In an era of bilateral funding and changing criteria, when is unilateral cochlear implantation a better option?

BACKGROUND: Funding for paediatric bilateral cochlear implantation became available in Ireland in 2014. Prior to this, children eligible for cochlear implantation received a unilateral implant. OBJECTIVE: To examine the cohort of children who received a unilateral cochlear implant in the 4 year period following bilateral cochlear implantation funding becoming available. METHODS: A clinical audit of all children implanted for the first time between July 2014 and July 2018. The unilaterally implanted children (n = 105) were divided into 3 groups according to whether they met the audiometric thresholds for implantation in neither ear (Group 1), one ear (Group 2) or both ears (Group 3). One year post operative functional outcomes were examined for all 3 groups. RESULTS: All 3 groups showed significant improvements in functional outcomes at 1 year post op. To date, 20% of the unilaterally implanted children have proceeded to get a sequential CI, often where there was no change in audiological status. CONCLUSIONS: The number of children in Groups 1 and 2 highlighted how our decision making around cochlear implantation has changed in recent years. Unilateral cochlear implantation in certain circumstances is good practice, independent of the audiological profile when an experienced multi-disciplinary team (MDT) is involved in the decision making process. Decision making using a holistic model approach is key, including involving the parent/carer and, where appropriate, the child/teenager themselves. A staged bilateral cochlear implant is also a good option, where careful monitoring and support for the first implant has resulted in positive outcomes.

National study of hearing preservation rates and outcomes after cochlear implantation in Ireland.

OBJECTIVE: To study the rate of hearing preservation and outcomes of hearing preservation candidates in a national cochlear implant centre. The HEARRING criteria was used. METHODS: All cochlear implant candidates with preserved low frequency pure tone average (PTA) were included. All patients underwent cochlear implantation using a standard 'soft-surgery' technique. PTA was assessed at switch-on, 3, 6, 9 and 12 months postoperatively. The primary outcome was hearing preservation at 12 months. RESULTS: Sixty six patients were included in the study between 2015 and 2020. Seventy one ears were implanted including 33 adults and 33 children with 5 bilateral implantations. Mean preoperative PTA was 74.8 dB (range 52.3-92 dB), mean postoperative PTA was 95.3 dB corresponding to a mean shift of 20.5 dB. In the adult population, HP rates were as follows: complete HP in 13%, partial HP in 39.1%, minimal HP in 30.4%, loss of hearing in 17.4%. In the paediatric population: complete HP in 20.7%, partial HP in 51.7%, minimal HP in 13.8% and loss of hearing in 13.8%. After the initial postoperative shift, there was no significant worsening of residual hearing during follow-up between 3 and 12 months. There were no significant prognostic factors for hearing preservation. CONCLUSION: Hearing preservation rates using the HEARRING criteria are described. This study will help counselling and decision making in patients eligible for cochlear implantation with hearing preservation. Further studies are required to assess the performances and outcomes of electronatural and electroacoustic stimulation.

Persistent Stapedial Artery Encountered during Cochlear Implantation.

OBJECTIVES: Persistent stapedial artery (PSA) is a rare congenital anomaly that can complicate middle ear surgery. METHODS: We present the case of a 25-year-old male who underwent right-sided cochlear implantation. A PSA was encountered lying over the middle promontory intraoperatively. RESULTS: The PSA was carefully lifted off the middle ear promontory using a Hughes elevator to divide adhesions and delineate the artery. The implant electrode was placed through the round window niche in the usual fashion. Tragal cartilage and fibrin glue were used to control the trajectory of the electrode. CONCLUSION: Cochlear implantation can be performed safely in patients with PSA.

New approach in programming sequentially implanted children: Towards balanced dynamic ranges (DR).

There is a tendency for children undergoing sequential cochlear implant after a long period of unilateral implant use to have a smaller dynamic range in their second implant compared to their first implant. This study aimed to investigate if balancing the dynamic ranges between the two implants influenced functional outcomes in sequentially implanted children. Nineteen participants with long inter-implant time delays were randomly assigned to a study group or a control group. Children in the study group received progressive minimal changes to both first and second implants over a period of nine months to achieve balanced dynamic ranges, while the children in the control group received only changes to their sequential implant. Functional outcomes were collected 24-months after sequential implantation and consisted of speech discrimination scores, spatial localisation, device use and quality of life measures. Results show that spatial discrimination skills improved over time for both groups of children; however children in the study group had smaller localisation errors compared with the children in the control group. No other differences between the two groups were observed. Balanced dynamic ranges in sequentially implanted children can contribute to better performance, particularly in spatial discrimination tasks that rely in inter-aural level differences.

