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World Neurosurgery Feb 2021The popularization and application of microscopy, the in-depth study of the microanatomy of the cerebellopontine angle, and the application of intraoperative... (Meta-Analysis)
Meta-Analysis
Reliability of Preoperative Prediction of the Location of the Facial Nerve Using Diffusion Tensor Imaging-Fiber Tracking in Vestibular Schwannoma: A Systematic Review and Meta-Analysis.
The popularization and application of microscopy, the in-depth study of the microanatomy of the cerebellopontine angle, and the application of intraoperative electrophysiological monitoring technology to preserve facial nerve function have laid a solid foundation for the modern era of neurosurgery. The preoperative prediction of the location of the facial nerve is a long-desired goal of neurosurgeons. The advances in neuroimaging seem to be making this goal a reality. Many studies investigating the reliability of the preoperative prediction of the location of the facial nerve using diffusion tensor imaging-fiber tracking in vestibular schwannoma have been reported in the last 20 years. The PubMed, Embase, and Cochrane databases were searched for articles published before March 30, 2020. A comprehensive review of published studies was carried out in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Authors performed a systematic review and meta-analysis of the reported data to assess the reliability of the preoperative prediction of the location of the facial nerve using diffusion tensor imaging-fiber tracking in vestibular schwannoma. The data were analyzed using a fixed-effects model. The estimated overall intraoperative verification concordance rate was 89.05% (95% confidence interval 85.06%-92.58%). Preoperatively predicting the location of the facial nerve using diffusion tensor imaging-fiber tracking in vestibular schwannoma is reliable, but the extent to which it contributes to long-term facial nerve function is still unclear. To further verify these results, studies with larger sample sizes are needed in the future, especially prospective randomized controlled trials focusing on the long-term functional preservation of the facial nerve.
Topics: Diffusion Tensor Imaging; Facial Nerve; Facial Nerve Injuries; Humans; Intraoperative Complications; Neuroma, Acoustic; Neurosurgical Procedures; Preoperative Care; Reproducibility of Results
PubMed: 33130136
DOI: 10.1016/j.wneu.2020.10.136 -
World Neurosurgery May 2021Surveillance imaging is a valid management option for selected vestibular schwannomas (VS). An ideal protocol for radiologic monitoring would highlight growth-related...
BACKGROUND
Surveillance imaging is a valid management option for selected vestibular schwannomas (VS). An ideal protocol for radiologic monitoring would highlight growth-related risk factors and tailor management accordingly. This study aims to identify variables associated with the growth of sporadic VS to enhance surveillance imaging, enable early intervention, and optimize outcomes.
METHODS
The review was conducted according to the PRISMA guidelines. A systematic review of 5 databases (PubMed, Ovid, Cochrane Library, Web of Science, and Google Scholar) was performed to identify negative and positive growth predictors of sporadic vestibular schwannomas. The search was limited to studies reported between January 2015 and January 2020. We conducted an individual patient data meta-analysis using a 1-stage multivariate mixed-effect logistic regression model.
RESULTS
A total of 437 studies were identified, of which 25 met our criteria for full-text analysis. Articles that measured VS with comparable methods were determined eligible for meta-analysis inclusion. The selected articles were highly heterogeneous in their use of grading scales and assessment of tumor size. Our review showed that size at diagnosis (odds ratio, 1.15; 95% confidence interval, 1.11-1.18; P < 0.0001) and intracanalicular localization (odds ratio, 0.49; 95% confidence interval, 0.26-0.90; P = 0.023) were associated with VS growth.
CONCLUSIONS
The factors most frequently reported as being associated with growth within the literature were size of VS at diagnosis and localization of an intracanalicular component. Greater attention should be placed on these criteria within the surveillance imaging algorithm for VS.
