Facial Reanimation After Intratemporal Facial Nerve Schwannoma Resection: A Systematic Review.

Objective: To systematically analyze the outcomes of reanimation techniques that have been described for patients undergoing non-fascicle sparing resection of intratemporal facial schwannomas. Methods: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines of the PubMed, MEDLINE, and Cochrane Central Register of Controlled Trials databases. Results: Eight hundred forty studies were screened with 22 meeting inclusion criteria comprising 266 patients. Most facial nerve reanimations (81.2%) were performed using an interposition nerve graft. The remaining patients underwent hypoglossal-facial nerve transposition (13.9%), primary anastomosis (3.4%), and free muscle transfer (0.1%). Of the reported interposition grafts, the two most utilized were the great auricular (113/199) and sural (86/199) nerves. Interposition nerve grafts resulted in significantly better outcomes in facial nerve function postoperatively than hypoglossal-facial transposition (3.48 vs. 3.92; p < 0.01). There was no difference between interposition grafts. Conclusion: This study systematically reports that interposition nerve grafts, after resection of intratemporal facial schwannoma, result in superior outcomes than hypoglossal-facial nerve transposition in these patients.

Bilateral cochlear implantation after immunotherapy-related profound hearing loss: A case report.

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.

Slim Modiolar Electrode Placement in Candidates for Electroacoustic Stimulation.

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.

HiRes ultra series cochlear implant field recall: failure rates and early outcomes.

OBJECTIVE: 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: 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: Of 113 at-risk devices, 20 devices (17.7%) in 18 patients (two bilaterally implanted) were identified as failures. All devices were with mid-scala electrodes. Eleven patients (61.1%) were children and 7 (38.9%) adults. Twelve patients were found to have failing devices after reporting subjective performance decline; the remainder were prompted by manufacturer notification. All were revised, with the majority (83.3%) choosing the same manufacturer. All had uncomplicated original and revision insertions. Among adults, average word scores on the revised side were stable pre- to post-revision (P = 0.95). DISCUSSION: 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: 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.

The Frailty Phenotype in Older Adults Undergoing Cochlear Implantation.

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: Prospective cohort study. SETTING: Tertiary care hospital. PATIENTS: Adults older than 65 years undergoing cochlear implantation. INTERVENTIONS: 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: 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.

Cochlear Implantation Outcomes in Patients With Retrocochlear Pathology: A Systematic Review and Pooled Analysis.

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: 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: Cochlear implantation in patients with concomitant retrocochlear pathology generally results in improved speech discrimination scores sustained over time.

The Natural History of Primary Inner Ear Schwannomas: Outcomes of Long-Term Follow-Up.

OBJECTIVE: To describe the natural history of primary inner ear schwannomas over a long follow-up period. STUDY DESIGN: Retrospective case series. SETTING: Tertiary referral center. PATIENTS: Patients with primary inner ear schwannomas with serial audiometric and radiologic follow-up. MAIN OUTCOME MEASURES: 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 (American Academy of Otolaryngology-Head and Neck Surgery 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: 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.

Modern Hearing Preservation Outcomes After Vestibular Schwannoma Stereotactic Radiosurgery.

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: 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.

Modifications to Implanting the OSIA® 2 Bone Conduction Hearing Implant: How I Do it.

This "How I Do It" report describes modifications made to the OSIA bone conduction hearing implant surgery in order to reduce wound complications. Laryngoscope, 132:1850-1854, 2022.

Stimulating the Cochlear Apex Without Longer Electrodes: Preliminary Results With a New Approach.

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: Three adult patients who underwent cochlear implantation using this new technique. INTERVENTIONS: 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: 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.

Outcomes of Salvage Resection and Radiosurgery Following Failed Primary Treatment of Vestibular Schwannomas.

