Management of Severe Facial Nerve Cross Stimulation by Cochlear Implant Replacement to Change Pulse Shape and Grounding Configuration: A Case-series.

OBJECTIVES: To investigate the combined effect of changing pulse shape and grounding configuration to manage facial nerve stimulation (FNS) in cochlear implant (CI) recipients. PATIENTS: Three adult CI recipients with severe FNS were offered a replacement implant when standard stimulation strategies and programming adjustments did not resolve symptoms. Our hypothesis was that the facial nerve was less likely to be activated when using anodic pulses with "mixed-mode" intra-cochlear and extra-cochlear current return. INTERVENTION: All patients were reimplanted with an implant that uses a pseudo-monophasic anodic pulse shape, with mixed-mode grounding (stimulus mixed-mode anodic)-the Neuro Zti CI (Oticon Medical). This device also allows measurements of neural function and loudness with monopolar, symmetric biphasic pulses (stimulus MB), the clinical standard used by most CIs as a comparison. MAIN OUTCOME MEASURES: The combined effect of pulse shape and grounding configuration on FNS was monitored during surgery. Following CI activation, FNS symptoms and performance with the Neuro Zti implant were compared with outcomes before reimplantation. RESULTS: FNS could only be recorded using stimulus MB for all patients. In clinical use, all patients reported reduced FNS and showed an improvement in Bamford-Kowal-Bench sentences recognition compared with immediately before reimplantation. Bamford-Kowal-Bench scores with a male speaker were lower compared with measurements taken before the onset of severe FNS for patients 1 and 2. CONCLUSIONS: In patients where CI auditory performance was severely limited by FNS, charge-balanced pseudo-monophasic stimulation mode with a mixed-mode grounding configuration limited FNS and improved loudness percept compared with standard biphasic stimulation with monopolar grounding.

The Epidemiology of Otosclerosis in a British Cohort.

OBJECTIVE: To analyse the epidemiology of otosclerosis in a British cohort collected between 2011 and 2017. DESIGN: Retrospective cohort study. SETTING: Five UK ENT Departments. PATIENTS: Patients with surgically confirmed otosclerosis. MAIN OUTCOME MEASURES: Questionnaire data documented family history of otosclerosis, age of onset, medical history, and information on associated risk factors for 657 patients. Pre and post-surgical pure-tone audiometry was collected for 154 of these patients. RESULTS: The age of onset, incidence of bilateral disease, tinnitus and vertigo, a higher prevalence of women (65%) than men (35%) are similar to those reported previously for otosclerosis cohorts. No association with measles infection was detected. Patients with a family history (40%) have an earlier age of onset and a higher incidence of bilateral disease and vertigo than non-familial subjects. Pedigree analysis is consistent with an autosomal dominant inheritance with reduced penetrance being apparent in 44/91 pedigrees studied. Women who associate their hearing loss with pregnancy have an earlier age of onset than those that do not (p = 6 × 10). CONCLUSIONS: This study confirms that otosclerosis is an early adult onset disease that is more prevalent in women than men with a large minority of patients having a family history of otosclerosis. We report new evidence to support a relationship between pregnancy and otosclerosis progression in a proportion of women. In addition, this is the first study to identify differences in severity between familial and non-familial cases of otosclerosis, highlighting the possibility that more than one etiology may be involved.

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.

Outcomes of Transmastoid Surgery for Superior Semicircular Canal Dehiscence Syndrome.

