Predictive value of Blink reflex and facial corticobulbar motor evoked potential in cerebellopontine angle tumor surgery.

OBJECTIVE: The current study examined the efficacy of the facial corticobulbar motor evoked potentials (FCoMEPs) and blink reflex (BR) on predicting postoperative facial nerve function during cerebellopontine angle (CPA) tumor surgery. METHODS: Data from 110 patients who underwent CPA tumor resection with intraoperative FCoMEPs and BR monitoring were retrospectively reviewed. The association between the amplitude reduction ratios of FCoMEPs and BR at the end of surgery and postoperative facial nerve function was determined. Subsequently, the optimal threshold of FCoMEPs and BR for predicting postoperative facial nerve dysfunction were determined by receiver operating characteristic curve analysis. RESULTS: Valid BR was record in 103 of 110 patients, whereas only 43 patients successfully recorded FCoMEP in orbicularis oculi muscle. A reduction over 50.3% in FCoMEP (O. oris) amplitude was identified as a predictor of postoperative facial nerve dysfunction (sensitivity, 77.1%; specificity, 83.6%). BR was another independent predictor of postoperative facial nerve deficit with excellent predictive performance, especially eyelid closure function. Its optimal cut-off value for predicting long-term postoperative eyelid closure dysfunction was was 51.0% (sensitivity, 94.4%; specificity, 94.4%). CONCLUSIONS: BR can compensate for the deficiencies of the FCoMEPs. The combination of BR and FCoMEPs can be used in CPA tumor surgery. SIGNIFICANCE: The study first proposed an optimal cut-off value of BR amplitude deterioration (50.0%) for predicting postoperative eyelid closure deficits in patients undergoing CPA tumor surgery.

Ependimomas de fosa posterior de tipo lateral en la edad pediátrica / Lateral-type posterior fossa ependymomas in pediatric population

Antecedentes y objetivos: Los ependimomas de fosa posterior de tipo lateral son un subtipo clínico e histológico característico, con un pronóstico poco favorable. Su incidencia es baja y su manejo quirúrgico es particularmente complejo. El objetivo del presente trabajo es revisar nuestra serie de ependimomas de fosa posterior de tipo lateral y contrastar nuestros resultados con la literatura disponible. Materiales y métodos: Sobre una muestra de 30 ependimomas intervenidos en neurocirugía pediátrica en los últimos 10 años, se identifican 7 casos de ependimomas de tipo lateral de la fosa posterior. Sobre esta serie de casos se realiza un estudio descriptivo retrospectivo. Resultados: La edad media de nuestros pacientes al diagnóstico fue de 3,75 años. Seis se presentaron con hidrocefalia. El volumen tumoral medio al diagnóstico fue de 61cm3. En 6 casos se llevó a cabo una resección completa y en un caso una resección casi completa. Cinco pacientes precisaron de forma transitoria una traqueostomía y una gastrostomía. La media de seguimiento fue de 58 meses. Durante este tiempo se produjo un caso de recidiva que posteriormente evolucionó a muerte. Cuatro casos de hidrocefalia posquirúrgica precisaron una derivación ventriculoperitoneal de LCR y 2 casos fueron manejados con ventriculostomía endoscópica. En la última revisión en consulta 4 pacientes llevaban una vida normal y 2 mostraban una restricción leve de la actividad de acuerdo con la escala de Lansky. Conclusiones: El objetivo del tratamiento quirúrgico de los ependimomas de tipo lateral de fosa posterior es la resección completa. Los déficits asociados a la disfunción de los pares bajos en nuestra serie fueron muy frecuentes pero transitorios. La progresiva caracterización molecular de estos tumores puede identificar diferentes grupos de riesgo sobre los que dirigir de forma adecuada la intensidad de los tratamientos adyuvantes.(AU)

