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PURPOSE: NF2-related schwannomatosis (NF2) is characterized by bilateral vestibular schwannomas (VS) often causing hearing and neurologic deficits, with currently no FDA-approved drug treatment. Pre-clinical studies highlighted the potential of mTORC1 inhibition in delaying schwannoma progression. We conducted a prospective open-label, phase II study of everolimus for progressive VS in NF2 patients and investigated imaging as a potential biomarker predicting effects on growth trajectory. METHODS: The trial enrolled 12 NF2 patients with progressive VS. Participants received oral everolimus daily for 52 weeks. Brain imaging was obtained quarterly. As primary endpoint, radiographic response (RR) was defined as ≥ 20% decrease in target VS volume. Secondary endpoints included other tumors RR, hearing outcomes, drug safety and quality of life (QOL). RESULTS: Eight participants completed the trial and four discontinued the drug early due to significant volumetric VS progression. After 52 weeks of treatment, the median annual VS growth rate decreased from 77.2% at baseline to 29.4%. There was no VS RR and 3 of 8 (37.5%) participants had stable disease. Decreased or unchanged VS volume after 3 months of treatment was predictive of stabilization at 12 months. Seven of eight participants had stable hearing during treatment except one with a decline in word recognition score. Ten of twelve participants reported only minimal changes to their QOL scores. CONCLUSIONS: Volumetric imaging at 3 months can serve as an early biomarker to predict long-term sensitivity to everolimus treatment. Everolimus may represent a safe treatment option to decrease the growth of NF2-related VS in patients who have stable hearing and neurological condition. TRN: NCT01345136 (April 29, 2011).

BACKGROUND: The choice of an appropriate strategy for intracanalicular vestibular schwannoma (ICVS) is still debated. We conducted a systematic review and meta-analysis with the aim to compare treatment outcomes amongst management strategies (conservative surveillance (CS), microsurgical resection (MR), or stereotactic radiosurgery (SRS)) aiming to inform guideline recommendations on behalf of the International Stereotactic Radiosurgery Society (ISRS). METHODS: Using PRISMA guidelines, we reviewed manuscripts published between January 1990 and October 2021 referenced in PubMed or Embase. Inclusion criteria were peer-reviewed clinical studies or case series reporting a cohort of ICVS managed with CS, MR, or SRS. Primary outcome measures included tumor control, the need for additional treatment, hearing outcomes, and posttreatment neurological deficits. These were pooled using meta-analytical techniques and compared using meta-regression with random effect. RESULTS: Forty studies were included (2371 patients). The weighted pooled estimates for tumor control were 96% and 65% in SRS and CS series, respectively (P

Background: Facial palsy after vestibular schwannoma surgery is temporary in many cases but can significantly affect patients' quality of life. Physical training—initially guided and subsequently performed by the patient—is of paramount importance for recovery of facial nerve function. The introduction of medical application software (apps) might improve therapy by maintaining motivation for daily home-based training and surveilling patients' rehabilitation progress. Methods: We developed a mobile app, "FACEsemper", for home-based facial nerve rehabilitation. This app guides patients through a daily training program comprising six variable exercises, each performed in three repetitions. The app allows the user to customize the exercise intensity for different facial areas and includes a reminder function for daily training. Additional features include photo documentation, a calendar function, training report generation, and the possibility of direct communication with the attending physician. The app's usability was prospectively investigated with 27 subjects, including 8 physicians, 9 patients with facial palsy and 10 healthy subjects, over a two-week period. Usability was assessed using various self-rating questionnaires (i.e., mHealth App Usability Questionnaire, MAUQ; System Usability Scale, SUS; Visual Aesthetics of Apps Inventory, VisAAI) and scores were compared across the groups. Results: The participants reported an average smartphone use of 12.19 years and completed a mean number of 290 ± 163 facial exercises during the study period. Patients used the app significantly more frequently than the other two groups (p = 0.017). The average total scores of the questionnaires were: MAUQ 5.67/7, SUS 89.6/100, VisAAI 5.88/7 and specific rating 6.13/7. In particular, the simplicity of use and craftsmanship of the app were rated very highly. Usability scores did not significantly differ between groups. A primary limitation identified was malfunction of the daily reminder feature in some Android versions. Conclusion: This usability study demonstrated a positive user experience and excellent usability of the FACEsemper app. However, some limitations and areas for improvement were identified. As a next step, the app should be evaluated in a large patient cohort with facial palsy to determine its potential medical benefits for facial rehabilitation compared to traditional training methods. [ABSTRACT FROM AUTHOR]

Background: Ruptured pseudoaneurysm of the distal anterior inferior cerebellar artery (AICA) in patients with a history of gamma knife surgery (GKS) for vestibular schwannoma (VS) is rare. Several previous reports have described treatment strategies for radiation-induced pseudoaneurysm in the AICA: either surgical trapping or endovascular parent artery occlusion of the AICA. Methods: We present the first case of endosaccular coil embolization for a ruptured pseudoaneurysm in a large-diameter AICA after GKS for VS, successfully preserving the parent AICA. Results: Major recanalization of the coiled pseudoaneurysm was observed on follow-up imaging 3 months after the initial endovascular treatment. The patient subsequently underwent additional endosaccular coil embolizations for regrowth of the treated pseudoaneurysm buried in the VS. Two years later, another major recanalization was detected, prompting further retreatment. Subsequently, the patient has remained in a stable condition for 4 years. Conclusions: We suggest that endosaccular coil embolization of the distal AICA aneurysm with parent artery preservation might be a safe and feasible treatment option for radiation-induced saccular pseudoaneurysm arising from a large parent artery. However, close and regular follow-up imaging and preparation for potential retreatment are necessary, as pseudoaneurysms coiled within VSs are prone to recanalization. [ABSTRACT FROM AUTHOR]

Objective: The aim of this observational retrospective study was to report quality of life (QoL) in patients with postoperative facial nerve (FN) palsy after vestibular schwannoma (VS) surgery, investigating clinical factors related to functional outcomes. Methods: Forty-eight consecutive patients (M:F 25:23; median age: 52.5 years) with facial palsy following surgery for sporadic VS were considered retrospectively. FN palsy was graded by using the Sunnybrook facial grading system (SBFGS), while postoperative QoL and subjective functional aspects were assessed by using the Penn Acoustic Neuroma Quality of Life (PANQOL) Scale, the Synkinesis Assessment Questionnaire, and questions on eating and drinking. Results: A significant correlation emerged between all Sunnybrook scores and median PANQOL domain regarding facial function. Increasing overall SBFGS scores were associated with reduced risk of slow chewing on the affected side (p = 0.004), lack of masticatory strength (p = 0.025), masticatory fatigue (p < 0.001), accumulation of food in the oral vestibule (p < 0.001), difficulty in drinking from a glass (p = 0.019), and fluid spillage while drinking (p = 0.016). Conclusions: This study suggests that the clinical evaluation of patients with FN palsy after VS surgery should be integrated with patient reports about functional outcomes and perceived QoL to help clinicians guide rehabilitation choices. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigates predictors influencing the growth of untreated vestibular schwannomas, a common benign brain tumor. We aim to identify predictors of tumor growth, which is crucial for making informed treatment decisions. We reviewed numerous studies and analyzed variables such as age, gender, tumor size, location, symptoms, and MRI signal characteristics. The findings reveal that larger tumor size, extra-canalicular location, cystic components, and vestibular symptoms are associated with tumor growth. These insights can guide clinicians in identifying patients who may benefit from more aggressive monitoring or intervention, potentially improving outcomes for individuals with this condition. This research contributes to better understanding the variability in vestibular schwannoma (VS) growth and emphasizes the importance of personalized treatment strategies. The growth rate of sporadic VS varies considerably, posing challenges for consistent clinical management. This systematic review examines data on factors associated with VS growth, following a protocol registered in the PROSPERO database. The analysis reveals that key predictors of tumor growth include tumor location, initial size, and specific clinical symptoms such as hearing loss and imbalance. Additionally, several studies suggest that growth observed within the first year may serve as an indicator of subsequent progression, enabling the earlier identification of high-risk cases. Emerging factors such as the posture swing test and MRI signal intensity have also been identified as novel predictors that could further refine growth assessments. Our meta-analysis confirms that tumor location, initial size, cystic components, and vestibular symptoms are closely linked to the likelihood of VS growth. This review provides valuable guidance for clinicians in identifying patients who may require closer monitoring or early intervention. By integrating these predictive factors into clinical practice, this review supports more personalized treatment and contributes to the development of more accurate prognostic models for managing untreated sporadic VS. [ABSTRACT FROM AUTHOR]

