Hearing preservation and quality of life in small to medium sized vestibular schwannomas after a wait and scan approach or stereotactic radiosurgery: a systematic review and meta-analysis.

BACKGROUND: The management of vestibular schwannomas (VS) encompasses a choice between conservative "wait-and-scan" (WAS) approach, stereotactic radiosurgery (SRS) or open microsurgical resection. Currently, there is no consensus on the optimal management approach for small to medium sized VS. This study aims to compared outcomes related to hearing in patients with small and medium sized VS who underwent initial treatment with WAS versus SRS. METHODS: A systematic review of the available literature was conducted using PubMed/MEDLINE, Embase, and Cochrane up December 08, 2023. Meta-analysis was performed using a random-effect model to calculate mean difference (MD) and relative risk (RR). A leave-one-out analysis was conducted. The risk of bias was assessed via the Risk of Bias in Non-randomized Studies-Interventions (ROBINS-I) and Cochrane Risk of Bias assessment tool (RoB-2). Ultimately, the certainty of evidence was evaluated using the GRADE assessment. The primary outcomes were serviceable hearing, and pure-tone average (PTA). The secondary outcome was the Penn Acoustic Neuroma Quality of Life Scale (PANQOL) total score. RESULTS: Nine studies were eligible for inclusion, comprising a total of 1,275 patients. Among these, 674 (52.86%) underwent WAS, while 601 patients (47.14%) received SRS. Follow-up duration ranged from two to eight years. The meta-analysis indicated that WAS had a better outcome for serviceable hearing (0.47; 95% CI: 0.32 - 0.68; p < 0.001), as well as for postoperative functional measures including PTA score (MD 13.48; 95% CI 3.83 - 23.13; p < 0.01), and PANQOL total score (MD 3.83; 95% CI 0.42 - 7.25; p = 0.03). The overall certainty of evidence ranged from "very low" to "moderate". CONCLUSIONS: Treating small to medium sized VS with WAS increases the likelihood of preserving serviceable hearing and optimized PANQOL overall postoperative score compared to SRS. Nevertheless, the limited availability of literature and the methodological weakness observed in existing studies outline the need for higher-quality studies.

Hearing Function after CyberKnife for Vestibular Schwannoma: A Systematic Review.

Introduction CyberKnife (CK) radiosurgery is a treatment strategy for vestibular schwannoma (VS). Objectives To evaluate hearing preservation (HP) after CK for VS. Data Synthesis The study was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, and it was registered at the International Prospective Register of Systematic Reviews (PROSPERO, under number CRD42021250300). The inclusion criteria were based on the population, intervention, comparison, outcome, timing and study design (PICOTS) strategy: population - patients with VS; intervention - CK; Comparison - none; Outcome - serviceable HP defined by Gardner and Robertson as grades I or II, or by the American Academy of Otolaryngology and Head and Neck Surgery as classes A or B; timing - mean follow-up longer than 1 year; and study design - retrospective or prospective studies. The exclusion criteria were: studies not published in English; studies published before January 2000 and after October 2021; and studies only including patients with neurofibromatosis type 2 or submitted to a previous treatment. The PubMed/MEDLINE, EMBASE, Web of Science, Cochrane Library, LILACS, and IBECS databases were used and last searched on October 27th, 2021. Statistical heterogeneity was assessed using I 2 statistics. The appraisal checklist was used to assess the risk of bias in the included studies. A total of 222 studies were analyzed, and 13 were included in the synthesis, which represents 493 participants with serviceable hearing before intervention. The mean HP rate after CK using a random effects model was of 68% (95% confidence interval [95%CI]: 59-76%) at a mean follow-up of 42.96 months. Conclusion The longer follow-up period was associated with a lower HP rate after CK radiosurgery for VS in the qualitative synthesis.

The endoscopic transcanal approach to the internal auditory canal: an anatomic study.

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

Retrosigmoid versus middle fossa approach for hearing and facial nerve preservation in vestibular schwannoma surgery: A systematic review and comparative meta-analysis.