OBJECTIVE: To evaluate outcomes following salvage microsurgery (MS) and salvage stereotactic radiosurgery (SRS) after failure of primary treatment for vestibular schwannomas (VS). STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. METHODS: Patients with more than 1 intervention for their VS were divided into 4 groups: MS followed by SRS (n = 61), MS followed by MS (n = 9), SRS followed by MS (n = 7), and SRS followed by SRS (n = 7), and outcomes were evaluated. RESULTS: A total of 77 patients were included (84 procedures). In group 1 (MS then SRS), 3% developed a decline in facial function, 3% developed trigeminal sensory loss, and 13% patients had gradual improvement of facial nerve function following SRS. Group 2 (MS then MS) had the highest rates of facial nerve deterioration, although all but 1 patient achieved a House-Brackmann score of II or III. Gross-total resection (GTR) was achieved in 56% of patients. When a different approach was used for salvage resection, GTR occurred more commonly, and facial nerve outcomes were similar. In group 3 (SRS then MS), GTR occurred in 43% of cases, and 2 of 7 patients developed worsened facial function. In group 4 (SRS then SRS), no patient developed facial weakness after reirradiation, and 1 developed a trigeminal nerve deficit. CONCLUSIONS: For MS recurrences/residuals, SRS is the mainstay of treatment and does not preclude facial function recovery. If salvage microsurgery is required, an alternate approach should be considered. For SRS failures, when MS is required, less-than GTR may be preferable, and reirradiation is a potential safe alternative.

Force and pressure measurements in temporal bones.

PURPOSE: Some cochlear implant (CI) patients lose their residual hearing during surgery. Two factors that might play a role in residual hearing loss are the change in intracochlear hydraulic pressure and force on the cochlear wall during electrode insertion. The aim of this study is to investigate whether a difference in peak hydraulic pressure and peak force on the cochlear wall exists during a CI electrode insertion with different insertion techniques. MATERIALS AND METHODS: Twenty fresh frozen temporal bones were used. Hydraulic pressure and force on the cochlear wall were recorded during straight electrode insertions with 1) slow versus fast insertion speed, 2) manual versus automatic insertion method and 3) round window approach (RWA) versus extended RWA (ERWA). RESULTS: When inserting with a slow compared to a fast insertion speed, the peak hydraulic pressure is 239% (95% CI: 130-399%) higher with a RWA and 58% (95% CI: 6-137%) higher with an ERWA. However, the peak force on the cochlear wall is a factor 29% less (95% CI: 13-43%) with a slow insertion speed. No effect was found of opening and insertion method. CONCLUSIONS: As contradictory findings were found for hydraulic pressure and force on the cochlear wall on insertion speed, it remains unclear which insertion speed (slow versus fast) is less traumatic to inner ear structure.

Cochlear Implant Outcomes in Neurofibromatosis Type 2: Implications for Management.

OBJECTIVE: To describe our institutional experience with cochlear implantation (CI) for rehabilitation of hearing loss in Neurofibromatosis type 2 (NF2) patients. STUDY DESIGN: Retrospective review between 1989 and 2019. SETTING: Tertiary-care center. PATIENTS: Twenty-four patients (67% female, mean age 45.6years) with NF2. Management of their ipsilateral vestibular schwannoma included microsurgery (n=12), stereotactic radiation (n=5), and observation (n=7). INTERVENTIONS: Cochlear implantation. MAIN OUTCOME MEASURES: Ability to obtain open-set speech, daily device usage and long-term device benefit. RESULTS: All patients achieved some degree of sound awareness with CI. Nineteen patients (79%) achieved open-set speech understanding with a mean word-recognition score of 43% (range 0-88%). Patients with tumors 1.5 cm or less demonstrated the better speech understanding, without significant differences among treatment modalities. For tumors greater than 1.5 cm, patients who underwent microsurgery had a lower rate of open-set speech understanding compared to those treated with radiation or observation. Regular daily device use in 83% of patients was found. Long-term use (>10years) was observed in several patients, though some ultimately required reimplantation with an auditory brainstem implant due to progressive tumor growth. Mean follow-up duration was 4.1 years (range 0.4-15). CONCLUSIONS: Cochlear implantation can be an effective treatment for hearing loss in NF2 patients provided the cochlear nerve is intact, regardless of prior management for the ipsilateral tumor. The degree of benefit varies and is influenced by tumor size. Management strategies that preserve the cochlear nerve maximize the interval during which a CI could be of benefit to NF2 patients.

Cochlear Implantation in Sporadic Vestibular Schwannoma and Other Retrocochlear Pathology: A Case Series.

