Vestibular Schwannoma Research Articles

Predictors of trigeminal neuropathy in patients receiving Gamma Knife stereotactic radiosurgery for vestibular schwannoma.

The authors' objective was to validate dosimetric and clinical predictors of the development of trigeminal neuropathy (Tn) in patients treated with stereotactic radiosurgery (SRS) for a diagnosis of vestibular schwannoma (VS). In total, 301 patients were treated with SRS for VS at the authors' center between April 2013 and June 2020, with a median prescription dose of 12.5 Gy. Ninety-seven patients were excluded: 78 had pre-existing symptoms of Tn, and 19 had < 2 years of follow-up. At follow-up consultations, trigeminal nerve function was prospectively documented in an institutional database. The median follow-up was 4 years. Data from treatment plans were extracted for factors previously reported as predictors of Tn: volume of cranial nerve (CN) V that received at least 11 Gy, maximum dose to CN V, volume of the cisternal portion of CN V, maximum dose to the brainstem, volume of the brainstem that received at least 12 Gy, and tumor volume. Tumor compression of CN V at baseline was also evaluated. Univariate and multivariate analyses of results were performed to identify significant factors. In total, 23 (11.3%) patients developed symptoms of Tn after SRS; these symptoms were transitory in 7 (30%) cases. Of the 16 patients with permanent Tn, 13 had objective paresthesia (9 had grade II and 4 grade III) and 5 had pain (2 grade II and 3 grade III); included in this are 2 patients who had both paresthesia and pain. In addition, 44% developed symptoms by 1 year after SRS and 100% by 3 years after SRS. On univariate analysis of patients with permanent symptoms, maximum dose to CN V (p = 0.016) was a significant factor. This was not maintained on multivariate analysis when the volume of CN V that received ≥ 11 Gy became the only significant factor (p = 0.029). The only significant factor in the risk of development of Tn after SRS for VS was the volume of CN V that received ≥ 11 Gy. This should be routinely incorporated into dosimetric planning constraints and patients should be counseled about the risk of adverse effects if it cannot be met. For those with growing VS and a gap to the trigeminal nerve, it may be prudent to provide earlier treatment with SRS to enable application of this dosimetric constraint and reduced risk of Tn.

Quantitative Assessment of Collagen Architecture to Determine Role of Tumor Stroma During Vestibular Schwannoma Progression.

The primary objective was to characterize the abundance and architecture of collagen in the extracellular matrix in vestibular schwannoma (VS). The secondary objective was to investigate the association between collagen architecture and tumor size. Retrospective cohort study. Academic referral center. Tumor samples were obtained from patients with sporadic VS undergoing microsurgical resection. Histological analyses were performed including picrosirius red (PSR) staining under polarized light. Collagen architecture was quantified using an automated fiber detection software. Second Harmonic Generation (SHG) microscopy and immunofluorescence (IF) were utilized to characterize collagen architecture. Eleven tumor specimens were included (mean tumor diameter = 2.80 cm, range 1.5-4.0 cm), and were divided into large (mean diameter = 3.5 ± 0.4 cm) and small (mean tumor diameter = 2.0 ± 0.4 cm) cohorts based on size. The large VS cohort showed significantly higher collagen density (27.65% vs 12.73%, P = .0043), with more thick fibers (mature Type I, 24.54% vs 12.97%, P = .0022) and thin fibers (immature Type I or mature Type III, 23.55% vs 12.27%, P = .026). Tumor volume correlated with greater degree of collagen fiber disorganization (P = .0413, r2 = 0.298). Specifically, collagen type I intensity was significantly higher in large VS compared to small tumors (P < .001) and peripheral nerve (P = .028). Larger VS exhibit increased collagen abundance in the tumor stroma, and a more disorganized collagen architecture compared to smaller VS and normal peripheral nerve tissue. This finding indicates that collagen organization may play a significant role in extracellular matrix remodeling and the progression of VS.

