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The Journal of International Advanced... Sep 2021Vestibular schwannomas (VS) frequently lead to ipsilateral sensorineural hearing loss (HL) as part of its natural history or as a result of treatment. Cochlear...
BACKGROUND AND OBJECTIVES
Vestibular schwannomas (VS) frequently lead to ipsilateral sensorineural hearing loss (HL) as part of its natural history or as a result of treatment. Cochlear implantation represents a well-documented treatment of profound HL that cannot be treated adequately with a conventional hearing aid, thus being offered to selected VS patients. A functional cochlea and cochlear nerve are prerequisites for sound perception with a cochlear implant (CI). The potential impact of radiotherapy on these structures is thus an important issue for subsequent CI hearing outcomes. The objective of this article is to present a case and to review the existing literature on the outcomes of cochlear implantation in irradiated VS patients systematically.
METHODS
A systematic literature review using preferred reporting items for systematic reviews and meta-analyses was conducted. Medline was searched systematically. Papers reporting ipsilateral CI outcomes after radiotherapy of VS were included. Additionally, results of CI after stereotactic radiotherapy in a 54-year-old male with neurofibromatosis type 2 are presented.
RESULTS
A total of 14 papers (33 patients) fulfilled inclusion criteria. Moderate preoperative HL was found in 11 patients. Six had moderate to severe HL, whereas 16 had severe HL or total deafness. Postoperative hearing outcomes varied from poor in 27% of patients to excellent in 19%, with remaining cases lying in between (mean follow-up of 19 months). Most patients achieved improvement in hearing and quality of life.
CONCLUSION
Despite variation in the degree of hearing outcome, CI after radiotherapy of VS appears to be effective in the majority of cases, as more than 70% of patients have good or excellent outcomes within 1-2 years post-implantation. Subjective benefits are considerable, even in cases with relatively poor objective outcome.
Topics: Cochlear Implantation; Cochlear Implants; Hearing Loss, Sensorineural; Humans; Male; Middle Aged; Neuroma, Acoustic; Quality of Life; Speech Perception; Treatment Outcome
PubMed: 34617898
DOI: 10.5152/iao.2021.21008 -
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 -
La Clinica Terapeutica May 2021Over the process of establishing the causal relation-ship, medical and legal methodologies may be at variance over the definitional standards and terminologies applied,...
Can a causal relationship be established between acoustic neuroma and occupational exposure to non-ionizing radiations from mobile devices? Comparison between scientific literature data and medico-legal methodology.
BACKGROUND
Over the process of establishing the causal relation-ship, medical and legal methodologies may be at variance over the definitional standards and terminologies applied, which can hinder the activities of expert witnesses.
OBJECTIVES
The article's authors have set out to assess whether, and under what conditions, a causal relationship can be established between acoustic neuroma and exposure to non-ionizing radiation from mobile communication devices.
METHODS
The study design is a Systematic Review. The authors have drawn upon a 2020 Turin Court of Appeals ruling which found such a causal relationship in a somewhat peculiar case: rare tumor and exposure to non-ionizing radiation of unusually long and regular dura-tion. The case presents several peculiarities, herein analyzed in light of a) scientific evidence relative to the etiopathogenesis of the neuroma; b) available medico-legal literature defining causality evaluation criteria, and lastly c) court filings in regard to the probability standards applied to prove causal relationship.
RESULTS
A direct tie cannot be proven, not even in cases of sub-stantially intense and lengthy exposure, if the medico-legal standards applied are not consistent enough to prove that nexus is more likely than not.
DISCUSSION
Several elements suggest a causal relationship is unlikely: a) a dearth of evidence on humans; b) rats exposed to such radiation have developed cardiac tumors, not in their ears; c) exposure has caused no tumors in mice; d) the length of exposure is incompat-ible with tumor size and type. That fourth point only concerns the case herein explored, whereas the first three have a general scope of validity. The main limitation of the present study design is the heterogeneity among the included studies. Retrospective and prospective studies have been included, which may be a source of bias.