OBJECTIVE: To describe outcomes with cochlear implantation (CI) for rehabilitation of hearing loss in patients with sporadic vestibular schwannomas (VS) and other retrocochlear pathologies. STUDY DESIGN: Retrospective review. SETTING: Tertiary-care center. PATIENTS: Twenty three cases in 19 patients (53% men, mean age 55.8 yr) with non-neurofibromatosis type 2 related retrocochlear pathology. INTERVENTIONS: Unilateral or bilateral CI. MAIN OUTCOME MEASURES: Word recognition score, device usage. RESULTS: Etiology of deafness included sporadic VS (n = 9, 39%), radiation after head and neck or central nervous system (CNS) malignancy (n = 8, 35%), superficial siderosis (n = 3, 13%), neurosarcoidosis (n = 2, 9%), and pontine stroke (n = 1, 4%). Mean follow-up duration was 2.3 years (standard deviation [SD] 3.0; range, 0.2-9.4). Auditory perception was achieved in 20 out of 22 patients (91%) who have been activated. Mean WRS in patients with sporadic VS was 18% (SD 20; range, 0-44). Mean WRS in patients with non-VS retrocochlear pathology was 55% (SD 30; range, 0-94). Data logs showed 7.0 h/d of average use (SD 4.3; range, 0-13). CONCLUSIONS: Appropriately selected patients with retrocochlear pathology may benefit from CI so long as the patient has a cochlear fluid signal and an intact cochlear nerve. Patients with sporadic VS patients and normal contralateral hearing exhibited guarded outcomes with CI, whereas most patients with non-VS retrocochlear pathologies demonstrated open-set speech understanding scores comparable to or slightly worse than conventional CI candidates. Since variable performance benefit is observed with CI in patients with retrocochlear pathology, counseling is imperative to align patient expectations with realistic outcomes.

Adherence to Subspecialty Guidelines in the Emergency Department.

OBJECTIVES/HYPOTHESIS: The American Academy of Otolaryngology-Head and Neck Surgery has published clinical practice guidelines (CPGs) to guide management of common otolaryngologic (ENT) conditions. While these CPGs have been disseminated within specialty journals, many patients' first presentation of certain ENT complaints is to primary and acute care settings, including the emergency department (ED). It is less clear whether practice in these settings is concordant with specialty CPGs. STUDY DESIGN: Retrospective cohort study. METHODS: A retrospective review of medical records was performed at an academic tertiary care center with ED diagnoses of 1) Bell's palsy/facial weakness (BP) or 2) acute otitis externa (AOE) from May 2014-June 2018. Individual chart abstraction was performed for all encounters with these diagnoses for the purpose of assessing providers' adherence to CPGs. RESULTS: During the study period, 224 patients were diagnosed with BP and 465 patients were diagnosed with AOE. Of the patients diagnosed with BP, 94% (n = 211/224) were prescribed oral steroids, concordant with guidelines, while 36% of these patients received head computed tomography (CT) scans and 43% received laboratory tests, counter to the guidelines. For those with a diagnosis of AOE, 28.6% received topical antibiotics only as primary treatment (n = 133/465) in accordance with guidelines while systemic antibiotics were prescribed in 42.2% (n = 196/465) discordant with the guidelines and 29.2% received both topical and systemic antibiotics (n = 136/465). CONCLUSIONS: CPGs developed by subspecialty societies provide evidence-based recommendations for the care of patients with particular conditions, but may not be disseminated broadly outside of the specialty. Further research is required to understand the reasons behind divergent management of such conditions. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:1266-1270, 2021.

Risk Factors and Management of Postoperative Infection Following Cochlear Implantation.

OBJECTIVE: To determine factors associated with infection, management, and resultant outcomes following pediatric cochlear implantation. STUDY DESIGN: Retrospective cohort study with nested case series. SETTING: Tertiary academic medical center. PATIENTS: Children who underwent either unilateral or bilateral cochlear implantation between June 2011 and September 2016 and were under the age of 18 at the time of surgery. INTERVENTION(S): Subjects were compared based on age, cochlea malformation, revision surgery, operative time, device manufacturer, and antibiotic use. Infections were compared based on location, time, bacteria, management, and resolution. MAIN OUTCOME MEASURE(S): Rate of infection, rate of device explantation. RESULTS: There were 16 infections among 246 surgeries, an infection rate of 6.5%. There was a significant age difference between infected and noninfected patients overall (n = 246, 1.4 versus 4.3 years, p = 0.005), but not within the cohort of patients five or younger (n = 172, 1.4 versus 1.8 years, p = 0.363). The most common infectious complication was skin infection, followed by device infection. No cases of meningitis were seen. The most common organism was S Aureus. The implant was salvaged in 9 of 16 patients (56.3%), with higher rates in patients treated with IV versus oral antibiotics (70 versus 40%). CONCLUSIONS: Postoperative infection is positively associated with younger age overall, but not in patients below the age of 5. With modern devices and surgical practices, risk of meningitis-though a concern-may be lower than cited in the literature. Prompt and aggressive therapy with IV antibiotics and operative intervention can allow for high rates of device salvage.