Associations of Microvascular Risk Factors with Sporadic Vestibular Schwannoma Outcomes Following Stereotactic Radiosurgery.

Stereotactic radiosurgery (SRS) is increasingly used for small-to-medium-sized sporadic vestibular schwannoma (VS) and is associated with good tumor control and low-risk of adverse radiation-associated events. The exact mechanism of VS tumor control is unknown but may relate to microvascular hyalinization and resultant tumoral ischemia. This study examined associations of microvascular risk factors with outcomes following SRS. Historical cohort of patients who underwent SRS for sporadic VS from 2000 to 2022. Tertiary academic center. Associations of microvascular risk factors with tumor control and complications were evaluated using Cox proportional hazards regression. In total 749 patients were studied, 31% with a history of smoking, 38% obesity, 19% hypertension, 8% diabetes, 3% peripheral vascular disease, and 2% history of coronary bypass. Regarding tumor control, no factor was associated with salvage treatment following SRS (n = 42). Hypertension (hazard ratio [HR] 2.81; P = .02) and coronary bypass (HR 6.91; P = .002) were significantly associated with developing facial nerve paresis (n = 22). No significant associations with new facial spasms (n = 53) were identified. Lastly, 191 of 294 patients with serviceable hearing at SRS progressed to nonserviceable hearing at a median 2.0 years (interquartile range: 1.0-5.0). After multivariable adjustment for age and ipsilateral hearing status, the HR for the association of smoking history with time to nonserviceable hearing was 1.46 (95% confidence interval 1.04-2.04; P = .03). We demonstrate that hypertension and history of coronary bypass may be associated with development of facial nerve weakness, while smoking may be associated with accelerated hearing loss in patients undergoing SRS for sporadic VS. These data may help guide patient counseling and inform decision-making regarding treatment.

Vestibular Schwannoma Koos Grade II International Study of Active Surveillance Versus Stereotactic Radiosurgery: The VISAS-K2 Study.

This study assessed the efficacy and safety of stereotactic radiosurgery (SRS) in comparison with watchful waiting for managing Koos grade II vestibular schwannomas (VS). A retrospective, multicentric analysis was conducted, focusing on patients with Koos grade II VS who either received SRS (SRS group) or were observed (observation group). To ensure comparability between groups, propensity score matching was used, including factors such as demographic characteristics, tumor dimensions, and hearing assessments. The primary end points examined were tumor control, maintenance of serviceable hearing, and neurological outcomes. A total of 92 patients were equally matched across both cohorts, with a median follow-up of 37 months for the SRS group and 27.5 months for those observed. The SRS cohort exhibited superior tumor control over observation across 3, 5, and 8 years, achieving a 100% control rate vs 47.9%, 40.1%, and 34.3% for the observation group at these time intervals, respectively (P < .001). Serviceable hearing preservation rates were comparable between the 2 groups throughout 3, 5, and 7 years (72.9% for SRS vs 65.4% for observation at 3 years; P = .86). Moreover, SRS management correlated with a lower incidence of vestibular symptoms (odds ratio = 0.11, P = .002), with no significant disparity in the deterioration of cranial nerve (CN) V or CN VII functions. Notably, the likelihood of experiencing any CN impairment was significantly diminished in the SRS cohort (odds ratio = 0.47, P = .04). For patients with Koos grade II VS, SRS offers superior tumor control rate and a lower risk of CN dysfunction without sacrificing hearing preservation.

Vestibular Schwannoma Koos Grade I International Study of Active Surveillance Versus Stereotactic Radiosurgery: The VISAS-K1 Study.

