz and ≥100 dB at 500 Hz. Patients with anatomical cochlear anomalies or missing data were excluded. Seven patients were included, 1 male, 6 female, mean age of 12 years 11 months at the time of surgery. All patients had simultaneous bilateral cochlear implant surgery, using the same implant and technique. All patients had pre- and post-operative unaided pure tone audiometry. Inter-aural hearing preservation results were compared in each patient. RESULTS: The achieved hearing preservation for 14 ears was complete in 5, partial in 7, and minimal in 2. Measurable hearing preservation was achieved in 86% overall. Inter-aural analysis revealed that only 2 (subjects 1 and 4) of the 7 patients had preservation results within the same preservation group (complete/partial/minimal). The mean inter-aural preservation difference was 30.7% with a range from 12.4% to 65.2%. CONCLUSIONS: Several factors and techniques have already been identified in the wider literature to explain differences in hearing preservation results in CI. However, despite controlling for known factors, we demonstrate variable inter-aural results. This suggests that there may be more factors beyond the surgeon's control influencing our ability to provide consistent results.

Objective assessment of electrode discrimination with the auditory change complex in adult cochlear implant users.

The spatial auditory change complex (ACC) is a cortical response elicited by a change in place of stimulation. There is growing evidence that it provides a useful objective measure of electrode discrimination in cochlear implant (CI) users. To date, the spatial ACC has only been measured in relatively experienced CI users with one type of device. Early assessment of electrode discrimination could allow auditory stimulation to be optimized during a potentially sensitive period of auditory rehabilitation. In this study we used a direct stimulation paradigm to measure the spatial ACC in both pre- and post-lingually deafened adults. We show that it is feasible to measure the spatial ACC in different CI devices and as early as 1 week after CI switch-on. The spatial ACC has a strong relationship with performance on a behavioural discrimination task and in some cases provides information over and above behavioural testing. We suggest that it may be useful to measure the spatial ACC to guide auditory rehabilitation and improve hearing performance in CI users.

Assessment and Outcome in Non-Traditional Cochlear Implant Candidates.

The objectives of this study were to assess: (i) patient expectations met as a measure of outcome in early-deafened, late-implanted (non-traditional) cochlear implant recipients and (ii) pre-implantation predictive factors for postoperative speech perception. The notes of 13 recipients were retrospectively reviewed. The mean age at onset of profound deafness was 1.5 years (range 0-6). The mean age at implantation was 37 years (range 22-51 years). Patient expectations were assessed pre-operatively and 1 year after implantation. They were met or exceeded in 129/140 (92%) domains overall. A higher Speech Intelligibility Rating and audiovisual City University of New York sentence score before implantation were found to be positive predictive factors for improved speech discrimination after cochlear implantation.

Neurofibroma of the pinna.

Neurofibromas are relatively common lesions of the nervous system, but only a few cases involving the pinna have been reported. The emphasis in most of these reports was on the cosmetic deformity; functional impairment in the form of hearing loss has been mentioned in only a few reports. We report a case of pinnal neurofibroma in which the primary complaint was otitis externa; hearing loss and cosmetic deformity were also present. Surgical excision resulted in an excellent functional and cosmetic outcome. This case demonstrates that neurofibroma of the pinna in the area of the external meatus can produce functional as well as cosmetic impairment, and surgery can produce a very satisfactory result.