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World Neurosurgery Feb 2017Synchronous tumors of the cerebellopontine angle (CPA) are very rare and inconsistently described. We present 2 cases of contiguous vestibular schwannoma (VS) and... (Review)
Review
BACKGROUND
Synchronous tumors of the cerebellopontine angle (CPA) are very rare and inconsistently described. We present 2 cases of contiguous vestibular schwannoma (VS) and meningioma and a systematic literature review of all multiple CPA tumors.
METHODS
Retrospective chart review and systematic literature review were performed.
RESULTS
A 64-year-old woman and a 42-year-old man presented with symptoms referable to the CPA. Magnetic resonance imaging in both patients revealed 2 separate contiguous tumors. Retrosigmoid craniotomy and tumor removal in each case confirmed VS and meningioma. Systematic literature review identified 42 previous English-language publications describing 46 patients with multiple CPA tumors. Based on Frassanito criteria, there were 4 concomitant tumors (8%), 16 contiguous tumors (33%), 3 collision tumors (6%), 13 mixed tumors (27%), and 11 tumor-to-tumor metastases (23%). Extent of resection was gross total in 16 cases and subtotal in 16 cases (50% each). Unfavorable House-Brackmann grade III-VI function was documented in 27% overall and in 33% of patients with VS and meningioma, a marked increase from the observed range in isolated VS.
CONCLUSIONS
Multiple CPA tumors are rare, heterogeneous lesions with a marked predisposition toward poor facial nerve outcomes, potentially attributable to a paracrine mechanism that simultaneously drives multiple tumor growth and increases invasiveness or adhesiveness at the facial nerve-tumor interface. Preceding nomenclature has been confounding and inconsistent; we recommend classifying all multiple CPA tumors as "synchronous tumors," with "schwannoma with meningothelial hyperplasia" or "tumor-to-tumor metastases" reserved for rare, specific circumstances.
Topics: Adult; Cerebellar Neoplasms; Cerebellopontine Angle; Craniotomy; Female; Humans; Magnetic Resonance Imaging; Male; Meningeal Neoplasms; Meningioma; Middle Aged; Neoplasms, Multiple Primary; Neuroma, Acoustic; Retrospective Studies
PubMed: 27836701
DOI: 10.1016/j.wneu.2016.11.002 -
European Archives of... Nov 2022Most ELST data in the literature are case studies or limited to small cohorts (< 16 patients). We evaluated the main clinical signs observed at endolymphatic sac tumor... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Most ELST data in the literature are case studies or limited to small cohorts (< 16 patients). We evaluated the main clinical signs observed at endolymphatic sac tumor (ELST) diagnosis in patients with or without Von Hippel-Lindau disease.
METHODS
We conducted a comprehensive literature search in PubMed, Scopus, and Web of Science. We included studies with at least 1 patient, of any age, affected by sporadic or VHL-related ELSTs reporting levels of hearing loss and facial nerve function and a comprehensive description of presenting symptoms at ELST diagnosis. We combined data for proportional meta-analysis. p values of 0.05 were considered statistically significant. Methodological quality was evaluated. Analyses were performed with MedCalc 14.8.1 software.
RESULTS
A total of 26 studies, including 113 patients and 118 cases of ELSTs were included. Pooled proportion rates (95% CI) of overall hearing loss was 88.7%, (82.4-93.4), severe hearing loss was 21.6% (12.8-32.1) profound hearing loss was 39.8% (28.7-51.5), vertigo/imbalance was 42.0% (33.8-50.5), tinnitus was 61.8% (53.4-69.8) and facial nerve palsy was 30.6% (23.2-38.9). Generally, symptoms were homogeneous or moderately heterogeneous among included studies.
CONCLUSION
This is the first systematic review of clinical presentations at ELST diagnosis. The most serious clinical events include profound hearing loss and facial impairment. Fluctuating hearing loss, tinnitus and vertigo are frequently reported and may confound correct and prompt ELST diagnosis.
