Management Of Vestibular Schwannomas Research Articles

Long-Term Prospective Quality-of-Life Outcomes in 445 Patients with Sporadic Vestibular Schwannoma.

To evaluate the long-term changes in sporadic vestibular schwannoma (VS) disease-specific quality-of-life (QOL) outcomes. Prospective longitudinal study using the Penn Acoustic Neuroma Quality of Life (PANQOL) Scale. National survey. Patients with sporadic VS who completed a baseline survey before treatment and at least one follow-up survey recruited through the authors' center and through the Acoustic Neuroma Association. Observation, microsurgery, radiosurgery. Changes in PANQOL scores from baseline to most recent survey. Among 445 eligible patients the mean duration of follow-up was 4.4 (SD, 2.3) years, including 122, 218, and 105 in the observation, microsurgery, and radiosurgery groups, respectively. Patients managed with observation (p = 0.03) or microsurgery (p < 0.001) demonstrated improvement in anxiety scores. Changes in facial function scores differed significantly by management group (p = 0.01), with patients undergoing microsurgery demonstrating a mean decline of 10 points in facial function scores compared with mean declines of 3 for those managed with observation or radiosurgery. Hearing loss scores decreased similarly over time for all three groups (p = 0.3). There were minimal changes in total PANQOL scores over time across all management groups (p = 0.5). Long-term changes in total QOL among VS management groups are not significantly different. Microsurgery may continue to confer an advantage regarding improvement in anxiety postoperatively, but with a greater decline in facial function when compared to observation or radiosurgery. Long-term declines in hearing loss scores were not statistically significantly different among groups.

Current trends in vestibular schwannoma management at a referral center in Indonesia: A cross-sectional study with retrospective data collection

Background. Vestibular schwannoma (VS) is the most common benign brain tumor of the cerebellopontine angle. Due to its location, this pathology can create both focal and general deficits. The registry system for VS in Indonesia is developing, including in the author’s institution, which eventually shows a changing trend in managing VS. Methods. We retrospectively collected data from all patients diagnosed with vestibular schwannoma, based on histological or radiological results. Treatments included craniotomy and/or Gamma Knife Radiosurgery (GKRS) from 2018 to 2023. Results. Data from 88 patients were analyzed. The number of treated patients has increased annually. VS predominantly affects females (64%). The proportion between GKRS and craniotomy procedures also shifted throughout the year. Common symptoms included hearing loss (63.6%), disequilibrium (50%), and headaches (39.7%). The most common tumor size was medium (15-30 mm; n=37; 42%). Tumors that fell into the intrameatal and small (&lt;15 mm) categories were all treated with GKRS, whereas the other groups were divided into GKRS and craniotomy. GKRS demonstrated high efficacy in tumor control and favorable hearing and facial nerve preservation, whereas craniotomy remained crucial for larger tumors. Conclusion. The number of VS diagnosed each year has increased in our center, accompanied by a noticeable shift in preference from GKRS to craniotomy, which is influenced by the integration of intraoperative monitoring. Treatment preference was further determined based on the clinical profile and tumor size. In the future, there is a need to develop a national registry to better reflect the true incidence of VS within the Indonesian population.

Hearing preservation and quality of life in small to medium sized vestibular schwannomas after a wait and scan approach or stereotactic radiosurgery: a systematic review and meta-analysis.