Comparison of Skull Radiograph and Computed Tomography Measurements of Cochlear Implant Insertion Angles.

BACKGROUND: Measurement of the angular depth of insertion (aDOI) of cochlear implant electrode arrays has numerous clinical and research applications. Plain-film radiographs are easily obtained intraoperatively and have been described as a means to calculate aDOI. CT imaging with 3D reformatting can also be used for this measurement, but is less conveniently obtained and requires higher radiation doses, a particular concern in pediatrics. The extent to which plain-film and 3D CT image-based measurements are representative of the true position of the electrode within the cochlea is unknown. METHODS: Cochlear implantation was performed on 10 cadaveric temporal bones. Five bones were implanted with perimodiolar electrodes (Contour Advance TM, Cochlear, Sydney, Australia) and five were implanted with lateral wall electrodes (Slim Straight, Cochlear). The insertion depths of the electrodes were varied. Each bone was imaged with a radiograph and CT. aDOI was measured for each bone in each imaging modality by a neurotologist and a neuroradiologist. To obtain a 'gold standard' estimate of aDOI, the implanted temporal bones were embedded in an epoxy resin and methodically sectioned at 100 µm intervals; histologic images were captured at each interval. A 3D stack of the images was compounded, and a MATLAB script used to calculate aDOI of the most apical electrode. Measurements in the three modalities (radiograph, CT, and histology) were then compared. RESULTS: The average aDOI across all bones was similar for all modalities: 423° for radiographs, 425° for CT scans, and 427° for histology, indicating that neither imaging modality resulted in large systematic errors. Using the histology-measured angles as a reference, the average error for CT-based measures (regardless of whether the error was in the positive or negative direction) was 12°, and that for radiograph-based measures was 15°. This small difference (12 vs 15° error) was not statistically significant. CONCLUSION: Based on this cadaveric temporal bone model, both radiographs and CTs can provide reasonably accurate aDOI measurements. In this small sample, and as expected, the CT-based estimates were more accurate than the radiograph-based measurements. However, the difference was small and not statistically significant. Thus, the use of plain radiographs to calculate aDOI seems judicious whenever it is desired to prevent unnecessary radiation exposure and expense.

Comparing costs of microsurgical resection and stereotactic radiosurgery for vestibular schwannoma.

OBJECTIVE: Given rising scrutiny of healthcare expenditures, understanding intervention costs is increasingly important. This study aimed to compare and characterize costs for vestibular schwannoma (VS) management with microsurgery and radiosurgery to inform practice decisions and appraise cost reduction strategies. METHODS: In conjunction with medical records, internal hospital financial data were used to evaluate costs. Total cost was divided into index costs (costs from arrival through discharge for initial intervention) and follow-up costs (through 36 months) for 317 patients with unilateral VSs undergoing initial management between June 2011 and December 2015. A retrospective matched cohort based on tumor size with 176 patients (88 undergoing each intervention) was created to objectively compare costs between microsurgery and radiosurgery. The full sample of 203 patients treated with resection and 114 patients who underwent radiosurgery was used to evaluate a broad range of outcomes and identify cost contributors within each intervention group. RESULTS: Within the matched cohort, average index costs were significantly higher for microsurgery (100% by definition, because costs are presented as a percentage of the average index cost for the matched microsurgery group; 95% CI 93-107) compared to radiosurgery (38%, 95% CI 38-39). Microsurgery had higher average follow-up costs (1.6% per month, 95% CI 0.8%-2.4%) compared to radiosurgery (0.5% per month, 95% CI 0.4%-0.7%), largely due to costs incurred in the initial months after resection. A major contributor to total cost and cost variability for both resection and radiosurgery was the need for additional interventions in the follow-up period, which were necessary due to complications or persistent functional deficits. Although tumor size was not associated with increased total costs for radiosurgery, linear regression analysis demonstrated that, for patients who underwent microsurgery, each centimeter increase in tumor maximum diameter resulted in an estimated increase in total cost of 50.2% of the average index cost of microsurgery (95% CI 34.6%-65.7%) (p < 0.001, R2 = 0.17). There were no cost differences associated with the proportion of inpatient days in the ICU or with specific surgical approach for patients who underwent resection. CONCLUSIONS: This study is the largest assessment to date based on internal cost data comparing VS management with microsurgery and radiosurgery. Both index and follow-up costs are significantly higher when tumors were managed with resection compared to radiosurgery. Larger tumors were associated with increased resection costs, highlighting the incremental costs associated with observation as the initial management.