Listening and spoken language outcomes after 5 years of cochlear implant use for children born preterm and at term.

AIM: To compare listening and spoken language outcomes after cochlear implantation for children born preterm and at term, and to examine patterns associated with additional disabilities or gestational age. METHOD: Children were included if they underwent cochlear implantation in 2013 or 2014 and had complete 5-year follow-up data available. An analysis of assessment data recorded annually was conducted, including outcomes as measured by the Category of Auditory Performance (CAP), the Speech Intelligibility Rating, Second Edition (SIR 2) scale, and the British Picture Vocabulary Scales, Third Edition (BPVS-3). Analyses were conducted to measure the impact of preterm birth and of additional causes of disability on these outcomes. RESULTS: Eighty-two children (39 males, 43 females; median corrected age at first cochlear implantation 28.5mo [interquartile range 16.3-48.5]) were included in the study. Children who underwent cochlear implantation experienced significant improvements as measured by the CAP, SIR 2, and BPVS-3. Comparable improvements were seen in the groups born at term and preterm. Children with additional disabilities experienced significant improvement in all measures but performed less well than children without additional disabilities. INTERPRETATION: Infants born preterm benefit from cochlear implantation to a degree comparable to their peers born at term. Additional disabilities may limit improvements in speech intelligibility, listening performance, and receptive vocabulary. Children with additional disabilities, nonetheless, derived significant benefit from cochlear implantation; additional benefits of cochlear implantation for this subgroup may go unmeasured by the outcome tools used in this study.

A retrospective review of parents' perceptions of the impact of bilateral cochlear implants on their child's quality of life.

OBJECTIVE: To evaluate the impact of simultaneous and sequential bilateral cochlear implantation on deaf children's quality of life (QoL) and to investigate the impact of inter-implant time delay for the sequentially implanted children. METHODS: All completed questionnaires of the Brief Assessment of Parental Perception (BAPP), which had been routinely filled out by parents at annual review, were analysed for children with at least 12 months of bilateral implant experience. The responses for the simultaneous implanted group were compared to those who received sequential implants. Within the sequential group, the impact of shorter (<7 years) and longer (>7 years) inter-implant delays on QoL were compared. RESULTS: There were a total of 176 children in the sequential group and 97 in the simultaneous group. Results indicated that most children wore their devices regularly and significant improvements in QoL were reported for all children particularly in communication and learning. QoL scores were higher for the children with simultaneous implants, followed by children with a shorter time delay between implants. CONCLUSION: Both simultaneous and sequential bilateral cochlear implants significantly improved the functioning and QoL of deaf children.

The Royal College of surgeons multidisciplinary guidelines on elective tracheostomy insertion in COVID-19 ventilated patients.

BACKGROUND: The current COVID-19 pandemic has placed enormous strain on healthcare systems worldwide. Understanding of COVID-19 is rapidly evolving. Pneumonia associated with COVID-19 may lead to respiratory failure requiring mechanical ventilation. The rise in patients requiring mechanical ventilation may lead to an increase in tracheostomies being performed in patients with COVID-19. Performing tracheostomy in patients with active SARS-CoV-2 infection poses a number of challenges. METHODS: These guidelines were written following multidisciplinary agreement between Otolaryngology, Head and Neck Surgery, Respiratory Medicine and the Department of Anaesthetics and Critical Care Medicine in the Royal College of Surgeons in Ireland. A literature review was performed and a guideline for elective tracheostomy insertion in patients with COVID-19 proposed. CONCLUSION: The decision to perform tracheostomy in patients with COVID-19 should be undertaken by senior members of the multidisciplinary team. Steps should be taken to minimise risks to healthcare workers.

Management of Temporal Bone Malignancy in Ireland.