Purpose: For patients with vestibular schwannomas (VS), a conservative observational approach is increasingly used. Therefore, the need for accurate and reliable volumetric tumor monitoring is important. Currently, a volumetric cutoff of 20% increase in tumor volume is widely used to define tumor growth in VS. The study investigates the tumor volume dependency on the limits of agreement (LoA) for volumetric measurements of VS by means of an inter-observer study. Methods: This retrospective study included 100 VS patients who underwent contrast-enhanced T1-weighted MRI. Five observers volumetrically annotated the images. Observer agreement and reliability was measured using the LoA, estimated using the limits of agreement with the mean (LOAM) method, and the intraclass correlation coefficient (ICC). Results: The 100 patients had a median average tumor volume of 903 mm3 (IQR: 193–3101). Patients were divided into four volumetric size categories based on tumor volume quartile. The smallest tumor volume quartile showed a LOAM relative to the mean of 26.8% (95% CI: 23.7–33.6), whereas for the largest tumor volume quartile this figure was found to be 7.3% (95% CI: 6.5–9.7) and when excluding peritumoral cysts: 4.8% (95% CI: 4.2–6.2). Conclusion: Agreement limits within volumetric annotation of VS are affected by tumor volume, since the LoA improves with increasing tumor volume. As a result, for tumors larger than 200 mm3, growth can reliably be detected at an earlier stage, compared to the currently widely used cutoff of 20%. However, for very small tumors, growth should be assessed with higher agreement limits than previously thought. [ABSTRACT FROM AUTHOR]

Purpose: The retrolabyrinthine approach is a surgical method designed to preserve hearing after surgery. When paired with intraoperative monitoring and an endoscope, this approach has demonstrated high rates of postoperative hearing preservation. However, the long-term prognosis of hearing preservation after utilizing this approach for vestibular schwannomas remains unexplored. This study aimed to examine the long-term outcomes of preserved hearing, providing insights into the suitability of the retrolabyrinthine approach for hearing preservation surgery. Methods: This study included 34 patients with preserved hearing after vestibular schwannoma surgery using the retrolabyrinthine approach at a single center. Long-term hearing prognosis and requirement for additional interventions were retrospectively examined. Results: Immediate after post-operative hearing preservation rate was 71.7%. Among the 34 patients with preserved hearing post-vestibular schwannoma surgery, four (11.8%) required additional interventions. Other patients experienced a gradual deterioration in their hearing status, with an approximate 10 dB decline during the 5-year follow-up; however, a serviceable hearing level persisted long after the surgery in these individuals. Conclusions: This study indicated the rationale for the retrolabyrinthine approach as a hearing preservation surgery for vestibular schwannomas, emphasizing its long-term hearing prognosis. [ABSTRACT FROM AUTHOR]

Both vestibular schwannoma (VS) and Meniere's disease (MD) patients underwent hydrops MRI to clarify the relationship between VS and endolymphatic hydrops (EH). Eighty patients with VS or MD underwent an inner ear test battery followed by hydrops MRI, and were then divided into 3 groups. Group A comprised 58 MD patients (62 ears) with positive EH but negative VS. Group B included 18 VS patients (18 ears) with negative EH, while Group C consisted of 4 patients (4 ears) who had VS concomitant with EH. Another 14 MD patients who tested negative for EH on hydrops MRI were initially excluded from this cohort, but were later included for comparison. The decreasing prevalence of EH at the cochlea, saccule and utricle in Group A was identified in 59 (95%), 42 (68%) and 40 (65%) ears, respectively, mimicking a declining sequence of abnormality rates running from audiometry (86%), cervical vestibular-evoked myogenic potential (cVEMP) test (55%) to the ocular (oVEMP) test (53%). However, such decreasing trend was not identified in Groups B and C. In Groups C and A combined, 4 (6%) of 62 EH patients had concomitant VS. Conversely, 4 (18%) of 22 VS patients in Groups C and B combined had concurrent EH. A very low (6%) rate of VS in EH patients indicates that VS in EH patients may be coincidental. In contrast, EH was identified in 18% prevalence of VS patients, mirroring the 22% prevalence of cochlear EH demonstrated in VS donors through histopathological studies. [ABSTRACT FROM AUTHOR]

Background: Fibrous dysplasia (FD) is a rare hereditary bone disorder, typically accompanied by a seemingly-high percentage of cystic changes in central nerve system tumors. This study aimed to investigate the associations between concurrent FD lesions and the cystic formation of vestibular schwannoma (VS). Methods: Patients with VSs in our institution from January 2020 to September 2022 were retrospectively included. Based on the contrasted MRI, VSs were grouped as the cystic and solid type. Concurrent FD was diagnosed based on the radiological findings. A logistic analysis was applied to investigate the relationship between concurrent FD and cystic VSs. The effect of the interaction between gender and concurrent FD on the cystic formation of VSs was further analyzed. Results: The current study included 1255 patients with VSs (681 females with a median age of 47 years). Of them, 142 (11.3%) were with cystic VSs. A higher percentage of cystic VSs was observed in female patients (P = 0.021), patients with concurrent FDs (P < 0.001) and those with a larger VS volume (P < 0.001). An increasing trend in percentage of cystic VSs was found among patients with from 0 to ≥ 3 FD lesions (P for trend as < 0.001). A multivariate logistic analysis identified concurrent FD (odds ratio, 6.58; 95%CI, 1.66–26.09; P = 0.007) and VS volume (odds ratio, 1.55; 95%CI, 1.66–1.70; P < 0.001) as independent risk factors related to the cystic formation. Conclusion: Concurrent FD is associated with a high incidence of cystic formation in VSs, which provides a new breakthrough point to investigate the underlying mechanism of cystic formation of VSs. [ABSTRACT FROM AUTHOR]

The removal of vestibular schwannomas carries a risk of facial palsy. This study aims to evaluate the usefulness and technical aspects of intraoperative monitoring (IOM) for the facial nerve. A total of 96 patients who underwent surgery for vestibular schwannoma were retrospectively investigated. The cohort was divided into two groups: those with intraoperative facial nerve monitoring (IOM group) and those without IOM (non-IOM group). Preoperative and postoperative facial nerve functions were assessed using the House-Brackmann (HB) scale immediately after surgery, at discharge, and at the 1-year follow-up. HB grade I and II were classified as satisfactory outcomes, HB grade III and IV as intermediate, and HB grade V and VI as poor. Facial nerve functions were compared between the groups. Additionally, the ratio of satisfactory results was investigated in the IOM group, focusing on whether the root exit zone (REZ) was identified at an early or late stage of surgery. Among the 65 (67%) patients in the IOM group and 31 (32%) patients in the non-IOM group, there were no differences in demographic and tumor characteristics. The extent of resection varied from subtotal to gross total removal, with no statistical differences between the groups. Although facial nerve function was more favorably preserved in the non-IOM group immediately after surgery, this trend reversed at discharge and the 1-year follow-up, showing significant statistical differences. In the IOM group, more patients achieved satisfactory outcomes when the REZ was identified early compared to late during tumor resection. Intraoperative facial nerve monitoring provides more satisfactory outcomes in preserving nerve function in vestibular schwannoma surgery. Early recognition of the REZ may contribute to improved surgical outcomes. [ABSTRACT FROM AUTHOR]

Objective Despite advances in skull-base reconstruction techniques, cerebrospinal fluid (CSF) leaks remain a common complication following retrosigmoid (RS) vestibular schwannoma (VS) surgery. We aimed to review and classify the available strategies used to prevent CSF leaks following RS VS surgery. Methods A systematic review, including studies of adults undergoing RS VS surgery since 2000, was conducted. Repair protocols were synthesized into a narrative summary, and a taxonomic classification of techniques and materials was produced. Additionally, the advantages, disadvantages, and associated CSF leak rates of different repair protocols were described. Results All 42 studies were case series, of which 34 were retrospective, and eight were prospective. Repair strategies included heterogeneous combinations of autografts, xenografts, and synthetic materials. A repair taxonomy was produced considering seven distinct stages to CSF leak prevention, including intraoperative approaches to the dura, internal auditory canal (IAC), air cells, RS bony defect, extracranial soft tissue, postoperative dressings, and CSF diversion. Notably, there was significant heterogeneity among institutions, particularly in the dural and IAC stages. The median postoperative incidence of CSF leaks was 6.3% (IQR: 1.3–8.44%). Conclusions The intraoperative strategies used to prevent CSF leaks during RS VS surgery vary between and within institutions. As a result of this heterogeneity and inconsistent reporting of CSF leak predictive factors, a meaningful comparative analysis of repair protocols was not feasible. Instead, we propose the development of a prospective multicenter observational evaluation designed to accurately capture a comprehensive dataset of potential CSF risk factors, including all stages of the operative repair protocol. [ABSTRACT FROM AUTHOR]