OBJECTIVE: To present the management strategy and outcomes for our series of superior semicircular canal dehiscence syndrome (SSCDS) patients. STUDY DESIGN: Retrospective cross-sectional study. SETTING: Tertiary referral center. PATIENTS: Thirty-seven consecutive patients referred from June 2011 to January 2015. Diagnosis of SSCDS based on presence of classical symptoms, computerized tomography, and concordant reduction in cervical vestibular evoked myogenic potentials. INTERVENTIONS: Transmastoid resurfacing or plugging. MAIN OUTCOME MEASURES: Pre- and postoperative pure tone audiometry. Nine item questionnaire grading pre- and postoperative symptom severity. Results of a short semi-structured telephone survey. RESULTS: Twenty surgical patients: 13 women and 7 men. Mean age 52 years 6 months. Eighteen patients underwent transmastoid resurfacing and two underwent transmastoid plugging. Three of those who initially had resurfacing but had ongoing SSCD symptoms, subsequently had transmastoid plugging with complete resolution of third window symptoms. From the questionnaire there was improvement in mean scores for 8 of 9 of the SSCD symptoms, with statistically significant improvement in 6 of 9. CONCLUSIONS: Management strategies and surgical techniques continue to evolve for SSCDS. We currently offer transmastoid resurfacing having informed patients of a 25% possibility of incomplete symptom resolution, and explain that plugging can be performed as a "second stage," if necessary. However, as we accrue more experience and there is more evidence from the literature we are considering whether to offer transmastoid plugging as our primary surgical procedure. In our experience, patients with multiple vestibular pathologies or atypical vestibular symptoms are the ones for whom SSCD surgery has not been curative, although they do report improvement in their SSCD symptoms.

Cochlear implantation in X-linked deafness - How to manage the surgical challenges.

OBJECTIVE AND IMPORTANCE: In children with X-linked deafness, cochlear malformations challenge the implant surgeon to avoid electrode insertion into the internal auditory meatus and prevent a continuous cerebrospinal fluid (CSF) leak. We describe our experience of cochlear implantation (CI) in two children with profound hearing loss secondary to X-linked deafness, highlighting safer operative techniques to avoid potential complications. CLINICAL PRESENTATION: Descriptive cases of two children with X-linked deafness (patient 1 and patient 2) undergoing CI. Peri-operative imaging and work-up to surgery are discussed. Specific operative considerations, post-operative complications and subsequent audiological performance are highlighted. TECHNIQUE: In each case, intra-operative fluoroscopic imaging ensured intra-cochlear insertion of electrodes. Expected CSF gusher was seen in each case which was initially controlled by packing around the cochleostomy and array with temporalis muscle and fascia. Patient 1 developed post-operative meningitis secondary to continuous CSF leak. We avoided further significant CSF leak by planning staged procedures for patient 2, with obliteration of the middle ear cleft and external ear canal (EAC) at the time of implantation. In both patients, bilateral implantation successfully provided hearing thresholds of less than 35 dB in both ears at routine follow up. CONCLUSIONS: When planning for CI in children with radiological features of X-linked deafness, intra-operative imaging should be utilized to ensure correct electrode positioning. Traditional methods of stopping a CSF gusher may not suffice. We therefore encourage additional surgical obliteration of the middle ear space and EAC to avoid persistent CSF leak and its associated complications.

Mutations and altered expression of SERPINF1 in patients with familial otosclerosis.

Otosclerosis is a relatively common heterogenous condition, characterized by abnormal bone remodelling in the otic capsule leading to fixation of the stapedial footplate and an associated conductive hearing loss. Although familial linkage and candidate gene association studies have been performed in recent years, little progress has been made in identifying disease-causing genes. Here, we used whole-exome sequencing in four families exhibiting dominantly inherited otosclerosis to identify 23 candidate variants (reduced to 9 after segregation analysis) for further investigation in a secondary cohort of 84 familial cases. Multiple mutations were found in the SERPINF1 (Serpin Peptidase Inhibitor, Clade F) gene which encodes PEDF (pigment epithelium-derived factor), a potent inhibitor of angiogenesis and known regulator of bone density. Six rare heterozygous SERPINF1 variants were found in seven patients in our familial otosclerosis cohort; three are missense mutations predicted to be deleterious to protein function. The other three variants are all located in the 5'-untranslated region (UTR) of an alternative spliced transcript SERPINF1-012 RNA-seq analysis demonstrated that this is the major SERPINF1 transcript in human stapes bone. Analysis of stapes from two patients with the 5'-UTR mutations showed that they had reduced expression of SERPINF1-012 All three 5'-UTR mutations are predicted to occur within transcription factor binding sites and reporter gene assays confirmed that they affect gene expression levels. Furthermore, RT-qPCR analysis of stapes bone cDNA showed that SERPINF1-012 expression is reduced in otosclerosis patients with and without SERPINF1 mutations, suggesting that it may be a common pathogenic pathway in the disease.