Topics: Adenoma; Bone Neoplasms; Ear Neoplasms; Endolymphatic Sac; Hearing Loss; Humans; Labyrinth Diseases; Tinnitus; Vertigo; von Hippel-Lindau Disease
PubMed: 35704074
DOI: 10.1007/s00405-022-07469-6 -
Otology & Neurotology : Official... Mar 2021To perform a systematic review and meta-analysis summarizing the current evidence on the management of intracanalicular vestibular schwannoma. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To perform a systematic review and meta-analysis summarizing the current evidence on the management of intracanalicular vestibular schwannoma.
DATA SOURCES
Embase (1947-), Medline (1946-), Cochrane library (1947-), Scopus (2010-), and CINAHL (1961-) were searched from 1969 to October 5, 2019 (50 years).
STUDY SELECTION
A search strategy was performed to identify patients with vestibular schwannoma confined to the internal auditory canal without extension to the cerebellopontine angle. Studies with patients aged less than 18, Neurofibromatosis type 2, revision cases, and non-English language were excluded.
DATA EXTRACTION
A standardized collection sheet was used for the extracted data and a quality assessment was performed using the Newcastle-Ottawa Scale with the comparability criterion omitted.
DATA SYNTHESIS
Seventy-one studies were included with 24 on observation, 14 on radiotherapy, and 34 on surgery. The primary outcome was serviceable hearing preservation. Secondary outcomes were preservation of facial nerve function, growth, involution, and dizziness. Sub-analysis on the type of surgery and type of radiotherapy were performed. Excel 2016 with MIX 2.0 Pro add-on package was used to analyze the data and create forest plots. Data were presented in proportion with a 95% confidence interval.
CONCLUSIONS
Serviceable hearing was observed in 31% of patients after observation, 56% after radiotherapy, and 51% after surgical treatment with mean follow-up time of 4.04 years, 4.92 years, and 2.23 years, respectively. Facial nerve function was found to be best preserved in both observation and radiotherapy groups. Vestibular schwannoma growth occurred in 33% of patients under observation. Involution occurred in 2% of patients under observation and in 38% after radiotherapy.
Topics: Aged; Hearing; Hearing Loss; Hearing Tests; Humans; Neuroma, Acoustic; Radiosurgery; Treatment Outcome
PubMed: 33555742
DOI: 10.1097/MAO.0000000000002979 -
Neurosurgery Feb 2018Does intraoperative facial nerve monitoring during vestibular schwannoma surgery lead to better long-term facial nerve function?
QUESTION 1
Does intraoperative facial nerve monitoring during vestibular schwannoma surgery lead to better long-term facial nerve function?
TARGET POPULATION
This recommendation applies to adult patients undergoing vestibular schwannoma surgery regardless of tumor characteristics.
RECOMMENDATION
Level 3: It is recommended that intraoperative facial nerve monitoring be routinely utilized during vestibular schwannoma surgery to improve long-term facial nerve function.
QUESTION 2
Can intraoperative facial nerve monitoring be used to accurately predict favorable long-term facial nerve function after vestibular schwannoma surgery?
TARGET POPULATION
This recommendation applies to adult patients undergoing vestibular schwannoma surgery.
RECOMMENDATION
Level 3: Intraoperative facial nerve can be used to accurately predict favorable long-term facial nerve function after vestibular schwannoma surgery. Specifically, the presence of favorable testing reliably portends a good long-term facial nerve outcome. However, the absence of favorable testing in the setting of an anatomically intact facial nerve does not reliably predict poor long-term function and therefore cannot be used to direct decision-making regarding the need for early reinnervation procedures.
QUESTION 3
Does an anatomically intact facial nerve with poor electromyogram (EMG) electrical responses during intraoperative testing reliably predict poor long-term facial nerve function?
TARGET POPULATION
This recommendation applies to adult patients undergoing vestibular schwannoma surgery.
RECOMMENDATION
Level 3: Poor intraoperative EMG electrical response of the facial nerve should not be used as a reliable predictor of poor long-term facial nerve function.
QUESTION 4
Should intraoperative eighth cranial nerve monitoring be used during vestibular schwannoma surgery?
TARGET POPULATION
This recommendation applies to adult patients undergoing vestibular schwannoma surgery with measurable preoperative hearing levels and tumors smaller than 1.5 cm.
RECOMMENDATION
Level 3: Intraoperative eighth cranial nerve monitoring should be used during vestibular schwannoma surgery when hearing preservation is attempted.