Background and aims: Lateral-type posterior fossa ependymomas are a well-defined subtype of tumors both clinically and pathologically, with a poor prognosis. Their incidence is low and surgical management is challenging. The objective of the present work is to review our series of lateral-tye posterior fossa ependymomas and compare our results with those of previous series. Materials and methods: Among 30 cases of ependymoma operated in our pediatric department in the last 10 years, we identified seven cases of lateral-type posterior fossa ependymomas. We then performed a retrospective, descriptive study. Results: Mean age of our patients was 3.75 years. Six cases presented with hydrocephalus. Mean tumor volume at diagnosis was 61cc. A complete resection was achieved in six cases and a near-total resection in one patient. Five patients transiently required a gastrostomy and a tracheostomy. Mean follow-up was 58 months. One case progressed along this period and eventually died. Four cases of hydrocephalus required a ventriculoperitoneal CSF shunt and two were managed with a third ventriculostomy. At last follow-up four patients carried a normal life and two displayed a mild restriction according to Lansky's scale. Conclusions: The aim of surgical treatment in lateral-type posterior fossa ependymomas is complete resection. Neurological deficits associated to lower cranial nerve dysfunction are common but transient. Deeper genetic characterization of these tumors may identify risk factors that guide stratification of adjuvant therapies.(AU)

Guía de práctica clínica sobre el manejo del schwannoma vestibular / Clinical practice guideline on the management of vestibular schwannoma

Introducción: El schwannoma vestibular (SV) es el tumor más frecuente del ángulo pontocerebeloso. La mayor accesibilidad a las pruebas radiológicas ha incrementado su diagnóstico. Teniendo en cuenta las características del tumor, la clínica y la edad del paciente se han propuesto tres estrategias terapéuticas, observación, cirugía o radioterapia. La elección de la más adecuada para cada paciente es un motivo de controversia frecuente. Material y métodos: El presente trabajo incluye una revisión exhaustiva sobre cuestiones relativas al SV que pueden servir de guía clínica en el manejo de pacientes con estas lesiones. La presentación se ha orientado en forma de preguntas que el clínico se hace habitualmente y las respuestas están redactadas y/o revisadas por un panel de expertos nacionales e internacionales consultados por la Comisión de Otología de la SEORL-CCC. Resultados: Se ha elaborado un listado con los 13 bloques temáticos más controvertidos sobre el manejo del SV en forma de 50 preguntas y se han buscado las respuestas a todas ellas mediante una revisión sistemática de la literatura (artículos publicados en PubMed y Cochrane Library entre 1992 y 2023 sobre cada bloque temático). Treinta y tres expertos, liderados por la Comisión de Otología de la SEORL-CCC, han analizado y discutido todas las respuestas. En el Anexo 1 pueden encontrarse 14 preguntas adicionales divididas en cuatro bloques temáticos. Conclusiones: Esta guía de práctica clínica sobre el manejo del SV ofrece respuestas consensuadas a las preguntas más habituales que se plantean sobre este tumor. La ausencia de suficientes estudios prospectivos hace que los niveles de evidencia sobre el tema sean en general medios o bajos. Este hecho incrementa el interés de este tipo de guías de práctica clínica elaboradas por expertos.(AU)

IntroductionVestibular schwannoma (VS) is the most common tumour of the cerebellopontine angle. The greater accessibility to radiological tests has increased its diagnosis. Taking into account the characteristics of the tumour, the symptoms and the age of the patient, three therapeutic strategies have been proposed: observation, surgery or radiotherapy. Choosing the most appropriate for each patient is a frequent source of controversy. Material and methods: This paper includes an exhaustive literature review of issues related to VS that can serve as a clinical guide in the management of patients with these lesions. The presentation has been oriented in the form of questions that the clinician usually asks himself and the answers have been written and/or reviewed by a panel of national and international experts consulted by the Otology Commission of the SEORL-CCC. Results: A list has been compiled containing the 13 most controversial thematic blocks on the management of VS in the form of 50 questions, and answers to all of them have been sought through a systematic literature review (articles published on PubMed and Cochrane Library between 1992 and 2023 related to each thematic area). Thirty-three experts, led by the Otology Committee of SEORL-CCC, have analyzed and discussed all the answers. In Annex 1, 14 additional questions divided into 4 thematic areas can be found. Conclusions: This clinical practice guideline on the management of VS offers agreed answers to the most common questions that are asked about this tumour. The absence of sufficient prospective studies means that the levels of evidence on the subject are generally medium or low. This fact increases the interest of this type of clinical practice guidelines prepared by experts.(AU)

[To the origins of surgery for acoustic neuromas]. / K istokam khirurgii nevrinom slukhovogo nerva.