BACKGROUND: Vestibular schwannomas (VS) are benign tumors arising from vestibular nerve's Schwann cells. Surgical resection via retrosigmoid (RS) or middle fossa (MF) is standard, but the optimal approach remains debated. This meta-analysis evaluated RS and MF approaches for VS management, emphasizing hearing preservation and Cranial nerve seven (CN VII) outcomes stratified by tumor size. METHODS: Systematic searches across PubMed, Cochrane, Web of Science, and Embase identified relevant studies. Hearing and CN VII outcomes were gauged using the American Academy of Otolaryngology-Head and Neck Surgery, Gardner Robertson, and House-Brackmann scores. RESULTS: Among 7228 patients, 56 % underwent RS and 44 % MF. For intracanalicular tumors, MF recorded 38 % hearing loss, compared to RS's 54 %. In small tumors (<1.5 cm), MF showed 41 % hearing loss, contrasting RS's lower 15 %. Medium-sized tumors (1.5 cm-2.9 cm) revealed 68 % hearing loss in MF and 55 % in RS. Large tumors (>3cm) were only reported in RS with a hearing loss rate of 62 %. CONCLUSION: Conclusively, while MF may be preferable for intracanalicular tumors, RS demonstrated superior hearing preservation for small to medium-sized tumors. This research underlines the significance of stratified outcomes by tumor size, guiding surgical decisions and enhancing patient outcomes.

Endoscopic third ventriculostomy in hydrocephalus secondary to vestibular schwannomas / Tercer ventriculostomía endoscópica en la hidrocefalia secundaria a schwanomas vestibulares

Introduction: Treatment options for hydrocephalus related to posterior fossa tumors have been extensively studied in the pediatric population, but the value of endoscopic third ventriculostomy in hydrocephalus secondary to vestibular schwannoma in adults, is controversial. A systematic search of the medical literature was carried out in Pubmed/Medline and SciElo for the identification and inclusion of articles, in addition to the preprint servers bioRxiv and medRxiv. The following descriptors were used: hydrocephalus and vestibular schwannomas or acoustic neuromas or acoustic neurinomas and endoscopic third ventriculostomy. The initial search found 195 articles. After selection, 5 articles were chosen for the study. Objective: To specify the role of the endoscopic third ventriculostomy in hydrocephalus secondary to vestibular schwannomas. Development: The articles included a total of 82 patients, in which an improvement of the symptoms was achieved in 86.6 percent of the cases. The decrease in ventricular diameter was reported in 82.9 percent of the cases and was only found explicit in 3 articles. Although the failure criteria used were varied, 2 of them predominated: the persistence of progressive symptomatic hydrocephalus and/or the need for shunt placement. Endoscopic third ventriculostomy failure only represented 14.6 percent. Conclusions: Third ventriculostomy is an acceptable technique with relative success for the treatment of symptomatic obstructive hydrocephalus secondary to vestibular schwannomas(AU)

Introducción: Las opciones de tratamiento para la hidrocefalia relacionada con tumores de fosa posterior han sido ampliamente estudiadas en la población pediátrica, pero es controvertido el valor de la tercer ventriculostomía endoscópica, en la hidrocefalia secundaria a schwanoma vestibular en adultos, previo a la resección del tumor. Se realizó una búsqueda sistemática de la literatura médica en Pubmed/Medline y SciElo para la identificación e inclusión de artículos, además de los servidores de preprint bioRxiv y medRxiv. Se utilizaron los siguientes descriptores: hydrocephalus y vestibular schwannomas o acoustic neuromas o acoustic neurinomas y endoscopic third ventriculostomy. La búsqueda inicial encontró 195 artículos. Después de la selección, se eligieron 5 artículos para el estudio. Objetivo: Especificar el papel de la tercer ventriculostomía endoscópica en la hidrocefalia secundaria a schwanomas vestibulares. Desarrollo: Los artículos incluyeron un total de 82 pacientes, en los que se logró una mejoría de los síntomas en el 86,6 por ciento de los casos. La disminución del diámetro ventricular se reportó en el 82,9 por ciento de los casos y solo se encontró explícita en 3 artículos. Aunque los criterios de fracaso utilizados fueron variados, predominaron dos de ellos: la persistencia de hidrocefalia sintomática progresiva o la necesidad de colocación de derivación. La falla de la tercer ventriculostomía endoscópica solo representó el 14,6 por ciento. Conclusiones: La tercera ventriculostomía endoscópica es una técnica aceptable y con relativo éxito para el tratamiento de la hidrocefalia obstructiva sintomática secundaria a schwanomas vestibulares(AU)

Middle Ear Cholesteatoma and Vestibular Schwannoma Resection Followed by Cochlear Implant: Surgical Challenges and Audiological Outcomes.