The management of vestibular schwannomas (VS) encompasses a choice between conservative "wait-and-scan" (WAS) approach, stereotactic radiosurgery (SRS) or open microsurgical resection. Currently, there is no consensus on the optimal management approach for small to mediumsized VS. This study aims to compared outcomes related to hearing in patients with small and mediumsized VS who underwent initial treatment with WAS versus SRS. A systematic review of the available literature was conducted using PubMed/MEDLINE, Embase, and Cochrane up December 08, 2023. Meta-analysis was performed using a random-effect model to calculate mean difference (MD) and relative risk (RR). A leave-one-out analysis was conducted. The risk of bias was assessed via the Risk of Bias in Non-randomized Studies-Interventions (ROBINS-I) and Cochrane Risk of Bias assessment tool (RoB-2). Ultimately, the certainty of evidence was evaluated using the GRADE assessment. The primary outcomes were serviceable hearing, and pure-tone average (PTA). The secondary outcome was the Penn Acoustic Neuroma Quality of Life Scale (PANQOL) total score. Nine studies were eligible for inclusion, comprising a total of 1,275 patients. Among these, 674 (52.86%) underwent WAS, while 601 patients (47.14%) received SRS. Follow-up duration ranged from two to eight years. The meta-analysis indicated that WAS had a better outcome for serviceable hearing (0.47; 95% CI: 0.32 - 0.68; p < 0.001), as well as for postoperative functional measures including PTA score (MD 13.48; 95% CI 3.83 - 23.13; p < 0.01), and PANQOL total score (MD 3.83; 95% CI 0.42 - 7.25; p = 0.03). The overall certainty of evidence ranged from "very low" to "moderate". Treating small to mediumsized VS with WAS increases the likelihood of preserving serviceable hearing and optimized PANQOL overall postoperative score compared to SRS. Nevertheless, the limited availability of literature and the methodological weakness observed in existing studies outline the need for higher-quality studies.

Predictors of Prolonged Hospital Stay After Microsurgery for Vestibular Schwannoma: Analysis of a Decade of Data.

Microsurgical resection is one of the treatments for vestibular schwannomas (VS). While several factors have been linked to increased length of stay (LOS) for VS patients undergoing microsurgery, a better understanding of these factors is important to provide prognostic information for patients. Determine predictors of increased LOS for VS patients undergoing microsurgical resection. Retrospective analysis using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2010 to 2020. Database review. All patients who underwent microsurgery (CPT codes 61520, 61526/61596) for the management of vestibular schwannoma (ICD9 and ICD10 codes 225.1, D33.3) were included. Analyzing perioperative factors that can predict prolonged hospital stay. A total of 2096 cases were identified and 1,188 (57%) of these patients were female. The mean age was 51.0 ± 14.0 years. Factors contributing to prolonged LOS included African American race (OR = 2.11, 95% CI: 1.32-3.36, p = 0.002), insulin-dependent diabetes mellitus (OR = 2.12, 95% CI: 1.09-4.4.11, p = 0.026), hypertension (OR = 1.26, 95% CI: 1-1.58, p = 0.046), functional dependency (OR = 5.22, 95% CI: 2.31-11.79, p = 0.001), prior steroid use (OR = 1.96, 95% CI: 1.18-3.15, p = 0.009), ASA class III (OR = 2.06, 95% CI: 1.18-3.6, p < 0.011), ASA class IV (OR = 6.34, 95% CI: 2.62-15.33, p < 0.001), and prolonged operative time (OR = 2.14, 95% CI: 1.76-2.61). Microsurgery by a translabyrinthine (TL) approach compared to a retrosigmoid (RSG) approach had lower odds of prolonged LOS (OR = 0.67, 95% CI: 0.54-0.82, p < 0.001). In a separate analysis regarding patients receiving reoperation, operative time was the only predictor of prolonged LOS (OR = 2.77, 95% CI: 1.39-5.53, p = 0.004.). Our analysis offers an analysis of the factors associated with a prolonged LOS for the surgical management of VS. By identifying healthcare disparities, targeting modifiable factors, and applying risk stratification based on demographics and comorbidities, we can work toward reducing disparities in LOS and enhancing patient outcomes.

Repeat stereotactic radiosurgery for progressive vestibular schwannomas after primary gamma knife radiosurgery