A matched cohort comparison of clinical outcomes following microsurgical resection or stereotactic radiosurgery for patients with small- and medium-sized vestibular schwannomas.

OBJECTIVE A randomized trial that compares clinical outcomes following microsurgery (MS) or stereotactic radiosurgery (SRS) for patients with small- and medium-sized vestibular schwannomas (VSs) is impractical, but would have important implications for clinical decision making. A matched cohort analysis was conducted to evaluate clinical outcomes in patients treated with MS or SRS. METHODS The records of 399 VS patients who were cared for by 2 neurosurgeons and 1 neurotologist between 2001 and 2014 were evaluated. From this data set, 3 retrospective matched cohorts were created to compare hearing preservation (21 matched pairs), facial nerve preservation (83 matched pairs), intervention-free survival, and complication rates (85 matched pairs) between cases managed with SRS and patients managed with MS. Cases were matched for age at surgery (± 10 years) and lesion size (± 0.1 cm). To compare hearing outcomes, cases were additionally matched for preoperative Class A hearing according to the American Academy of Otolaryngology-Head and Neck Surgery guidelines. To compare facial nerve (i.e., cranial nerve [CN] VII) outcomes, cases were additionally matched for preoperative House-Brackmann (HB) score. Investigators who were not involved with patient care reviewed the clinical and imaging records. The reported outcomes were as assessed at the time of the last follow-up, unless otherwise stated. RESULTS The preservation of preoperative Class A hearing status was achieved in 14.3% of MS cases compared with 42.9% of SRS cases (OR 4.5; p < 0.05) after an average follow-up interval of 43.7 months and 30.3 months, respectively. Serviceable hearing was preserved in 42.8% of MS cases compared with 85.7% of SRS cases (OR 8.0; p < 0.01). The rates of postoperative CN VII dysfunction were low for both groups, although significantly higher in the MS group (HB III-IV 11% vs 0% for SRS; OR 21.3; p < 0.01) at a median follow-up interval of 35.7 and 19.0 months for MS and SRS, respectively. There was no difference in the need for subsequent intervention (2 MS patients and 2 SRS patients). CONCLUSIONS At this high-volume center, VS resection or radiosurgery for tumors ≤ 2.8 cm in diameter was associated with low overall morbidity. The need for subsequent intervention was the same in both groups. SRS was associated with improved hearing and facial preservation rates and reduced morbidity, but with a shorter average follow-up period. Facial function was excellent in both groups. Since patients were not randomly selected for surgery, different clinical outcomes may be of different value to individual patients. Both anticipated medical outcomes and patient goals remain the drivers of treatment decisions.

Measurement of Cochlear Implant Electrode Position From Intraoperative Post-insertion Skull Radiographs: A Validation Study.

OBJECTIVE: To validate a method of measuring angular depth of insertion (aDOI) as well as positional depth of each electrode contact in a cochlear implant by using intraoperative postinsertion skull radiographs. STUDY DESIGN: Retrospective review. SETTING: Tertiary referral center. PATIENTS: Intraoperative postinsertion radiographs obtained from 18 cochlear implant recipients were chosen for analysis. One high-resolution computer tomography scan of the head with the electrode in place was also analyzed. One cadaveric temporal bone with an inserted electrode provided additional data for analysis. INTERVENTION: aDOI and position of each electrode contact were measured from the radiographs using readily available software. High-resolution computer tomography imaging of the cochlea and electrode were reconstructed in three dimensions and used to simulate head rotation during intraoperative radiographs. The cadaveric temporal bone was imaged by x-ray at various acquisition angles. MAIN OUTCOME MEASURES: We evaluated the error introduced in measuring aDOI by assessing intra- and inter-rater variability. We also evaluated the error introduced by x-ray acquisition at nonstandardized angles by analyzing the three-dimensional construct and the cadaveric temporal bone. RESULTS: The concordance correlation coefficients for intrarater (0.991) and inter-rater (0.996) variability in aDOI measurement were excellent. The error introduced by nonstandardized x-ray acquisition angles was only -12.5 degrees to +15.8 degrees even at the limits of clinically relevant head rotation. CONCLUSIONS: The intraoperative postinsertion radiograph is sufficient for estimating positional depth of electrode contacts and the aDOI. This measure is robust in the face of nonstandardized x-ray acquisition angles, and shows good intra- and inter-rater variability.