(1) Background: The occurrence of vestibular schwannoma (VS) associated with cholesteatoma is rare. A hearing impairment is one of the most significant issues in such cases. Moreover, the presence of middle and inner ear pathologies combined may represent a surgical challenge. No studies have described a combined surgical approach for these coexisting conditions (VS and cholesteatoma), nor the hearing rehabilitation outcomes of using cochlear implants for these patients. (2) Case Report: This paper is on a female patient who underwent simultaneous surgical treatments for VS and middle ear cholesteatoma in the right ear followed by a cochlear implant, describing the technique and the audiological results. (3) Conclusions: The surgical approach was successful and enabled the resection of lesions with the auditory nerve and cochlea preservation. Cochlear implantation in the right ear showed positive postoperative results, with an improvement in the results with the CI in silent and noisy environments.

Intracanalicular vestibular schwannomas: facial and hearing outcomes according to the location of the tumor in relation to the nerves of the internal auditory canal.

OBJECTIVE: The objective was to evaluate whether the position of the nerves within the internal auditory canal (IAC) has any effect on preoperative and postoperative cochlear and facial nerve function in patients with intracanalicular vestibular schwannoma (VS) resected through the retrosigmoid transmeatal approach. METHODS: Forty-four patients with sporadic intracanalicular VS, from a series of 710 patients with VS who underwent operations from January 1993 to April 2022, were retrospectively reviewed. The pattern of displacement of the cranial nerves and tumor within the IAC was recorded. Tumors were divided into 2 types: type T1A lesions had only anteriorly displaced nerves, and type T1B had posteriorly displaced vestibular nerves and anteriorly displaced facial and cochlear nerves. Differences in surgical outcomes between groups in terms of facial nerve function and hearing preservation were evaluated. RESULTS: Thirty-five cases (79.5%) were T1A tumors and 9 were T1B (20.5%). Gross-total resection and anatomical preservation of the facial and cochlear nerves were achieved in all patients. Postoperatively, all patients with T1A VS maintained normal facial nerve function; however, among T1B VS patients, 6 (67%) retained House-Brackmann grade I, 2 worsened to grade II, and 1 worsened to grade III at 6 months (p = 0.006). The 27 T1A VS patients with serviceable hearing maintained this status, and an additional patient with nonserviceable hearing improved to serviceable hearing; among T1B VS patients, only 2 of the 5 patients with serviceable hearing remained as such, 2 evolved to nonserviceable hearing, and 1 lost hearing after surgery (p = 0.0022). T1B VS patients had a 24-fold risk of facial nerve deterioration (relative risk [RR] 25.2, 95% CI 1.42-448.57, p = 0.028) and a 32-fold risk of hearing deterioration (RR 32.7, 95% CI 1.93-553, p = 0.016) after surgery. CONCLUSIONS: In intracanalicular VS, postoperative cochlear and facial nerve function are directly related to the location of the tumor in relation to the nerves, with worse outcomes in cases where the tumor is located between the vestibular and facial-cochlear nerves.

Brazilian Society of Otology task force - Vestibular Schwannoma ‒ evaluation and treatment.

OBJECTIVE: To review the literature on the diagnosis and treatment of vestibular schwannoma. METHODS: Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on vestibular schwannoma were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions. RESULTS: The topics were divided into 2 parts: (1) Diagnosis - audiologic, electrophysiologic tests, and imaging; (2) Treatment - wait and scan protocols, surgery, radiosurgery/radiotherapy, and systemic therapy. CONCLUSIONS: Decision making in VS treatment has become more challenging. MRI can diagnose increasingly smaller tumors, which has disastrous consequences for the patients and their families. It is important to develop an individualized approach for each case, which highly depends on the experience of each surgical team.

