Electroencephalographic microstates in vestibular schwannoma patients with tinnitus / 南方医科大学学报

OBJECTIVE@#To explore the biomarkers of tinnitus in vestibular schwannoma patients using electroencephalographic (EEG) microstate technology.@*METHODS@#The EEG and clinical data of 41 patients with vestibular schwannoma were collected. All the patients were evaluated by SAS, SDS, THI and VAS scales. The EEG acquisition time was 10-15 min, and the EEG data were preprocessed and analyzed using MATLAB and EEGLAB software package.@*RESULTS@#Of the 41 patients with vestibular schwannoma, 29 patients had tinnitus and 12 did not have tinnitus, and their clinical parameters were comparable. The average global explanation variances of the non-tinnitus and tinnitus groups were 78.8% and 80.1%, respectively. The results of EEG microstate analysis showed that compared with those without tinnitus, the patients with tinnitus had an increased frequency (P=0.033) and contribution (P=0.028) of microstate C. Correlation analysis showed that THI scale scores of the patients were negatively correlated with the duration of microstate A (R=-0.435, P=0.018) and positively with the frequencies of microstate B (R=0.456, P=0.013) and microstate C (R=0.412, P=0.026). Syntax analysis showed that the probability of transition from microstate C to microstate B increased significantly in vestibular schwannoma patients with tinnitus (P=0.031).@*CONCLUSION@#EEG microstate features differ significantly between vestibular schwannoma patients with and without tinnitus. This abnormality in patients with tinnitus may reflect the potential abnormality in the allocation of neural resources and the transition of brain functional activity.

Preliminary application of combined auditory monitoring technique in resection of vestibular neurinoma / 中华耳鼻咽喉头颈外科杂志

Objective: To explore the value of electrically evoked auditory brainstem response (EABR) monitoring combined with brainstem auditory evoked potential (BAEP) and compound action potential (CAP) monitoring during vestibular schwannoma resection for the protection of the cochlear nerve. Methods: Clinical data from 12 patients with vestibular schwannomas who had useful hearing prior to surgery were analyzed at the PLA General Hospital from January to December 2021. Among them, there were 7 males and 5 females, ranging in age from 25 to 59 years. Before surgery, patients underwent audiology assessments (including pure tone audiometry, speech recognition rate, etc.), facial nerve function evaluation, and cranial MRI. They then underwent vestibular schwannoma resection via the retrosigmoid approach. EABR, BAEP, and CAP were simultaneously monitored during surgery, and patients' hearing preservation was observed and analyzed after surgery. Results: Prior to surgery, the average PTA threshold of the 12 patients ranged from11 to 49 dBHL, with a SDS of 80% to 100%. Six patients had grade A hearing, and six patients had grade B hearing. All 12 patients had House-Brackman grade I facial nerve function prior to surgery. The MRI indicated tumor diameters between 1.1 and 2.4 cm. Complete removal was achieved in 10/12 patients, while near-total removal was achieved in 2/12 patients. There were no serious complications at the one-month follow-up after surgery. At the three-month follow-up, all 12 patients had House-Brackman grade I or II facial nerve function. Under EABR with CAP and BAEP monitoring, successful preservation of the cochlear nerve was achieved in six of ten patients (2 with grade B hearing, 3 with grade C hearing, and 1 with grade D hearing). Successful preservation of the cochlear nerve was not achieved in another four patients (all with grade D hearing). In two patients, EABR monitoring was unsuccessful due to interference signals; however, Grade C or higher hearing was successfully preserved under BAEP and CAP monitoring. Conclusion: The application of EABR monitoring combined with BAEP and CAP monitoring during vestibular schwannoma resection can help improve postoperative preservation of the cochlear nerve and hearing.