Acoustic neuroma is one of the most common tumors of the posterior cranial fossa. Its removal is always a challenge for the neurosurgeon and the patient. The history of surgery for acoustic neuromas is inextricably linked with the history of neurosurgery in general. The modern surgical community must know history and be able to use it. Only then will the development of surgery lead to the preservation of the quality of life of patients. In the history of surgery for acoustic neuromas, the stages of its development are clearly visible from the description of the clinical picture through the study of the anatomy of the cerebellopontine angle to modern microsurgical removal.

El papel de la RMN en el diagnóstico de la patología audiovestibular / The role of MRI in the diagnosis of audio-vestibular pathology

Introducción y objetivo: El schwanoma vestibular es un tumor benigno, de lento crecimiento que aparece en la vaina de mielina que rodea al nervio vestibular. Estos tumores representan el 6% de todos los tumores intracraneales y el 85% de los tumores del ángulo pontocerebeloso. El síntoma de aparición más frecuente es la hipoacusia unilateral, seguida del acúfeno unilateral, inestabilidad, vértigo, cefalea e incluso, en determinados casos, parestesias faciales o parálisis facial. Todo ello depende del tamaño del tumor y su localización. Actualmente, el diagnóstico de estos tumores se realiza mediante la realización de una historia clínica completa, pruebas complementarias audiológicas y vestibulares y, como prueba de imagen, una RMN. Según el American College of Radiology (ACR) la RMN de base de cráneo y conductos auditivos internos es la prueba de elección para el diagnóstico del schwanoma vestibular. Ésta puede ser con y sin contraste (generalmente Gadolinio) y permite detectar tumores de muy pequeño tamaño. Nuestro objetivo con este trabajo es aportar evidencia científica que permita al profesional seguir un protocolo diagnóstico de los schwanomas vestibulares y, consecuentemente, optimizar los recursos hospitalarios. Método: De una muestra total de 685 se revisaron todas las historias clínicas de los pacientes a los que se les había solicitado una RMN por síntomas audiovestibulares (hipoacusia, acúfeno, vértigo, parálisis facial y otros). Se llevó a cabo un estudio descriptivo y observacional en el cual se mostraban los síntomas que había padecido cada paciente, el motivo de petición de la prueba de imagen, el diagnóstico final y el tipo de resonancia magnética empleada. Con toda esta información se creó una base de datos y se analizaron los resultados estadísticamente. Resultados: ... (AU)

Introduction and objective: Vestibular schwannoma is a benign, slow-growing tumor that appears in the myelin sheath surrounding the vestibular nerve. These tumors represent 6% of all intracranial tumors and 85% of tumors in the cerebellopontine angle. The most common initial symptom is unilateral hearing loss, followed by unilateral tinnitus, instability, vertigo, headache, and, in certain cases, facial paresthesia or facial paralysis. All of these symptoms depend on the size and location of the tumor. Currently, the diagnosis of these tumors is made through a complete medical history, complementary audiological and vestibular tests, and, as an imaging test, an MRI. According to the American College of Radiology (ACR), the MRI of the skull base and internal auditory canals is the gold standard for diagnosing vestibular schwannoma. This can be performed with and without contrast (usually Gadolinium) and allows the detection of very small tumors. Our objective with this article is to provide scientific evidence that enables professionals to diagnose vestibular schwannomas and optimize hospital resources. Method: From a total sample of 685 patients, all medical records of them who had been requested an MRI for audiovestibular symptoms (hearing loss, tinnitus, vertigo, facial paralysis, and others) were reviewed. A descriptive and observational study was carried out, showing the symptoms experienced by each patient, the reason for requesting the imaging test, the final diagnosis, and the type of MRI used. With all this information, a database was created, and the results were analyzed statistically. Results: ... (AU)

Effect of deep learning-based reconstruction on high-resolution three-dimensional T2-weighted fast asymmetric spin-echo imaging in the preoperative evaluation of cerebellopontine angle tumors.

