Faculty Bibliography

OBJECTIVE:To describe the natural history of primary inner ear schwannomas over a long follow-up period. STUDY DESIGN/METHODS:Retrospective case series. SETTING/METHODS:Tertiary referral center. PATIENTS/METHODS:Patients with primary inner ear schwannomas with serial audiometric and radiologic follow-up. MAIN OUTCOME MEASURES/METHODS:Patterns of hearing loss, rate of hearing decline, presence of vestibular symptoms, and rate of tumor growth. RESULTS:A total of 12 patients with 13 tumors were identified. The mean duration of follow-up was 7 years. Forty-six percent of tumors were intracochlear, 15% were intravestibular, 23% were transmodiolar, and 15% were intravestibular-cochlear. Hearing loss was the most common presenting symptom, occurring in all patients. Among patients with serviceable hearing (AAO Class A or B) at the time of presentation, the average time to decline to a nonserviceable hearing level was 57.3 months (range, 21-117 mo). Hearing loss was sudden in 31% of patients, progressive in 61% and fluctuating in 8%. No patients had intractable vertigo; however, two required vestibular physiotherapy. On initial magnetic resonance imaging, the mean largest tumor dimension was 3.1 mm (standard deviation, 1.2 mm), and the mean largest dimension on most recent magnetic resonance imaging was 4.4 mm (standard deviation, 1.1 mm). Two tumors exhibited no growth over a follow-up of 11.3 and 2.8 years, respectively. Overall, the mean growth was 0.25 mm per year followed. Two patients underwent cochlear implantation with simultaneous tumor resection and had favorable outcomes. CONCLUSION/CONCLUSIONS:Long-term follow-up suggests a conservative approach, with possible hearing rehabilitation at the time of deterioration, is a safe management strategy for primary inner ear schwannomas.

OBJECTIVE/UNASSIGNED:Evaluate rates of Advanced Bionics Ultra 3D/Ultra cochlear implant failure in the setting of a worldwide device recall and report surgical and auditory outcomes after revision. METHODS/UNASSIGNED:Retrospective chart review was performed for adult and pediatric patients implanted with at risk devices at our center from 2016 to 2020. Device failure rates, surgical, and auditory outcomes were recorded and analyzed. RESULTS/UNASSIGNED: = 0.95). DISCUSSION/UNASSIGNED:Patients with device failure due to this field action performed well after revision implantation. Patients with bilateral at-risk devices but evidence of unilateral failure may elect to undergo simultaneous empiric revision of the contralateral device. Three patients who elected to change device manufacturers on revision have variable results that require further investigation. CONCLUSIONS/UNASSIGNED:Patients requiring revision for a device field action overall perform well. At-risk devices continue to require monitoring as a growing number are likely to fail over time.

OBJECTIVE:To review the current literature regarding cochlear implantation in patients with retrocochlear pathologies and extract speech perception scores between 6 months and 1 year after surgery. DATABASES REVIEWED/UNASSIGNED:PubMed/MEDLINE, Embase and Cochrane CENTRAL via Ovid, CINAHL Complete via Ebsco, and Web of Science. METHODS:The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Search strategies included keywords and subject headings to maximize retrieval and reflect cochlear implants and retrocochlear pathologies. Patients with previously resected vestibular schwannoma (VS) were excluded. RESULTS:There were 2,524 abstracts screened against inclusion criteria, and 53 studies were included, with individual data available for 171 adult patients. Pathologies included were either observed or irradiated VS (previously operated tumors were excluded) (n = 99, 57.9%), superficial siderosis (n = 39, 22.8%), neurosarcoidosis (n = 11, 6.4%), and previous central nervous system or skull base radiation (n = 22, 12.9%). Mean (standard deviation) postoperative consonant-nucleus-consonant (CNC) word scores were 45.4% (24.2) for observed VS, 44.4% (20.8) for irradiated VS, 43.6% (21.0) for superficial siderosis, 89.5% (3.0) for neurosarcoidosis, and 30.0% (30.2) in patients with previous central nervous system or skull base irradiation. Irradiated compared with observed VS had similar postoperative CNC word scores (effect size, 0.06; p = 0.71). Age, sex, maximal tumor dimension, and neurofibromatosis type 2 status did not significantly impact cochlear implant performance in patients with VS. Eighty-two percent of patients with reported device usage were daily users, and overall, 82% of cases benefitted from cochlear implantation. CONCLUSION/CONCLUSIONS:Cochlear implantation in patients with concomitant retrocochlear pathology generally results in improved speech discrimination scores sustained over time.