Application of cochlear nerve action potential monitoring in the resection of vestibular schwannomas / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate the application of cochlear nerve action potential (CNAP) monitoring in the resection of vestibular schwannoma, especially evaluating its significance for hearing preservation. Methods: From April 2018 to December 2021, 54 patients with vestibular schwannoma who underwent resection via retrosigmoid approach were collected in Chinese PLA General Hospital. Before surgery, all patients had effective hearing (AAO-HNS grade C or above). Brainstem auditory evoked potential (BAEP) combined with CNAP monitoring was performed during surgery. The CNAP monitoring was combined with continuous monitoring and cochlear nerve mapping. And patients were divided into hearing preservation group and non-preserved group according to postoperative AAO-HNS grade. SPSS 23.0 software was used to analyze the differences of CNAP and BEAP parameters between the two groups. Results: A total of 54 patients completed intraoperative monitoring and data collection, including 25 males (46.3%) and 29 females (53.7%), aged 27-71 years with an average age of 46.2 years. The maximum tumor diameter were (18.1±5.9) mm (range 10-34 mm). All tumors were totally removed with preserved facial nerve function (House-Brackmann grade I-II). The hearing preservation rate of 54 patients was 51.9% (28/54). During surgery, the V wave extraction rate of BAEP waveform was 85.2% (46/54) before tumor resection, 71.4% (20/28) in the hearing preservation group after tumor resection, and disappeared in the hearing preservation group (0/26). CNAP waveform was elicited in 54 patients during operation. Differences were found in the distribution of CNAP waveforms after tumor resection. The waveforms of the hearing-preserving group were triphasic and biphasic, while those in the non-preserving group were low-level and positive. For hearing preservation group, the amplitude of N1 wave after tumor resection was significantly higher than that before tumor resection[14.45(7.54, 33.85)μV vs 9.13(4.88, 23.35)μV, P=0.022]; However, for the non-preserved group, the amplitude of N1 wave after tumor resection was significantly lower than that before tumor resection [3.07(1.96, 4.60)μV vs 6.55(4.54, 9.71)μV, P=0.007]; After tumor resection, the amplitude was significantly higher than that of the unreserved group [14.45(7.54, 33.85)μV vs 3.07(1.96, 4.60)μV, P<0.001]. Conclusions: BAEP combined with CNAP monitoring is conducive to intraoperative hearing protection, and the application of cochlear nerve mapping can prompt the surgeon to avoid nerve injury. The waveform and N1 amplitude of CNAP after tumor resection have a certain value in predicting postoperative hearing preservation status.

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.

A minimally invasive endoscope assisted retrosigmoid approach for removal of arachnoid cysts in the internal auditory canal: a step by step description / Abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção de cistos aracnóides no conduto auditivo interno: descrição passo a passo

Abstract Introduction: Arachnoid cyst in the internal auditory canal is a quite rare pathology but due to its compressive action on the nerves in this district should be surgically removed. Several surgical techniques have been proposed but no surgeons have used the minimally assisted endoscope retrosigmoid approach for its removal. Objective: To investigate the feasibility of using a minimally invasive endoscope assisted retro-sigmoid approach for surgical removal of arachnoid cysts in the internal auditory canal. Methods: Minimally invasive endoscope assisted retrosigmoid approach allows to access to the internal auditory canal through a minimally invasive retrosigmoid approach that combines the use of a microscope and an endoscope. It is performed in six steps: soft tissue step, bone step, dura step, cerebellopontine angle step (performed using an endoscope and a microscope), microscope-endoscope assisted arachnoid cysts removal and closure. We tested minimally invasive endoscope assisted retrosigmoid approach for removal of arachnoid cysts in the internal auditory canal on two human cadaveric heads (specimens) of subjects affected from audio-vestibular disorders and with arachnoid cysts in the internal auditory canal confirmed by magnetic resonance imaging. Results: The mass was completely and successfully removed from the two specimens with no damage to the nerves and/or vessels in the surgical area. Conclusion: The results of our study are encouraging and support the feasibility of using minimally invasive endoscope assisted retrosigmoid approach for removal of arachnoid cysts in the internal auditory canal. While further clinical in-vivo studies are needed to confirm the accuracy and safety of using the minimally invasive endoscope assisted retrosigmoid approach for this specific surgery, our group has successfully used the minimally invasive endoscope assisted retrosigmoid approach in the treatment of microvascular compressive syndrome, schwannoma removal and vestibular nerve resection.

Resumo Introdução: O cisto aracnóide no conduto auditivo interno é uma doença bastante rara, mas, devido à sua ação compressiva sobre os nervos deste local, ele deve ser removido cirurgicamente. Várias técnicas cirúrgicas foram propostas, mas ninguém utilizou a abordagem retrosigmoide minimamente invasiva assistida por endoscopia para a sua remoção. Objetivo: Investigar a viabilidade do uso da abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção cirúrgica de cistos aracnóides no conduto auditivo interno. Método: A abordagem retrosigmoide minimamente invasiva assistida por endoscopia permite o acesso ao conduto auditivo interno através de uma abordagem retrosigmóide minimamente invasiva que combina o uso de um microscópio e um endoscópio. É realizada em seis etapas: do tecido mole, óssea, dura-máter, do ângulo pontocerebelar (realizado com um endoscópio e um microscópio), remoção e fechamento assistidos por endoscópio-microscópico. Testamos a abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção de cistos aracnóides no conduto auditivo interno em duas cabeças de cadáveres humanos (espécimes) de indivíduos afetados por distúrbios auditivos-vestibulares e com cistos aracnóides no conduto auditivo interno confirmado por imagem de ressonância magnética. Resultados: A lesão foi removida completamente e com sucesso nos dois espécimes sem dano aos nervos e/ou vasos na área cirúrgica. Conclusão: Os resultados do nosso estudo são encorajadores e apoiam a viabilidade do uso da abordagem retrosigmoide minimamente invasiva assistida por endoscopia para remoção de cistos aracnóides no conduto auditivo interno. Embora mais estudos clínicos in vivo sejam necessários para confirmar a precisão e a segurança do uso da abordagem retrosigmoide minimamente invasiva assistida por endoscopia para essa cirurgia específica, nosso grupo utilizou com sucesso a abordagem retrosigmoide minimamente invasiva assistida por endoscopia no tratamento da síndrome compressiva microvascular, remoção de schwannoma e ressecção do nervo vestibular.