PURPOSE: We aimed to evaluate the effect of deep learning-based reconstruction (DLR) on high-spatial-resolution three-dimensional T2-weighted fast asymmetric spin-echo (HR-3D T2-FASE) imaging in the preoperative evaluation of cerebellopontine angle (CPA) tumors. METHODS: This study included 13 consecutive patients who underwent preoperative HR-3D T2-FASE imaging using a 3 T MRI scanner. The reconstruction voxel size of HR-3D T2-FASE imaging was 0.23 × 0.23 × 0.5 mm. The contrast-to-noise ratios (CNRs) of the structures were compared between HR-3D T2-FASE images with and without DLR. The observers' preferences based on four categories on the tumor side on HR-3D T2-FASE images were evaluated. The facial nerve in relation to the tumor on HR-3D T2-FASE images was assessed with reference to intraoperative findings. RESULTS: The mean CNR between the tumor and trigeminal nerve and between the cerebrospinal fluid and trigeminal nerve was significantly higher for DLR images than non-DLR-based images (14.3 ± 8.9 vs. 12.0 ± 7.6, and 66.4 ± 12.0 vs. 53.9 ± 8.5, P < 0.001, respectively). The observer's preference for the depiction and delineation of the tumor, cranial nerves, vessels, and location relation on DLR HR-3D T2FASE images was superior to that on non-DLR HR-3D T2FASE images in 7 (54%), 6 (46%), 6 (46%), and 6 (46%) of 13 cases, respectively. The facial nerves around the tumor on HR-3D T2-FASE images were visualized accurately in five (38%) cases with DLR and in four (31%) without DLR. CONCLUSION: DLR HR-3D T2-FASE imaging is useful for the preoperative assessment of CPA tumors.

Unilateral Multifocal Inner Ear and Internal Auditory Canal or Cerebellopontine Angle Cochleovestibular Schwannomas-Genetic Analysis and Management by Surgical Resection and Cochlear Implantation.

OBJECTIVE: To describe the genetic characteristics and the management of two very rare cases of unilateral multifocal inner ear and internal auditory canal or cerebellopontine angle cochleovestibular schwannomas not being associated to full neurofibromatosis type 2-related schwannomatosis. PATIENTS: In a 29-year-old man and a 55-year-old woman with single-sided deafness multifocal unilateral cochleovestibular schwannomas were surgically resected, and hearing was rehabilitated with a cochlear implant (CI). Unaffected tissue was analyzed using next generation sequencing of the NF2 gene. Tumor tissue was analyzed using a 340-parallel sequencing gene panel. MAIN OUTCOME MEASURES: Mutations in the NF2 gene, word recognition score for monosyllables at 65 dB SPL (WRS 65 ) with CI. RESULTS: No disease-causing mutation was detected in the examined sequences in blood leucokytes. All tumor samples revealed, among others, somatic pathogenic NF2 mutations. While the anatomically separate tumors in case 1 were likely molecular identical, the tumors in case 2 showed different genetic patterns. WRS 65 was 55% at 6 years of follow-up and 60% at 4.5 years of follow-up, respectively. CONCLUSIONS: The occurrence of multifocal unilateral cochleovestibular schwannomas without pathogenic variants in NF2 in non-affected blood leucocytes can be associated with mosaic NF2 -related schwannomatosis (case 1), or with likely sporadic mutations (case 2) and may be overlooked due to their extreme rarity. Although challenging, successful hearing rehabilitation could be achieved through surgical resection of the tumors and cochlear implantation.

Postoperative Herpes Viral Infections in Neurosurgery - An Experience and Arguments for and against the Plausible Hypotheses.

BACKGROUND: The literature contains several reports of herpes recrudescence after neurosurgery. We analyze our experience by vindicating or refuting the existing plausible hypotheses. MATERIAL AND METHODS: This is a retrospective review of all neurosurgical cases that developed postoperative herpes infection between January 2016 and June 2020. RESULTS: Six patients developed herpes infection after vestibular schwannoma (VS) surgery. Other neurosurgical cases did not develop herpes infection. There were five females and one male, with a mean age of 44.1 years. Four out of six patients developed delayed facial palsy (DFP) and did not improve after antiviral treatment. Postoperative herpes infections were 0.2% among all operated patients, 3.07% among all cerebellopontine (CP) angle surgeries, and 5.6% among VS surgeries. CONCLUSIONS: To date, none of the plausible hypotheses satisfactorily addresses all aspects of viral recrudescence. The etiology may be multi-factorial, and in all cases of unexplained clinical deterioration, herpes infection needs consideration in the differential diagnosis.