Topics: Animals; Causality; Computers, Handheld; Humans; Mice; Neuroma, Acoustic; Occupational Exposure; Radiation, Nonionizing; Rats; Risk Factors
PubMed: 33956036
DOI: 10.7417/CT.2021.2313 -
Neurosurgical Review Dec 2021Vestibular schwannomas (VS) are slow-growing intracranial extraaxial benign tumors, developing from the vestibular part of the eight cranial nerves. Stereotactic... (Meta-Analysis)
Meta-Analysis Review
Vestibular schwannomas (VS) are slow-growing intracranial extraaxial benign tumors, developing from the vestibular part of the eight cranial nerves. Stereotactic radiosurgery (SRS) has now a long-term scientific track record as first intention treatment for small- to medium-sized VS. Though its success rate is very high, SRS for VS might fail to control tumor growth in some cases. However, the literature on repeat SRS after previously failed SRS remains scarce and reported in a low number of series with a limited number of cases. Here, we aimed at performing a systematic review and meta-analysis of the literature on repeat SRS for VS. Using PRISMA guidelines, we reviewed manuscripts published between January 1990 and October 2020 and referenced in PubMed. Tumor control and cranial nerve outcomes were evaluated with separate meta-analyses. Eight studies comprising 194 patients were included. The overall rate of patients treated in repeat SRS series as per overall series with first SRS was 2.2% (range 1.2-3.2%, p < 0.001). The mean time between first and second SRS was 50.7 months (median 51, range 44-64). The median marginal dose prescribed at first SRS was 12 Gy (range 8-24) and at second SRS was 12 Gy (range 9.8-19). After repeat SRS, tumor stability was reported in 61/194 patients, i.e., a rate of 29.6% (range 20.2-39%, I = 49.1%, p < 0.001). Tumor decrease was reported in 83/194 patients, i.e., a rate of 54.4% (range 33.7-75.1%, I = 89.1%, p < 0.001). Tumor progression was reported in 50/188 patients, i.e., a rate of 16.1% (range 2.5-29.7%, I = 87.1%, p = 0.02), rarely managed surgically. New trigeminal numbness was reported in 27/170 patients, i.e., a rate of 9.9% (range 1.4-18.3%, p < 0.02). New facial nerve palsy of worsened of previous was reported in 8/183 patients, i.e., a rate of 4.3% (range 1.4-7.2%, p = 0.004). Hearing loss was reported in 12/22 patients, i.e., a rate of 54.3% (range 24.8-83.8%, I = 70.7%, p < 0.001). Repeat SRS after previously failed SRS for VS is associated with high tumor control rates. Cranial nerve outcomes remain favorable, particularly for facial nerve. The rate of hearing loss appears similar to the one related to first SRS.
Topics: Facial Nerve; Follow-Up Studies; Humans; Neuroma, Acoustic; Radiosurgery; Retrospective Studies; Treatment Outcome
PubMed: 33847846
DOI: 10.1007/s10143-021-01528-y -
European Archives of... Oct 2021Postoperative headache (POH) is a complication that occurs after surgical resection of cerebellopontine angle (CPA) tumors. The two most common surgical approaches are...
PURPOSE
Postoperative headache (POH) is a complication that occurs after surgical resection of cerebellopontine angle (CPA) tumors. The two most common surgical approaches are the translabyrinthine (TL), and retrosigmoid (RS) approach. The objective of this systematic review was to investigate whether POH occurs more frequently after RS compared to TL approaches.
METHODS
A systematic search was conducted in Cochrane, Pubmed and Embase. Studies were included if POH after CPA tumor removal was reported and both surgical approaches were compared. The methodological quality of the studies was assessed using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool.