QUESTION 5
Is direct monitoring of the eighth cranial nerve superior to the use of far-field auditory brain stem responses?
TARGET POPULATION
This recommendation applies to adult patients undergoing vestibular schwannoma surgery with measurable preoperative hearing levels and tumors smaller than 1.5 cm.
RECOMMENDATION
Level 3: There is insufficient evidence to make a definitive recommendation. The full guideline can be found at: https://www.cns.org/guidelines/guidelines-manage-ment-patients-vestibular-schwannoma/chapter_4.
Topics: Adult; Facial Nerve; Facial Nerve Injuries; Female; Humans; Intraoperative Neurophysiological Monitoring; Middle Aged; Neuroma, Acoustic; Neurosurgical Procedures; Vestibulocochlear Nerve; Vestibulocochlear Nerve Injuries
PubMed: 29309641
DOI: 10.1093/neuros/nyx513 -
Neuro-oncology Practice Aug 2021Large vestibular schwannomas (VS) pose a treatment challenge for both microsurgery (MS) and stereotactic radiosurgery (SRS). Technical developments have allowed for... (Review)
Review
BACKGROUND
Large vestibular schwannomas (VS) pose a treatment challenge for both microsurgery (MS) and stereotactic radiosurgery (SRS). Technical developments have allowed for safer irradiation of large tumors. It remains unclear if SRS can achieve appropriate tumor control and acceptable cranial nerve toxicities. In this study, we assess outcomes of irradiation for large VS.
METHODS
PubMed MEDLINE, EMBASE, Web of Science, and Cochrane were searched for all the studies assessing SRS outcome in large VS. Primary endpoints included clinical and radiographic tumor control, need for salvage surgery, serviceable hearing, cranial nerve V and VII impairment, presence of hydrocephalus requiring shunting, and presence of vertigo/dizziness.
RESULTS
Twenty-two studies were identified that met selection criteria for analysis from an initial pool of 1272 reports. They were evaluated according to treatment protocol: 1) single-dose SRS (13 studies, 483 patients), 2) combination of MS and SRS (7 studies, 182 patients), and 3) fractionated SRS (3 studies, 82 patients). Tumor control was achieved in 89%, 94%, and 91% of patients, respectively. Odds ratios (ORs) of post- over pretreatment serviceable hearing were 0.42 ( < .01), 0.47 ( = .05), and 0.60 ( = .22); for facial nerve impairment, these ORs were 1.08 ( = .69), 3.45 ( = .28), and 0.87 ( = .71), respectively.
CONCLUSIONS
The management of large VS remains challenging. All treatment modalities resulted in high tumor control rates and worsening of pretreatment hearing. None, however, caused significant facial nerve impairment, suggesting that management strategies incorporating focal irradiation can be successful.
PubMed: 34277019
DOI: 10.1093/nop/npab011 -
Neurosurgical Focus Mar 2018OBJECTIVE Total tumor excision with the preservation of neurological function and quality of life is the goal of modern-day vestibular schwannoma (VS) surgery.... (Meta-Analysis)
Meta-Analysis
Preoperative diffusion tensor imaging-fiber tracking for facial nerve identification in vestibular schwannoma: a systematic review on its evolution and current status with a pooled data analysis of surgical concordance rates.