Cochlear Implant Outcomes in Cochlea Nerve Aplasia and Hypoplasia.

OBJECTIVE: To assess cochlear implant (CI) outcomes, and factors affecting outcomes, for children with aplasia/ hypoplasia of the cochlea nerve. We also developed a new grading system for the nerves of the internal auditory meatus (IAM) and cochlea nerve classification. STUDY DESIGN: Retrospective patient review. SETTING: Tertiary referral hospital and cochlear implant program. PATIENTS: Children 0 to 16 years inclusive with a CI who had absent/hypoplastic cochlea nerve on magnetic resonance imaging (MRI). INTERVENTION: Cochlear implant. MAIN OUTCOME MEASURES: MRI, trans-tympanic electrical auditory brainstem response, intraoperative electrical auditory brainstem response, Neural Response Telemetry, Categories of Auditory Perception score, Main mode of communication. RESULTS: Fifty CI recipients (26 males and 24 females) were identified, 21 had bilateral CIs, 27 had developmental delay. MRI showed cochlea nerve aplasia in 64 ears, hypoplasia in 25 ears, and a normal nerve in 11 ears. Main mode of communication was analyzed for 41 children: 21 (51%) used verbal language (15 speech alone, 5 speech plus some sign, 1 bilingual in speech and sign), and 20 (49%) used sign language (10 sign alone, 9 sign plus some speech, 1 tactile sign). Seventy-three percent of children used some verbal language. Cochlea nerve aplasia/ hypoplasia and developmental delay were both significant factors affecting main mode of communication. Categories of Auditory Performance scores were available for 59 CI ears; 47% with CN Aplasia (IAM nerve grades 0-III) and 89% with CN hypoplasia (IAM nerve grade IV) achieved Categories of Auditory Performance scores of 5 to 7 (some verbal understanding) (p = 0.003). CONCLUSION: Our results are encouraging and useful when counselling families regarding the likelihood of language outcomes and auditory understanding.

A Comparative Study of Audiologic Outcomes for Two Transcutaneous Bone-Anchored Hearing Devices.

OBJECTIVE: In 1977, Tjellstrom et al. used the concept of osseointegration and implanted patients with a titanium screw as part of the first bone-anchored hearing solution. Despite good hearing outcomes with the percutaneous device, there has been a drive for the development of transcutaneous bone conduction systems because of soft tissue complications, aesthetics, and loss or failure of the abutment. This study compares audiologic and quality of life questionnaire outcomes (author-designed questionnaire) for two transcutaneous bone conduction implants. STUDY DESIGN: Cross-sectional cohort study. SETTING: Tertiary referral hospital and national audiology service. PATIENTS: Twelve patients, 10 children and two adults. Six recipients of each device. MAIN OUTCOME MEASURES: Pure-tone audiometry, aided thresholds, speech discrimination scores, and quality of life questionnaire results. RESULTS: The unaided four-frequency average air conduction for affected ears was 60.8 dB HL for the Attract group and 57.8 dBHL for the Sophono group; these improved to mean aided thresholds of 30.6 dB HL and 29.8 dB HL, respectively. Therewas no statistical difference between the speech discrimination scores for the two devices in quiet at 55 dB SPL (p = 0.33) orin noise (p = 0.87). CONCLUSION: Both systems provide audiologic benefit compared with the unaided situation. Comparing small numbers of patients, there was no significant difference in aided thresholds or speech discrimination scores between these two transcutaneous bone-anchored implants. All Attract and Sophono users reported improvement in quality of life and would recommend their device to others in a similar situation.