Neurofibromatosis tipos 1 y 2 / Neurofibromatosis type 1 and 2

La neurofibromatosis (NF) comprende un grupo de enfermedades genéticas de herencia autosómica dominante, que se clasifican de la siguiente manera: neurofibromatosis tipo 1 (NF1), neurofibromatosis tipo 2 (NF2) y schwannomatosis (también conocida como neurofibromatosis tipo 3). Esta última es una enfermedad muy infrecuente, con una prevalencia aproximada de 1/126 000 personas, por lo que solo profundizaremos las dos primeras. La NF1, también conocida como la enfermedad de Von Recklinghausen, es la más frecuente de las tres y afecta principalmente la piel y el sistema nervioso periférico. Se caracteriza por la presencia de máculas "café con leche", pecas axilares o inguinales, nódulos de Lisch (hamartomas en el iris) y neurofibromas (tumores de la vaina de nervios periféricos). Otras manifestaciones menos frecuentes, aunque de mayor gravedad, incluyen gliomas del nervio óptico, meningiomas, neurofibromas malignos, escoliosis y displasia de la tibia. Su diagnóstico se suele realizar al nacimiento o durante los primeros años de vida, y se estima que un 50% de quienes la padecen presenta dificultades cognitivas. No hay datos concluyentes sobre la mortalidad en los pacientes con NF1, aunque se sabe que la expectativa de vida es menor que en la población general. La NF2 tiene una prevalencia considerablemente menor que la NF1 y su inicio es más tardío, afectando principalmente a adultos jóvenes. La presentación clínica típica se caracteriza por acúfenos, hipoacusia y ataxia en contexto de la presencia de schwannomas vestibulares bilaterales. Otros hallazgos menos frecuentes incluyen schwannomas de nervios periféricos, meningiomas, ependimomas o astrocitomas. La esperanza de vida es de unos 36 años, con una supervivencia media desde el momento del diagnóstico de 15 años. (AU)

Neurofibromatosis (NF) includes a group of genetic diseases with an autosomal-dominant inheritance pattern, and they are classified as follows: Neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2) and Schwannomatosis (also known as neurofibromatosis type 3). This last one is a very rare disease, with an approximate prevalence of 1/126000, so we will only deepen in the first two. NF1, also known as von Recklinghausen disease, is the most frequent, and mainly affects the skin and peripheral nervous system. Its typical manifestations are the presence of café-au-lait macules, axillary or inguinal freckles, Lisch nodules (hamartomas in the iris) and neurofibromas (peripheral nerve sheath tumors). Less frequent manifestations, although more serious, include optic nerve gliomas, meningiomas, malignant neurofibromas, scoliosis and tibial dysplasia. The diagnosis is usually made at birth or during the first years of life, and approximately 50% of patients present cognitive difficulties. There is no conclusive data on mortality in patients with NF1, although it is known that life expectancy is lower than in general population. NF2 has a considerably lower prevalence than NF1, and its onset is later in life, mainly affecting young adults. Its typical clinical presentation is characterized by tinnitus, hearing loss and ataxia in the context in the presence of bilateral vestibular schwannomas. Less frequent findings include peripheral nerve schwannomas, meningiomas, ependymomas or astrocytomas. Life expectancy is about 36 years old, with a median survival from the moment of diagnosis of 15 years. (AU)

Resección microquirúrgica de schwannoma vestibular grado IVa con preservación de la función facial / Microsurgical resection of vestibular schwannoma grade IVa with preservation of facial function

Introducción: La cirugía de los schwannoma vestibulares constituye un desafío para los neurocirujanos. Debido a que se trata de un tumor benigno la resección completa de la lesión implica la curación del paciente. Sin embargo, este objetivo no siempre es fácil de lograr preservando la función de los nervios facial y acústico, especialmente en tumores de gran tamaño. Objetivos: Presentar detalles técnicos de la cirugía de resección de un schwannoma vestibular de gran tamaño (IVa) en el que se pudo preservar la función facial. Materiales y métodos: Se presenta el caso de una paciente femenina de 36 años que consultó por hipoacusia izquierda. En la RM preoperatoria se evidenciaba una lesión ocupante de espacio del ángulo pontocerebeloso izquierdo compatible con schwannoma vestibular con compresión del tronco encefálico y sin efecto de masa sobre el IV ventrículo (grado IVa). Mediante un abordaje suboccipital retromastoideo en posición de decúbito lateral se realizó la resección de la lesión en forma completa asistida por monitoreo del nervio facial. En todo momento se pudo preservar el plano aracnoideo que separaba el tumor de los nervios adyacentes. Resultados: Se logró una resección macroscópicamente completa con preservación de la función del nervio facial. La paciente permaneció internada por 96 hs en el postoperatorio sin complicaciones derivadas del procedimiento. Conclusión: La preservación del plano aracnoideo es un detalle técnico de mucha importancia para disminuir las posibilidades de lesión de los nervios facial y auditivo en la cirugía de resección de los schwannoma vestibulares.