This investigation evaluates the safety and efficacy of stereotactic radiosurgery (SRS) vs observation for Koos grade I vestibular schwannomas (VS). In a multicenter study, we retrospectively analyzed data of patients with Koos grade I VS who underwent SRS (SRS group) or were observed (observation group). Propensity score matching was used to equilibrate demographics, tumor size, and audiometric data across groups. The outcome analyzed included tumor control, preservation of serviceable hearing, and neurological function. The study matched 142 patients, providing a median follow-up period of 36 months. SRS significantly enhanced tumor control compared with observation, with a 100% control rate at both 5- and 8-year marks in the SRS group vs 48.6% and 29.5% in the observation group at the same time intervals, respectively (P < .001). Preservation of serviceable hearing outcomes between groups showed no significant difference at 5 and 8 years, ensuring a comparable quality of auditory function (SRS 70.1% vs observation 53.4% at 5 years; P = .33). Furthermore, SRS was associated with a reduced likelihood of tinnitus (odds ratio [OR] = 0.46, P = .04), vestibular dysfunction (OR = 0.17, P = .002), and overall cranial nerve dysfunction (OR = 0.49, P = .03) at last follow-up. SRS management of patients with Koos grade I VS was associated with superior tumor control and reduced odds for cranial nerve dysfunction, while not compromising hearing preservation compared with observation. These findings support the safety and efficacy of SRS as a primary care approach for this patient population.

British Skull Base Society Consensus on Vestibular Schwannoma Surveillance

Abstract Objective Surveillance plays a crucial role in managing patients with vestibular schwannomas (VSs). Consensus is lacking on the optimal duration, frequency, and modality of imaging. Standardizing this approach would ensure safe and effective care, reduce patient distress, and promote consistency in management decisions among clinicians. Methods In July 2022, a multi-disciplinary Delphi consensus was conducted at the British Skull Base Society Meeting. Expert United Kingdom-based skull-base surgeons and neuroradiologists were presented semi-systematic literature reviews summarizing current evidence on VS management. Anonymized opinions were collated and discussed to reach a majority vote, which was deemed the final consensus opinion. Results Recommendations for VS managed by surveillance are: (1) surveillance frequency should decrease over time; (2) surveillance may be discontinued when the remaining lifetime risk of VS growth is &lt;0.5% (∼8.5 years); (3) factors such as age, VS size, VS location, and cystic components should be considered. Surveillance after surgery or radiotherapy has limited evidence but recommendations are: (4) surveillance should be adjusted based on residual tumor size or nodular enhancement. Imaging modality and sequences are recommended to be (5) high-resolution magnetic resonance imaging with T1, T2, FIESTA/CISS multiplanar sequences, contrast is not required in untreated cases, and linear reporting of measurements is pragmatically sufficient. Conclusion This consensus and literature review provides an evidence and expert opinion–based guide to help clinicians with the surveillance of patients with VS. Further research should focus on better understanding the dynamic nature of growth risks and the growth characteristics of postintervention VS to enable personalized growth risk stratification.

Analysis of Adherence to AAO-HNSF Clinical Practice Guidelines for Sudden Hearing Loss.

To assess adherence to the 2019 American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNSF) guidelines for the diagnosis and management of sudden hearing loss (SHL) and sudden sensorineural hearing loss (SSNHL). Retrospective cohort. TriNetX, a de-identified healthcare database. Evaluation focused on the percentage of patients undergoing proper guideline-adherent workup and treatment for SHL. Key measures include audiogram testing within 2 weeks for distinguishing SSNHL from CHL. For SSNHL patients, MRI or auditory brainstem response (ABR) testing should be obtained, and steroids and/or hyperbaric oxygen may be offered within 2 weeks. There were 24,203 SHL patients, 59.1% (n = 14,309) of whom underwent recommended audiogram testing, with 35.8% (n = 8,674) completing it within 2 weeks. Overall, 3,107 were diagnosed with unilateral SSNHL, 104 with unilateral conductive hearing loss (CHL), 121 with mixed hearing loss, and 10,977 were lost to follow-up. Among 3,107 SSNHL cases, just 25.5% (n = 791) obtained MRI/ABR within 1 month, and vestibular schwannoma was diagnosed in 3.5% (n = 28). Additionally, steroids were prescribed to 54.5% (n = 1,692), and <0.3% (n ≤ 10) received hyperbaric oxygen. In accordance with strong recommendations against or insufficient evidence to support the following diagnostics and treatments, 2.0% (n = 63) underwent a CT scan, less than 0.3% (n ≤ 10) were prescribed vasodilators or thrombolytics, and 3.5% (n = 108) were on antivirals. There is a significant opportunity for improvement in evaluating patients with SHL, specifically SSNHL. Proper adherence to guidelines may improve screening, detection, and management of neurotologic pathologies, including vestibular schwannoma.