Arachnoid Cyst of the Cerebellopontine Angle: A Systematic Literature Review.

OBJECTIVE: The role of surgical management of arachnoid cyst (AC) of the cerebellopontine angle (CPA) is uncertain. This topic has remained controversial with varying contradictory recommendations in the literature, which is limited to mostly case reports. We aimed to provide a comprehensive summary and analysis of symptoms, operative techniques, outcomes, and recurrence of all available surgical cases of AC of the CPA to date. METHODS: A systematic literature search was performed in May 2022 querying several scientific databases. Inclusion criteria specified all studies and case reports of patients with AC located at the CPA for which any relevant surgical procedures were performed. RESULTS: A total of 55 patients from the literature and 5 treated at our institution were included. Mean patient age was 29 years (range, 0.08-79 years), with nearly twice (1.7×) as many female as male patients (37 female, 22 male). Headaches (35%), hearing loss (30%), vertigo (22%), and ataxia (22%) were the most common presentations. Following surgery, 95% experienced symptom improvement, with complete resolution in 64%. Of patients with hearing loss, 44% reported a return to normal. The rate of mortality was 1.69%, and 10% of tumors recurred (mean follow-up 2.3 years [range, 0-15 years]. CONCLUSIONS: Symptomatic AC of the CPA is rare. It exhibits a proclivity for females and commonly manifests with headache, hearing loss, vertigo, and ataxia. While careful selection for surgical candidacy is needed and intervention should be reserved for patients with severe symptoms, surgical decompression is an effective tool for symptom alleviation and recovery.

Introducing endoscopic assistance on routinary basis for vestibular schwannomas resection: A single centre acceptance analysis.

OBJECTIVE: The use of endoscopic assistance in retrosigmoid approach for tumors of the cerebellopontine angle brought undoubted technological advantages in skull base surgery. Nonetheless, the use of the endoscope is not as widespread as it could be. The aim of the study is to analyze the impressions of neurosurgeons and otologists with different experience in vestibular schwannoma surgery, experiencing the introduction of the endoscope in surgical daily practice. METHODS: All patients undergoing vestibular schwannoma surgery were recruited in the period from January 2019 to December 2020. The endoscope-assistance and a minimum follow-up of 12 months were considered inclusion criteria. An eight items questionnaire was administered to the surgeons who used endoscope-assistance during surgery. RESULTS: A total number of 20 patients were recruited. Five surgeons experienced the use of 0° and 45° optics in the "pre-resection" and "intra-meatal" phases of the procedures. The survey gave positive feedbacks on the introduction of the endoscope in vestibular schwannoma resection. The main drawback was the difficulty to manage the use of angled optics. CONCLUSIONS: Despite the known limitations of the study, the idea of investigating surgeons' impressions on the use of the endoscope could be another motif to explain why this instrument and its diffusion is limited despite its advantages in vestibular schwannoma surgery.

Meningiomas de ángulo pontocerebeloso: tratamiento con radiocirugía mediante LINAC / Cerebellopontine angle meningiomas: LINAC stereotactic radiosurgery treatment