RESULTS
In total, 3,942 unique articles were screened by title and abstract. After the initial screening process 63 articles were screened for relevance to the inquiry, of which seven studies were included. Three studies found no significant difference between both surgical approaches (p = 0.871, p = 0.120, p = 0.592). Three other studies found a lower rate of POH in the TL group compared to the RS group (p = 0.019, p < 0.001, p < 0.001). Another study showed a significantly lower POH rate in the TL group after one and six months (p = 0.006), but not after 1 year (p = 0.6).
CONCLUSION
The results of this systematic review show some evidence of a lower rate of POH in favor of the TL approach versus the RS approach for CPA tumor resection. Prospective research studies are needed to further investigate this finding.
Topics: Cerebellopontine Angle; Headache; Humans; Neuroma, Acoustic; Neurosurgical Procedures; Postoperative Complications
PubMed: 33523284
DOI: 10.1007/s00405-021-06627-6 -
Journal of Neurological Surgery. Part... Jun 2022The center of excellence model of health care hypothesizes that increased volume in a specialized center will lead to better and more affordable care. We sought to...
The center of excellence model of health care hypothesizes that increased volume in a specialized center will lead to better and more affordable care. We sought to characterize the volume-outcome data for surgically treated sinonasal and skull base tumors and (chemo) radiation-treated nasopharyngeal malignancy. Systematic review of the literature. This review included national database and multi-institutional studies published between 1990 and 2019. PubMed was interrogated for keywords "hospital volume," "facility volume," and outcomes for "Nasopharyngeal carcinoma," "Sinonasal carcinomas," "Pituitary Tumors," "Acoustic Neuromas," "Chordomas," and "Skull Base Tumors" to identify studies. Single-institution studies and self-reported surveys were excluded. The main outcome of interest in malignant pathologies was survival; and in benign pathologies it was treatment-related complications. A total of 20 studies met inclusion criteria. The average number of patients per study was 4,052, and ranged from 394 to 9,950 patients. Six of seven studies on malignant pathology demonstrated improved survival with treatment in high volume centers and one showed no association with survival. Ten of thirteen studies on benign disease showed reduced risk of complications, while one study demonstrated both an increased and decreased association of complications. Two studies showed no volume-outcome associations. This systematic review demonstrates that a positive volume-outcome relationship exists for most pathologies of the skull base, with some exceptions. The relative dearth of literature supports further research to understand the effect of centralization of care on treatment outcomes.
PubMed: 35769793
DOI: 10.1055/s-0040-1721823 -
Neurosurgical Review Aug 2021Intramedullary schwannomas (IMS) represent exceptional rare pathologies. They commonly present as solitary lesions; only five cases of multiple IMS have been described... (Review)
Review
Intramedullary schwannomas (IMS) represent exceptional rare pathologies. They commonly present as solitary lesions; only five cases of multiple IMS have been described so far. Here, we report the sixth case of a woman with multiple IMS. Additionally, we performed the first complete systematic review of the literature for all cases reporting IMS. We performed a systematic review of the literature in PubMed, EMBASE and Cochrane Central Register of Controlled (CENTRAL) to retrieve all relevant studies and case reports on IMS. In a second step, we analysed all reported studies with respect to additional cases, which were not identified through the database search. Studies published in other languages than English were included. One hundred nineteen studies including 165 reported cases were included. In only five cases, the patients harboured more than one IMS. Gender ratio showed a ratio of nearly 3:2 (male:female); mean age of disease presentation was 40.2 years; 11 patients suffered from neurofibromatosis (NF) type 1 or 2 (6.6%). IMS are rare. Our first systematic review on this pathology revealed 166 cases, including the here reported case of multiple IMS. Our review offers a basis for further investigation on this disease.