Objectives Despite advances in skull base reconstruction techniques, cerebrospinal fluid (CSF) leaks remain a relatively common complication after translabyrinthine (TL) vestibular schwannoma (VS) surgery. We conducted a systematic review to synthesize the repair techniques and materials used in TL VS surgery to prevent CSF leaks. Design A systematic review of studies published since 2000 reporting techniques to prevent CSF leaks during adult TL VS surgery was conducted. A narrative synthesis of primary repair protocols was produced, and a taxonomy was established. Additionally, the advantages, disadvantages, and associated CSF leak rates of different repair protocols were extracted. Results All 43 studies were case series, and 39 were retrospective. Repair strategies included heterogeneous combinations of autografts, xenografts, and synthetic materials. A taxonomy was produced, classifying repairs into seven distinct stages, including approaches to the dura, middle ear cleft, air cells, TL bony defect, extra-cranial soft tissue, postoperative dressings, and CSF diversion. The median postoperative incidence of CSF leaks was 6% (interquartile range: 0–10%). Conclusions This systematic review reveals substantial inter-institutional heterogeneity in intraoperative strategies to prevent CSF leaks following TL VS surgery. However, comparing these techniques is challenging due to the multiple predictive factors for CSF leaks and their inconsistent reporting. We propose a taxonomy of seven stages to classify operative techniques and materials aimed at preventing CSF leaks. We recommend that future evaluations should adopt a prospective approach encompassing data collection strategies that considers all operative stages described by our taxonomy. [ABSTRACT FROM AUTHOR]

Objective The aims of the study are (1) to evaluate the extended middle fossa approach (eMCF) for resection of tumors in the petroclivus and anterior cerebellopontine angle (CPA) and (2) to compare surgical outcomes between elderly (≥65 years) and nonelderly patients. Design Retrospective cohort. Setting Tertiary referral center. Participants Adults with petroclival, anterior CPA, or posterior fossa lesions who underwent an eMCF approach from 2012 to 2021 were included in the study. Main Outcome Measure Demographics, symptoms, cranial nerve (CN) function, and postoperative outcomes. Results Twenty-nine patients (mean age of 55 years, 59% females) were identified. Eleven (38%) were ≥65 years (65–79 years). The most common pathology was meningioma (n = 13, 45%), followed by vestibular schwannoma (n = 4, 14%) and squamous cell carcinoma (n = 3, 10%). Nineteen tumors (65.5%) were located in the petroclivus, 7 (24%) involved the cavernous sinus, and 10 (34%) were located in the posterior fossa. The mean tumor maximal diameter was 3.4 cm (range: 1.3–7.9 cm). Gross total tumor resection was accomplished in 15 (52%) patients. Most patients (n = 23, 79%) did not develop new CN deficits postoperatively. Of the 13 patients who had complete pre- and postoperative audiometric data, 69% (n = 9) maintained their hearing. Comparing the elderly versus nonelderly patients, there were no significant differences in the development of new CN palsies (p = 0.14), length of stay (p = 0.91), or incidence of postoperative complications (p = 0.30). Conclusions The eMCF approach provides exposure to the petroclival region, anterior CPA cistern, and posterior fossa for a variety of pathologies. It has a favorable safety profile in the elderly (≥65 years) population with low morbidity. [ABSTRACT FROM AUTHOR]

Objectives To assess whether vestibular prehabilitation with intratympanic gentamicin is a useful preoperative adjunct in allowing for early mobilization and short length of stay in patients with vestibular schwannoma (VS). Design Retrospective single-center study and literature review. Setting Tertiary neurosurgical center. Participants Adult patients undergoing surgery for VS. Main Outcome Measures Our primary outcome measures were evidence of compensation following prehabilitation (defined as saccades becoming more covert and clustered on video head impulse testing—vHIT), length of stay, and days until mobilization. Secondary outcome measures were reduction in gain on vHIT following treatment as well as need for antiemetics postoperatively. Results Ten patients have been treated at our center and the majority have shown preoperative reduction in gain and evidence of compensation on vHIT. Median time to mobilization was 1 day and modal length of stay was 6 days. We found the current evidence to be variable, with small sample sizes and significant variation in outcome measures used. Conclusion Overall we have found that the use of vestibular prehabilitation enables early mobilization, shortened length of stay and appears to be a promising preoperative adjunct in this population. Further research and assessment with a multicenter prospective clinical trial is merited. [ABSTRACT FROM AUTHOR]

The introduction of the electronic health record (EHR) has improved the collection and storage of patient information, enhancing clinical communication and academic research. However, EHRs are limited by data quality and the time-consuming task of manual data extraction. This study aimed to use process mapping to help identify critical data entry points within the clinical pathway for patients with vestibular schwannoma (VS) ideal for structured data entry and automated data collection to improve patient care and research. A 2-stage methodology was used at a neurosurgical unit. Process maps were developed using semi-structured interviews with stakeholders in the management of VS resection. Process maps were then retrospectively validated against EHRs for patients admitted between August 2019 and December 2021, establishing critical data entry points. In the process map development, 20 stakeholders were interviewed. Process maps were validated against EHRs of 36 patients admitted for VS resection. Operative notes, surgical inpatient reviews (including ward rounds), and discharge summaries were available for all patients, representing critical data entry points. Areas for documentation improvement were in the preoperative clinics (30/36; 83.3%), preoperative skull base multidisciplinary team (32/36; 88.9%), postoperative follow-up clinics (32/36; 88.9%), and postoperative skull base multidisciplinary team meeting (29/36; 80.6%). This is a first use to our knowledge of a 2-stage methodology for process mapping the clinical pathway for patients undergoing VS resection. We identified critical data entry points that can be targeted for structured data entry and for automated data collection tools, positively impacting patient care and research. [ABSTRACT FROM AUTHOR]

Background: Surgical resection of vestibular schwannomas (VS) can be responsible for single-sided deafness (SSD). Hearing restoration can be a challenge both for the otolaryngologist and the patient. Patients and Methods: In a retrospective series, we analyzed the charts of SSD patients operated on for VS from 2005–2021, checking which type of hearing rehabilitation was chosen. All patients who wanted a hearing restoration underwent a hearing in noise test (HINT) in a stereo auditorium with and without a bone-anchored hearing device (BAHD) worn with a headband on the deaf side. Then, they had a preimplantation one-month trial with the BAHD at home vs. contralateral routing of signal (CROS) or BiCROS (with contralateral signal amplification) hearing aids (HAs). Results: Among 52 charts of the included adult SSD patients, only 29 (56%) eventually chose a hearing rehabilitation device (14 BAHD). Only one BAHD patient required a device explantation for skin complications, but then asked for reimplantation. Another one swapped the BAHD for HAs 2.5 years after. Two patients only occasionally used their BAHD with a headband. Nine patients preferred HAs, mainly BiCROS. Their contralateral hearing was significantly less than BAHD patients (p < 0.05), and only three used their HAs every day. Conclusions: Hearing rehabilitation in SSD patients after VS surgical resection is chosen in about 50% of cases. In complement of HINT, a real-life comparative hearing trial helps patients chose the best device, with good long-term results when a BAHD is chosen. HAs are preferred when contralateral hearing is altered but are not always worn. [ABSTRACT FROM AUTHOR]

Background/Objectives: Obstructive hydrocephalus associated with vestibular schwannoma (VS) is the most common in giant VS. Despite tumor removal, some patients may require ongoing ventriculo-peritoneal (VP) surgery. This investigation explores the factors contributing to the requirement for VP surgery following VS surgery in instances of persistent hydrocephalus (HCP). Methods: Volumetric MRI analyses of pre- and postoperative tumor volumes, cerebellum, cerebrum, ventricle system, fourth ventricle, brainstem, and peritumoral edema were conducted using Brainlab Smartbrush and 3D Slicer. The total brain volume was defined as the sum of the cerebrum, cerebellum, and brainstem. ROC analyses were performed to identify the optimum cut-off values of the volumetric data. Results: Permanent cerebrospinal fluid (CSF) diversion after surgery was indicated in 12 patients (12/71; 16.9%). The ratio of baseline volume fraction of brain ventricles to total brain ventricle volume (VTB ratio) was found to predict postoperative VP shunt dependency. The AUC was 0.71 (95% CI: 0.51–0.91), and the optimum threshold value (