Introduction: The surgery of vestibular schwannomas is a challenge for neurosurgeons.Because it is a benign tumor, complete resection of the lesion involves healing the patient. However, this objective is not always easy to achieve, preserving the function of both the facial and acoustic nerves, especially when dealing with large tumors. Objective: The objective of the video is to present some technical details of a large vestibular schwannoma (IVa) surgery in which the facial function could be preserved. Materials and methods: We present the case of a 36-year-old female patient who consulted for left hearing loss. The preoperative MRI showed a space- occupying lesion of the left pontocerebellar angle, which was compatible with vestibular schwannoma, with compression of the brainstem but with no mass effect on the IV ventricle (grade IVa). By means of a retromastoid suboccipital approach in the lateral prone position, the lesion was completely resected assisted by neurophysiological monitoring of the facial nerve. At all times, the arachnoid plane separating the tumor from the adjacent nerves was preserved. Results: A macroscopically complete resection was achieved preserving the facial nerve function. The patient stayed hospitalized for 96 hours during the postoperative period without any complication from the procedure. Conclusion: Preserving the arachnoid plane is a very important technical detail to reduce the possibilities of injury of the facial and auditory nerves in the vestibular schwannoma resection surgery.

Trigeminal Neuralgia Caused by Cerebellopontine Angle Tumors: Surgical Series

Introduction Cerebellopontine angle (CPA) tumors represent an important cause of persistent and refractory trigeminal neuralgia (TN). It is believed that between 1 and 9.9% of the cases of patients presenting with TN painful manifestation are caused by space-occupying lesions. Objective The objective of the present study is to describe the clinical and surgical experience of the operative management of patients presenting with secondary type TN associated with CPA tumors. Method An observational investigation was conducted with data collection from patients with secondary type TN associated with CPA tumors who were treated with surgical resection of the space-occupying lesion and decompression of the trigeminal nerve from January 2013 to November 2016 in 2 different centers in the western region of the state of São Paulo, Brazil. Results We operated on 11 consecutive cases in which TN was associated with CPA during the period of analysis. Seven (63.6%) patients were female, and 4 (36.4%) were male. Seven (63.6%) patients presented with right-side symptoms, and 4 (36.4%) presented with left-side symptoms. After 2 years of follow-up, we observed that 8 (72.7%) patients showed a complete improvement of the symptoms, with an excellent outcome, and that 3 (27.3%) patients showed an incomplete improvement, with a good outcome. No patient reported partial improvement or poor outcome after the follow-up. There was no operative mortality. Conclusion Cerebellopontine angle tumors represent an important cause of TNandmust be included in the differential diagnosis of patients presenting with refractory and persistent symptoms. Surgical treatment with total resection of the expansive lesion and effective decompression of the trigeminal nerve are essential steps to control the symptoms.

Different clinical presentation of intralabyrinthine schwannomas - a systematic review / Diferentes apresentações clínicas do schwannoma intralabiríntico --- uma revisão sistemática

Abstract Introduction: Intralabyrinthine schwannoma is a rare, benign tumor that affects the most terminal portions of the vestibular and cochlear nerves. This tumor can be classified into 10 subtypes, according to its inner ear location. Objective: To carry out a comprehensive review of the most frequent auditory manifestations secondary to the intralabyrinthine schwannoma, describing the possible underlying pathophysiological mechanisms. Methods: Systematic review of the literature until October 2017 using the PubMed, Web of Science and Scopus databases. The inclusion criteria were clinical manifestations of the intralabyrinthine schwannoma. Three researchers independently assessed the articles and extracted relevant information. The description of a case of an intravestibular subtype intralabyrinthine schwannoma with multiple forms of clinical presentations was used as an example. Results: Twenty-seven studies met our inclusion criteria. The most common intralabyrinthine schwannoma subtype was the intracochlear, followed by the intravestibular type. All the cases demonstrated hearing loss, usually progressive hearing loss. Conclusion: The diagnosis of intralabyrinthine schwannomas is based on high-resolution magnetic resonance imaging and should be included in the differential diagnosis of patients with vestibulocochlear complaints. Although there are approximately 600 cases in the literature, we still lack a detailed description of the clinical evolution of the patients, correlating it with MRI findings of temporal bones and tumor subtype.