Endosaccular Coil Embolization of Ruptured Anterior Inferior Cerebellar Artery Pseudoaneurysm After Gamma Knife Surgery for Vestibular Schwannoma: A Case Report and Literature Review

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.

The importance of simultaneous oculoplastic surgery in quality of life related to vision in surgical resection of large vestibular schwannomas.

Facial nerve palsy is one of the most important complications of vestibular schwannoma resection. When VII cranial nerve is damaged, ocular complications might appear, impacting patient´s quality of life. Therefore, standardized eye care must be a priority. This involves three key treatments: topical treatment, rehabilitation and oculoplastic surgery. The aim of this work is to review the results of oculoplastic surgery performed simultaneously with vestibular schwannoma resection in terms of vision-related quality of life, compared to deferred surgery. The study involved 177 patients who underwent vestibular schwannoma resection between 2015 and 2022. The incidence of facial palsy was registered. Of those patients who had the palsy, we selected 35 who also had oculoplastic surgery. 5 of them declined participating in the study. The final sample (n = 30) was divided in two groups depending on the timing of oculoplastic surgery: simultaneously- first group (n = 15) and deferred-second group (n = 15). The vision-related quality of life was measured using the NEI VFQ-25 test. 26.56% patients developed an immediate postoperative facial dysfunction, decreasing to 18.08% after one year of follow-up. Timing of oculoplastic surgery was associated with better results in quality of life; the first group of patients had a better quality of life (70.27/100) compared to the second group (53.73/100; p = 0.006). Moreover, worse results in quality of life were also associated with long-term postoperative facial palsy (p = 0.042). Current criteria for selecting patients were reliable, proving adequacy as we found worse long-term facial functions in patients who underwent simultaneous surgery (p = 0.01). Our current criteria for selecting candidates for simultaneous oculoplastic surgery are effective. When long-term facial nerve dysfunction is expected during vestibular schwannoma resection, oculoplastic surgery should be performed simultaneously to preserve the q vision-related quality of life. Long-term severe facial palsy is associated with poor vision-related quality of life.

CSS-Net: A Collaborative Framework for Synthesis and Segmentation of Missing Contrast-enhanced Image with Error-Prediction Consistency

Abstract Automated tumor segmentation plays a critical role in facilitating the diagnosis and assessment of disease progression. Within the realm of tumor segmentation, Contrast-Enhanced (CE) scans are an effective imaging tool that allows for more intuitive observation of tumor characteristics and generally provide better segmentation results compared with Non-Contrast-Enhanced (NCE) scans alone. However, CE images are not available in most cases due to the time-consuming and costly need for contrast and repeat scans. To solve this issue, this paper proposes a Collaborative framework for the Synthesis and Segmentation of missing CE images in medical imaging with error-prediction consistency (CSS-Net). CSS-Net simultaneously addresses synthesis and segmentation tasks, generating both the synthesized CE images and coarse segmentation results. Subsequently, a multi-layer adaptive feature fusion strategy is utilized to effectively leverage the correlation between these tasks, resulting in refined segmentation results. Additionally, the proposed method incorporates a multi-layer feature fusion block, which adaptively selects features pertinent to segmentation. Furthermore, error-prediction consistency is also introduced between coarse and refined segmentation for regularization, leading to high-performance segmentation results. What’s more, we constructed a multimodal esophageal tumor segmentation dataset with 902 patients and validated it on this dataset and two publicly available multimodal brain tumor datasets. The results indicate that our method achieved Dice scores of 89.04% in esophageal tumor segmentation, 77.01% in whole glioma segmentation, and 91.14% in Vestibular Schwannoma segmentation. This performance surpasses that of segmentation using only available modalities and other image synthesis-based segmentation methods, demonstrating the superior robustness of CSS-Net.