Cancer-associated fibroblast (CAF) composition within the same organ varies across different cancer subtypes. Distinct CAF subtypes exhibit unique features due to interactions with immune cells and the tumor microenvironment. However, data on CAF subtypes in individuals with vestibular schwannoma (VS) are lacking. Therefore, we aimed to distinguish CAF subtypes at the single-cell level, investigate how stem-like CAF characteristics influence the tumor immune microenvironment, and identify CAF subtype-specific metabolic reprogramming pathways that contribute to tumor development. Data were analyzed from three patients with VS, encompassing 33,081 single cells, one bulk transcriptome cohort, and The Cancer Genome Atlas Pan-Cancer database (RNA sequencing and clinical data). Our findings revealed that antigen-presenting CAFs are linked to substantially heightened immune activity, supported by metabolic reprogramming, which differs from tumorigenesis. High expression of the stem-like CAF gene signature correlated with poor prognosis in low-grade gliomas within the pan-cancer database. This is the first study to classify CAF subtypes in VS patients and identify a therapeutic vulnerability biomarker by developing a stem-like CAF gene signature. Personalized treatments tailored to individual patients show promise in advancing precision medicine. [ABSTRACT FROM AUTHOR]

Purpose: This retrospective monocentric study aimed to evaluate long-term auditory brainstem implant (ABI) function in patients with neurofibromatosis type 2, and to investigate the prognostic factors for ABI use. Methods: Between 1997 and 2022, 27 patients with at least five years of follow-up underwent implantation with 32 ABIs. At 1- and 5-years post-implantation and at last follow-up, ABIs were classified as used or non-used and the size of the ipsilateral tumor was recorded. For patients who used their ABIs, we assessed speech perception (disyllabic words, MBAA sentences) in quiet conditions with the ABI only, by lip-reading (LR), and with a combination of the two (ABI + LR). Hearing improvement was calculated as Δ ABI = (ABI + LR)–LR scores. Predictive factors for ABI use were analyzed. Results: One year post-implantation, 74% patients were ABI-users and 66% of the ABIs were used. Two of these patients were non-users at five years, and another two at last follow-up (14 ± 5.2 years); 54% of the patients were ABI-users at last follow-up. Δ ABI revealed a hearing improvement of 32–41% (disyllabic words) and 28–37% (MBAA sentences). Among 16 ABIs with at least LR improvement at 1-year post-implantation, 4 decreased their performance, coinciding with a large growing ipsilateral tumor in 3/4 ABIs. We identified no significant prognostic factors for ABI use. Conclusions: ABIs are indicated in case of bilateral deafness with a non-functional cochlear nerve. Half the patients with ABIs used their implants and auditory performance remained stable over time, except in cases of ipsilateral tumor growth. [ABSTRACT FROM AUTHOR]

Purpose: The internal auditory canal (IAC) plays a key role in lateral skull base surgery. Although several approaches to the IAC have been proposed, endoscope-assisted transcanal corridors to the IAC have rarely been studied. We sought to provide a step-by-step description of the transcanal transpromontorial approach to the IAC and analyze anatomic relationships that might enhance predictability and safety of this approach. Methods: Ten cadaveric specimens were dissected and the extended transcanal transpromontorial approach to the IAC was established. Various morphometric measurements and anatomic landmarks were reviewed and analyzed. Results: The proposed technique proved feasible and safe in all specimens. There was no inadvertent injury to the jugular bulb or internal carotid artery. The chorda tympani, a key landmark for the mastoid segment of the facial nerve, was identified in all dissections. The spherical recess of the vestibule and middle turn of cochlea are important landmarks for identification of the labyrinthine segment of the facial nerve. Identification of all boundaries of the working area is also essential for safe access. Among various morphometric measurements, the modiolus-IAC angle (≈ 150°) proved particularly consistent; given its ease of use and low variability, we believe it could serve as a landmark for identification and subsequent dissection of the IAC. Conclusions: The extended transcanal transpromontorial approach to the IAC is feasible and safe. Relying on anatomic landmarks to ensure preservation of the involved neurovascular structures is essential for a successful approach. The modiolus-IAC angle is a consistent, reproducible landmark for IAC identification and dissection. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to assess the ability to smile following a hypoglossal–facial nerve transfer (N12–N7). Design This is a retrospective chart review. Setting National tertiary referral center for skull base pathology. Participants Seventeen patients. Main Outcome Measures The ability to smile following an N12–N7 transfer was assessed by five medical doctors on photographs of the whole face and frontal, orbital, and oral segments. The (segmented) photographs were scored for the symmetry, asymmetry, and correct or incorrect assessment of the affected side. Results Seventeen patients were analyzed by 5 assessors providing 85 assessments. The whole face at rest was judged symmetrical in 26% of the cases and mildly asymmetrical in 56%. Frontal, orbital, and oral segments were symmetrical in 63, 20, and 35%, respectively. The affected side was correctly identified in 76%. When smiling, the whole face was symmetrical in 6% and mildly asymmetric in 59%. The affected side was correctly identified in 94%. The frontal, orbital, and oral segments during smiling were symmetrical in 67, 15, and 6%, respectively. The affected side of the frontal, orbital, and buccal facial segments during smiling was correctly identified in 89, 89, and 96%, respectively. Interobserver variability with Fleiss' kappa analysis showed that the strength of the agreement during smile of the total face was good (0.771) Conclusion Following an N12–N7 transfer, a good facial symmetry at rest can be achieved. During smiling, almost all patients showed asymmetry of the face, which was predominantly determined by the orbital and oral segments. To improve the ability to smile after an N12–N7 transfer, additional procedures are needed. [ABSTRACT FROM AUTHOR]

Purpose: Tractography of the facial nerve based on diffusion MRI is instrumental before surgery for the resection of vestibular schwannoma, but no excellent methods usable for the suppression of motion and image noise have been proposed. The aim of this study was to effectively suppress noise and provide accurate facial nerve reconstruction by extend a fiber trajectory distribution function based on the fourth‐order streamline differential equations. Methods: Preoperative MRI from 33 patients with vestibular schwannoma who underwent surgical resection were utilized in this study. First, T1WI and T2WI were used to obtain mask images and regions of interest. Second, probabilistic tractography was employed to obtain the fibers representing the approximate facial nerve pathway, and these fibers were subsequently translated into orientation information for each voxel. Last, the voxel orientation information and the peaks of the fiber orientation distribution were combined to generate a fiber trajectory distribution function, which was used to parameterize the anatomical information. The parameters were determined by minimizing the cost between the trajectory of fibers and the estimated directions. Results: Qualitative and visual analyses were used to compare facial nerve reconstruction with intraoperative recordings. Compared with other methods (SD_Stream, iFOD1, iFOD2, unscented Kalman filter, parallel transport tractography), the fiber‐trajectory‐distribution‐based tractography provided the most accurate facial nerve reconstructions. Conclusion: The fiber‐trajectory‐distribution‐based tractography can effectively suppress the effect of noise. It is a more valuable aid for surgeons before vestibular schwannoma resection, which may ultimately improve the postsurgical patient's outcome. [ABSTRACT FROM AUTHOR]

Purpose: Limited 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. Methods: A 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). Results: The 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. Conclusions: Repeat GKRS effectively controlled tumor growth and preserved cranial nerve outcomes in most patients whose VS had sustained progression after initial primary radiosurgery. [ABSTRACT FROM AUTHOR]

Background: Facial nerve paralysis is a severe dysfunction after vestibular schwannoma (VS) surgery. Methods: This monocentric study analyzed 61 patients who underwent sporadic VS surgery in a standardized manner. The primary endpoint was the facial nerve outcome (FNO) at 3 months after VS surgery. FNO was dichotomized into "good" (House–Brackmann (HB) score ≤ 2) and "poor" (HB > 2). Results: Poor FNO was observed in 11 patients (18.0%) at 3 months after VS surgery. Radiomic tumor shape features were analyzed, and the AUC of elongation in the prediction of a poor HB at 3 months was 0.70 (95% CI: 0.56–0.85, p = 0.03) and the optimum threshold value (≤/>0.35) yielded a sensitivity and specificity of 64.0% and 75.4%, respectively. Multivariable logistic regression analyses considering the extent of resection (0.35) revealed that more elongated VSs (≤0.35; OR: 5.8; 95%CI: 1.2–28.2; p = 0.03) and those with an increased EoR (≥93.4%; OR: 6.5; 95%CI: 1.0–42.5; p = 0.05) are independently associated with poorer FNO at 3 months after surgery. Conclusions: Highly elongated VS shape seems to be a risk factor for worsened facial nerve outcome at 3 months after surgery for Koos grade 3 and 4 tumors. [ABSTRACT FROM AUTHOR]