Resumo Introdução: Schwannoma intralabiríntico é um tumor benigno, raro, que afeta as porções mais terminais dos nervos vestibular e coclear. Este tumor pode ser classificado, de acordo com sua localização na orelha interna, em 10 subtipos. Objetivo: Realizar uma revisão abrangente das manifestações auditivas mais frequentes secundárias ao schwannoma intralabiríntico e descrever os possíveis mecanismos fisiopatológicos subjacentes. Método: Revisão sistemática da literatura até outubro de 2017 nas bases de dados PubMed, Web of Science e Scopus. O critério de inclusão foi manifestações clínicas do schwannoma intralabiríntico. Três pesquisadores avaliaram de forma independente os artigos e extraíram informações relevantes. Exemplificamos com a descrição de um caso de schwannoma intralabiríntico subtipo intravestibular com múltiplas formas de apresentações clínicas. Resultados: Vinte sete estudos contemplaram nossos critérios de inclusão. O subtipo do schwannoma intralabiríntico mais comum encontrado foi o intracoclear, seguido pelo intravestibular. Todos os casos apresentaram alteração auditiva, normalmente perda auditiva progressiva. Conclusão: O diagnóstico de schwannomas intralabirínticos baseia-se em exames de ressonância magnética de alta resolução e deve ser incluído no diagnóstico diferencial de pacientes com queixas vestibulococleares. Apesar de termos aproximadamente 600 casos na literatura, ainda nos falta descrição detalhada da evolução clínica dos pacientes em correlação com achados na ressonância magnética de ossos temporais e o subtipo tumoral.

Abordaje translaberíntico y rehabilitación vestibular: eficacia en el tratamiento de la disfunción vestibular en pacientes con schwannoma vestibular / Translabyrinthine approach and vestibular rehabilitation: efficacy in the treatment of vestibular dysfunction in patients with vestibular schwannoma

Introducción: En los schwannomas vestibulares (SV), la incidencia de disfunción vestibular como principal síntoma es del 10%, sin embargo, producen un notorio impacto en la calidad de vida de los pacientes. Objetivo: Evaluar el impacto funcional que produce la exéresis de SV por via translaberintica y la rehabilitación vestibular sobre los síntomas vestibulares, en los pacientes tratados en nuestro hospital. Material y Métodos: Se realizó un análisis prospectivo de 2 pacientes con diagnóstico de SV y disfunción vestibular agregada. En ambos pacientes, se realizó la resección a través de un abordaje translaberíntico. Los pacientes fueron evaluados funcionalmente antes y después de la cirugía. El impacto de la misma sobre la calidad de vida se evalúo mediante la Escala de Discapacidad por Mareo (DHI). Todos los pacientes realizaron un plan de rehabilitación vestibular personalizado y a los 12 meses postoperatorios presentaron una mejoría clínica significativa en comparación con el preoperatorio. Discusión: Las posibles opciones de tratamiento en estos pacientes resultan limitadas. En la literatura, se ha demostrado que la laberintectomía es un tratamiento eficaz para el tratamiento de síntomas vestibulares persistentes e incapacitantes, en los pacientes sin audición funcional. La calidad de vida de los mismos es reducida, y mejoraría significativamente después de la cirugía translaberintica y de un programa personalizado de rehabilitación vestibular. Conclusión: Debido a su eficacia comprobada, el abordaje translaberíntico y la resección de la lesión, acompañado de la realización un programa de rehabilitación vestibular, como estrategia de tratamiento para estos pacientes debe ser considerado.

Introduction: The incidence of disabling vestibular symptoms in vestibular schwannoma patients has been reported at roughly 10%. Despite their relative rarity, however, such symptoms can lead to physical and social limitations and reduce patients' quality of life. Unfortunately, published evidence on possible treatment options for vestibular schwannoma patients with disabling vestibular symptoms is limited. Objective: To report the functional impact of trans-labyrinthine microsurgery and vestibular rehabilitation, performed at our hospital, in two vestibular schwannoma patients with disabling vestibular symptoms. Methods: A prospective analysis was performed of two patients with a unilateral vestibular schwannoma, without serviceable hearing in their affected ear, and severely handicapped by attacks of rotatory vertigo and constant dizziness. Trans-labyrinthine surgery, with complete tumor resection, was performed in both patients. Preoperative and postoperative quality of life was measured using Dizziness Handicap Inventory (DHI) scores. Both patients also underwent a customized vestibular rehabilitation program and had a final evaluation 12 months post-operatively. Results: Relative to their preoperative evaluation, both patients experienced significant clinical improvement that persisted through 12 months of post-operative follow-up. Conclusions: Consistent with the few prior reports already published, we found that surgical removal of vestibular schwannomas by trans-labyrinthine surgery and vestibular rehabilitation was safe and effective for persistent, disabling vestibular symptoms. Postoperative vertigo and quality of life both improved significantly when microsurgery was combined with a personalized vestibular rehabilitation program. Disabling vestibular symptoms that impair quality of life in patients with vestibular schwannoma without serviceable hearing in the affected ear should be considered for trans-labyrinthine microsurgery and personalized vestibular rehabilitation.