Topics: Aged; Aged, 80 and over; Female; Humans; Male; Neurilemmoma; Neuroma, Acoustic; Patients; Quality of Life; Radiosurgery
PubMed: 33540091
DOI: 10.1016/j.wneu.2021.01.101 -
European Archives of... Jan 2024To review the literature on intratympanic gentamicin treatment as prehabilitation for patients undergoing surgery for a unilateral vestibular schwannoma. (Review)
Review
The effect of intratympanic gentamicin as a prehabilitation strategy for objective and subjective vestibular function in patients undergoing microsurgery for a unilateral vestibular schwannoma.
OBJECTIVE
To review the literature on intratympanic gentamicin treatment as prehabilitation for patients undergoing surgery for a unilateral vestibular schwannoma.
DATA SOURCES
A systematic literature search was conducted up to March 2023 in Pubmed, Embase, Cochrane, Web of Science, Academic Search Premier, Google Scholar and Emcare databases.
REVIEW METHODS
Articles on the effect of intratympanic gentamicin followed by vestibular schwannoma surgery were reviewed. Data on objective vestibular function and subjective outcomes were compiled in tables for analysis. Relevance and methodological quality were assessed with the methodological index for non-randomized tool.
RESULTS
A total of 281 articles were identified. After screening and exclusion of duplicates, 13 studies were reviewed for eligibility, of which 4 studies could be included in the review. The posturography test, the subjective visual horizontal test, and the optokinetic nystagmus test showed decreased vestibular function in the group of patients who received intratympanic gentamicin before microsurgery compared to the group of patients without gentamicin. Other objective tests did not show significant differences between patient groups. Subjective vestibular outcomes, as evaluated by questionnaires on quality of life and/or dizziness, did not seem to improve from intratympanic gentamicin pretreatment.
CONCLUSION
Vestibular schwannoma patients who received intratympanic gentamicin before surgical resection of the tumor performed better in the posturography test, subjective visual horizontal test, and the optokinetic nystagmus test afterwards. However, studies that also evaluated subjective outcomes such as dizziness, anxiety, depression, and balance self-confidence did not show a positive effect of intratympanic gentamicin on the vestibular complaints and symptoms.
Topics: Humans; Dizziness; Gentamicins; Microsurgery; Neuroma, Acoustic; Preoperative Exercise; Quality of Life; Vertigo
PubMed: 37750993
DOI: 10.1007/s00405-023-08240-1 -
Journal of Clinical Neurology (Seoul,... May 2023Vestibular schwannoma (VS) is the most common type of tumor found in the cerebellopontine angle that accounts for 8% of all intracranial tumors. VS management is...
BACKGROUND AND PURPOSE
Vestibular schwannoma (VS) is the most common type of tumor found in the cerebellopontine angle that accounts for 8% of all intracranial tumors. VS management is currently a challenge due to the unpredictable nature of the tumor. Few studies have compared the results and complications of various therapeutic approaches to VS. Therefore, as a treatment option for VSs smaller than 25 mm, we conducted a systematic review to compare Gamma Knife radiosurgery (GKRS) with conventional surgery.
METHODS
Literature searches were conducted of four online databases (PubMed, Google Scholar, Cochrane, and ScienceDirect) using the following keyword search: ("vestibular schwannoma" OR "acoustic neuroma") AND ("gamma knife" OR "gamma knife radiosurgery") AND ("resection" OR "open surgery") AND ("hearing preservation" OR "facial nerve" OR "tumor growth").
RESULTS
We identified six retrospective cohort studies, five of which were of fair-to-good quality. All studies showed that GKRS was superior to surgery in hearing preservation. Two studies indicated that surgery was superior to GKRS in maintaining tumor control, one indicated that GKRS was superior, and the remainder indicated that there was no significant difference in maintaining tumor control between GKRS and microsurgery.
CONCLUSIONS
Based on the three outcomes chosen for this review, GKRS was superior to microsurgery in small VS.
PubMed: 36647227
DOI: 10.3988/jcn.2022.0116 -
Neurosurgical Review Nov 2023The accurate identification and preservation of the facial nerve (FN) during vestibular schwannoma (VS) surgery is crucial for maintaining facial function. Investigating...