PurposeLimited data provides guidance on the management of vestibular schwannomas (VSs) that have progressed despite primary Gamma Knife radiosurgery (GKRS). The present article reports our long-term experience after repeat GKRS for VS with sustained progression after solely primary GKRS management.MethodsA retrospective review of 1997 patients managed between 1987 and 2023 was conducted. Eighteen patients had sustained tumor progression after primary GKRS and underwent repeat GKRS. The median repeat GKRS margin dose was 11 Gy (IQR: 11–12), the median tumor volume was 2.0 cc (IQR: 1.3–6.3), and the median cochlear dose in patients with preserved hearing was 3.9 Gy (IQR: 3-4.1). The median time between initial and repeat GKRS was 65 months (IQR: 38–118).ResultsThe median follow-up was 70 months (IQR: 23–101). After repeat GKRS, two patients had further tumor progression at 4 and 21 months and required partial resection of their tumors. The 10-year actuarial tumor control rate after repeat GKRS was 88%. Facial nerve function was preserved in 13 patients who had House-Brackmann grade 1 or 2 function at the time of repeat GKRS. Two patients with serviceable hearing preservation (Gardner-Robertson grade 1 or 2) at repeat GKRS retained that function afterwards. In patients with tinnitus, vestibular dysfunction, and trigeminal neuropathy, symptoms remained stable or improved for 16/16 patients, 12/15 patients, and 10/12 patients, respectively. One patient developed facial twitching in the absence of tumor growth 21 months after repeat GKRS.ConclusionsRepeat GKRS effectively controlled tumor growth and preserved cranial nerve outcomes in most patients whose VS had sustained progression after initial primary radiosurgery.

Vestibular Schwannoma Management: Patient Perspectives and Health Literacy

Objective: To assess medical decision-making, reasons for attrition, and health literacy among vestibular schwannoma (VS) patients last seen in clinic more than 2 years ago. Study Design: Survey. Setting: Tertiary skull base center. Patients: Adults with sporadic VS last evaluated more than 2 years ago. Methods: Survey including Brief Health Literacy Screen (BHLS), a validated 3-question measure of health literacy, and open-ended questions on care; retrospective chart review. Main Outcome Measures: BHLS score, patient reasons for attrition. Results: Of 1011 patients contacted, 205 (20.3%) patients responded and met all criteria for analysis. At initial evaluation, mean patient age was 50.6 ± 12.8 years, roughly half (51.4%) were female, and the majority (80.2%) identified as White. At the time of the survey, 48 (23%) continued to observe their tumor. The remaining 160 (76.9%) patients previously underwent treatment (surgery and/or radiation). Of those treated, 34 (21.3%) underwent intervention elsewhere. Symptoms since the last patient visit did not differ between observed and treated patients. About 94.7% of the cohort displayed high health literacy (BHLS &gt; 9), though rates of inadequate health literacy were higher among observed patients (12.5% versus 3.1% in those treated). The most common reasons for opting not to follow-up included counseling issues, personal decisions, and social/life stressors (including the COVID-19 pandemic). Conclusions: Despite being a highly health-literate cohort, patients cited multiple reasons for attrition. Regardless of whether they were observed or treated, patients described follow-up visits as burdensome and perceived them to be of minimal benefit.

"To implant or not to implant": electrically evoked auditory brainstem response audiometry for decision-making in vestibular schwannoma resection with CI.

Vestibular schwannomas (VS) are often associated with debilitating hearing loss. Therefore, preservation and rehabilitation of hearing have become major therapeutic goals of VS management. Recently, cochlear implantation (CI) has been established as an effective treatment option for VS-associated hearing loss. Nevertheless, the integrity and proper function of the cochlear nerve must be evaluated before conducting CI to ensure optimal CI outcomes. Various methods to determine cochlear nerve integrity and functionality have emerged in the last few years. Of these, the use of electrically evoked auditory brainstem response audiometry (eABR) in particular has been proven to be ameaningful tool for monitoring cochlear nerve health during VS surgery. Here, the cochlear nerve can be electrically stimulated using an intracochlear test electrode before, during, and after tumor extirpation. Subsequently, the resulting brainstem responses can be measured and interpreted accordingly to obtain direct information on the cochlear nerve function. This allows for continuous monitoring of cochlear nerve function throughout the course of VS surgery and aids in the decision-making for CI candidacy. Finally, in the case of preserved brainstem responses, CI can be performed instantly after VS extirpation. This simultaneous approach offers several advantages over two-staged procedures and has been shown to be an efficient and safe procedure for restoring hearing after VS removal.

Comparison of quality of life in vestibular schwannoma patients managed with observation, radiotherapy or microsurgery.