Tratamiento multimodal en los schwanomas vestibulares grandes / Multimodal Treatment for Large Vestibular Schwannomas

Introducción: Los schwanomas vestibulares son lesiones clasificadas como grado I por la Organización Mundial de la Salud. Las opciones conductuales incluyen la observación, la radiocirugía o la resección microquirúrgica endoscópica. Objetivo: Describir el rol del tratamiento multimodal en los schwanomas vestibulares. Métodos: Se realizó una búsqueda sistemática de literatura médica para la identificación e inclusión de artículos en las siguientes bases de datos: PubMed/Medline, SciELO y Google Scholar, además de los servidores de preprints BioRvix y MedRvix. Se usaron los siguientes descriptores: vestibular schwanoma OR acoustic neuroma AND nerve centered approach OR combined approach AND partial resection OR subtotal resection OR near total resection. Se excluyeron editoriales, cartas al editor, libros, revisiones, metaanálisis y aquellos artículos con método deficiente de más de 20 años de publicación o sin mención al tema de interés. Fueron incluidos 16 artículos. Desarrollo: Los artículos incluyeron un total de 699 pacientes, de los cuales solo 228 (32,6 porciento) recibieron radioterapia en el período posoperatorio. El período de seguimiento promedió 49,6 meses. La preservación de la función facial se logró en el 88,3 porciento de los casos y el control tumoral en el 80,7 porciento. El estado de la preservación auditiva solo fue informado en el 50 porciento de los estudios. El uso de la radioterapia adyuvante mostró gran variabilidad. Conclusiones: El tratamiento multimodal para los schwanomas vestibulares grandes -compuesto por la resección subtotal, vaciamiento intratumoral, seguido de radiocirugía- se ha convertido en una opción plausible. Se necesita la publicación de mayor cantidad de reportes para ofrecer recomendaciones y estratificar la conducta(AU)

Introduction: Vestibular schwannomas are lesions classified as grade I by the World Health Organization. Behavioral options include observation, radiosurgery or endoscopic microsurgical resection. Objective: To describe the role of multimodal treatment for vestibular schwannomas. Methods: A systematic search of medical literature, for the identification and inclusion of articles, was carried out in the databases PubMed/Medline, SciELO and Google Scholar, as well as in the preprint servers BioRvix and MedRvix. The following descriptors were used: vestibular schwannoma OR acoustic neuroma AND nerve centered approach OR combined approach AND partial resection OR subtotal resection OR near total resection. Editorials, letters to the editor, books, reviews and metaanalyses were excluded, as well as articles with deficient method of more than 20 years of publication or not mentioning the topic of interest. Sixteen articles were included. Development: The articles included a total of 699 patients, of which only 228 (32.6 ) received radiotherapy in the postoperative period. The average follow-up period was 49.6 months. Preservation of facial function was achieved in 88.3 percent of cases; and tumor control, in 80.7 percent. Hearing preservation status was reported in only 50 percent of the studies. The usage of adjuvant radiotherapy showed great variability. Conclusions: Multimodal treatment for large vestibular schwannomas -composed of subtotal resection and intratumoral draining, followed by radiosurgery- has become a plausible option. The publication of a greater amount of reports is necessary to provide recommendations and stratify the behavior(AU)

Factores radiológicos predictores de grado de resección en pacientes con schwannomas vestibulares / Radiological factors that predict the degree of resection and functional preservation in patients with vestibular schwannomas

Introducción: Existen diversos factores predictores de grado de resección en la cirugía de los schwannomas vestibulares (SV). Nuestro equipo en Tucumán realizó un estudio sistemático perioperatorio con un protocolo específico de resonancia magnética (RM) en estos pacientes. El objetivo del presente estudio fue determinar la utilidad de la RM como predictor de grado de resección de los SV. Materiales y métodos: Se realizó un estudio de serie, de tipo correlacional, descriptivo y retrospectivo de pacientes operados de SV, por nuestro equipo en Tucumán, entre enero 2014 y diciembre 2020 (n:92). Se realizó correlación estadística, entre las características imagenológicas con el grado de resección. Resultados: Un tumor sólido aumenta 39,19 veces la probabilidad de tener una resección completa en comparación con un tumor quístico. Conclusión: La RM permite definir adecuadamente la consistencia tumoral; un tumor sólido se asocia a una mayor probabilidad de resección total(AU)