The accurate identification and preservation of the facial nerve (FN) during vestibular schwannoma (VS) surgery is crucial for maintaining facial function. Investigating the application of diffusion tensor imaging (DTI) in preoperative planning for large VS surgery is provided. PubMed, Cochrane Library, Science Direct, ISI Web of Science, Embase, and additional sources were searched to identify cohort studies about the preoperative DTI usage for the FN tracking before large VS (≥ 2.5 cm) surgery published between 1990 and 2023. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed; the Newcastle-Ottawa Scale was used to assess the risk of bias and to evaluate limitations based on selection/outcome biases. A total of 8 publications yielding 149 VS (mean size 3.66 ± 0.81 cm) were included. Surgical concordance with preoperative DTI FN tracking was 91.67% (range 85-100%). Overall DTI reliability was 88.89% (range 81.81-95.83%). Larger tumor size predicted either DTI inaccurate finding or complete DTI failure (p = 0.001). VS size above > 3.5 cm was associated with a higher risk of DTI failure (p = 0.022), with a higher risk of inaccurate DTI finding preoperatively (p = 0.033), and with a higher House-Brackman score postoperatively (p = 0.007). Application of DTI in larger VS surgery is a valuable FN identification along with electrophysiological monitoring and neuronavigation, therefore also in its preservation and in lowering risk of complications. DTI represents a valuable adjunct to electrophysiological monitoring and neuronavigation in FN identification, applicable not only for smaller, but also larger VS.
Topics: Humans; Facial Nerve; Diffusion Tensor Imaging; Neuroma, Acoustic; Reproducibility of Results; Facial Nerve Injuries
PubMed: 37950058
DOI: 10.1007/s10143-023-02214-x -
Clinical Neurology and Neurosurgery Jun 2020Vestibular schwannomas can be treated in different ways, but for symptomatic or growing tumors, the gold standard is surgical removal of the lesion. In order to preserve... (Meta-Analysis)
Meta-Analysis
Vestibular schwannomas can be treated in different ways, but for symptomatic or growing tumors, the gold standard is surgical removal of the lesion. In order to preserve neurovascular structures, partial removal is often performed, leaving a residual that may grow in subsequent years. To date, there is no consensus with regard to surgical treatment of vestibular schwannoma residuals, and so this review focuses on this topic. A structured search was performed on PubMed searching for all articles discussing vestibular schwannoma residuals and recurrences. Only articles discussing surgical treatment were included, focusing on studies which also examined facial nerve outcomes. A total of 51 articles were eligible for review and these included 375 patients. Statistical analysis was performed by correlating the following parameters: patients' gender and age at first surgery, surgical approach adopted at first and subsequent surgeries, tumor and residual size, and extent of resection (gross total, near total, subtotal or others) at first and subsequent surgical procedures. Facial nerve function was also analyzed focusing on its performance when correlated with the different surgical approaches. The data were analyzed by linear regression but there were no correlations between any of the parameters chosen. There was a statistically significant difference between the first approach used (mainly the retrosigmoid route) compared with subsequent approaches (mainly the translabyrinthine route). In total, 8.5 % of patients needed further treatment due to residual regrowth. Facial nerve outcome was independent of the parameters chosen. Exclusive surgical treatment for vestibular schwannoma residuals had a very low failure rate in terms of requiring further treatment. The approach usually chosen for second surgery was the translabyrinthine technique, and this may be explained by the location of the residual, rather than its size. The choice of a particular surgical approach rather than another had no influence on facial nerve function. Complications rates are comparable to Gamma Knife Radiosurgery's as reported in the literature.