Alucinosis peduncular: descripción de un caso y revisión del tema / Peduncular hallucinosis: a case report and topic review / Alucinose peduncular: descrição de um caso e revisão do assunto

La alucinosis peduncular es el término utilizado para describir una forma rara de alucinaciones visuales complejas, vívidas, coloridas y generalmente recurrentes que ocurren en relación a lesiones del tronco encefálico y el tálamo. Es una patología infrecuente y su fisiopatología es controvertida. Describimos el caso de una mujer de 38 años con alucinosis peduncular asociada a compresión extrínseca del tronco encefálico secundaria a un schwannoma vestibular. Analizamos las características clínicas y los mecanismos fisiopatológicos subyacentes.

Peduncular hallucinosis is a clinical condition characterized by vivid, colorful, complex visual hallucinations that often recur in time and are described in association with midbrain and thalamic lesions. It is a rare phenomenon and its precise pathophysiology is unknown. We describe the case of a 38-year-old woman who developed peduncular hallucinosis in relation to extrinsic compression of the midbrain secondary to a vestibular schwannoma. Clinical features and underlying pathophysiological mechanisms are discussed.

A alucinose peduncular é o termo usado para descrever uma forma rara de alucinações visuais complexas, vívidas, coloridas e geralmente recorrentes que ocorrem em relação às lesões do tronco encefálico e do tálamo. É uma patologia infreqüente e sua fisiopatologia é controversa. Descrevemos o caso de uma mulher de 38 anos de idade com alucinose peduncular associada à compressão extrínseca do tronco encefálico secundária ao schwannoma vestibular. Analisamos as características clínicas e os mecanismos fisiopatológicos subjacentes.

Fresado de la fosa subarcuata para liberar la arteria cerebelosa anteroinferior en una cirugía de un schwannoma vestibular / Reaming the subarcuate fossa to release the anteroinferior cerebellar artery in surgery for a vestibular schwannoma

Introducción: El abordaje suboccipital retrosigmoideo es la vía principal para la resección de los schwannomas vestibulares (SV). La relación vascular más constante de los nervios del conducto auditivo interno es la arteria cerebelosa anteroinferior (ACAI); pudiendo su recorrido presentarse como un serio obstáculo para la resección completa de la lesión. Descripción del caso: Paciente varón de 38 años, con diagnóstico presuntivo de SV por resonancia magnética (Grado T3B). Se realiza cirugía por vía retrosigmoidea. Se observa a la ACAI totalmente recubierta por tejido dural y óseo, cuya liberación fue posible mediante fresado en la fosa subarcuata. Se logra una exéresis completa del tumor. El paciente evolucionó durante el estado posoperatorio sin déficit neurológico agregado. Discusión: La ACAI ha sido descripta fijada a la duramadre y/o incrustada en el hueso de la fosa subarcuata en escasas publicaciones, impidiendo la resección completa de un SV, especialmente de la porción intracanalicular. Sin embargo, su liberación supone riesgo adicional de lesión vascular. Conclusión: La lesión de la ACAI puede ser causal de alta morbilidad, por lo que el neurocirujano debe estar preparado para reconocer y resolver este tipo de situaciones.

Introduction: A retrosigmoid suboccipital approach is the route most commonly utilized to resect vestibular schwannomas (VS). However, the anterior inferior cerebellar artery (AICA) usually runs adjacent to internal auditory canal nerves, and its course may severely impede total tumor resection. Case report: A 38-year-old male patient presented with presumed grade T3B VS, diagnosed by magnetic resonance imaging (MRI). Surgery was performed using a retrosigmoid approach, during which the AICA was identified to be completely covered by dural and bone tissue. Further drilling in the subarcuate fossa was necessary to release the AICI, allowing for total gross resection of the VS. No neurological deficits were observed post-operatively. Discussion: On rare occasion, the AICA has been described fixed to the dura and/or embedded within subarcuate fossal bone, thereby preventing removal of the intra-canalicular portion of the VS and, hence, total resection. However, AICA release adds the risk of vascular injury. Conclusion: Injury to the AICA may cause high morbidity in patients with a vestibular schwannoma. Neurosurgeons must be able to recognize and deal with certain anatomical configurations that place patients at particularly-high risk.