Objetivos Evaluar el resultado del tratamiento con radiocirugía estereotáctica (RC) mediante acelerador lineal (LINAC) en meningiomas de ángulo pontocerebeloso (APC). Métodos Analizamos 80 pacientes diagnosticados de meningiomas de APC entre los años 2001-2014, tratados mediante RC. El 81,9% (n=68) fueron mujeres, con una media de edad de 59,1años (32-79). La RC se aplicó como tratamiento primario en el 83,7% (n=67), y en el 16,3% (n=13) como adyuvante a la cirugía. El tratamiento con RC se lleva a cabo en un acelerador lineal (Varian600, 6MeV) con micromultiláminas M3 (BrainLab) y marco estereotáxico. El volumen tumoral medio fue de 3,14cm3 (0,34-10,36cm3) y la dosis de cobertura media fue de 14Gy (12-16Gy). Se realiza un análisis descriptivo retrospectivo, un análisis de supervivencia método Kaplan-Meier y se contrasta la relación entre las variables del estudio mediante análisis univariados. Resultados Tras un periodo de seguimiento medio de 86,9meses (12-184), la tasa de control tumoral fue del 92,8% (n=77). Se comprobó una reducción global del volumen tumoral al final del estudio del 32,8%, con un volumen medio final de 2,11cm3 (0-10,35cm3). La tasa de supervivencia libre de progresión fue del 98% al año, del 95% a los 5años y del 83,3% a los 10 y 12años. El mayor volumen tumoral previo al tratamiento (p=0,047) se relacionó con la progresión. Se produjo la mejoría clínica en el 26,5% (n=21) de los casos y el deterioro en el 16,2% (n=13); el empeoramiento se relaciona con la dosis de radiación que recibe el troncoencéfalo (p=0,02). Respecto a las complicaciones, el 8,7% (n=7) sufrieron deterioro de la audición, el 5% (n=4) radionecrosis y el 3,7% (n=3) neuropatía del Vpar craneal. La dosis máxima alcanzada (p=0,037) y el tamaño tumoral inicial (p=0,033) se relacionan con la progresión de la hipoacusia, y el desarrollo de radionecrosis, con la dosis máxima alcanzada (p=0,037) (AU)

Objectives To evaluate the efficacy of treatment with linear accelerator-based stereotactic radiosurgery (LINAC) in cerebellopontine angle meningiomas. Methods We analyzed 80 patients diagnosed with cerebellopontine angle meningiomas between 2001 and 2014, treated with stereotactic radiosurgery (SRS), of whom 81.9% (n=68) were women, with an average age of 59.1years (32-79). SRS was applied as primary treatment in 83.7% (n=67) and in 16.3% (n=13) as an adjuvant treatment to surgery. SRS treatment was provided using LINAC (Varian600, 6MeV) with M3 micromultilamines (brainLab) and stereotactic frame. The average tumor volume was 3.12cm3 (0.34-10.36cm3) and the coverage dose was 14Gy (12-16Gy). We performed a retrospective descriptive analysis and survival analysis was performed with the Kaplan-Meier method and multivariate analysis to determine those factors predictive of tumor progression or clinical improvement. Results After an average follow-up period of 86.9months (12-184), the tumor control rate was 92.8% (n=77). At the end of the study, there was an overall reduction in tumor volume of 32.8%, with an average final volume of 2.11cm3 (0-10.35cm3). The progression-free survival rate at 5, 10 and 12years was 98%, 95% and 83.3% respectively. The higher tumor volume (P=.047) was associated with progression. There was clinical improvement in 26.5% (n=21) of cases and clinical worsening in 16.2% (n=13). Worsening is related to the radiation dose received by the brainstem (P=.02). Complications were 8.7% (7 cases) of hearing loss, 5% (4 cases) of brain radionecrosis, and 3.7% (3 cases) of cranial nerveV neuropathy. Hearing loss was related to initial tumor size (P=.033) and maximum dose (P=.037). The occurrence of radionecrosis with the maximum dose (P=.037). Conclusions Treatment of cerebellopontine angle meningiomas with single-dose SRS using LINAC is effective in the long term. Better tumor control rates were obtained in patients with small lesions (AU)

Cerebellopontine angle tumor presenting as acute audiovestibular syndrome.

BACKGROUND: Acute audiovestibular deficits may be a harbinger of vestibular schwannoma (VS). OBJECTIVE: To investigate clinical and laboratory features of 25 consecutive patients with VS presenting with acute audiovestibular deficits. METHODS: A symptomatic combination of acute audiovestibular deficits was investigated. Audiometric and vestibular function tests, and internal auditory canal magnetic resonance imaging (IAC MRI) results were evaluated. RESULTS: Varying combinations of symptoms may develop in VS patients with acute audiovestibular deficits, of whom sudden hearing loss (HL) without acute vertigo or acute facial nerve palsy (FNP) was most common. The most common audiometric configuration was high-tone hearing loss, and no patient showed low-tone hearing loss. IAC MRI demonstrated that the tumor had an intracanalicular portion and attachment to the bony IAC wall in all patients and widened the IAC wall in some patients. CONCLUSION: Different symptomatic combinations of acute audiovestibular deficits may develop in patients with VS. Awareness about the possibility of VS as a cause of sudden HL, acute vertigo, and acute FNP, as well as subsequent IAC MRI scanning is vital to earlier diagnosis of VS in these patients.