In decision making regarding the management of vestibular schwannomas, alongside clinical outcomes, an understanding of patient reported health-related quality of life measures is key. Therefore, the aim of this research is to compare health-related quality of life in vestibular schwannoma patients treated with active observation, stereotactic radiotherapy and microsurgical excision. A cross-sectional study of patients diagnosed with unilateral sporadic vestibular schwannomas between 1995 and 2015 at a specialist tertiary centre was conducted. Patients completed the Penn Acoustic Neuroma Quality of Life questionnaire and handicap inventories for dizziness, hearing and tinnitus. Of 234 patients, 136 responded (58.1 per cent). Management modality was: 86 observation, 23 stereotactic radiotherapy and 25 microsurgery. Females reported significantly worse dizziness; males reported significantly worse physical disability. Patients less than 65 years old reported significantly worse tinnitus and pain scores. Overall, quality of life was higher in the observation group. Conservative management, where appropriate, is favourable with higher quality-of-life outcomes in this cohort. This must be weighed against the risks of a growing tumour.

The impact of multiple deprivation on the management of vestibular schwannomas.

While some factors have been well-shown to affect the decision-making in treating patients with vestibular schwannomas (VS), little is known on the role of deprivation. Our objective was to assess the effect of socioeconomic background on the management of patients with VS. This retrospective cohort study included 460 patients with sporadic VS from West of Scotland. The postcode-based, multifactorial Scottish Index of Multiple Deprivation (SIMD) was used to assess the socioeconomic background of each patient. We performed a multivariate analysis including tumour size, growth and patient age with management modality (observation, stereotactic radiotherapy, microsurgery) being the main outcome measure and outcome (need for additional treatment) an additional measure. We found no significant difference in the demographics, tumour characteristics and primary treatment choice between patients with different SIMD scores. In addition, there was no statistically significant difference in the growth occurrence rates following first-line treatment (p = 0.964) and in the second-line treatment choice (p = 0.460). Multiple deprivation does not affect decision making in patients with VS in the examined cohort. This is probably linked to the centralisation and uniformity of the service and might not necessarily be applicable to other health services without centralisation.

Predictive factors of tinnitus after vestibular schwannoma surgery: a case-control study

BackgroundTinnitus is very common in patients with vestibular schwannoma (VS). We analyzed the related factors of tinnitus after surgery.MethodsOne hundred seventy-three patients diagnosed with unilateral VS operated via the retrosigmoid approach were included in the study. All patients underwent relevant examinations and completed the THI scale before surgery and 6 months after surgery. The prognosis of tinnitus was evaluated according to the changes in THI.ResultsOf the 129 preoperative tinnitus patients, postoperative tinnitus resolved in 12.4%, improved in 29.5%, remained unchanged in 28.6%, and worsened in 29.5%. 18.2% of 44 patients without preoperative tinnitus appeared new-onset tinnitus postoperatively. Thirty-six patients never had tinnitus. Patients with smaller tumor sizes (≤ 3 cm) were more likely to experience preoperative tinnitus. Younger patients and those with serviceable hearing preoperatively were more likely to report their tinnitus unchanged or worsened. A new onset of postoperative tinnitus in the preoperative non-tinnitus group was found in better preoperative hearing function.ConclusionsIn this study, 70% of patients had persistent tinnitus after vestibular schwannoma resection. The prognosis of tinnitus was influenced by age and preoperative hearing function. Tinnitus is a bothersome symptom and is often underestimated by doctors. Assessment of tinnitus is mandatory during the management of vestibular schwannoma.

NeuroGPT-X: toward a clinic-ready large language model.