Peripheral Facial Palsy and Communicating Hydrocephalus as a Clinical Presentation of Hemorrhagic Vestibular Schwannoma: Case Report

The vestibular schwannoma is the most common extra-axial tumor of the posterior fossa. Hemorrhage associated with vestibular schwannomas has been described in less than 1% of the cases. The etiology remains unknown; however, some risk factors have been suggested, such as tumor size and tumor growth rate, the vascularity and histopathology of the tumor or even previous treatment with radiosurgery. The present case is of a 74-year-old female patient, who presented to our clinic in December of 2015 after a mild traumatic brain injury. In that context, she did a brain computed tomography (CT) scan and was diagnosed with a vestibular schwannoma­ an incidentaloma. It was decided at that time to treat the patient conservatively because of her comorbidities and the presentation of the disease. In March of 2017, the patient presented again to our clinic with a right peripheral facial paralysis (House-Brackmann [HB] grade IV-VI) and confusion. The CT scan revealed that bleeding around the vestibular schwannoma had caused the clinical presentation. We decided to treat the hydrocephalus with a ventriculoperitoneal shunt. At the time of her last follow-up visit, the confusion symptoms had resolved, and her right-sided facial function had improved to a HB grade II-VI.

Relationship of Vertigo and Postural Instability in Patients With Vestibular Schwannoma

OBJECTIVES: Growth of vestibular schwannomas (VS) causes progressive vestibular symptoms and postural instability. Since the tumor grows slowly, compensation of decaying vestibular input may decrease subjective symptoms of dizziness. This study aims to estimate the relationship of subjective vestibular symptoms and objective postural instability in patients with VS. METHODS: A retrospective review of 18 patients newly diagnosed with VS and with subjective vertigo symptoms was performed. The results of vestibular function tests including the sensory organization test (SOT) using computerized dynamic posturography, caloric test, and self-report measures of subjective dizziness handicap (Dizziness Handicap Inventory) and visual analogue scale were compared according to the onset of vertigo symptoms. RESULTS: In VS patients, SOT showed decreased equilibrium score for all vestibular function related conditions, condition (C) 5 and 6, and composite (COMP) score. COMP scores were not correlated with visual analogue scale or Dizziness Handicap Inventory scores. Acute onset group included six patients and insidious onset group, 12 patients. Equilibrium scores for C5 and C6, and COMP scores were lower for insidious onset group, but the difference was not statistically significant. CONCLUSION: Our findings confirmed postural instability is prevalent in VS patients. SOT parameters did not differ significantly between acute onset and insidious onset groups, but increased tumor size and canal weakness were noted in the insidious onset group. Clinicians should consider that postural instability is likely present even in patients who do not complain of acute vertigo, and appropriate counseling should be discussed with the patients.

Morbidity Rate of the Retrosigmoid versus Translabyrinthine Approach for Vestibular Schwannoma Resection

BACKGROUND AND OBJECTIVES: Controversy related to the choice of surgical approach for vestibular schwannoma (VS) resection remains. Whether the retrosigmoid (RS) or translabyrinthine (TL) approach should be performed is a matter of debate. In the context of a lack of clear evidence favoring one approach, we conducted a retrospective study to compare the morbidity rate of both surgical approaches. SUBJECTS AND METHODS: 168 patients underwent surgical treatment (2007-2013) for VS at our tertiary care center. There were no exclusion criteria. Patients were separated into two groups according to the surgical approach: TL group and RS group. Signs and symptoms including ataxia, headache, tinnitus, vertigo and cranial nerve injuries were recorded pre- and postoperatively. Surgical complications were analyzed. Perioperative facial nerve function was measured according to House-Brackmann grading system. RESULTS: Tumor resection was similar in both groups. Facial paresis was significantly greater in RS group patients preoperatively, in the immediate postoperative period and at one year follow-up (p < 0.05). A constant difference was found between both groups at all three periods (p=0.016). The evolution of proportion was not found to be different between both groups (p=0.942), revealing a similar rate of surgically related facial paresis. Higher rate of ataxic gait (p=0.019), tinnitus (p=0.039) and cranial nerve injuries (p=0.016) was found in RS group patients. The incidence of headache, vertigo, vascular complications, cerebrospinal fluid leak and meningitis was similar in both groups. No reported mortality in this series. CONCLUSIONS: Both approaches seem similar in terms of resection efficacy. However, according to our analysis, the TL approach is less morbid. Thus, for VS in which hearing preservation is not considered, TL approach is preferable.