Background: There are various predictors of degree of resection surgery for vestibular schwannomas (SV). Our team in Tucumán carried out a systematic perioperative study with a specific magnetic resonance imaging (MRI) protocol in these patients. The objective of the present study was to determine the usefulness of MRI as a predictor of the degree of resection of VS. Methods: A serial, correlational, descriptive, and retrospective study of patients operated on for SV was carried out by our team in Tucumán, between January 2014 and December 2020 (n: 92). Statistical correlation was made between the imaging characteristics with the degree of resection. Results: A solid tumor increases 39.19 times the probability of having a complete resection compared to a cystic tumor. Conclusion: MRI allows to adequately define tumor consistency; a solid tumor is associated with a higher probability of total resection(AU)

Surgical salvage for recurrent vestibular schwannoma after primary stereotactic radiosurgery.

Background: The management of vestibular schwannoma has evolved over the past hundred years. In the last decades, surgery has been gradually replaced by radiation therapy as a primary treatment modality, particularly for small tumors, due to the less invasive nature and the compared reported outcomes in tumor control and hearing preservation. However, irradiation sometimes fails to stop tumor growth. In a long-term follow-up after primary fractionated stereotactic radiotherapy, the rate of treatment failure was reported as 3% and needed surgical salvage. For single-fraction modality, Hasegawa et al. reported salvage treatment after primary Gamma Knife radiosurgery in 8%, where 90% of these underwent surgery and 50% of those who were treated with a second gamma knife surgery required surgical intervention later. An increase in tumor volume by more than 10-20%, tumor growth after three years, and no return to pretreatment volume after transient swelling have been considered as tumor recurrence rather than pseudoprogression, a transient increase in tumor volume after radiotherapy that occurs up to 30% of cases. It has been reported that microsurgery after radiotherapy is more difficult, with most authors reporting a loss of defined arachnoid planes and worse cranial nerve outcomes, especially for hearing and facial nerve function. Case Description: A 43-year-old female patient was incidentally (asymptomatic) diagnosed on a magnetic resonance imaging (MRI) scan harboring a left vestibular schwannoma, grade T2 (Hannover classification), in 2015. Neurologic examination was unremarkable, and audiometry testing was normal. She was initially treated with observation. Three years later, in 2018, the lesion had enlarged, becoming a grade T3a and reaching the cistern of the cerebellopontine angle. The tumor was then treated with fractionated stereotactic radiosurgery (5 sessions of 5 Gy). MRI scans in 2019 and 2020 showed slight tumor growth. This enlargement was attributed to a pseudoprogression after radiosurgery, and only observation was advocated. In 2022, 4 years later, after radiosurgery, the tumor was still growing, and the patient began to suffer from hearing loss. A failure treatment was considered, and microsurgery was indicated. The patient was counseled about the risk of functional nerve impairment, and surgical consent was obtained. A retro sigmoid approach was planned. A gross total resection was attempted due to the clear subperineural plane during tumor dissection and because it was the only option that would provide a cure for the patient. The adjacent neurovascular structures were firmly adhered to the tumor capsule, which represented a major challenge for microdissection. The tumor was soft, without significant bleeding. A total resection was achieved, and the facial nerve was anatomically preserved. The patient developed facial paresis (House-Brackmann III) in the immediate postoperative period, which improved at the 6-month follow-up. Hearing loss did not improve. Postoperative MRI showed total resection. Conclusion: Microsurgery after radiotherapy for vestibular schwannoma is challenging in terms of indication, when to indicate, resection target, difficulty in dissection due to local changes, and outcome. Gross total resection may be considered, as it is the only treatment that may provide a cure for the patient. However, the patient should be counseled about the risks.