OBJECTIVE Total tumor excision with the preservation of neurological function and quality of life is the goal of modern-day vestibular schwannoma (VS) surgery. Postoperative facial nerve (FN) paralysis is a devastating complication of VS surgery. Determining the course of the FN in relation to a VS preoperatively is invaluable to the neurosurgeon and is likely to enhance surgical safety with respect to FN function. Diffusion tensor imaging-fiber tracking (DTI-FT) technology is slowly gaining traction as a viable tool for preoperative FN visualization in patients with VS. METHODS A systematic review of the literature in the PubMed, Cochrane Library, and Web of Science databases was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and those studies that preoperatively localized the FN in relation to a VS using the DTI-FT technique and verified those preoperative FN tracking results by using microscopic observation and electrophysiological monitoring during microsurgery were included. A pooled analysis of studies was performed to calculate the surgical concordance rate (accuracy) of DTI-FT technology for FN localization. RESULTS Fourteen studies included 234 VS patients (male/female ratio 1:1.4, age range 17-75 years) who had undergone preoperative DTI-FT for FN identification. The mean tumor size among the studies ranged from 29 to 41.3 mm. Preoperative DTI-FT could not visualize the FN tract in 8 patients (3.4%) and its findings could not be verified in 3 patients (1.2%), were verified but discordant in 18 patients (7.6%), and were verified and concordant in 205 patients (87.1%). CONCLUSIONS Preoperative DTI-FT for FN identification is a useful adjunct in the surgical planning for large VSs (> 2.5 cm). A pooled analysis showed that DTI-FT successfully identifies the complete FN course in 96.6% of VSs (226 of 234 cases) and that FN identification by DTI-FT is accurate in 90.6% of cases (205 of 226 cases). Larger studies with DTI-FT-integrated neuronavigation are required to look at the direct benefit offered by this specific technique in preserving postoperative FN function.
Topics: Data Analysis; Diffusion Tensor Imaging; Facial Nerve; Humans; Microsurgery; Neuroma, Acoustic; Neuronavigation; Preoperative Care
PubMed: 29490547
DOI: 10.3171/2017.12.FOCUS17672 -
The Cochrane Database of Systematic... Dec 2014Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation... (Review)
Review
BACKGROUND
Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation with neuroradiological follow-up, microsurgical resection and stereotactic radiotherapy.
OBJECTIVES
To assess the effect of stereotactic radiotherapy compared to observation, microsurgical resection, any other treatment modality, or a combination of two or more of the above approaches for vestibular schwannoma.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL; Web of Science; CAB Abstracts; ISRCTN and additional sources for published and unpublished trials. The date of the search was 24 July 2014.
SELECTION CRITERIA
Randomised controlled trials (RCTs) exploring the efficacy of stereotactic radiotherapy compared with observation alone, microsurgical resection or any other possible treatment or combination of treatments in patients with a cerebellopontine angle tumour up to 3 cm in diameter, presumed to be a vestibular schwannoma.
DATA COLLECTION AND ANALYSIS
We used the standard methodological procedures expected by The Cochrane Collaboration.
MAIN RESULTS
No studies met the inclusion criteria for this review.
AUTHORS' CONCLUSIONS
There is no high quality evidence in the literature from RCTs to determine whether stereotactic radiotherapy is better than microsurgical resection or observation alone for patients with a vestibular schwannoma. In the absence of such evidence, the treatment method should be chosen on an individual basis, taking into consideration the patient's preferences, clinician experience and the availability of radiotherapeutic equipment. With the growing availability of radiotherapeutic equipment, randomised controlled trials should be undertaken to evaluate the role of stereotactic radiotherapy in comparison with other treatment options.
Topics: Humans; Neuroma, Acoustic; Radiosurgery
PubMed: 25511415
DOI: 10.1002/14651858.CD009897.pub2 -
British Journal of Neurosurgery Apr 2023Vestibular schwannoma is a common pathology encountered by neurosurgeons worldwide. Often vestibular schwannoma presents with obstructive hydrocephalus. Papilledema is... (Review)
Review
BACKGROUND
Vestibular schwannoma is a common pathology encountered by neurosurgeons worldwide. Often vestibular schwannoma presents with obstructive hydrocephalus. Papilledema is present in 8% of the patients with vestibular schwannoma, primarily due to obstructive hydrocephalus. Hyperproteinorrhachia is believed to be responsible for papilledema in the absence of hydrocephalus in vestibular schwannoma. However, there is a paucity of literature on the mechanism of papilledema in vestibular schwannoma patients with hydrocephalus.
OBJECTIVE
The aim of this study was to conduct a scoping review of scientific literature on papilledema in vestibular schwannoma patients without hydrocephalus.
METHODS
Design: This was a systematic scoping review and critical appraisal. Literature Search from PubMed was done following PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) and Joanna Briggs Institute guidelines for conducting and reporting scoping reviews.