The objective was to assess the performance of a context-enriched large language model (LLM) compared with international neurosurgical experts on questions related to the management of vestibular schwannoma. Furthermore, another objective was to develop a chat-based platform incorporating in-text citations, references, and memory to enable accurate, relevant, and reliable information in real time. The analysis involved 1) creating a data set through web scraping, 2) developing a chat-based platform called neuroGPT-X, 3) enlisting 8 expert neurosurgeons across international centers to independently create questions (n = 1) and to answer (n = 4) and evaluate responses (n = 3) while blinded, and 4) analyzing the evaluation results on the management of vestibular schwannoma. In the blinded phase, all answers were assessed for accuracy, coherence, relevance, thoroughness, speed, and overall rating. All experts were unblinded and provided their thoughts on the utility and limitations of the tool. In the unblinded phase, all neurosurgeons provided answers to a Likert scale survey and long-answer questions regarding the clinical utility, likelihood of use, and limitations of the tool. The tool was then evaluated on the basis of a set of 103 consensus statements on vestibular schwannoma care from the 8th Quadrennial International Conference on Vestibular Schwannoma. Responses from the naive and context-enriched Generative Pretrained Transformer (GPT) models were consistently rated not significantly different in terms of accuracy, coherence, relevance, thoroughness, and overall performance, and they were often rated significantly higher than expert responses. Both the naive and content-enriched GPT models provided faster responses to the standardized question set than expert neurosurgeon respondents (p < 0.01). The context-enriched GPT model agreed with 98 of the 103 (95%) consensus statements. Of interest, all expert surgeons expressed concerns about the reliability of GPT in accurately addressing the nuances and controversies surrounding the management of vestibular schwannoma. Furthermore, the authors developed neuroGPT-X, a chat-based platform designed to provide point-of-care clinical support and mitigate the limitations of human memory. neuroGPT-X incorporates features such as in-text citations and references to enable accurate, relevant, and reliable information in real time. The present study, with its subspecialist-level performance in generating written responses to complex neurosurgical problems for which evidence-based consensus for management is lacking, suggests that context-enriched LLMs show promise as a point-of-care medical resource. The authors anticipate that this work will be a springboard for expansion into more medical specialties, incorporating evidence-based clinical information and developing expert-level dialogue surrounding LLMs in healthcare.

Managing vestibular schwannomas with radiosurgery and radiotherapy: AGREE II appraisal of clinical practice guidelines.

Vestibular schwannomas (VSs) are rare, benign intracranial tumours that have prompted clinical practice guideline (CPG) creation given their complex management. Our aim was to utilize the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument to assess if such CPGs on the management of VSs with radiosurgery and radiotherapy are of acceptable quality. Relevant CPGs were identified following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocols. Experienced reviewers then extracted general CPG properties and rated their quality via the AGREE II instrument. Intraclass correlation coefficients (ICCs) were quantified to assess interrater reliability. Nine CPGs on the management of VSs with radiosurgery and radiotherapy were identified. All CPGs were created in the past six years and developed recommendations based on literature review and expert consensus. One guideline was deemed as high quality with seven others being moderate and one being low in quality. The clarity of the presentation domain had the highest mean scaled domain score of 96.0%. The domains of stakeholder involvement and applicability had the lowest means of 49.2% and 47.2%, respectively. ICCs were either good or excellent across all domains. Current CPGs on the management of VSs with radiosurgery and radiotherapy are of acceptable quality but would greatly benefit from improvements in applicability, stakeholder involvement, editorial independence and rigour of development. We recommend CPG authors reference the European Association of Neuro-Oncology (EANO) guideline as a developmental framework with the Congress of Neurological Surgeons/American Association of Neurological Surgeons (CNS/AANS) CPG being a valid alternative.

The Recent Management of Vestibular Schwannoma Radiotherapy: A Narrative Review of the Literature.

Radiotherapy (RT) plays an important role in the therapeutic management of vestibular schwannoma (VS). Fractionated stereotactic radiotherapy (FSRT) or radiosurgery (SRS) are the two modalities available. The purpose of this article is to review the results of VS RT studies carried out over the last ten years. A literature search was performed with PubMed and Medline by using the words vestibular schwannoma, acoustic neuroma, radiotherapy, and radiosurgery. In small (<3 cm) VS, SRS offers a local control rate of >90%, which seems similar to microsurgery, with a favorable tolerance profile. Hypofractionated FSRT (three to five fractions) is a relatively recent modality and has shown similar outcomes to normofractionated FSRT. Hearing preservation may highly differ between studies, but it is around 65% at 5 years. SRS and FRST are non-invasive treatment options for VS. SRS is often preferred for small lesions less than 3 cm, and FSRT for larger lesions. However, no randomized study has compared these modalities.

Consensus guidelines for the management of vestibular schwannoma for lowand middle-income countries.