Simple Summary: The mechanisms underlying the size progression of vestibular schwannomas remain poorly understood. Accordingly, this study was focused on investigating the potential role of messenger substances in regulating the growth of these tumors. These cytokines are produced by the tumor cells themselves or by other cells, such as immune cells. The influence of the cytokines on the size progression of tumors could facilitate the development and establishment of drug therapies for vestibular schwannoma patients, which are currently unavailable for sporadic vestibular schwannomas. Sporadic vestibular schwannomas (VSs) often exhibit slow or negligible growth. Nevertheless, some VSs increase significantly in volume within a few months or grow continuously. Recent evidence indicates a role of inflammation in promoting VS growth. Therefore, our study aimed to identify cytokines, which are associated with larger VSs. The expression of different cytokines in VS tumor samples and VS primary cultures was investigated. Additionally, the concentration of cytokines in cell culture supernatants of VS primary cultures and cerebrospinal fluid (CSF) of VS patients and healthy controls were determined. Correlation analysis of cytokine levels with tumor volume, growth rate, Koos grade, age, and hearing was examined with Spearman's-rank test. The mRNA expression of CC-chemokine ligand (CCL) 18, growth differentiation factor (GDF) 15, and interferon regulatory factor 4 correlated positively with tumor volume. Moreover, the amount of GDF15 in the cell culture supernatant of primary cells correlated positively with tumor volume. The concentrations of the cytokines CCL2, CCL5, and CCL18 and transforming growth factor beta (TGFB) 1 in the CSF of the patients were significantly different from those in the CSF controls. Inhibition of immune cell infiltration could be a putative approach to prevent and control VS growth. [ABSTRACT FROM AUTHOR]

A schwannoma is a nerve sheath tumor that is formed by Schwann cells. Vestibular schwannomas are thought to account for the majority of intracranial schwannomas. Nonvestibular schwannomas account for about 10%, about half of which are trigeminal schwannomas. Multiple intracranial schwannomas originating from different cranial nerves are extremely rare. We describe the clinical case of a 42-year-old female patient with vestibular schwannoma and multiple trigeminal schwannomas. That case shows how multiple trigeminal schwannomas were identified intraoperatively during elective surgery for vestibular schwannoma removal, most of which were resected. No new neurological deficits were observed in the patient. The presence of multiple intracranial schwannomas is extremely rare in neurosurgical practice and can change the intraoperative strategy and the course of the surgery. [ABSTRACT FROM AUTHOR]

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Purpose: It has been shown that in large vestibular schwannomas (VS), radiosurgery (SRS) is inferior with respect to tumor control compared to microsurgical resection (SURGERY). However, SURGERY poses a significantly higher risk of facial-function deterioration (FFD). The aim of this study was to illustrate the effectiveness in terms of number-needed-to-treat/operate (NNO), number-needed-to-harm (NNH), and likelihood-of-harm/help (LHH) by comparing both treatment modalities in large VS. Methods: This was a retrospective, dual-center cohort study. Tumor size was classified by Hannover Classification. Absolute risk reduction and risk increase were used to derive additional estimates of treatment effectiveness, namely NNO and NNH. LHH was then calculated by a quotient of NNH/NNO to illustrate the risk–benefit-ratio of SURGERY. Results: Four hundred and forty–nine patients treated met the inclusion criteria. The incidence of tumor recurrence was significantly higher in SRS (14%), compared to SURGERY (3%) resulting in ARR of 11% and NNO of 10. At the same time, SURGERY was related to a significant risk of FFD resulting in an NNH of 12. Overall, the LHH calculated at 1.20 was favored SURGERY, especially in patients under the age of 40 years (LHH = 2.40), cystic VS (LHH = 4.33), and Hannover T3a (LHH = 1.83) and T3b (LHH = 1.80). Conclusions: Due to a poorer response of large VS to SRS, SURGERY is superior with respect to tumor control. One tumor recurrence can be prevented, when 10 patients are treated by SURGERY instead of SRS. Thus, LHH portrays the benefit of SURGERY in large VS even when taking raised FFD into account. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of wait and scan (W&S) and stereotactic radiosurgery (SRS) on health‐related quality of life (HRQoL) over time in patients with a stable vestibular schwannoma (VS) and growing VS. Study Design: Longitudinal, multicenter, observational study. Setting: Tertiary expert center for VS (Radboudumc Nijmegen) and Gamma‐Knife center ETZ Hospital Tilburg. Methods: Changes in HRQoL, measured with the Penn Acoustic Neuroma Quality‐of‐Life (PANQOL), and the physical and mental component summary scores (PCS and MCS, respectively) derived from the 36‐Item Short Form Health Survey (SF‐36), were compared among patients managed by W&S and SRS between 2017 and 2022. Second, HRQoL over time in patients with a growing VS was compared between W&S and SRS. Results: Differences in PANQOL total and subdomain scores, PCS and MCS scores over time in the W&S (n = 73) and SRS (n = 170) groups were nonsignificant and on average did not exceed the minimal clinically important differences (mean difference of −2.56 [PANQOL total], 1.22 [PCS], and −1.76 [MCS]; all P >.05). In growing VS, comparison of W&S (n = 29) and SRS (n = 154) also revealed no significant difference (mean difference of 1.19 (PANQOL total), 1.83 (PCS) and −0.12 (MCS); all P >.05). Conclusion: Differences in HRQoL in patients with VS are minor and not significantly different or clinically relevant between patients managed with W&S or SRS. Similarly, patients with a growing VS managed with W&S or SRS exhibit no significant or clinical relevant difference in HRQoL during follow‐up. This can aid clinicians in the counseling of patients regarding HRQoL when deciding on a management strategy after diagnosis or documented growth. [ABSTRACT FROM AUTHOR]

Objective: To evaluate tumor control and facial nerve outcomes after gross‐total (GTR), near‐total (NTR), and subtotal resection (STR) of sporadic vestibular schwannomas (VS). Data Sources: PubMed, Cochrane Central Register of Controlled Trials, Web of Science, and Scopus databases were searched in August 2021 through inception following PRISMA guidelines. Review Methods: English language articles reporting tumor control and facial nerve outcomes of adults (≥18 years) with NTR and STR of VS were evaluated. Study characteristics, demographics data, tumor characteristics, type of surgical intervention, and outcome measures on tumor control and facial nerve function were collected. Pooled relative risk (RR) estimates for tumor recurrence and facial nerve outcomes were calculated and stratified by extent of resection. Results: From an initial search of 2504 articles, 48 studies were included in the analysis. When comparing 1108 patients who underwent NTR to 3349 patients with GTR, the pooled RR of recurrence in the NTR cohort was 2.94 (95% confidence interval [CI] 1.65‐5.24, P =.0002). When comparing 1016 patients who underwent STR to 6171 patients with GTR, the pooled RR of recurrence in the STR cohort was 11.50 (95% CI 6.64‐19.92, P <.0001). Estimates for risk of tumor regrowth for less‐than‐complete resection are presented. There was no elevated risk of adverse facial nerve outcome (defined as House‐Brackmann grade III and above) in each category of extent of resection compared to GTR. Conclusion: Extent of resection predicts risk of tumor recurrence/regrowth following microsurgical resection. Favorable facial nerve outcome should be weighed against the increased risk of regrowth and the potential need for further treatment. [ABSTRACT FROM AUTHOR]

PURPOSE: The purpose of this study is to investigate inter-planner plan quality variability using a manual forward planning (MFP)- or fast inverse planning (FIP, Lightning)-approach for single brain lesions treated with the Gamma Knife® (GK) Icon™. METHODS: Thirty patients who were previously treated with GK stereotactic radiosurgery or radiotherapy were selected and divided into three groups (post-operative resection cavity, intact brain metastasis, and vestibular schwannoma [10 patients per group]). Clinical plans for the 30 patients were generated by multiple planners using FIP only (1), a combination of FIP and MFP (12), and MFP only (17). Three planners (Senior, Junior, and Novice) with varying experience levels re-planned the 30 patients using MFP and FIP (two plans per patient) with planning time limit of 60 min. Statistical analysis was performed to compare plan quality metrics (Paddick conformity index, gradient index, number of shots, prescription isodose line, target coverage, beam-on-time (BOT), and organs-at-risk doses) of MFP or FIP plans among three planners and to compare plan quality metrics between each planners MFP/FIP plans and clinical plans. Variability in FIP parameter settings (BOT, low dose, and target max dose) and in planning time among the planners was also evaluated. RESULTS: Variations in plan quality metrics of FIP plans among three planners were smaller than those of MFP plans for all three groups. Juniors MFP plans were the most comparable to the clinical plans, whereas Seniors and Novices MFP plans were superior and inferior, respectively. All three planners FIP plans were comparable or superior to the clinical plans. Differences in FIP parameter settings among the planners were observed. Planning time was shorter and variations in planning time among the planners were smaller for FIP plans in all three groups. CONCLUSIONS: The FIP approach is less planner dependent and more time-honored than the MFP approach.