Objectives Lateral temporal bone malignancy remains a challenging rare disease. We report 17 years of multidisciplinary care of these tumors with univariate and multivariate analyses of key prognostic indicators for consideration in contemporary oncological management. Design This is a retrospective cohort study. Setting This is set at a tertiary referral center. Participants All patients presenting with histopathologically newly diagnosed cases of temporal bone malignancy between 2000 and 2017 were included. Main Outcome Measures The main outcome measures are disease-specific and recurrence-free survival rates. Results In this study, 48 cases of temporal bone malignancy were diagnosed. Median age at diagnosis was 69 years (range: 5-88). Fourteen patients were female. Squamous cell carcinoma was the predominant malignancy in 34 cases (71%). Surgical treatment was undertaken in 37 patients. Mean length of follow-up was 32 months (range: 0.7-117). Overall 5-year disease-specific survival was 52.4%, while overall 5-year recurrence-free survival was 53.5%. On univariate analysis, significantly worse survival was seen in females ( p = 0.008), those with distant metastatic disease ( p = 0.041), and in middle ear involvement ( p = 0.012) with no difference for involvement of the external auditory canal ( p = 0.98) or mastoid ( p = 0.78). Only middle ear involvement remained significant on multivariate analysis. Conclusion A wide variety of malignant pathology may present in the temporal bone. Recurrence-free survival is equivalent to international data; however, this figure is low. This emphasizes the need to treat these tumors appropriately with radical resection, where possible, at first presentation. Therefore, multidisciplinary surgical input is recommended. Middle ear involvement was a negative prognosticator for disease-specific and recurrence-free survivals.

Sequential bilateral implantation in older children: Inter-implant map differences and their effects on functional outcomes.

OBJECTIVES: It is well established that sequential bilateral implantation offers functional benefits in speech in noise and sound localisation, although it can be challenging to get long-term unilateral users to adapt to the second implant. The aim of this study was to investigate programming differences between the two cochlear implants that can impact on performance outcomes. DESIGN: Cohort Study. PARTICIPANTS: Sixteen older children who received sequential implants in Ireland and with at least one-year experience with their sequential implant were included in this study. Children were categorised into two groups according to the time interval between the two implants: short if the time between the two implants was less than eight years and long if more than eight years. MAIN OUTCOME MEASURES: Dynamic ranges and current levels were compared for both implants. Functional outcome measures included sentence discrimination in quiet and in noise and sound localisation. RESULTS: Results show that for the children with long inter-implant delays, the dynamic range of their second implant was on average 34% less than the dynamic range of their first implant. This difference was driven by smaller comfort levels in the second implant compared to the first. Children with longer inter-implant delays also show lower speech discrimination scores with their second implant compared to children with shorter delays, in addition to no bilateral advantage in speech in noise, that is their performance in unilateral mode does not differ from the performance in bilateral mode. Finally, children with longer delays demonstrate poor performance in sound localisation compared to the children with shorter delays. CONCLUSION: Sequentially implanted older children show limited functional benefits from the second implant. The observed functional benefits are determined both by a short inter-implant delay and by having balanced dynamic ranges between the two implants.

Impact of Universal Newborn Hearing Screening on cochlear implanted children in Ireland.

OBJECTIVES: Cochlear Implant (CI) is an established treatment for severe to profound hearing loss (HL). Early diagnosis and intervention in HL are crucial in order to provide access to sound and increase the likelihood of spoken language development in pre-lingually deaf children. In April 2011, the Health Service Executive (HSE) implemented the Universal Newborn Hearing Screening (UNHS) in a phased regional basis in Ireland. This study aimed to investigate the general clinical pathway for UNHS referrals to the CI service and to evaluate the impact of earlier referrals via UNHS on functional outcomes in children. METHODS: The first part of this study constituted a retrospective review of 100 children referred to the National Hearing Implant and Research Centre (NHIRC) via UNHS from November 2011 to December 2016. Implanted children referred via UNHS were categorised into three groups according to their medical status. Their clinical pathway to cochlear implantation was evaluated. Functional outcomes were investigated based on medical and developmental status, respectively. In the second part of this study, developmentally healthy implanted children referred post-UNHS were compared with medically healthy children referred pre-UNHS under the age of four, from January 2005 to June 2011. Current implant status of children, age at referral and functional outcomes were investigated. RESULTS: Medically healthy children were referred to the NHIRC at an earlier age than the medically complex children (2.8 months vs 5.2 months, p < 0.01) and the children presenting with auditory neuropathy spectrum disorder (ANSD) (2.8 months vs 5.3 months, p < 0.01). On average they attended their first appointment and were implanted at a younger age than the ANSD group (6.1 months vs 10.1 months, p < 0.01; 16.3 months vs 29.4 months, p < 0.001, respectively). Developmentally healthy children had significantly better functional outcomes than children with developmental delays. Children referred via UNHS were referred and implanted at a younger age than those referred pre-UNHS. The former group achieved better Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores 2 years post-implantation. CONCLUSION: UNHS in Ireland is an important platform for earlier diagnosis and management of congenital HL and our results show that early intervention has a positive impact on functional outcomes in children.