Large vestibular aqueduct syndrome: Impedance changes over time with different cochlear implant electrode arrays.

OBJECTIVES: The aim of this study was to assess if large vestibular aqueduct syndrome (LVAS), with the increase in perilymphatic pressure, affects impedance changes over time with different types of Cochlear(®) implant electrode arrays Contour, Straight, and CI 422. To report speech perception outcomes for these cochlear implant recipients. METHODS: Retrospective case review of impedance levels and categories of auditory performance. Impedance data were collected at switch on, 1 month, 3, 6, 12, and 24 months after cochlear implantation and compared with control (non-LVAS cochlear implant recipient) data for each array type. Forty-seven patients with exclusive LVAS and no other vestibulocochlear abnormalities or other identifiable cause of deafness were eligible for inclusion in the study. RESULTS: In LVAS patients, there was a significant difference in impedance between the three types of device (P < 0.0001). Time since switch on was associated with a decrease in impedance for all three devices (P < 0.0001). The mean impedance reduced between switch on and 1 month and remained relatively constant thereafter. Sound variation with softening of sounds was seen in four CI 422 (Straight Research Array) recipients due to ongoing fluctuations in electrode compliance. DISCUSSION: For all three array types, there was no significant difference in the mean impedance between the LVAS patients and controls over the first 12 months. In keeping with previous studies cochlear implant recipients with LVAS hear very well through the cochlear implant.

Cochlear re-implant rates in children: 20 years experience in a quaternary paediatric cochlear implant centre.

The aim of this study is to determine the incidence and causes for cochlear explantation/re-implantation in children as a retrospective case review in a Quaternary paediatric Cochlear Implant (CI) Centre. The subjects included in the study were Paediatric CI patients requiring cochlear explantation/re-implantation. Outcome measurements were incidence and aetiology of device explantation/re-implantation. Patient age at implantation, aetiology of deafness, CI manufacturer, and timing of explantation/re P implantation were the independent variables. 778 paediatric cochlear implants were performed in 653 children between 1992 and January 2013. There were a total of 40 (5.1%) failed implants in 38 patients. The most common reason for explantation was device failure in 22 (2.8%). Risk factors for device failure were known manufacturing defect/device recall. Medical/surgical issues accounted for 18 (2.3%) implant failures. The mean time to explantation was 3 years 10 months. The incidence of explantation/re-implantation in our paediatric cochlear implant population is comparable to other published studies. The most common reason for explantation was device failure, however, the aetiology of deafness, in particular meningitis, does not appear to increase the risk of explantation as described in previous series.

Resorption of fibula bone following mandibular reconstruction for osteoradionecrosis.

The free fibular flap is commonly used for mandibular reconstruction because of its length, consistent blood supply, and relative ease of harvest. The bone has been shown to maintain mass over time, which confers a potential advantage over other osseous flaps. We know of no published papers on changes in height of fibular bone in patients treated for osteoradionecrosis (ORN). We measured the change in bony height over time as an indirect measure of bone mass. We identified 17 patients (mean age 65, range 49-80 years) who had had reconstruction with a free fibular flap for mandibular ORN. Of them, 10 had fixation with a reconstruction plate, and serial radiographs were available for inclusion in the study. Three measurements were taken on at least 2 rotational tomograms for each patient. Two observers recorded measurements at 25, 50, and 75% of the distance along the bone. Mean change in fibular height (mm) and percentage change were calculated. The interval between radiographs ranged from 5 months 4 days to 20 months 14 days. There was a reduction in fibular height in 8/10 cases, with a mean reduction of 1.5mm (range 2.6-0.3), or 11%. Our results show a moderate reduction in fibular height, which is comparable with a previously published series of patients without ORN who had reconstruction with miniplates. The stress shielding effects of reconstruction plates were less evident in our patients than in previously published material.