Introduction Research furthering treatment efficacy for microsurgical resection and stereotactic radiosurgery for vestibular schwannoma (VS) is ever-growing; however, there remains a paucity of research addressing treatment costs. Our aim is to define the reported costs of different treatment modalities used for VS. Methods A systematic review of the literature for VS treatment cost was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using PubMed and Web of Science databases. Literature that presented cost of VS treatment specific to the modality was included. Articles from 1990 to present day in English were considered. Cost was corrected for inflation to April 2022 dollars using the US Bureau of Labor Statistics Inflation Calculator. Results A total of 407 articles were included in the analysis. After review, eight articles provided data on cost of treatment. In total, 687 patients were included across seven studies, with study dates ranging from 1997 to 2020. The average cost of resection was $54,321.99 (range = $10,243–95,590, n = 8), radiosurgery $27,837.92 (range = $6,281–51,676, n = 6), and observation $6,304.88 (range = $2,149–11,886, n = 3). Conclusion Our findings describe the limited and significant variability of data on published costs for the treatment of VS. Given the relative clinical equipoise between treatment modalities in some scenarios, better understanding of this end-point will help physicians make more responsible recommendations in the resource-constrained environment of modern healthcare and this analysis should serve as a starting point for more robust analysis into cost-effectiveness of treatment for VS. [ABSTRACT FROM AUTHOR]

Abstract Background Vestibular schwannomas (VS) are slowly growing tumor, deriving from the vestibular component of cranial nerve VIII. Primary treatment modalities include microsurgery, radiosurgery, a combination of microsurgery and radiosurgery, and conservative treatment. The management of VS is a matter of debate, particularly in case of small tumors (less than 2 cm in diameter size). Methods We performed an institutional retrospective review of a consecutive series of 28 surgically treated patients suffering from VS, operated in our institution. Patients were assigned on the ground of the preoperative imaging in two groups: tumors with major diameter of extra-meatal portion measuring ≥ 3 cm (Group I, 16 patients) and tumors with major diameter

Abstract Background Vestibular schwannomas (VSs) are benign tumors of the vestibulocochlear nerve that often cause significant neurological and functional impairment. Patient-reported outcomes, including quality of life (QoL), are essential for understanding the overall impact of VS and its treatment. This study aimed to translate and culturally adapt the Vestibular Schwannoma Quality of Life (VSQOL) Index into German to expand its relevance to German-speaking populations. Methods We used a qualitative approach including translation and cognitive interviews with 10 patients who underwent VS surgery. The translation process followed the TRAPD protocol to ensure linguistic and conceptual accuracy. Cognitive interviews assessed the comprehensibility and relevance of the translated questionnaire. Results The translation showed remarkable consistency between translators, with minor discrepancies resolved by consensus. Cognitive interviews provided valuable insights that led to refinements in item wording. Participants emphasized the importance of an additional item on physician referrals, reflecting differences in health care systems between the United States and Germany. Conclusions The German VSQOL provides a comprehensive tool for assessing QoL in patients with VS that integrates patient-centered dimensions. A Validation study is underway to establish its reliability and validity.

Stereotactic radiosurgery (SRS) is an effective treatment for vestibular schwannomas, offering high rates of tumor control and low neurological risks. Long-term complications of SRS are not fully understood, with several cases of malignant transformation reported in the literature. We report the case of a 50-year-old female with no prior history of neurofibromatosis who presented in 2013 with MRI evidence of a benign vestibular schwannoma. Despite treatment with CyberKnife SRS, she presented 6 years later with new onset neurologic symptoms. Further investigation showed stable lesion size with increasing vasogenic edema and a new area of enhancement in the brainstem, suspicious for malignant transformation. Subsequent treatment with partial craniectomy and histopathologic analysis was consistent with a malignant peripheral nerve sheath tumor diagnosis. Our case adds to a series of 24 similar cases in the literature, details of which have been summarized in our study. Overall, findings support the need for lifelong surveillance following SRS treatment of benign vestibular schwannomas. Patients should be educated on the potential risk of this complication, and clinicians must maintain a high level of suspicion for potential radiation-induced malignancy during the patient's clinical course.

Abstract Variations in the biomechanical stiffness of brain tumors can not only influence the difficulty of surgical resection but also impact postoperative outcomes. In a prospective, single-blinded study, we utilize pre-operative magnetic resonance elastography (MRE) to predict the stiffness of intracranial tumors intraoperatively and assess the impact of increased tumor stiffness on clinical outcomes following microsurgical resection of vestibular schwannomas (VS) and meningiomas. MRE measurements significantly correlated with intraoperative tumor stiffness and baseline hearing status of VS patients. Additionally, MRE stiffness was elevated in patients that underwent sub-total tumor resection compared to gross total resection and those with worse postoperative facial nerve function. Furthermore, we identify tumor microenvironment biomarkers of increased stiffness, including αSMA + myogenic fibroblasts, CD163 + macrophages, and HABP (hyaluronic acid binding protein). In a human VS cell line, a dose-dependent upregulation of HAS1-3, enzymes responsible for hyaluronan synthesis, was observed following stimulation with TNFα, a proinflammatory cytokine present in VS. Taken together, MRE is an accurate, non-invasive predictor of tumor stiffness in VS and meningiomas. VS with increased stiffness portends worse preoperative hearing and poorer postoperative outcomes. Moreover, inflammation-mediated hyaluronan deposition may lead to increased stiffness.

Abstract This study examined the association between hearing loss in sporadic vestibular schwannoma patients and the proteome of perilymph (PL), cerebrospinal fluid (CSF), and vestibular schwannoma. Intraoperative sampling of PL and of CSF, and biopsy of vestibular schwannoma tissue, was performed in 32, 32, and 20 patients with vestibular schwannoma, respectively. Perilymph and CSF in three patients with meningioma and normal hearing were also sampled. The proteomes were identified by liquid chromatography coupled to high-resolution tandem mass spectrometry. Preoperative hearing function of the patients was evaluated with pure tone audiometry, with mean values at frequencies of 500, 1000, 2000, and 4000 Hz (PTA4) in the tumor-affected ear used to delineate three hearing groups. Analysis of the PL samples revealed significant upregulation of complement factor H-related protein 2 (CFHR2) in patients with severe to profound hearing loss after false discovery rate correction. Pathway analysis of biofunctions revealed higher activation scores in the severe/profound hearing loss group of leukocyte migration, viral infection, and migration of cells in PL. Upregulation of CFHR2 and activation of these pathways indicate chronic inflammation in the cochlea of vestibular schwannoma patients with severe to profound hearing loss compared with patients with normal hearing or mild hearing loss.