Vestibular Schwannoma (VS), previously known as acoustic neuroma, constitutes the majority of tumours found in the cerebellopontine angle (CPA). Most guidelines for managing CPA tumours have been developed by high-income countries (HICs). However, these guidelines often fall short in addressing the unique challenges encountered in low- and middle-income countries (LMICs), such as Pakistan. In LMICs, issues related to a limited healthcare workforce, inadequate infrastructure, and constrained financial resources hinder the effective implementation of these HIC-derived guidelines. Additionally, it has been observed that VS tends to present at a larger size in LMICs compared to HICs. Given that VS is the predominant type of CPA tumour and other types are covered under separate guidelines, this article aims to provide practical, contextspecific recommendations for the screening, diagnosis, and management of Vestibular Schwannoma in LMIC settings. Our focus is to bridge the gap in care strategies and adapt them to the resource constraints and clinical realities of LMICs.

Salvage Microsurgery Following Failed Primary Radiosurgery in Sporadic Vestibular Schwannoma

Management of sporadic vestibular schwannoma with radiosurgery is becoming increasingly common globally; however, limited data currently characterize patient outcomes in the setting of microsurgical salvage for radiosurgical failure. To describe the clinical outcomes of salvage microsurgery following failed primary stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT) among patients with sporadic vestibular schwannoma. This was a cohort study of adults (≥18 years old) with sporadic vestibular schwannoma who underwent salvage microsurgery following failed primary SRS/FSRT in 7 vestibular schwannoma treatment centers across the US and Norway. Data collection was performed between July 2022 and January 2023, with data analysis performed between January and July 2023. Salvage microsurgical tumor resection. Composite outcome of undergoing less than gross total resection (GTR) or experiencing long-term facial paresis. Among 126 patients, the median (IQR) age at time of salvage microsurgery was 62 (53-70) years, 69 (55%) were female, and 113 of 117 (97%) had tumors that extended into the cerebellopontine angle at time of salvage. Of 125 patients, 96 (76%) underwent primary gamma knife SRS, while 24 (19%) underwent linear accelerator-based SRS; the remaining patients underwent FSRT using other modalities. Postoperative cerebrospinal fluid leak was seen in 15 of 126 patients (12%), hydrocephalus in 8 (6%), symptomatic stroke in 7 (6%), and meningitis in 2 (2%). Each 1-mm increase in cerebellopontine angle tumor size was associated with a 13% increased likelihood of foregoing GTR (64 of 102 patients [63%]) or long-term postoperative House-Brackmann grade higher than I (48 of 102 patients [47%]) (odds ratio, 1.13; 95% CI, 1.04-1.23). Following salvage microsurgery, tumor growth-free survival rates at 1, 3, and 5 years were 97% (95% CI, 94%-100%), 93% (95% CI, 87%-99%), and 91% (95% CI, 84%-98%), respectively. In this cohort study, more than half of patients who received salvage microsurgery following primary SRS/FSRT underwent less than GTR or experienced some degree of facial paresis long term. These data suggest that the cumulative risk of developing facial paresis following primary SRS/FSRT by the end of the patient's journey with treatment approximates 2.5% to 7.5% when using published primary SRS/FSRT long-term tumor control rates.

Surgical salvage for recurrent vestibular schwannoma after primary stereotactic radiosurgery