Improved quality of life in adults undergoing tonsillectomy for recurrent tonsillitis. Is adult tonsillectomy really a low priority treatment?

There is a paucity of studies on patient-reported outcome measures in adult tonsillectomy. Our aim was to add to the body of health-related quality of life (HRQOL) evidence on adult tonsillectomy at a time when this intervention is being branded a low priority treatment in the United Kingdom (UK). We designed a prospective questionnaire study that was carried out in two UK district general hospitals. 41 patients were recruited into the study and completed a pre-operative short form 36 questionnaire. All 41 were contacted at least 1 year after tonsillectomy and were asked to complete the same SF-36 questionnaire and three additional HRQOL questions. There was a significant improvement in quality of life shown by both the mean SF-36 scores and the HRQOL questions. The SF-36 summary measures and the total SF-36 scores improved significantly (p < 0.01). The study emphasises the importance of tonsillectomy being available on the National Health Service to adults with recurrent tonsillitis. This proven quality of life improvement is also highly likely to confer a secondary health economic benefit from less GP attendances and fewer missed work days.

Day-case pediatric middle ear surgery: from myringoplasty to bilateral cochlear implantation.

OBJECTIVE: In the English speaking literature there is very little evidence demonstrating safe and effective tympanomastoid day case surgery in pediatric practice. At a time when there is ongoing pressure for trusts to meet financial government targets and our care provision revolves around a patient centred approach, could otolaryngologists perform more pediatric middle ear surgery on a day case basis? We report our experience with a series of 52 pediatric middle ear day cases. METHOD: Prospective study from a London tertiary referral centre of 52 consecutive children undergoing tympanomastoid surgery. There were 6 categories of surgical procedure, ranging from myringoplasty to cochlear implantation. Post-operative recovery was monitored. The duration of anaesthesia was compared with the length of post-operative ward stay. RESULTS: The correlation co-efficient r=-0.2203, showing that there was no association between length of anaesthetic and duration of post-operative ward stay. CONCLUSIONS: Despite minor post-operative problems including pain, bleeding, and nausea and vomiting all patients in this series were discharged on the day of surgery. For tympanoplasty our series adds weight to already available evidence. It is the first series showing that mastoid surgery, whether combined approach, traditional mastoidectomy or cochlear implantation can be performed safely as day cases in a pediatric population.

Should all patients referred for magnetic resonance imaging scans of their internal auditory meatus be followed up in ENT clinics?

Magnetic resonance imaging (MRI) is recognised as the "Gold Standard" investigation for symptoms pertaining to the inner ear and detection of retro-cochlear pathology. There is still no accurate clinical predictor for cerebellopontine angle lesions and increasingly more normal scans are being performed. With constantly increasing demands on ENT outpatient clinics, our aim was to investigate whether all patients referred for MRI of their internal auditory meatus (IAM) require follow-up in ENT clinics. A retrospective study was carried out in a tertiary referral centre referring patients for MRI IAM from ENT clinics and neurotology clinics on 153 patients referred for MRI IAM performed over a 4-month period. The MRI reports and the case notes of the patients were reviewed. MRI results and patient symptoms with patient follow-up schedule and follow-up situation for at least 6 months post-scan were compared. There were two patient groups, those referred from main outpatients (81) and those referred by the audiological physicians (72). Of the total number of scans, 101 were reported as normal, 45 had incidental findings, and 7 showed pathology of the cerebellopontine angle. The presenting complaints of the patients, the scan results and the follow-up since were compared. Six months later 63% of those referred from outpatients were no longer being followed up in clinic. We suggest that 56.8% of patients referred for MRI IAM do not require ENT follow-up. Their symptoms and concerns could be dealt with at the first consultation where onward referral could be made if necessary. Once checked by the requesting clinician, uncomplicated scan results could be sent to the patients and general practitioners by post or email. This would reduce the burden on general otolaryngology outpatient clinics and improve resource utilisation.