Carcinoma epidermoide en senos paranasales con epistaxis / Epidermoid carcinoma in paranasal sinuses with epistaxis pretends vestibular schwannoma

El carcinoma epidermoide es un tumor maligno, infiltrante y destructor, que origina metástasis por vía linfática, hemática e invasión directa; en la zona nasosinusal es relativamente poco frecuente. Objetivo: identificar las características clínicas de esta patología para el correcto abordaje y tratamiento. Presentación de caso clínico: paciente femenina con carcinoma epidermoide en senos paranasales, 36 años, procedente de Villa de San Antonio, Honduras. En febrero de 2016 acude al Hospital Colonial de Comayagua por una obstrucción nasal derecha, concomitante epistaxis recurrente con coágulos del lado derecho. Posteriormente se presentaron dos episodios graves de epistaxis; después es referida a la Consulta Externa del Hospital Escuela Universitario, donde se encontró a la exploración física: órbita inflamada del ojo derecho, acompañada de pérdida de la sensibilidad superficial y profunda del lado derecho de la cara. Se realizó estudio histopatológico, que reportó tejido conectivo infiltrado por nidos neoplásicos con características malignas, formando agregados con apariencia epitelial. Se diagnosticó carcinoma epidermoide en fosa nasal derecha y región pterigomaxilar. Finalizados los procedimientos quirúrgicos recibió a 37 días de radioterapia profiláctica, con control posterior en oncología del Hospital General San Felipe. Conclusión: ante un paciente que presenta sangrado nasal constante con obstrucción, lagrimeo y una masa en senos paranasales, se debe sospechar de una patología neoplásica de acuerdo a los tipos más frecuentes en el área anatómica de origen; por lo tanto, una vez identificado, se debe realizar biopsia y marcadores tumorales para establecer de forma oportuna diagnóstico, pronóstico, presencia de metástasis y el tratamiento a seguir.

Maximum diameter versus volumetric assessment for the response evaluation of vestibular schwannomas receiving stereotactic radiotherapy

PURPOSE: To explore the feasibility of maximum diameter as a response assessment method for vestibular schwannomas (VS) after stereotactic radiosurgery or fractionated stereotactic radiotherapy (RT), we analyzed the concordance of RT responses between maximum diameters and volumetric measurements. MATERIALS AND METHODS: Forty-two patients receiving curative stereotactic radiosurgery or fractionated stereotactic RT for VS were analyzed retrospectively. Twelve patients were excluded: 4 did not receive follow-up magnetic resonance imaging (MRI) scans and 8 had initial MRI scans with a slice thickness >3 mm. The maximum diameter, tumor volume (TV), and enhanced tumor volume (ETV) were measured in each MRI study. The percent change after RT was evaluated according to the measurement methods and their concordances were calculated with the Pearson correlation. The response classifications were determined by the assessment modalities, and their agreement was analyzed with Cohen kappa statistics. RESULTS: Median follow-up was 31.0 months (range, 3.5 to 86.5 months), and 90 follow-up MRI studies were analyzed. The percent change of maximum diameter correlated strongly with TV and ETV (r(p) = 0.85, 0.63, p = 0.000, respectively). Concordance of responses between the Response Evaluation Criteria in Solid Tumors (RECIST) using the maximum diameters and either TV or ETV were moderate (kappa = 0.58; 95% confidence interval, 0.32-0.85) or fair (kappa = 0.32; 95% confidence interval, 0.05-0.59), respectively. CONCLUSION: The percent changes in maximum diameter and the responses in RECIST were significantly concordant with those in the volumetric measurements. Therefore, the maximum diameters can be used for the response evaluation of VS following stereotactic RT.

Clinical Feasibility of Suppression Head Impulse Test in Vestibulopathy Patients / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The suppression head impulse (SHIMP) test has emerged as one of the new vestibular function tests. The SHIMP test is an analysis of anti-compensatory saccadic movements in gazing moving targets as the head moves. In this study, we investigated the accuracy and sensitivity of the test. SUBJECTS AND METHOD: We analyzed the results of SHIMP test (gain, amplitude, and latency) in 24 cases, which included normal, vestibular neuritis, benign paroxysmal positional vertigo (BPPV), Meniere's disease, bilateral vestibular function loss, temporal bone fracture, tuberculosis meningitis and acoustic schwannoma patients. We also carried out a physical exam, audiologic study, video electronystagmography (vENG) and a conventional video head impulse test to evaluate the feasibility of SHIMP test in cases of vesitibulopathy. RESULTS: In patients with vestibulopathy, the analysis of SHIMP test indicated high sensitivity and accuracy, which were supported by accompanying audio-vestibular studies. Patients suspected with BPPV, vestibular neuronitis and Meniere's disease showed low vestibulo ocular reflex (VOR) gain and delayed anticompensatory saccade with smaller and more scattered amplitudes than the control. Patients with bilateral vestibular function loss, temporal bone fracture, tuberculosis meningitis, and acoustic schwannoma showed delayed latency, and small amplitude or few anticompensatory saccades. Finally, changes in the SHIMP test values might be a hint that patients had recovered from vestibular neuronitis and tuberculosis meningitis. CONCLUSION: We found the feasibility of SHIMP test in detecting the pathologic condition of VOR in vestibulopathy patients. We argue that the usefulness of SHIMP test might be extended to evaluating the effectiveness of rehabilitation.