Brazilian Society of Otology task force - Vestibular Schwannoma - evaluation and treatment

Abstract Objective: To review the literature on the diagnosis and treatment of vestibular schwannoma. Methods: Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on vestibular schwannoma were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions. Results: The topics were divided into 2 parts: (1) Diagnosis - audiologic, electrophysiologic tests, and imaging; (2) Treatment - wait and scan protocols, surgery, radiosurgery/radiotherapy, and systemic therapy. Conclusions: Decision making in VS treatment has become more challenging. MRI can diagnose increasingly smaller tumors, which has disastrous consequences for the patients and their families. It is important to develop an individualized approach for each case, which highly depends on the experience of each surgical team.

Dissociation between Caloric and Video Head Impulse Tests in Dizziness Clinics.

Vestibular assessment tests such as the video head impulse test (vHIT) for the horizontal semicircular canal, and caloric test (Cal), both evaluate horizontal canal function. One would assume that the outcomes for these tests should lead to concordant results, yet several studies have suggested that dissociation can occur in certain pathological conditions. As this topic remains inconclusive, this review aims to analyze the scientific evidence regarding the patterns of hypofunction observed in vHIT and Cal in different otoneurological diseases. A comprehensive review of the literature regarding dissociation between these tests in common neurotological diseases was carried out. Articles were analyzed when data for vHIT and Cal were described in a way that it was possible to calculate discordance rates; both retrospective and prospective studies were analyzed. In this review, the discordance rates were as follows: 56% in Ménière's disease, 51.5% in vestibular migraine, 37.2% in vestibular schwannoma, and 20.8% in vestibular neuritis. These results highlight the benefit of using both Cal and vHIT, and that they are complementary tests.

Relationship between Signal Intensity of the Labyrinth and Cochleovestibular Testing and Morphologic Features of Vestibular Schwannoma.

Objectives The aim of this article was to evaluate the relationship between signal intensity of the labyrinth and vestibulocochlear function and morphologic features of vestibular schwannoma (VS). Design Cross-sectional Study. Setting Tertiary referral center. Participants Fifty-four patients with sporadic, untreated VS. Main Outcome Measure Signal intensity of the cochlea and vestibule (SIRc and SIRv: signal intensity of cochlea/vestibule compared with cerebellar signal intensity; AURc and AURv: SIRc/SIRv of the affected side compared with the unaffected side) in 1.5T T2-weighted images was correlated with size (Hannover classification), cystic status, distance from the fundus of the internal auditory canal, video head impulse test (vHIT), and audiometry. Results Signal intensity of the vestibule was higher than that of the cochlea ( p < 0.01). Large tumors had lower SIRc than smaller tumors ( p = 0.03); Hannover T1 tumors had higher SIRc ( p < 0.01), SIRv ( p < 0.01), AURc ( p < 0.01) and AURv ( p < 0.01) than the rest; heterogenous and cystic tumors had higher SIRv than solid large tumors ( p = 0.02); superior vestibular nerve pattern on vHIT had higher SIRv and AURv than inferior vestibular nerve and mixed patterns ( p = 0.03 and 0.004, respectively); and there was a weak correlation between AURv and speech discrimination ( r = 0.33, p = 0.04). Conclusion A more abnormal signal intensity of the labyrinth is associated with larger size and solid status of VS. There was a positive relationship between signal intensity of the labyrinth and speech discrimination scores on audiogram.

Microsurgical Resection of Intracanalicular Vestibular Schwannoma via Retrosigmoid Approach: 3-Dimensional Operative Video.

Vestibular schwannomas are a multifaceted group of tumors that can present with different sizes and involvement of critical neurovascular structures.1-6 While operating on these tumors, a critical goal is postoperative preservation of facial nerve function and hearing. We present the case of a 66-year-old male with a history of severe left-sided tinnitus and progressive hearing loss (Video 1). Preoperative imaging depicted a lesion highly suggestive of an intracanalicular vestibular schwannoma. Due to worsening of symptoms and after thoughtful discussion with the patient, microsurgical resection was indicated under constant neurophysiologic monitoring. A retrosigmoid approach was employed, and the posterior wall of the internal auditory canal was opened, allowing exposure of tumor and its total resection. Postoperative imaging demonstrated complete tumor resection. The patient's symptoms improve, and there were no new neurologic deficits on follow-up. Anatomical images were a Courtesy of the Rhoton Collection, American Association of Neurological Surgeons (AANS)/Neurosurgical Research and Education Foundation (NREF).