Background: The management of vestibular schwannoma has evolved over the past hundred years. In the last decades, surgery has been gradually replaced by radiation therapy as a primary treatment modality, particularly for small tumors, due to the less invasive nature and the compared reported outcomes in tumor control and hearing preservation. However, irradiation sometimes fails to stop tumor growth. In a long-term follow-up after primary fractionated stereotactic radiotherapy, the rate of treatment failure was reported as 3% and needed surgical salvage. For single-fraction modality, Hasegawa et al. reported salvage treatment after primary Gamma Knife radiosurgery in 8%, where 90% of these underwent surgery and 50% of those who were treated with a second gamma knife surgery required surgical intervention later. An increase in tumor volume by more than 10–20%, tumor growth after three years, and no return to pretreatment volume after transient swelling have been considered as tumor recurrence rather than pseudoprogression, a transient increase in tumor volume after radiotherapy that occurs up to 30% of cases. It has been reported that microsurgery after radiotherapy is more difficult, with most authors reporting a loss of defined arachnoid planes and worse cranial nerve outcomes, especially for hearing and facial nerve function. Case Description: A 43-year-old female patient was incidentally (asymptomatic) diagnosed on a magnetic resonance imaging (MRI) scan harboring a left vestibular schwannoma, grade T2 (Hannover classification), in 2015. Neurologic examination was unremarkable, and audiometry testing was normal. She was initially treated with observation. Three years later, in 2018, the lesion had enlarged, becoming a grade T3a and reaching the cistern of the cerebellopontine angle. The tumor was then treated with fractionated stereotactic radiosurgery (5 sessions of 5 Gy). MRI scans in 2019 and 2020 showed slight tumor growth. This enlargement was attributed to a pseudoprogression after radiosurgery, and only observation was advocated. In 2022, 4 years later, after radiosurgery, the tumor was still growing, and the patient began to suffer from hearing loss. A failure treatment was considered, and microsurgery was indicated. The patient was counseled about the risk of functional nerve impairment, and surgical consent was obtained. A retro sigmoid approach was planned. A gross total resection was attempted due to the clear subperineural plane during tumor dissection and because it was the only option that would provide a cure for the patient. The adjacent neurovascular structures were firmly adhered to the tumor capsule, which represented a major challenge for microdissection. The tumor was soft, without significant bleeding. A total resection was achieved, and the facial nerve was anatomically preserved. The patient developed facial paresis (House-Brackmann III) in the immediate postoperative period, which improved at the 6-month follow-up. Hearing loss did not improve. Postoperative MRI showed total resection. Conclusion: Microsurgery after radiotherapy for vestibular schwannoma is challenging in terms of indication, when to indicate, resection target, difficulty in dissection due to local changes, and outcome. Gross total resection may be considered, as it is the only treatment that may provide a cure for the patient. However, the patient should be counseled about the risks.

P11.16.B THE MAYO CLINIC MULTIDISCIPLINARY NF2 CLINIC EXPERIENCE OF BEVACIZUMAB IN NEUROFIBROMATOSIS TYPE 2-RELATED SCHWANNOMATOSIS PATIENTS WITH VESTIBULAR SCHWANNOMAS

Abstract BACKGROUND Neurofibromatosis type 2-related schwannomatosis (NF2) is an autosomal dominant tumor-predisposition syndrome characterized by bilateral vestibular schwannomas (VS) as well as other nervous system tumors. Management decisions for NF2-related VS are typically predicated on tumor size, associated symptoms, patient age, and comorbidities. Observation, surgical resection, and stereotactic radiosurgery can be viable options. In patients with VS associated with NF2, vascular endothelial growth factor A (VEGF-A) inhibitor, bevacizumab, is a systemic treatment option. In this single institution study, we review our clinical experience in patients with NF2 who received bevacizumab for VS and evaluate the effect of bevacizumab treatment on VS growth and symptom progression. MATERIAL AND METHODS This is a retrospective analysis of patients seen at the Mayo Clinic Rochester Multidisciplinary NF2 Clinic. Three-dimensional volumetric data for VS were measured using manual segmentation with Visage PACS software under the direct supervision of a board-certified neuroradiologist. RESULTS Out of 76 patients with NF2 evaluated in the past 3 years, we identified 19 that received treatment with bevacizumab. Median age of NF2 diagnosis was 19 years (range 0.5-61) with a median NF2 phenotype severity score of 2 (range 1-3). Thirteen of these patients have discontinued bevacizumab, accounting for a median duration of 12.2 months (range 3.3-88 months) of bevacizumab treatment. Bevacizumab was discontinued due to hypertension (n=5), proteinuria and renal dysfunction (n=3), tumor progression (n=2), fatigue or other intolerance (n=2), or non-compliance (n=1). The remaining 6 patients are currently receiving bevacizumab treatment for a median duration of 9.4 months as of March 2023 (range 3.7-48.3 months). Fifteen patients had brain MRI data available to evaluate VS change during bevacizumab treatment, with partial response observed in 5 patients, stable disease in 8, and progression in 2. Ten of the 13 patients who stopped bevacizumab had MRI data to evaluate VS change following treatment termination. Within 6 months of bevacizumab discontinuation, 6 patients had rebound growth of their VS between 21-95% from their previous tumor volume, while 4 did not. Three patients with rebound growth went on to have surgery or irradiation for VS management. CONCLUSION Our single institution experience confirms that bevacizumab can slow progression of VS and symptoms associated with VS growth. However, we note that there is the potential for rapid VS growth following bevacizumab discontinuation, for which we propose heightened surveillance imaging and symptom monitoring for at least 6 months upon stopping anti-VEGF therapy.