The impact of repetitive hyperbaric exposure during SCUBA diving on cochlear implants.

OBJECTIVES/HYPOTHESIS: Complications during or after cochlear implantation are relatively rare. They occur more frequently in patients who partake in activities that can potentially lead to local trauma. No formal recommendations exist for participation in self-contained underwater breathing apparatus (SCUBA) activities. We describe three patients with a combined five cochlear implants and extensive diving experience, the largest case series to date, and highlight some of the difficulties faced. We also review the literature on previously described SCUBA-diving patients with cochlear implants. STUDY DESIGN: Retrospective case series and literature review. METHODS: A review of the known SCUBA divers in the National Hearing Implant and Research Centre in Ireland was conducted, and a review of the literature was carried out using PubMed and Google Scholar. RESULTS: Of the three SCUBA divers with cochlear implants, two required reimplantation, the first due to nonauditory stimulation, and the second due to extrusion of the electrode through the tympanic membrane following repetitive SCUBA dives. The third patient remains without complications after 80 dives. CONCLUSIONS: Patients with cochlear implants can have complications relating to the implant itself, with device failure a theoretical risk. The cochleostomy can lead to perilymphatic extravasation, as well as inner ear barotrauma, decompression sickness, and formation of air bubbles along the electrode. A combination of deafness, vestibulopathy with abrupt perilymph leak, and loss of proprioception can lead to disorientation and blue dome syndrome. Based on our experience with cochlear implants in SCUBA divers, along with those reported in the literature, we recommend caution in patients with cochlear implants who SCUBA dive regularly and strict adherence to the recommended safety limits. LEVEL OF EVIDENCE: 4 129:2760-2764, 2019.

Occurrence of major complications after cochlear implant surgery in Ireland.

OBJECTIVES: Cochlear implantation (CI) is considered an effective and relatively safe procedure for patients with severe-profound hearing loss. However, severe complications are reported in several studies. The purpose of this study was to report the frequency and management of major complications following CI surgery at the National CI Programme (NCIP) in Ireland. METHODS: Major complications were defined according to the classification of Hansen et al. 2010. The medical records of 1017 patients undergoing CI between 1995 and 2016 were analyzed retrospectively for major complications. In addition, radiological and intraoperative findings as well as therapeutic management of all patients with a major complication were reviewed. RESULTS: Altogether, 1017 patients underwent 1266 CI surgeries. The median follow-up of all CI surgeries was 44 months. The total number of major complications identified was 21 which corresponds to an overall rate of 1.7%. The majority of major complication (71%) occurred at least one week after surgery. The most common major complications were internal receiver/stimulator protrusion and migration (6/21), followed by migration of the electrode array (4/21) and recurrent otitis media requiring re-implantation (4/21). All patients with major complications required additional surgery, with reimplantation necessary in 19 patients (90%). DISCUSSION: CI surgery is a safe surgical procedure for hearing rehabilitation associated with a low rate of severe complications. However, major complications can occur many years after surgery, making revision surgery necessary. CONCLUSION: Long-term follow-up is necessary for the early identification of complications to facilitate appropriate care.

Quality of life outcomes in cochlear implantation of children with profound and multiple learning disability.

This study was performed to investigate the effect of cochlear implantation on the Quality of Life (QoL) of children with profound and multiple learning disability (PMLD). This cohort of children has been viewed historically as poor candidates for cochlear implantation as they generally have poor speech and hearing outcomes. The Irish National Cochlear Implant Program's prospectively maintained database was examined for all children implanted from July 1996 to July 2015. All charts of the 381 children implanted during this time were reviewed retrospectively; 16 children met criteria for being PMLD. For this cohort of patients, speech and hearing performance and the Glasgow Children's Benefit Inventory scores were retrospectively analyzed. Speech and hearing outcomes, as measured by Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores, demonstrated little or no improvement from pre-implantation to an interval 3 years post-op; however, 11 out of 16 parents reported an improvement in their child's quality of life after implantation with 3 out of 16 reporting no improvement. This study suggests that despite children with PMLD performing poorly on traditional outcome measures such as CAP and SIR they may have improvement to their QoL after cochlear implantation. Further study is warranted to characterize the impact of CI on these children.