Background: Vestibular schwannomas (VS) are slowly growing tumor, deriving from the vestibular component of cranial nerve VIII. Primary treatment modalities include microsurgery, radiosurgery, a combination of microsurgery and radiosurgery, and conservative treatment. The management of VS is a matter of debate, particularly in case of small tumors (less than 2 cm in diameter size). Methods: We performed an institutional retrospective review of a consecutive series of 28 surgically treated patients suffering from VS, operated in our institution. Patients were assigned on the ground of the preoperative imaging in two groups: tumors with major diameter of extra-meatal portion measuring ≥ 3 cm (Group I, 16 patients) and tumors with major diameter < to 3 cm (Group II, 12 patients). Results: The total amount of 18/28 patients were females; the average age was 60.1 years. The average duration of the preoperative symptoms was 25.2 months, while the average interval between the diagnosis and surgical treatment was 8.68 months. The average preoperative volume was, respectively, for Group I and II tumors of 14.35 cm3 and 3.73 cm3. Age was associated to the duration of the preoperative symptoms (r = − 364; p = 0.044), with the probability to develop a complication (p = 0.031) and preoperative low HB score (r = − 324; p = 0.040). The presence of hypoacusis as preoperative symptom was strongly associated to a lesser postoperative maximum diameter and smaller residual disease (p = 0.014). Group I had a significantly longer hospitalization period in respect to Group II (p = 0.001) that impacted negatively to postoperative performance status (r = 0.368, p = 0.042). Conclusions: We confirmed the strong association between age and size of the lesion and the clinical results, where larger lesions in older patients are more prone to complications than smaller in young patients. We found that the patients presenting hypoacusis at onset were associate to lesser preoperative FN impairment outlining a possible differential involvement of the CN related to the internal meatus. We also introduce the strong association of Koos grade with postoperative performance status, hospitalization and facial nerve functionality. [ABSTRACT FROM AUTHOR]

Background: Vestibular schwannomas (VSs) are benign tumors of the vestibulocochlear nerve that often cause significant neurological and functional impairment. Patient-reported outcomes, including quality of life (QoL), are essential for understanding the overall impact of VS and its treatment. This study aimed to translate and culturally adapt the Vestibular Schwannoma Quality of Life (VSQOL) Index into German to expand its relevance to German-speaking populations. Methods: We used a qualitative approach including translation and cognitive interviews with 10 patients who underwent VS surgery. The translation process followed the TRAPD protocol to ensure linguistic and conceptual accuracy. Cognitive interviews assessed the comprehensibility and relevance of the translated questionnaire. Results: The translation showed remarkable consistency between translators, with minor discrepancies resolved by consensus. Cognitive interviews provided valuable insights that led to refinements in item wording. Participants emphasized the importance of an additional item on physician referrals, reflecting differences in health care systems between the United States and Germany. Conclusions: The German VSQOL provides a comprehensive tool for assessing QoL in patients with VS that integrates patient-centered dimensions. A Validation study is underway to establish its reliability and validity. [ABSTRACT FROM AUTHOR]

Background: Elderly patients with vestibular schwannoma (VS) are commonly observed. Object: Retrospective analysis of 25 patients aging ≥ 70 operated on in our neurosurgical department for unilateral VS. The purpose of our study is to propose an algorithm for the treatment of VS in elderly patients. Methods: American Society of Anesthesiology (ASA) Grade I-II patients and Grade III with life-threatening tumors were enrolled. Karnofsky Performance Status Scale (KPS) was used for evalutation of the quality of life. The House-Brackmann (HB) scale for facial nerve (FN) outcome was used. Tumor size was categorized according to Koos' classification. A retrosigmoid approach was used in all cases, except one in which a translabyrinthine approach was performed. Surgical removal graduation: total (GTR), near total (NTR > 95%), subtotal (STR > 90%). The clinical and radiological follow-up period was set first at six months and then at one year after surgery. FN results evaluation was performed at one year, categorized according to House-Brackmann grades I-VI. Results: Mean age: 74,4 years (70-83); 28% ASA I, 56% ASA II, 16% ASA III. Mean tumor size: 2,7 cm (1,5-4,2 cm). GTR/NTR: 68%, STR 32%. Mortality was zero. At last follow-up (one year after surgery) FN results were: HBI 81%, HBII 9.5%, HBIII 9.5%; HB IV 0%. Only 4 patients had preoperative HB IV, of whom one improved from HB IV to HB III. Transient complications occurred only in large VS. Re-growth of residue after STR was observed in 3 cases, treated with SRS in 2 cases and observed in 1. Conclusions: An algorithm of treatment of vestibular schwannoma in the elderly is proposed. In particular, in patients in general good conditions, age does not appear to be a major contraindication for microsurgery of VS. FN results at last follow-up are satisfactory and the complication rates are acceptable. [ABSTRACT FROM AUTHOR]

This study aimed to reveal the preferred initial treatment for Koos grade 3 vestibular schwannomas (VS). We performed a two-institutional retrospective study on 21 patients with Koos grade 3 VS undergoing resection at Yokohama Medical Center and 37 patients undergoing radiosurgery at Yokohama Rosai Hospital from 2010 to 2021. Tumor control, complications, and functional preservation were compared. The median pre-treatment volume and follow-up duration were 2845 mm3 and 57.0 months, respectively, in the resection group and 2127 mm3 and 81.7 months, respectively, in the radiosurgery group. In the resection group, 16 (76.2%) underwent gross total resection, and three patients (14.3%) experienced regrowth; however, no one required additional treatment. In the radiosurgery group, the tumor control rate was 86.5%, and three cases (8.1%) required surgical resection because of symptomatic brainstem compression. Kaplan–Meier analyses revealed that tumors with delayed continuous enlargement and large thin-walled cysts were significantly associated with poor prognostic factors (p = 0.0027, p < 0.001). The pre-radiosurgery growth rate was also associated with the volume increase (p = 0.013). Two cases (9.5%) required additional operation due to complications such as post-operative hematoma and cerebrospinal fluid leaks in the resection group, whereas temporary cranial neuropathies were observed in the radiosurgery group. Two patients (9.5%) had poor facial nerve function (House–Brackmann grading grade 3) in the resection group, while no one developed facial paresis in the radiosurgery group. Trigeminal neuropathy improved only in the resection group.Radiosurgery can be considered for the treatment of Koos grade 3 VS for functional preservation. However, resection may also be considered for patients with severe trigeminal neuropathy or a high risk of volume increments, such as large thin-walled cysts and rapid pre-treatment growth. [ABSTRACT FROM AUTHOR]

Aims: Esketamine may reduce acute postoperative pain in several settings. However, the effects of low‐dose esketamine on postoperative pain after vestibular schwannoma (VS) resection with propofol/remifentanil total intravenous anaesthesia (TIVA) are unclear. The aim of this study is to observe the effects of intraoperative low‐dose esketamine on postoperative pain after vestibular schwannoma resection. Methods: This single‐centre, randomized, placebo‐controlled, double‐blind trial included 90 adults undergoing VS resection via the retrosigmoid approach with TIVA. The patients were randomly allocated to two groups: esketamine or control (n = 45 in each group). Patients received low‐dose esketamine (0.2 mg/kg) or a similar volume of normal saline after dural closure. The primary outcome was the pain score during movement (gentle head movement) at 24 h postoperatively. Secondary outcomes included recovery time, bispectral index (BIS) values and haemodynamic profiles during the first 30 min after esketamine administration, and adverse effects. Results: Low‐dose esketamine did not reduce pain scores at rest (P >.05) or with movement (P >.05) within the first 24 h after surgery. Esketamine moderately increased BIS values for at least 30 min after administration (P <.0001) but did not affect heart rate (P =.992) or mean arterial blood pressure (P =.994). Esketamine prolonged extubation time (P =.042, 95% confidence interval: 0.08 to 4.42) and decreased the effect‐site concentration of remifentanil at extubation (P =.001, 95% confidence interval: −0.53 to −0.15) but did not affect the time to resumption of spatial orientation. Postoperative nausea and vomiting rates did not differ between groups, and no hallucinations or excessive sedation was observed. Conclusion: Intraoperative low‐dose esketamine did not significantly reduce acute pain after VS resection with propofol/remifentanil TIVA. However, BIS values increased for at least 30 min after esketamine administration. [ABSTRACT FROM AUTHOR]

Radiation treatment, particularly at a young age, creates theoretical risk for long-term adverse radiation effects, including the development of malignancy. The literature is sparse on radiation-induced vestibular schwannomas (VSs). A retrospective review was performed for cases of suspected radiation-induced VS at 2 high-volume centers. Only cases where radiation included coverage of the posterior fossa were included with those diagnosed within 3 years of radiation treatment being excluded. Patient and tumor characteristics were collected. A systematic literature review was also performed for any previously published series on radiation-induced VS. Eight cases of radiation-induced VS were identified with a median follow-up 125 months (range 7–131). The median age at incident radiation was 15 years (range 2–46). The median age at VS diagnosis was 57 years (range 26–83) with median interval from radiation to diagnosis of 51-years (range 15–66). The median tumor size was 6 mm (range 3–21). Two patients underwent surgical resection. Lesions were described as soft and highly vascular, with medium to high adherence to the facial nerve. Five articles with a total of 52 patients were identified, median age at VS diagnosis was 42-years (range 23–73) with a median interval from radiation to diagnosis of 19 years (range 15–23). The development of VS following radiation exposure appears rare and our understanding of the condition remains incomplete. Further studies are required to determine the best management of these patients and determine whether there is a causative relationship between radiation exposure and the development of VS. [ABSTRACT FROM AUTHOR]