Use of Ultra-Short Echo Time MRI to Improve Temporal Bone Imaging.

The short T2 nature of cortical bone causes it to appear similar to air on MR, forcing clinicians to rely on computed tomography imaging, with its attendant ionizing radiation exposure, to define temporal bone structures. Through the use of novel MR sequences with ultra-short echo times (UTE), short T2 structures are now able to be visualized, allowing for improved understanding of anatomical relationships. Eight patients (50% female) undergoing MR imaging of the skull base for diagnostic purposes (62.5% for vestibular schwannoma surveillance) at a tertiary care center were enrolled to evaluate the safety and efficacy of UTE imaging. CT scans were completed in 37.5% of the patients as part of their workup and used for comparison purposes. The repetition time, short echo time, and long echo time for the UTE sequence were 11, 0.032, and 2.2 msec, respectively. The protocol added 6 min to the total scanning time, and all patients tolerated the sequence without issue. The ossicles, mastoid air cells, antrum, and epitympanum were able to be seen and had a high Dice similarity coefficient when compared to CT (>0.5). UTE allowed for clear delineation of all segments of the facial nerve with a signal-to-noise ratio of 35 (although the BRAVO sequences had a superior ratio of 140). Vestibular schwannomas were able to be distinguished from normal brain parenchyma. UTE is safe and effective for visualizing anatomic structures not normally seen on traditional MRI, potentially allowing for improved surgical planning in patients. 3 Laryngoscope, 134:4691-4696, 2024.

Exploring the Role of Inflammatory Genes and Immune Infiltration in Vestibular Schwannomas Pathogenesis

Exploring the Role of Inflammatory Genes and Immune Infiltration in Vestibular Schwannomas Pathogenesis

Revised Classification of Inner Ear Schwannomas.

Over the past two decades, there has been increasing interest in the diagnosis and management of schwannomas of the inner ear including hearing rehabilitation with cochlear implants. However, tumor nomenclature and classification within the literature have been variable and oftentimes cumbersome. The term "intralabyrinthine schwannoma" is in common use when describing these tumors but is a potential source of confusion given that people often use the term "labyrinth" or "labyrinthine" to refer to the vestibular component of the inner ear only (i.e., labyrinthectomy or the translabyrinthine approach).During the Ninth Quadrennial Conference on Vestibular Schwannoma and Other Cerebellopontine Angle Lesions in Bergen, Norway, in May 2023, a multidisciplinary group of conference participants met and discussed issues pertaining to current terminology and classifications to enhance clarity and to reflect recent advances in tumor management and hearing rehabilitation.Although a variety of terms have been previously used to describe inner ear schwannomas, consensus was achieved on the term "inner ear schwannoma (IES)" to describe eighth nerve schwannomas of the cochlea, vestibule, or semicircular canals. Subgroups under this term comprise intravestibular, intracochlear, or intravestibulocochlear inner ear schwannomas (low complexity tumors), inner ear schwannomas with transfundal extension into the internal auditory canal but without modiolar involvement (intermediate complexity tumors), and inner ear schwannomas with transfundal extension with modiolar involvement (high complexity tumors).The details of the recommendations for an updated and simplified tumor nomenclature centered around tumor control and hearing rehabilitation with cochlear implantation are presented.

Functional Outcomes and Self-Reported Quality of Life in Patients with Facial Nerve Impairment Following Vestibular Schwannoma Surgery

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 &lt; 0.001), accumulation of food in the oral vestibule (p &lt; 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.