Cochlear Implant Outcomes between Patients with Sporadic and Neurofibromatosis Type 2-Associated Vestibular Schwannoma.

Compare cochlear implant (CI) performance between patients with ipsilateral sporadic vestibular schwannoma (VS) and NF2-related schwannomatosis (NF2). Compare CI performance according to VS management modality. Historical cohort. Tertiary academic center. Forty-nine patients (52 ears) undergoing cochlear implantation in the setting of ipsilateral sporadic (n = 21) or NF2-associated VS (n = 28). CI ipsilateral to VS. Auditory thresholds, consonant-nucleus-consonant (CNC) word scores, and AzBio sentences in quiet scores. Among all patients, median post-CI pure tone average was 28 dB HL (interquartile range [IQR], 21-38), CNC word score was 39% (IQR, 6-62), and AzBio sentences in quiet score was 60% (IQR, 11-83) at a median of 12.5 months postimplantation. Despite the NF2 cohort having larger tumors, when comparing patients with sporadic versus NF2-associated VS, there were no statistically significant differences in CNC word (49% [30-70] vs. 31% [0-52]) or AzBio sentences in quiet (66% [28-80] vs. 57% [5-83]) scores. Regardless of NF2 status, all patients managed with observation, and radiosurgery achieved open-set speech. In patients who underwent microsurgery, 6 (46%) of 13 with NF2 achieved open-set speech recognition compared with 4 (67%) of 6 with sporadic disease. Select patients with VS achieve successful hearing rehabilitation with a CI. In this cohort, tumor management strategy significantly influenced CI performance, whereas differences in NF2 status exhibited less effect. Specifically, all patients managed with observation or radiosurgery achieved open-set speech perception, whereas approximately half of people with NF2-related VS and two-thirds of people with sporadic VS achieved this outcome after tumor microsurgery. When disease permits, observation and radiosurgery should be considered in patients who may later pursue a CI.

Vestibular Schwannoma

Abstract Vestibular schwannoma is a tumor of vestibulocochlear nerve and is a rare intracranial tumor. The presenting complaints of a 57-year-old man who had been referred to the ENT outpatient department from a primary care provider for evaluation and management of left side vestibular schwannoma discovered on computerized tomography scan brain were insidious onset of hearing loss for the last 4 years, headache for the last 1 year which has worsened for the last 2 months and associated with vomiting episodes, along with imbalance while walking. The patient’s symptoms, tumor size, growth rate, age, and life expectancy determine the treatment of vestibular schwannoma. The above patient was advised surgery along with magnetic resonance imaging brain and preoperative investigations which the patient has agreed to do at a higher referral center of his choice.

The Impact of Social Determinants of Health on Vestibular Schwannoma Management: A Single Institution Review.

To evaluate social determinants of health and their effect on the management of vestibular schwannoma (VS). Retrospective chart review. Tertiary referral center. Patients >18 years old with sporadic VS newly diagnosed between January 1, 2010, and December 31, 2020. Magnetic resonance imaging; audiogram; treatment recommendations. Differences in treatment recommendations for patients based on their social determinants of health, including race, ethnicity, and socioeconomic status. A total of 811 patients were included in analysis. Patients with a higher area deprivation index (ADI) presented with larger tumors. A higher ADI was associated with a higher likelihood of recommending radiation (or the option of surgery or radiation) compared with a recommendation of surgery alone. Tumor grade and patient age were significantly associated with treatment recommendation. Older age was associated with a recommendation of observation alone or a recommendation of radiation. Higher tumor grade was associated with a recommendation of surgery. There was a trend for higher hearing class to be associated with a recommendation of surgery, but this did not reach statistical significance. Race, ethnicity, and gender were not significantly associated with treatment recommendation. Patients with higher levels of disadvantage presented with higher tumor grade, suggesting that access to care influences diagnosis. Factors including age, ADI, and tumor grade were associated with treatment recommendation.