Topics: Female; Humans; Neurilemmoma; Neurofibromatosis 1; Neurofibromatosis 2; Spine
PubMed: 32935226
DOI: 10.1007/s10143-020-01357-5 -
Stereotactic and Functional Neurosurgery 2021Trigeminal neuralgia (TN) secondary to tumors is encountered in up to 6% of patients with facial pain syndromes and is considered to be associated with tumors affecting... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Trigeminal neuralgia (TN) secondary to tumors is encountered in up to 6% of patients with facial pain syndromes and is considered to be associated with tumors affecting the trigeminal nerve pathways. The most frequent are meningiomas and vestibular schwannomas (VS). Stereotactic radiosurgery (SRS) has emerged as a valuable treatment, with heterogeneity of clinical results. We sought to review the medical literature on TN treated with SRS for meningiomas and VS and investigate the rates of improvement of TN symptoms.
METHODS
We reviewed articles published between January 1990 and December 2019 in PubMed. Pain relief after SRS, the maintenance of pain relief, and TN recurrence and complications were evaluated with separate meta-analyses, taking into account the data on individual patients.
RESULTS
Pain relief after SRS was reported as Barrow Neurological Institute (BNI) pain intensity scores of BNI I in 50.5% (range 36-65.1%) of patients and BNI I-IIIb in 83.8% (range 77.8-89.8%). There was no significant difference in series discussing outcomes for tumor targeting versus tumor and nerve targeting. Recurrences were described in 34.7% (range 21.7-47.6; tumor targeting). Maintenance of BNI I was reported in 36.4% (range 20.1-52.7) and BNI I-IIIb in 41.2% (range 29.8-52.7; tumor targeting series). When both the nerve and the tumor were targeted, only 1 series reported 86.7% with BNI I-IIIb at last follow-up. Complications were encountered in 12.6% (range 6.3-18.8; tumor targeting series) of patients; however, they were much higher, as high as 26.7%, in the only study reporting them after targeting both the nerve and the tumor. The most common complication was facial numbness.
CONCLUSION
SRS for TNB secondary to benign tumors, such as meningiomas and VS, is associated with favorable clinical course, but less favorable than in idiopathic TN. There was, however, heterogeneity among reports and targeting approaches. Although targeting both the nerve and the tumor seemed to achieve better long-term results, the rate of complications was much higher and the number of patients treated was limited. Future clinical studies should focus on the standard reporting of clinical outcomes and randomization of targeting methods.
Topics: Humans; Meningeal Neoplasms; Meningioma; Neuroma, Acoustic; Pain Management; Radiosurgery; Retrospective Studies; Treatment Outcome; Trigeminal Neuralgia
PubMed: 32906130
DOI: 10.1159/000509842 -
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 -
Journal of Neurological Surgery. Part... Dec 2019This study was aimed to perform a systematic literature review by examining outcomes in patients with sporadic vestibular schwannoma (VS) undergoing ipsilateral...
This study was aimed to perform a systematic literature review by examining outcomes in patients with sporadic vestibular schwannoma (VS) undergoing ipsilateral cochlear implant (CI). PubMed-NCBI (National Center for Biotechnology Information) and Scopus databases were searched through October 2017. Studies reporting auditory outcomes for each patient when a CI was placed with an ipsilateral sporadic VS were included. Demographic variables, VS characteristics, preoperative hearing metrics, duration of deafness, CI type, approach to tumor resection, postoperative auditory outcomes, and postoperative tinnitus outcomes were reported for each eligible patient within studies. Each study was evaluated for quality and bias. Fifteen studies and 45 patients met inclusion criteria. Mean speech discrimination score (SDS) improved from 30.0 to 56.4% after CI placement. The majority when reported had an improvement in tinnitus. Preoperative ipsilateral SDS was a negative predictor of postoperative SDS, while neither tumor resection status, tumor location, duration of deafness, ipsilateral pure tone average, nor timing of CI placement had a significant effect on patient outcome. Notwithstanding the challenges inherent with surveillance magnetic resonance imaging (MRI) in the setting of a cochlear implant magnet, select sporadic vestibular schwannoma patients can be considered for cochlear implantation.
PubMed: 31750050
DOI: 10.1055/s-0038-1676768