Vestibular schwannomas (VSs) are benign tumors often monitored over time, with measurement techniques for assessing growth rates subject to significant interobserver variability. Automatic segmentation of these tumors could provide a more reliable and efficient for tracking their progression, especially given the irregular shape and growth patterns of VS. Various studies and segmentation techniques employing different Convolutional Neural Network architectures and models, such as U-Net and convolutional-attention transformer segmentation, were analyzed. Models were evaluated based on their performance across diverse datasets, and challenges, including domain shift and data sharing, were scrutinized. Automatic segmentation methods offer a promising alternative to conventional measurement techniques, offering potential benefits in precision and efficiency. However, these methods are not without challenges, notably the "domain shift" that occurs when models trained on specific datasets underperform when applied to different datasets. Techniques such as domain adaptation, domain generalization, and data diversity were discussed as potential solutions. Accurate measurement of VS growth is a complex process, with volumetric analysis currently appearing more reliable than linear measurements. Automatic segmentation, despite its challenges, offers a promising avenue for future investigation. Robust well-generalized models could potentially improve the efficiency of tracking tumor growth, thereby augmenting clinical decision-making. Further work needs to be done to develop more robust models, address the domain shift, and enable secure data sharing for wider applicability. [ABSTRACT FROM AUTHOR]

Cerebrospinal fluid (CSF) leak through petrosal air cells is a known complication after drilling the posterior wall of the internal acoustic canal (IAC) for resection of vestibular schwannoma (VS). Whereas mild pneumocephalus is common after retrosigmoid craniotomy, tension pneumocephalus has been rarely documented. To testify a case of fatal tension pneumocephalus after VS resection in a patient with ventriculo-peritoneal (VP) shunt and to propose possible recommendations to limit the risk of this dramatic complication. A case of fatal tension pneumocephalus after VS resection in presence of hidden CSF fistula is illustrated with pre- and post-operative images. In the uneventful situation of concomitant post-operative CSF fistula in presence of VP shunt, tension pneumocephalus may occur. The negative pressure created by the shunt system and the presence of osteo-dural defect allow the air to enter and, at the same time, prevent the outflow. After VS resection, tension pneumocephalus can occur as a consequence of CSF fistula from petrosal air cells in the presence of functioning VP shunt. Precautions as pre-operative increase to 'virtual-off' the pressure of the valve, subsequences CT scans after surgery and sealing of the petrous air cells are recommended to avoid such as fatal complication. [ABSTRACT FROM AUTHOR]

A recent trend of looking for health-related conditions on the Internet has been described, with up 70% of searchers stating that online sources have affected their medical decision-making. Patients with vestibular schwannomas (VS) use online sources, including videos, to seek information about treatment alternatives and outcomes and surgeons experience. Our study investigates the reliability and quality of VS-related online videos. In April 2020, a search was launched on YouTube for the key terms 'vestibular schwannoma,' 'acoustic neuroma,' 'eighth cranial nerve schwannoma,' and 'eighth cranial nerve neuroma.' Results were screened for possible inclusion. Three authors independently used the DISCERN instrument to evaluate the reliability and quality of the included videos. Factors possibly influencing popularity were investigated. The initial search yielded 6416 videos. 38 videos were included in the final analysis. The average DISCERN score was 2.76, indicating overall poor quality and reliability of information. Only 5% scored 4.0 or more (unbiased videos that offer evidence-supported information); 31% scored between 3.0 and 3.99, and 63% scored 2.99 or less. Videos describing symptoms or the patient's clinical presentation were slightly more popular than videos without these characteristics. Surgical videos (videos containing clips of surgical procedures) were significantly more popular than non-surgical videos (p =.024) despite being of similarly poor quality (DISCERN score 2.85 vs. 2.74, respectively). Available patient educational videos for VS are of mixed quality and reliability: the authors describe the strengths and pitfalls of existing YouTube videos. Considering that VS is a pathology with multiple available management modalities, and that patients' decision-making is affected by the information available on the Internet, it is of great importance that good-quality informative material be released by medical, academic, or educational institutions. [ABSTRACT FROM AUTHOR]

Objectives Distinguishing between sporadic and germline/mosaic NF2- related schwannomatosis is important to ensure that patients have appropriate long-term care. With this report, we describe a unique case of a patient with 4 ipsilateral schwannomas and identify a combination of sequencing modalities that can accurately diagnose mosaic NF2- related schwannomatosis. Methods We present a 32-year-old woman with a familial history of vestibular schwannoma in her father and right-sided schwannomas involving the apical and basal turns of cochlea, lateral semicircular canal, and internal auditory canal (IAC). Genetic analysis of blood and frozen tissue from 2 tumors (intralabyrinthine and IAC tumors) was performed using next-generation sequencing (NGS), multiplex ligation-dependent probe amplification (MLPA), and optical genome mapping (OGM). Results Germline testing for NF2, LZTR1, and SMARCB1 was negative. Tumor genetic testing revealed a shared NF2 pathogenic variant between the 2 tumors ("first hit") but distinct "second hit" NF2 variants, including mosaic loss of chromosome 22 in the IAC tumor seen only with OGM, consistent with mosaic NF2- related schwannomatosis. Conclusions Multimodality sequencing, including NGS, MLPA, and OGM, was required to ensure appropriate diagnosis of mosaic NF2- related schwannomatosis in this patient. A similar approach can be used for other patients with multiple ipsilateral tumors and suspected tumor predisposition. [ABSTRACT FROM AUTHOR]

Introduction This study highlights the relation between compound muscle action potential (CMAP) latency variations and the predictive value of facial nerve (FN) proximal-to-distal (P/D) amplitude ratio measured at the end of vestibular schwannoma resection. Methods Forty-eight patients underwent FN stimulation at the brainstem (proximal) and internal acoustic meatus (distal) using a current intensity of 2 mA. The proximal latency and the P/D amplitude ratio were assessed. House–Brackmann grades I & II indicated good FN function, and grades III to VI were considered fair/poor function. A P/D amplitude ratio > 0.6 was used as a cutoff to indicate a good FN function, while a ratio of ≤ 0.6 indicated a fair/poor FN function. Results The P/D amplitude ratio was measured for all patients, and the calculated sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) were 85.2, 85.7, 88.5, and 81.8%, respectively. The CMAPs from the mentalis muscle were then classified based on their proximal latency into group I (< 6 ms), group II (6–8 ms), and group III (> 8 ms). The SE, SP, PPV, and NPV became 90.5, 90.9, 95, and 83.3%, respectively, in group II. In group I, SE and NPV increased, whereas SP and PPV decreased. While in group III, SP and PPV increased, whereas SE and NPV decreased. Conclusion At a latency between 6 and 8 ms, the P/D amplitude ratio was predictive of outcomes with high SE and SP. When latency was < 6 ms or > 8 ms, the same predictive ability was not observed. Knowing the strengths and limitations is important for understanding the predictive value of the P/D amplitude ratio. [ABSTRACT FROM AUTHOR]

Objectives: To determine the natural history of hearing loss and tumor volume in patients with untreated neurofibromatosis type 2 (NF2)-related schwannomatosis. Moreover, we statistically examined the factors affecting hearing prognosis. Methods: This retrospective cohort study was conducted on 37 ears of 24 patients with NF2-related vestibular schwannomatosis followed up without treatment for more than 1 year. We obtained detailed chronological changes in the PTA and tumor volume in each case over time, and the rate of change per year was obtained. Multivariate analysis was also conducted to investigate factors associated with changes in hearing. Results: The average follow-up period was approximately 9 years, and hearing deteriorated at an average rate of approximately 4 dB/year. The rate of maintaining effective hearing decreased from 30 ears (81%) at the first visit to 19 ears (51%) at the final follow-up. The average rate of change in tumor growth for volume was approximately 686.0 mm3/year. This study revealed that most patients with NF2 experienced deterioration in hearing acuity and tumor growth during the natural course. A correlation was observed between an increase in tumor volume and hearing loss (r = 0.686; p < 0.001). Conclusions: Although the hearing preservation rate in NF2 cases is poor with the current treatment methods, many cases exist in which hearing acuity deteriorates, even during the natural course. Patients with an increased tumor volume during the follow-up period were more likely to experience hearing deterioration. Trial registration number 20140242 (date of registration: 27 October 2014). [ABSTRACT FROM AUTHOR]