Concurrent fibrous dysplasia is associated with a high incidence of cystic formation in vestibular schwannomas.

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). 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. 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. 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.

Effectiveness of CI as an alternative to ABI for hearing loss in patients with vestibular schwannomas: A multicenter study in Japan

ObjectiveNF2-related schwannomatosis (NF2) is characterized by bilateral vestibular schwannomas (VS), often causing severe damage to the bilateral auditory function. Auditory brainstem implantation (ABI) provides hearing-impaired patients with an opportunity to reacquire auditory sensation through electrical stimulation of auditory neurons in the cochlear nucleus. However, ABI is not covered by public health insurance in Japan, leading to a large difference in financial burden compared to cochlear implantation (CI). The aim of the present study was to demonstrate the effectiveness of CI as an alternative to ABI for hearing reacquisition in patients with profound hearing loss caused by VS. MethodsTo investigate the current situation of ABI and CI for hearing reconstruction in VS patients, we conducted a questionnaire survey of 102 facilities in Japan. Based on the responses to the questionnaire, a multicenter research group consisting of otolaryngologists and neurosurgeons was established. We collected detailed data on patients with VS who underwent ABI (n = 7, all NF2) and CI (n = 14 [nine NF2, and five non-NF2]). ResultsSome sense of hearing was obtained in all patients but one with CI indicating the efficacy of CI and ABI for profound hearing loss caused by VS. The mean hearing levels were 45.4 dB HL in the ABI patients and 32.7 dB HL in the CI patients, indicating that CI was effective as an alternative to ABI. ConclusionThe results of the present study suggest the effectiveness of CI as an alternative to ABI for hearing reacquisition in patients with profound hearing loss caused by VS. Level of evidence4.

Stereotactic Radiosurgery in Primary Treatment of Sporadic Small to Medium (

To analyze the current literature regarding use of SRS as primary treatment of VS to further evaluate efficacy and treatment-related neurologic deficits. Online databases were queried to identify relevant publications from January 2001-December 2020. Full text, English articles for sporadic VS treated primarily with radiosurgery and documented hearing preservation data were reviewed. Papers that had a minimum follow-up period of less than 36 months, did not utilize radiosurgery for primary treatment, or included patients with Neurofibromatosis II were excluded. A total of 33 studies involving 4286 patients with an average follow-up of 62.5 months were included in the final analysis. All 33 studies included eligible hearing data; overall preservation of serviceable hearing was found to be 58.27%. 27 studies with 3822 eligible patients were analyzed for tumor control rates; overall, tumor control was reported in 92.98% of cases. 27 studies were analyzed for post-treatment facial nerve dysfunction which was reported in 1.53% of cases. SRS is a safe and effective primary treatment modality for sporadic vestibular schwannoma as evidenced by the present analysis. Radiosurgery is effective with regard to tumor control and hearing preservation while offering a low rate of post-treatment facial nerve dysfunction.

Erosion of the temporal bone by vestibular schwannoma: morphometrics and predictive modeling.

To perform a comprehensive morphometric analysis of vestibular schwannomas (VS) using multimodal imaging, focusing on the relationship between tumor characteristics and internal acoustic canal (IAC) changes. We analyzed a cohort of patients undergoing radiosurgery for VS, utilizing high-definition MRI and bone CT for detailed anatomical assessment. Image co-registration and fusion techniques were employed to examine VS and IAC dimensions. Advanced statistical methods, including logistic regression, were applied to identify patterns of IAC dilation and establish predictive indicators for these morphological changes. The study included 659 patients (51.1% female, mean age 56.37years) with evenly distributed tumor lateralization. Koos grades were I (22.9%), II (29.9%), III (38.2%), IVa (8.9%), and IVb (0.3%). Most tumors (90.9%) extended both inside and outside the IAC. Ipsilateral IAC (IIAC) dimensions were significantly larger than contralateral, with IIAC volume 49% greater (p < .0001). Higher Koos grades correlated with increased intra-canalicular lesion volume (icLV), which was strongly associated with IIAC size. Logistic regression identified icLV as the strongest predictor of IIAC dilation (AUC = 0.7674, threshold = 137.52 mm3). The icLV appears central to the pathophysiological development of VS and its impact on IAC anatomy. While limited by a selective patient base and static imaging data, these findings enhance the understanding of VS-IAC interactions, offering insights for improved clinical management and further research.