Hipoacusia sensorineural asimétrica en el diagnóstico de schwannoma vestibular / Asymmetric sensorineural hearing loss in the diagnosis of vestibular schwannoma

Introducción: se ha descrito que los pacientes con hipoacusia asimétrica cursan en un 2% con lesiones retrococleares. La conducta de escrutinio se ha basado en la audiometría. Existen varias definiciones de asimetría audiométrica descritas en la literatura, pero sin llegar a un consenso. Aunque la prueba de oro para el diagnóstico de schwannoma vestibular es la resonancia magnética con gadolíneo, la sospecha clínica se hace en base a la asimetría audiométrica. Objetivo: hacemos una revisión de los trabajos publicados al respecto en la literatu-ra y comentamos nuestra experiencia. Reflexión: queremos enfatizar en la importancia de estudiar a los pacientes con hipoacusia asimétrica con el fin de descartar patología retrococlear. Conclusión: a pesar de que no existe un consenso claro en la definición de hi-poacusia asimétrica, la sospecha clínica de un schwannoma vestibular se basa en la audiometría

Background: It is described that 2% of patients with asymmetric hearing loss have retrocochlear lesions. The scrutiny behavior has been based on audiometry. There are several definitions of audiometric asymmetry described in the literature, but without reaching a consensus. Although the gold standard for the diagnosis of vestibular schwannoma is gadolinium magnetic resonance imaging, the clinical sus-picion is based on audiometric asymmetry. Objective: we review the results published in this regard in the literature and com-ment on our own experience. Reflection: we want to emphasize the importance of studying asymmetric hearing loss patients in order to rule out retrocochlear etiology. Conclusions: although there is no clear consensus on the definition of asym-metric hearing loss, the clinical suspicion of a vestibular schwannoma is based on the audiometry.

Pilocytic Astrocytoma of the Cerebellopontine Angle with cerebrospinal fluid Spread in an Adult: A Case Report / Astrocitoma pilocítico no ângulo pontocerebelar com disseminação liquórica em paciente adulto: Relato de caso

Introduction Pilocytic astrocytoma of the cerebellopontine angle (CPA) is uncommon, and its spread to the cerebrospinal fluid (CSF) at the time of diagnosis has not been reported in the literature. Case Presentation We report the case of a 33-year-old man with multifocal pilocytic astrocytoma diagnosed by magnetic resonance imaging (MRI) and confirmed by histopathological examination, and present the radiological and histopathological findings. Conclusion In the case herein reported, we observed spread of the pilocytic astrocytoma of the CPA to the CSF at the initial diagnosis, and early detection by MRI is very important regarding the treatment modality and prognosis.

Introdução O astrocitoma pilocítico no ângulo pontocerebelar (APC) é incomum, e sua disseminação liquórica no momento do diagnóstico não foi relatada na literatura. Apresentação do Caso Relatamos o caso de um homem de 33 anos com astrocitoma pilocítico multifocal diagnosticado por ressonância magnética (RM) e confirmado por exame histopatológico, e apresentamos os achados radiológicos e histopatológicos. Conclusão No caso relatado, observou-se disseminação liquórica de astrocitoma pilocítico no APC no diagnóstico inicial, e a detecção precoce por RM é muito importante para a modalidade de tratamento e o prognóstico.

Endoscopic resection through a retrosigmoid transmeatal approach of a large-sized vestibular schwannoma: operative video and technical nuances.

Surgical management of vestibular schwannomas has improved over the last 30 years. Whereas in the past the primary goal was to preserve the patient's life, today neurological function safeguarding is the main objective, with numerous strategies involving single resection, staged resections, postoperative radiosurgery, or single radiosurgery. The retrosigmoid approach remains the primary pathway for surgical access to the cerebellopontine angle (CPA). The use of an endoscope has great advantages. It contributes to the visualization and resection of residual tumor and also reduces the need for cerebellar retraction. The authors present a fully endoscopic resection of a large-sized vestibular schwannoma with facial nerve preservation. The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID21106.