Objective assessment of spectral ripple discrimination in cochlear implant listeners using cortical evoked responses to an oddball paradigm.

Cochlear implants (CIs) can partially restore functional hearing in deaf individuals. However, multiple factors affect CI listener's speech perception, resulting in large performance differences. Non-speech based tests, such as spectral ripple discrimination, measure acoustic processing capabilities that are highly correlated with speech perception. Currently spectral ripple discrimination is measured using standard psychoacoustic methods, which require attentive listening and active response that can be difficult or even impossible in special patient populations. Here, a completely objective cortical evoked potential based method is developed and validated to assess spectral ripple discrimination in CI listeners. In 19 CI listeners, using an oddball paradigm, cortical evoked potential responses to standard and inverted spectrally rippled stimuli were measured. In the same subjects, psychoacoustic spectral ripple discrimination thresholds were also measured. A neural discrimination threshold was determined by systematically increasing the number of ripples per octave and determining the point at which there was no longer a significant difference between the evoked potential response to the standard and inverted stimuli. A correlation was found between the neural and the psychoacoustic discrimination thresholds (R2=0.60, p<0.01). This method can objectively assess CI spectral resolution performance, providing a potential tool for the evaluation and follow-up of CI listeners who have difficulty performing psychoacoustic tests, such as pediatric or new users.

Auditory mismatch negativity in cochlear implant users: a window to spectral discrimination.

A cochlear implant (CI) can partially restore hearing in patients with severe to profound sensorineural hearing loss. However, the large outcome variability in CI users prompts the need for more objective measures of speech perception performance. Electrophysiological metrics of CI performance may be an important tool for audiologists in the assessment of hearing rehabilitation. Utilizing electroencephalography (EEG), it may be possible to evaluate speech perception correlates such as spectral discrimination. The mismatch negativity (MMN) of 10 CI subjects was recorded for stimuli containing different spectral densities. The neural spectral discrimination threshold, estimated by the MMN responses, showed a significant correlation with the behavioral spectral discrimination threshold measured in each subject. Results suggest that the MMN can be potentially used to obtain an objective estimate of spectral discrimination abilities in CI users.

Surface biotechnology for refining cochlear implants.

The advent of the cochlear implant is phenomenal because it is the first surgical prosthesis that is capable of restoring one of the senses. The subsequent rapid evolution of cochlear implants through increasing complexity and functionality has been synchronized with the recent advancements in biotechnology. Surface biotechnology has refined cochlear implants by directly influencing the implant­tissue interface. Emerging surface biotechnology strategies are exemplified by nanofibrous polymeric materials, topographical surface modification, conducting polymer coatings, and neurotrophin-eluting implants. Although these novel developments have received individual attention in the recent literature, the time has come to investigate their collective applications to cochlear implants to restore lost hearing.

Synovial cell sarcoma of the larynx.

Synovial cell sarcoma represents a rare group of cancers, particularly in the head and neck region, that typically affects young individuals and has a male preponderance. Prognosis varies with patient age, site and size of the malignancy, degree of necrosis, high level of mitotic activity, and neurovascular invasion. Complete surgical resection of the tumor via partial or total laryngectomy is the first-line treatment in locally invasive disease. CO(2) lasers have been shown to be useful in controlling localized disease. There is also a role for adjuvant radiotherapy. Ifosfamide-based chemotherapy is most useful for malignant disease.

Use of an intra-operative nerve stimulator in identifying the hypoglossal nerve.

Previously, the hypoglossal nerve has not undergone intra-operative monitoring during neck operations in which the nerve is at risk. As society becomes increasingly litigious, this may change. This study describes the technique and the microvoltages used in 10 patients for intra-operative stimulation of the hypoglossal nerve with the Magstim nerve stimulator. We confirm that the technique is possible, simple and safe, with minimal disturbance to the patient, anaesthetist and surgeon.