OBJECTIVE:To evaluate the ability of the transimpedance matrix (TIM) measurement to detect cochlear implant electrode tip foldover by comparing results to a "gold standard," the intraoperative plain film radiograph. STUDY DESIGN/METHODS:Retrospective case series. SETTING/METHODS:Tertiary referral hospital. PATIENTS/METHODS:One hundred three patients who underwent cochlear implantation between June 2020 and August 2021. INTERVENTIONS/METHODS:Intraoperative electrophysiologic monitoring (electrode impedances, neural response telemetry, and TIM measurement) and modified Stenver's view plain film radiographs. MAIN OUTCOME MEASURES/METHODS:Identification of tip foldover on both TIM and plain films. RESULTS:In total, 103 patients (117 ears) had both a TIM measurement and intraoperative X-ray available for review, including 68 adults and 35 children. One hundred patients (85%) received the Cochlear Slim Modiolar electrode. Tip foldovers were noted in three of 117 implants (2.5%). In all cases, TIM was able to detect the foldover, and the electrode arrays were reinserted with the patients still under anesthesia, with repeat X-ray demonstrating a normal configuration. Two other abnormal TIM patterns were identified. One was in a patient with an obstructed cochlea in whom only 10 electrodes could be inserted, the other was in a patient with a common cavity abnormality. One additional patient underwent electrode repositioning intraoperatively because of overinsertion. In this patient, the TIM appeared to be within normal limits, but the over-insertion was apparent on X-ray. Overall, the sensitivity and specificity of TIM measurements in detecting electrode tip foldover were both 100%. CONCLUSION/CONCLUSIONS:TIM measurements were able to accurately identify tip foldovers. More research is needed to define the adjunctive role of TIM as an intraoperative measure.

BACKGROUND:For patients with vestibular schwannoma (VS), stereotactic radiosurgery (SRS) has proven effective in controlling tumor growth while hearing preservation remains a key goal. OBJECTIVE:To evaluate hearing outcomes in the modern era of cochlear dose restriction. METHODS:During the years 2013 to 2018, 353 patients underwent Gamma knife surgery for VS at our institution. We followed 175 patients with pre-SRS serviceable hearing (Gardner-Robertson Score, GR 1 and 2). Volumetric and dosimetry data were collected, including biological effective dose, integral doses of total and intracanalicular tumor components, and hearing outcomes. RESULTS:The mean age was 56 years, 74 patients (42%) had a baseline GR of 2, and the mean cochlear dose was 3.5 Gy. The time to serviceable hearing loss (GR 3-4) was 38 months (95% CI 26-46), with 77% and 62% hearing preservation in the first and second years, respectively. Patients optimal for best hearing outcomes were younger than 58 years with a baseline GR of 1, free canal space ≥0.041 cc (diameter of 4.5 mm), and mean cochlear dose <3.1 Gy. For such patients, hearing preservation rates were 92% by 12 months and 81% by 2 years, staying stable for >5 years post-SRS, significantly higher than the rest of the population. CONCLUSION/CONCLUSIONS:Hearing preservation after SRS for patients with VS with serviceable hearing is correlated to the specific baseline GR score (1 or 2), age, cochlear dose, and biological effective dose. Increased tumor-free canal space correlates with better outcomes. The most durable hearing preservation correlates with factors commonly associated with smaller tumors away from the cochlea.

This "How I Do It" report describes modifications made to the OSIA bone conduction hearing implant surgery in order to reduce wound complications. Laryngoscope, 2022.

OBJECTIVE:To evaluate outcomes of auditory implants in children with CHARGE syndrome and describe the evolution in management of hearing loss in this complex population. METHODS:A retrospective case review was performed at a tertiary referral center. Children with CHARGE syndrome who received either a cochlear implant (CI) or auditory brainstem implant (ABI) were included. Clinical records, demographic information, CHARGE features, neuroimaging, audiology, hearing rehabilitation interventions, operative notes, and outcomes were reviewed. RESULTS:Thirteen children with CHARGE syndrome underwent a total of 19 cochlear implants between 2008 and 2020. Among the congenitally deafened children (n = 9), six underwent bilateral implantation (five simultaneous and one sequential). Bilateral implantation was performed even in the presence of diminutive-appearing cochlear nerves. The average age of implantation was 1.1 years, and the mean device use time was 9.4 hours per day. Patients showed improvements in subjective family assessment related to hearing. In this group, two patients use oral communication, five use total communication, and two use sign language exclusively. Among the children with progressive hearing loss, the mean age of hearing deterioration was 4.4 years of age, and the device use time on average was 9.8 hours per day. The highest performer in the cohort was a child who lost hearing in their only hearing ear at age 4 and had normal cochleovestibular anatomy on that side. One child received an auditory brainstem implant at age two after deriving no benefit from a CI and can detect environmental sounds but is currently a nonuser. Over time, we noted that implantation occurred earlier in life and that practice has shifted toward bilateral implantation. CONCLUSIONS:Compared to a previous institutional cohort, children evaluated in this study were often implanted at a younger age and bilaterally with significantly improved outcomes. A CI evaluation should be considered in children with CHARGE syndrome to maximize sensory input and auditory ability.

