Faculty Bibliography

OBJECTIVES:Immune-checkpoint inhibitors (ICI) are being utilized with increasing frequency and may be linked to neurologic and audiovestibular toxicities. This report aimed to describe a case of ICI-induced sensorineural hearing loss ultimately requiring bilateral cochlear implantation. METHODS:A 42-year-old female with stage IV metastatic melanoma of the perianal skin was treated with ipilimumab (blocker of cytotoxic T-lymphocyte associated protein 4 [CTLA-4]) and nivolumab (anti-programmed cell death protein 1 [PD1]). After 21 weeks of therapy, she developed sudden vertigo and bilateral hearing loss. A full workup including MRI and lumbar puncture ruled out intracranial parenchymal metastases, leptomeningeal metastases, stroke and intracranial infection. ICI-associated aseptic meningoencephalitis was therefore diagnosed. The patient received systemic steroids as well as intratympanic steroids, which temporarily improved hearing, but eventually developed permanent, bilateral profound sensorineural hearing loss. RESULTS:The patient received bilateral cochlear implants and has demonstrated good performance one year after implantation. DISCUSSION:ICI are being increasingly used to treat a variety of advanced malignancies. This is the first report of bilateral cochlear implants in the context of profound hearing loss after an immunotherapy induced meningoencephalitis. CONCLUSION:ICI carries the risk of potential ototoxicity, including profound SNHL as depicted in our case. Cochlear implantation proved to be beneficial and may be considered in patients with ICI-related hearing loss.

OBJECTIVE:Children with high-frequency severe-to-profound hearing loss and low-frequency residual hearing who do not derive significant benefit from hearing aids are now being considered for cochlear implantation. Previous research shows that hearing preservation is possible and may be desirable for the use of electroacoustic stimulation (EAS) in adults, but this topic remains underexplored in children. The goal of this study was to explore factors relating to hearing preservation, acceptance, and benefits of EAS for children. STUDY DESIGN:Retrospective review. SETTING:Tertiary academic medical center. PATIENTS:Forty children (48 ears) with preoperative low-frequency pure-tone averages of 75 dB HL or less at 250 and 500 Hz (n = 48). INTERVENTION:All patients underwent cochlear implantation with a standard-length electrode. MAIN OUTCOME MEASURE:Low-frequency audiometric thresholds, speech perception, and EAS usage were measured at initial stimulation, and 3 and 12 months postoperatively. Outcomes were compared between children with and without hearing preservation, and between EAS users and nonusers. RESULTS:Hearing was preserved at similar rates as adults but worse for children with an enlarged vestibular aqueduct. Fewer than half of children who qualified to use EAS chose to do so, citing a variety of audiologic and nonaudiologic reasons. No differences were detected in speech perception scores across the groups for words, sentences, or sentences in noise tests. CONCLUSIONS:Neither hearing preservation nor EAS use resulted in superior speech perception in children with preoperative residual hearing; rather, all children performed well after implantation.

OBJECTIVES:To determine rates of hearing preservation and performance in patients who met candidacy for electroacoustic stimulation (EAS) and were implanted with a slim modiolar electrode (CI532 or CI632). DESIGN:Adult patients meeting Food and Drug Administration criteria for electroacoustic stimulation (preoperative low-frequency pure-tone average [LFPTA] less than 60 dB at 125, 250, and 500 Hz and monosyllabic word scores between 10% and 60% in the ear to be implanted), who received a slim modiolar electrode were included. Main outcome measures included rates of hearing preservation, defined as a LFPTA ≤80 dB at 125, 250, and 500 Hz, as well as postoperative low-frequency pure-tone threshold shifts, consonant-Nucleus-Consonant (CNC) word scores and AzBio sentences in noise scores. RESULTS:Forty-six patients met inclusion criteria during a 4-year period. Mean (standard deviation) preoperative LFPTA was 34.5 (13.0) dB, and 71.7% had preserved hearing at initial activation. The mean LFPTA shift in patients who preserved hearing at initial activation was 19.7 (14.6) dB, compared with 62.6 (17.7) dB in patients who did not preserve hearing as per our definition. Perioperative steroid use was not different in patients with and without preserved hearing (X 2 (1, N = 46) = 0.19, p = .67, V = 0.06). One year after surgery, 57% of patients had a decline in LFPTA >80 dB and were no longer considered candidates for EAS, with 34.7% still retaining low-frequency thresholds ≤80 dB. CNC word scores at 1 year were 69.9% and 61.4% among individuals with and without preserved low-frequency hearing respectively, measured in their CI ear alone, in their regular listening condition of EAS or electric only ( t (32) = 1.13, p = 0.27, d = 0.39, 95% CI = -6.51, 22.86). Device use time did not differ between groups. Among adults with preserved residual hearing at 1 year (n = 16), 44% used EAS, although there was no significant difference in performance between EAS users and nonusers with preserved hearing. Loss of residual hearing over time did not result in a decline in speech perception performance. CONCLUSION:The present study demonstrated favorable early rates of hearing preservation with a slim modiolar array. Performance was not significantly different in individuals with and without preserved low-frequency acoustic hearing, independent of EAS use. Compared with reports of short electrode use, the loss of residual hearing in patients implanted with this array did not impact speech perception performance.

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:To prospectively evaluate the frailty phenotype in a population of older adults and determine its association with 1) perioperative complications, 2) need for vestibular rehabilitation after surgery, and 3) early speech perception outcomes. STUDY DESIGN/METHODS:Prospective cohort study. SETTING/METHODS:Tertiary care hospital. PATIENTS/METHODS:Adults older than 65 years undergoing cochlear implantation. INTERVENTIONS/METHODS:The Fried Frailty Index was used to classify patients as frail, prefrail, or not frail based on five criteria: 1) gait speed, 2) grip strength, 3) unintentional weight loss, 4) weekly physical activity, and 5) self-reported exhaustion. MAIN OUTCOMES MEASURES/METHODS:Rates of intraoperative and postoperative complications, postoperative falls, need for vestibular rehabilitation, and early speech perception outcomes. RESULTS:Forty-six patients were enrolled in this study. Five patients (10.8%) were categorized as frail and 10 (21.7%) as prefrail. The mean ages of frail, prefrail, and not frail patients were 80.9, 78.8, and 77.5, respectively. There were no intraoperative complications among all groups. Three patients required postoperative vestibular rehabilitation; all were not frail. One postoperative fall occurred in a nonfrail individual. Mean (standard deviation) device use times at 3 months in frail, prefrail, and not frail patients were 7.6 (3.5), 11.1 (3.6), and 11.6 (2.9) hours per day, respectively. Consonant-nucleus-consonant word scores 3 months after surgery in frail, prefrail, and not frail patients were 13% (12.2), 44% (19.7), and 51% (22.4), respectively. The median (range) number of missed follow-up visits (surgeon, audiologist, speech language pathologist combined) was 7 (1-10) in frail patients, compared with a median of 3 (0-4) and 2 (0-5) in prefrail and not frail patients. CONCLUSIONS:Frail patients did not have increased rates of surgical complications, need for vestibular rehabilitation, or postoperative falls. However, frail patients experienced challenges in accessing postoperative care, which may be addressed by using remote programming and rehabilitation.

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.

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.

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.

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.