Translabyrinthine versus Retrosigmoid Approach for Vestibular Schwannoma: A Systematic Review and An Updated Meta-Analysis.

Several approaches can be used in the surgical treatment of vestibular schwannoma (VS), and the best approach remains uncertain in the literature. This systematic review and meta-analysis aim to compare the translabyrinthine approach (TLA) with the retrosigmoid approach (RSA) for VS in terms of postoperative complications. PubMed, Web of Science, Embase, and Cochrane. The primary outcome was cerebrospinal fluid (CSF) leak; secondary outcomes were facial nerve dysfunction (FND), length of stay (LOS), and meningitis. Statistical analysis was performed using RStudio 2024.04.1 + 748. Heterogeneity was assessed with I² statistics. We performed sensitivity analysis with subgroup analysis and meta-regression. Risk of bias was assessed using ROBINS-I. Out of 1140 potential articles, 21 met the inclusion criteria. Among the 4572 patients, 2687 and 1885 patients in the TLA and RSA groups, respectively. No significant differences were found in CSF leak (odds ratio [OR] 1.03; 95% confidence interval [CI] 0.81,1.32; P = .794) or meningitis (OR 1.05; 95% CI 0.45, 2.43; P = .73). Meta-regression showed no association with CSF leak and the number of cases per center or publication year. The TLA is associated with a shorter LOS (MD -1.20; 95% CI -1.39, -1.01; P < .01) and a higher chance of having and HB 4 or lower compared to patients who underwent RSA (OR 0.30; 95% CI 0.10, 0.89; P = .03). There was no difference in the odds of CSF leak or meningitis between the groups. In addition, the TLA has a shorter LOS and a higher chance of a better facial nerve outcome compared to the RSA.

Incidental Findings on MRIs for Asymmetric Sensorineural Hearing Loss: A Clinical and Economic Analysis.

The gold-standard assessment of asymmetric sensorineural hearing loss (ASNHL) is contrast-enhanced MRI. Although rates of identifying a vestibular schwannoma are low (<5%), it is generally accepted as cost-effective. Yet, the impact of incidentalomas is rarely considered. This study aims to characterize the incidence of incidentalomas in the workup of ASNHL and quantify the associated socioeconomic burden. Retrospective cohort study. Single academic institution in a midsized city in the United States. Radiology records were queried for MRI's ordered for ASNHL between January 2012 and November 2022. Results were characterized as "group 1: normal," "group 2: abnormal read/normal variant," "group 3: abnormal-likely cause of ASNHL," or "group 4: abnormal-follow-up needed." Subsequent costs of workup for group 4 were estimated using Medicare Physician Fee Schedule for Medicare costs, US Congressional Budgeting Office data for private insurer costs, and USC-Brookings Schaeffer Initiative for Health Policy estimates for uninsured individuals. Six hundred patients met the inclusion criteria. Eighteen (3.0%) were categorized in group 3, whereas 40 (6.7%) were categorized in group 4. Of these patients, 7.5% (n = 3) had interventions to manage their incidental findings. Estimated per patient cost for further workup of incidental findings amounted to approximately $744, $1,534, and $2,260 for Medicare, private insurance, and uninsured costs, respectively. Incidentalomas occur over twice as often as retrocochlear pathologies responsible for ASNHL. Although the number of patients requiring treatment for incidentaloma is low, the economic impact is not insubstantial and should be considered for both individual patients and health system payers.