PURPOSE/OBJECTIVE:Severe hearing loss is particularly prevalent among Veterans. In response, the Veterans Affairs (VA) provides hearing aids and cochlear implants as part of their comprehensive hearing loss treatment. The VA's national health care system and integrated electronic health records offer a unique opportunity to examine patterns and outcomes in the management of severe hearing loss. METHOD/METHODS:We retrospectively reviewed an urban VA center's database for all Veterans who underwent cochlear implantation between 2010 and 2019. We collected preoperative demographic and audiological data including cochlear implant outcomes. RESULTS:During the study period, 61 Veterans received a cochlear implant, totaling 70 ears implanted. Median age at implantation was 70.2 years. Over 90% of Veterans reported preoperative hearing aid use, and median preoperative four-frequency pure-tone average and aided word recognition score in the ear to be implanted were 100 dB HL and 7%, respectively. The median onset of severe hearing loss bilaterally was over 4 years prior to cochlear implant evaluation based on available audiometric data. Postoperative word recognition score was negatively correlated with self-reported duration of hearing loss. CONCLUSIONS:This study provides unique insights into how Veterans with severe hearing loss are managed at one VA center. Compared to data published on cochlear implant recipients in the civilian population, Veterans in this cohort were older and had higher rates of preoperative hearing aid use. Available VA data suggest most Veterans were appropriate candidates for cochlear implant referral years prior to undergoing an evaluation. Reasons for treatment delays in this population remain to be studied.

OBJECTIVE:To investigate a new surgical and signal processing technique that provides apical stimulation of the cochlea using a cochlear implant without extending the length of the electrode array. PATIENTS/METHODS:Three adult patients who underwent cochlear implantation using this new technique. INTERVENTIONS/METHODS:The patients received a cochlear implant. The surgery differed from the standard approach in that a ground electrode was placed in the cochlear helicotrema via an apical cochleostomy rather than in its typical location underneath the temporalis muscle. Clinical fitting was modified such that low frequencies were represented using the apically placed electrode as a ground. MAIN OUTCOME MEASURES/METHODS:Pitch scaling and speech recognition. RESULTS:All surgeries were successful with no complications. Pitch scaling demonstrated that use of the apically placed electrode as a ground lowered the perceived pitch of electric stimulation relative to monopolar stimulation. Speech understanding was improved compared with preoperative scores. CONCLUSIONS:The new surgical approach and clinical fitting are feasible. A lower pitch is perceived when using the apically placed electrode as a ground relative to stimulation using an extracochlear ground (i.e., monopolar mode), suggesting that stimulation can be provided more apically without the use of a longer electrode array. Further work is required to determine potential improvements in outcomes and optimal signal processing for the new approach.

OBJECTIVES/OBJECTIVE:Age of cochlear implantation (CI) is an important predictor of language development in those with congenital sensorineural hearing loss. Despite universal newborn hearing screening initiatives and the known benefits of early CI, a subset of congenitally deaf children continue to be evaluated for cochlear implants later in childhood. This study aims to identify the barriers to early cochlear implantation in these children. METHODS:A retrospective review was conducted for all pediatric cochlear implants aged 3 years or older performed at a single academic institution between 2013 and 2017. Children implanted before the age three, those with a prior unilateral cochlear implant, and those with progressive or sudden hearing loss were excluded. Variables included newborn hearing screen results, age at hearing loss diagnosis, time of initiation and documented benefit of hearing aids, age of implantation, pre/post-implantation evaluation scores, and reason for delayed referral for cochlear implantation. RESULTS:Thirty-one patients were identified meeting these inclusion criteria. Twenty-one children were subject to UNBS in the U.S. Fourteen of those children failed their newborn hearing screening. Average age at implantation was 6.2 years. Four reasons were identified for increased age at cochlear implantation. Two categories represent delays related to (1) Amplification continually prescribed even though the range of hearing loss and speech development assessment suggests CI may have been more appropriate well before referral (N = 13) (2) Patients were not subject to newborn hearing screening and/or timely diagnosis of their hearing loss (N = 8). In other cases, patients were appropriately fit with hearing aids until evidence that they derived limited benefit and then referred for CI (N = 8). Lastly, in a few cases, records were indeterminate with regards to the timing and appropriate diagnosis of their hearing loss (N = 2). CONCLUSION/CONCLUSIONS:Understanding the reasons for delayed cochlear implantation in congenitally deaf children might allow the development of targeted interventions to improve outcomes. Specifically, those children who were not referred before age 3 despite use of amplification with limited benefit offer one potential target population for earlier CI.