RESULTS
A total of seven studies, including eight patients, were identified for inclusion in the review. The studies were heterogeneous in terms of reporting for various variables. All the included studies were case reports, with the earliest publication in 1954 and the latest publication in 2020. The mean age of the patients in the included studies was 35 years, with a minimum age of 20 years and maximum age of 64 years. Approximately 62.5% were females, and 37.5% were males in the included study. Only three studies have studied cerebrospinal fluid (CSF) proteins levels in these patients.
CONCLUSIONS
There is paucity in literature and a lack of evidence to conclusively state hyperproteinorrhachia as an antecedent to the development of papilledema in vestibular schwannoma patients without hydrocephalus. Younger age and female gender are risk factors for developing papilledema in the absence of hydrocephalus in vestibular schwannoma patients. Brainstem compression due to the large size of vestibular schwannoma can still have a patent aqueduct of Sylvius and no obstruction to CSF flow. The development of papilledema in vestibular schwannoma is a complex interplay of multiple factors that must be studied comprehensively for complete understanding.
Topics: Male; Humans; Female; Adult; Young Adult; Middle Aged; Neuroma, Acoustic; Papilledema; Hydrocephalus; Cerebrospinal Fluid Proteins; Cerebral Ventricles
PubMed: 35174747
DOI: 10.1080/02688697.2022.2039376 -
BioRxiv : the Preprint Server For... Apr 2024Auditory nerve (AN) function has been hypothesized to deteriorate with age and noise exposure. Here, we perform a systematic review of published studies and find that...
Auditory nerve (AN) function has been hypothesized to deteriorate with age and noise exposure. Here, we perform a systematic review of published studies and find that the evidence for age-related deficits in AN function is largely consistent across the literature, but there are inconsistent findings among studies of noise exposure history. Further, evidence from animal studies suggests that the greatest deficits in AN response amplitudes are found in noise-exposed aged mice, but a test of the interaction between effects of age and noise exposure on AN function has not been conducted in humans. We report a study of our own examining differences in the response amplitude of the compound action potential N1 (CAP N1) between younger and older adults with and without a self-reported history of noise exposure in a large sample of human participants (63 younger adults 18-30 years of age, 103 older adults 50-86 years of age). CAP N1 response amplitudes were smaller in older than younger adults. Noise exposure history did not appear to predict CAP N1 response amplitudes, nor did the effect of noise exposure history interact with age. We then incorporated our results into two meta-analyses of published studies of age and noise exposure history effects on AN response amplitudes in neurotypical human samples. The meta-analyses found that age effects across studies are robust (r=-0.407), but noise-exposure effects are weak (r=-0.152). We conclude that noise-exposure effects may be highly variable depending on sample characteristics, study design, and statistical approach, and researchers should be cautious when interpreting results. The underlying pathology of age-related and noise-induced changes in AN function are difficult to determine in living humans, creating a need for longitudinal studies of changes in AN function across the lifespan and histological examination of the AN from temporal bones collected post-mortem.
PubMed: 38585917
DOI: 10.1101/2024.03.20.585882 -
Brain Sciences Oct 2021Several electrical stimulation patterns of the auditory nerve have been described for tinnitus relief, but there is no consensus on the most effective stimulation... (Review)
Review
Several electrical stimulation patterns of the auditory nerve have been described for tinnitus relief, but there is no consensus on the most effective stimulation pattern. Therefore, we aim to systematically review the literature on the effect of intra- and extracochlear electrical stimulation patterns as a treatment option for patients with tinnitus. Only studies on intra- and extracochlear electrical stimulation for patients with tinnitus were included if the stimulation used did not concern standardized CI stimulation patterns to primarily rehabilitate hearing loss as intervention. A total of 34 studies met the inclusion criteria, with 10 studies (89 patients) on intracochlear electrical stimulation and 25 studies on extracochlear electrical stimulation (1109 patients). There was a high to medium risk of bias in 22 studies, especially due to lack of a non-exposed group and poor selection of the exposed group. All included studies showed subjective tinnitus improvement during or after electrical stimulation, using different stimulation patterns. Due to methodological limitations and low reporting quality of the included studies, the potential of intra- and extracochlear stimulation has not been fully explored. To draw conclusions on which stimulation patterns should be optimized for tinnitus relief, a deeper understanding of the mechanisms involved in tinnitus suppression is needed.
PubMed: 34827395
DOI: 10.3390/brainsci11111394