Topics: Humans; Neoplasm Recurrence, Local; Neuroma, Acoustic; Neurosurgical Procedures; Treatment Outcome
PubMed: 32146233
DOI: 10.1016/j.clineuro.2020.105769 -
Journal of Neuro-oncology Nov 2019Communicating hydrocephalus (cHCP) after radiosurgery (RS) for vestibular schwannomas (VS) has been reported. Many hypothetical mechanisms for this pathology have been... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Communicating hydrocephalus (cHCP) after radiosurgery (RS) for vestibular schwannomas (VS) has been reported. Many hypothetical mechanisms for this pathology have been proposed without consensus. The aim of this study is to determine if the platform used to treat the disease, Gamma Knife (GK) versus linear accelerator (LINAC)-based RS, makes a difference in outcome.
METHODS
We conducted a meta-analysis of databases PubMed and Cochrane to identify all articles for the period January 2000-August 2018 with the following inclusion criteria: (1) VS treated with single fraction SRS (2) > 10 patients (3) original reports only (4) hydrocephalus reported as complication (5) human study.
RESULTS
A total of 7039 and 988 VS patients reported in 35 and 10 papers were treated with GK or LINAC RS, respectively. Demographic baseline characteristics not reported in aggregate did not differ between the two groups. The incidence of cHCP was 3% [95% CI 2-4] and 2% [95% CI 1-3] for GK and LINAC RS patients, respectively. Surgical CSF diversion was performed in 88% and 68% of patients evaluated for cHPC in the GK and LINAC group, respectively. Follow-up range was 30-150 and 29-92 months for GK and LINAC, respectively.
CONCLUSIONS
The incidence of cHCP following RS for VS is very low in both GK and LINAC treated patients, albeit not identical. The higher reported surgical intervention rate for VS patients treated with GK RS might be multi-factorial, including longer follow-up in the GK group.
Topics: Humans; Hydrocephalus; Neuroma, Acoustic; Radiosurgery; Treatment Outcome
PubMed: 31621039
DOI: 10.1007/s11060-019-03305-w -
Acta Neurochirurgica Nov 2020The optimal management of large vestibular schwannomas continues to be debated. We constituted a task force comprising the members of the EANS skull base committee along... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND OBJECTIVE
The optimal management of large vestibular schwannomas continues to be debated. We constituted a task force comprising the members of the EANS skull base committee along with international experts to derive recommendations for the management of this problem from a European perspective.
MATERIAL AND METHODS
A systematic review of MEDLINE database, in compliance with the PRISMA guidelines, was performed. A subgroup analysis screening all surgical series published within the last 20 years (January 2000 to March 2020) was performed. Weighted summary rates for tumor resection, oncological control, and facial nerve preservation were determined using meta-analysis models. This data along with contemporary practice patterns were discussed within the task force to generate consensual recommendations regarding preoperative evaluations, optimal surgical strategy, and follow-up management.
RESULTS
Tumor classification grades should be systematically used in the perioperative management of patients, with large vestibular schwannomas (VS) defined as > 30 mm in the largest extrameatal diameter. Grading scales for pre- and postoperative hearing (AAO-HNS or GR) and facial nerve function (HB) are to be used for reporting functional outcome. There is a lack of consensus to support the superiority of any surgical strategy with respect to extent of resection and use of adjuvant radiosurgery. Intraoperative neuromonitoring needs to be routinely used to preserve neural function. Recommendations for postoperative clinico-radiological evaluations have been elucidated based on the surgical strategy employed.
CONCLUSION
The main goal of management of large vestibular schwannomas should focus on maintaining/improving quality of life (QoL), making every attempt at facial/cochlear nerve functional preservation while ensuring optimal oncological control, thereby allowing to meet patient expectations. Despite the fact that this analysis yielded only a few Class B evidences and mostly expert opinions, it will guide practitioners to manage these patients and form the basis for future clinical trials.
Topics: Consensus; Hearing; Humans; Microsurgery; Neuroma, Acoustic; Neurosurgical Procedures; Postoperative Complications; Quality of Life; Radiosurgery; Skull Base; Treatment Outcome
PubMed: 32728903
DOI: 10.1007/s00701-020-04491-7 -
Otology & Neurotology : Official... Jun 2020To determine short- and intermediate-term hearing preservation rates after microsurgical resection of vestibular schwannoma (VS).