Fully neuroendoscopic resection of cerebellopontine angle tumors through a retrosigmoid approach: a retrospective single-center study.

The objective of this study is to preliminarily investigate the surgical safety, efficacy, techniques, and clinical value of fully neuroendoscopic surgery for the resection of cerebellopontine angle (CPA) tumors via a retrosigmoid approach. The clinical data of 47 cerebellopontine angle area (CPA) tumors that were treated by full neuroendoscopic surgery from June 2014 to June 2023 were retrospectively analyzed. The efficacy and advantages of the surgical techniques were evaluated based on indicators such as duration of the surgery, neuroendoscopic techniques, intraoperative integrity of nerves and blood vessels, extent of tumor resection, outcomes or postoperative symptoms, and incidence of complications. The 47 cases of cerebellopontine angle tumors include 34 cases of epidermoid cysts, 7 cases of vestibular schwannomas, and 6 cases of meningiomas. All patients underwent fully neuroendoscopic surgery. Twenty tumors were removed using the one-surgeon two-hands technique, and 27 tumors were removed using the two-surgeons four-hands technique. The anatomical integrity of the affected cranial nerves was preserved in all 47 cases. None of the patients suffered a postoperative hemorrhage, cerebrospinal fluid leak, and aseptic or septic meningitis, or died. The rate of total tumor resection was 72.3% (34/47), and the symptom improvement rate was 89.4% (42/47). All patients were followed up for 2 to 12 months, and none died nor showed any signs of tumor recurrence. By analyzing 47 fully neuroendoscopic resections of CPA tumors using the posterior sigmoid sinus approach in our center, we believe that such method allows complete, safe, and effective resection of CPA tumors and is thereby worthy of clinical promotion.

Fully endoscopic microvascular decompression for trigeminal neuralgia: technical note and early outcomes.

Microscopic microvascular decompression (MVD) has been considered a curative and reliable method for treating classical trigeminal neuralgia (TN) for decades. Endoscopy can provide bright illumination and a panoramic view, which enhances the visualization of the posterior fossa. In view of the above advantages of endoscopy, it gradually became an option for MVD for treating TN. This study was performed to evaluate the advantages of fully endoscopic MVD for treating TN and is presented with a description of our operative technique. From January 2020 to January 2022, 95 classical TN patients underwent fully endoscopic MVD performed by the same surgeon and assistant in our department. The assistant held the endoscope, and the surgeon operated. Brain stem auditory evoked potentials (BEMPs) were routinely monitored. For every patient, the neurovascular conflict was identified, and complete decompression was achieved. The Barrow Neurological Institute (BNI) pain intensity score was used to evaluate the degree of facial pain. The intraoperative findings, postoperative outcomes, and complications were analyzed. Immediately after the operation, 93 patients (97.9%) achieved complete pain relief (BNI score of I). Two patients (2.1%) still had some pain, but it could be adequately controlled with medicine (BNI score of III). During the 12-36 months of follow-up, recurrence was found in 3 patients (3.2%), including one patient (1.1%) with a BNI score of II and 2 patients (2.1%) with a BNI score of III. Complications were found in 5 patients (5.3%), including facial numbness in 3 patients (3.2%), vertigo in one patient (1.1%), and headache in one patient (1.1%). There were no cases of mortality, stroke, hearing impairment, facial paralysis, or other complications. Fully endoscopic MVD is a safe and effective method for treating TN. It provides bright illumination and a panoramic view for surgeons to better observe neurovascular conflicts in deep areas of the cerebellopontine angle (CPA).

Simultaneous cochlear implantation during resection of a cerebellopontine angle meningioma: case report.