Primera Radiocirugía de schwannoma vestibular en el sistema público uruguayo, Hospital Regional de Tacuarembó. Centro Oncológico del Norte

Resumen: Los schwannomas vestibulares son tumores benignos de lento crecimiento. Aproximadamente el 90% son de presentación unilateral, el 10% restante, son bilaterales y se encuentran asociados al síndrome de Neurofibromatosis tipo 2. Las opciones de tratamiento son observación, cirugía o radiocirugía. La radiocirugía es un tratamiento seguro, con altas tasas de control local y baja morbilidad en schwannomas vestibulares menores a 3 cm de diámetro mayor. Reportamos la primera radiocirugía realizada en el sistema público uruguayo para este tipo de patologías.

Abstract: Vestibular schwannomas are slow-growing benign tumors. Approximately 90% are unilateral, the remaining 10% are bilateral and are associated with Neurofibromatosis type 2 syndrome. Treatment options are observation, surgery or radiosurgery. Radiosurgery is a safe treatment, with high local control rates and low morbidity in vestibular schwannomas smaller than 3 cm in major diameter. We report the first radiosurgery performed in the Uruguayan public system for this type of pathology.

Resumo: Os schwannomas vestibulares são tumores benignos de crescimento lento. Aproximadamente 90% são unilaterais, os restantes 10% são bilaterais e estão associados à síndrome de neurofibromatose tipo 2. As opções de tratamento são observação, cirurgia ou radiocirurgia. A radiocirurgia é um tratamento seguro, com altas taxas de controle local e baixa morbilidade em schwannomas vestibulares com menos de 3 cm de diâmetro maior. Relatamos a primeira radiocirurgia realizada no sistema público uruguaio pra este tipo de patologia.

Vestibular schwannoma: predictive factors of long-term postoperative neurological outcome.

Introduction: Vestibular schwannoma (VS) is a slow-growing, benign tumor that is usually diagnosed when symptoms develop. Surgical management aims to reduce long-term sequelae (LTS) associated with late diagnosis.Objective: Identify predictive factors of LTS after VS surgery and clinical outcome measured by modified Rankin scale (mRS).Methods: This cohort study included patients submitted to VS surgery from 1999 to 2014, with a mean follow-up of 6.4 ± 4.5 years. Disability was assessed across the mRS the primary outcome was defined by scores 3 to 6, which implied poor outcome in neurological recovery. Predictive factors were identified through multivariate logistic regression.Results: A total of 101 patients were included in this study. Fifty-one (50.49%) presented mRS ≥ 3 on the late postoperative period. Men comprise 22.8%, and the mean age was 47.1 ± 16.0 years (range19-80). Patients with mRS ≥ 3 presented larger tumors (3.7 ± 1.1 cm vs. 3.2 ± 1.0 cm, p < .001), less total resection (50% vs. 76.7%, p < .010) and more neurofibromatosis II(NFII) (84.9% vs. 64.3%, p = .023). On multivariate analysis NFII, tumor size and type resection were predictive of degree of autonomy (mRS ≥3: NF II (OR 3.5, 95% CI 1.08-11.36, p = .036) and tumor size (each 1 cm, OR1.51, 95% CI 0.96-2.38, p = .050).Conclusion: Tumor size, presence of NFT II, type of surgical approach and number of surgeries were identified as predictive factors of functional sequelae in long-term follow-up after VS surgery.HighlightsOne-third of our patients presented some degree of disability that impact in autonomy (mRS ≥ 3) in the late postoperative period.Tumor size, NFII, surgical approach were predictive to comprise independency.Considering the cranial nerve monitoring and late diagnosis, our results can give some contribution to understanding the Brazilian profile of VS surgery.Our findings suggests the need to look over what it is well recognized and identify aspects that affect the prognosis such as functional disabilities in VS surgery.