OBJECTIVE
To determine short- and intermediate-term hearing preservation rates after microsurgical resection of vestibular schwannoma (VS).
DATA SOURCES
Systematic review of the Ovid, Cochrane, EMBASE, and Web of Science databases.
STUDY SELECTION
This study was restricted to full-text English-language articles detailing VS resection via the middle cranial fossa or retrosigmoid approaches. Documentation of pre- and posttreatment hearing outcomes with American Academy of Otolaryngology-Head and Neck Surgery, Gardner-Robertson, or word recognition score scales, as well as time to follow-up were required. Duplicate data sets, studies with >10% of patients with neurofibromatosis two, previous or nonsurgical VS treatment, case reports with
DATA EXTRACTION
Two authors independently performed full-text reviews to determine study eligibility. Discrepancies were settled by consensus. "Class A/B, I/II" hearing was defined as AAO-HNS Class A or B, Gardner-Robertson Class 1 or 2, or PTA ≤ 50 dB with word recognition score ≥ 50% on audiogram.
DATA SYNTHESIS
Pooled estimates of preserved Class A/B, I/II hearing at last postoperative follow-up.
CONCLUSIONS
Of 1323 reports, 14 were utilized in analyses yielding data from 2,977 patients. Mean follow-up was 52.5 months (SD = 19.9). Class A/B, 1/2 hearing was preserved at last follow-up in 57% of patients. Meta-regression revealed that resection through the middle cranial fossa was associated with preservation of serviceable hearing. Moreover, when preserved in the immediate postoperative period, it seems to be stable over time.
Topics: Cranial Fossa, Middle; Hearing; Hearing Tests; Humans; Microsurgery; Neuroma, Acoustic; Retrospective Studies; Treatment Outcome
PubMed: 32150025
DOI: 10.1097/MAO.0000000000002598 -
Neurosurgery Mar 2020Vestibular schwannomas (VS) are benign tumors derived from Schwann cells ensheathing the vestibulocochlear nerve. The retrosigmoid (RS) surgical approach is useful to...
BACKGROUND
Vestibular schwannomas (VS) are benign tumors derived from Schwann cells ensheathing the vestibulocochlear nerve. The retrosigmoid (RS) surgical approach is useful to resect tumors of multiple sizes while affording the possibility of preserving postoperative hearing.
OBJECTIVE
To conduct a systematic review of published literature investigating hearing preservation rates in patients who underwent the RS approach for VS treatment.
METHODS
The PubMed, Scopus, and Embase databases were surveyed for studies that reported preoperative and postoperative hearing grades on VS patients who underwent RS treatment. Hearing preservation rates were calculated, and additional patient demographic data were extracted. Tumor size data were stratified to compare hearing preservation rates after surgery for intracanalicular, small (0-20 mm), and large (>20 mm) tumors.
RESULTS
Of 383 deduplicated articles, 26 studies (6.8%) met eligibility criteria for a total of 2034 patients with serviceable preoperative hearing, for whom postoperative hearing status was evaluated. Aggregate hearing preservation was 31% and 35% under a fixed and random effects model, respectively. A mixed effects model was used to determine hearing preservation rates depending on tumor size, which were determined to be 57%, 37%, and 12% for intracanalicular, small, and large tumors, respectively. Significant cross-study heterogeneity was found (I2 = 93%, τ2 = .964, P < .01; Q = 287.80, P = < .001), with rates of hearing preservation ranging from 0% to 100%.
CONCLUSION
Tumor size may have an effect on hearing preservation rates, but multiple factors should be considered. Discussion of a patient's expectations for hearing preservation is critical when deciding on VS treatment plans.
Topics: Craniotomy; Hearing; Humans; Neuroma, Acoustic; Postoperative Complications; Postoperative Period; Treatment Outcome
PubMed: 31149722
DOI: 10.1093/neuros/nyz147