Cerebellopontine angle (CPA) meningiomas commonly involve the internal auditory canal (IAC). We report a case of a 68-year-old lady with idiopathic profound bilateral deafness with a meningioma which was discovered on workup for cochlear implantation. We performed simultaneous excision of her CPA and IAC meningioma with insertion of a cochlear implant (CI). She regained functional hearing with marked improvement in quality of life. Intraoperative electrophysiological testing can be used to confirm preservation of the cochlear nerve enabling simultaneous implantation which is preferable for clinical and logistical reasons. This creates an option for hearing rehabilitation at the time of IAC/CPA tumour surgery in appropriate patients.

The cerebellopontine angle cistern volumetric differences in trigeminal neuralgia patients with and without vertebrobasilar compression: a case-matched study.

Previous studies have indicated that the small cerebellopontine angle (CPA) cistern plays a role in the pathogenesis of trigeminal neuralgia (TN), but they are likely not involved in TN associated with vertebrobasilar artery (VBA) compression because of its rarity. Forty-four patients with VBA-associated TN and 44 age-, sex-, and hypertension-matched TN patients without VBA compression (non-VBA-associated) were included. All patients underwent high-resolution MRI. The CPA cistern volumes were measured bilaterally. The presence of vertebrobasilar dolichoectasia (VBD) and laterality of the vertebrobasilar junction (VBJ) were observed. The CPA cistern volume on the affected side was smaller than the unaffected side (714.4 ± 372.8 vs 890.2 ± 462.2 mm3, p < 0.001) in non-VBA-associated TN patients, while VBA-associated TN patients show a larger CPA cistern on the affected side than the unffected side (1107.0 ± 500.5 vs 845.3 ± 314.8 mm3, p < 0.001). The prevalence of VBD was higher in patients with VBA-associated TN than in matched non-VBA-associated TN patients (90.9% vs 4.5%, p < 0.001). A positive correlation between the laterality of VBJ and the affected side was found in the VBA-associated TN group (p < 0.0001). Large CPA cistern may be a neuroradiological feature of VBA-associated TN, and most of the VBA-associated TN is accompanied by VBD. The presence of VBD and the lateral shift of VBJ may expand the CPA cistern by squeezing the surrounding tissue on the affected side and also increase the chance of VBA compression on the trigeminal nerve, resulting in the genesis of VBA-associated TN.

Nationwide clinico-epidemiological treatment analysis of adult patients with tumors of cerebellopontine angle and internal acoustic meatus in Poland during 2011-2020.

OBJECTIVE: The aim of this study is to report the epidemiologic characteristics of tumors of the cerebellopontine angle (CPAT) and internal acoustic meatus in adult Polish population throughout the second decade of XXI century and to analyze their treatment. MATERIAL AND METHODS: A retrospective analysis of patients with cerebellopontine angle (CPA) and internal acoustic meatus tumors diagnosed in Poland in 2011-2020 was performed. Data recorded in the National Health Fund (NHF) database were analyzed. International Classification of Diseases codes (ICD-9 and ICD-10) were used to identify study group patients and treatment procedures. RESULTS: From 2011 to 2020 6,173 Polish adult patients were diagnosed with cerebellopontine angle and internal acoustic meatus tumors. The average incidence in Poland is 1.99 per 100,000 residents/year. It mostly affects women (61.64%), and the average age of patients is 53.78 years. The incidence has steadily increased over the past decade. Treatment has changed significantly over the years, with a definite increase in the number of patients treated with radiotherapy (from 0.54 to 19.34%), and a decrease in surgical therapies (from 41.67 to 6.8%). The most common symptoms were vertigo and/or dizziness (43.48%) and sensorineural hearing loss (39.58%). 4.65% of patients suffered from sudden deafness, in this group of patients the risk of CPAT detection was the highest (6.25 / 1000 patients). CONCLUSIONS: The total incidence of CPAT and demographic characteristics of patients were comparable to other studies. Our study demonstrated the increased number of patients are being treated with radiotherapy and fewer with microsurgery. Sudden sensorineural hearing loss (SSNHL) is an uncommon manifestation of CPAT but proper diagnosis should be undertaken because the risk of diagnosis such tumors is greater in this group.