A Case Report of Malignant Cerebellopontine Angle Lesion Highlighting the Interdisciplinary Diagnostic Challenge in the Case of Unilateral Progressive Hearing Loss.

The authors present the case of a young boy who experienced progressive unilateral hearing loss initially believed to be unrelated to any other medical condition. Methods: The patient received a thorough evaluation, which included a comprehensive battery of audiological tests, a CT scan, and a gadolinium-enhanced MRI. Results: A repeated imaging investigation revealed the presence of a mass that mimicked a vestibular schwannoma (VS), but despite this, the boy was ultimately diagnosed with cerebral manifestations of B-cell acute lymphoblastic leukemia (B-ALL). Conclusions: Cerebral lesions originating from the internal auditory canal are rare in cases of B-ALL. In this case, the initial signs and symptoms of the disease were solely related to the audiovestibular system, making the diagnostic process particularly complicated. Unilateral hearing loss cases may indicate the presence of potentially life-threatening conditions, even if the hearing loss appears to be clinically non-syndromic. For these reasons, unilateral hearing losses necessitate a comprehensive interdisciplinary diagnostic approach from the very start of auditory manifestation and, in particular, if the hearing impairment demonstrates threshold progression.

Arteriovenous malformations in the cerebellopontine angle: assessment of the "backdoor resection" technique and microsurgical results in 38 patients.

OBJECTIVE: Posterior fossa arteriovenous malformations (AVMs) represent 7% to 15% of all intracranial AVMs and are associated with an increased risk of hemorrhage, morbidity, and mortality compared with supratentorial AVMs, thus prompting urgent and definitive treatment. Cerebellopontine angle (CPA) AVMs are a unique group of posterior fossa AVMs incorporating characteristics of brainstem and cerebellar lesions, which are particularly amenable to microsurgical resection. This study reports the clinical, radiological, operative, and outcome features of patients with CPA AVMs in a large cohort. METHODS: The authors conducted a single-surgeon, 2-institution retrospective cohort study of all consecutive patients with CPA AVMs treated with microsurgical resection during a 25-year period. RESULTS: CPA AVMs represented 22% (38 of 176) of all infratentorial AVMs resected by the senior author. Overall, 38 patients (22 [58%] male and 16 [42%] female) met the study inclusion criteria and were analyzed. Most patients presented with hemorrhage (n = 29, 76%). The median age at surgery was 56 (range 6-82) years. Subtypes included 22 (58%) petrosal cerebellar AVMs, 11 (29%) lateral pontine AVMs, and 5 (13%) AVMs involving both the brainstem and cerebellum. Most AVM niduses were small (< 3 cm; n = 35, 92%) and compact (n = 31, 82%). Fourteen (37%) patients harbored flow-related aneurysms. Twenty (53%) patients underwent preoperative embolization. Complete angiographic obliteration was achieved with microsurgery in 35 (92%) patients. Five (13%) patients with poor neurological conditions at presentation died before hospital discharge. Of the 7 (18%) patients with new postoperative neurological deficits, 5 had transient deficits. The median (interquartile range) follow-up was 1.7 (0.5-3.2) years; 32 (84%) patients were alive at last follow-up, and 30 (79%) had achieved a favorable neurological outcome (modified Rankin Scale [mRS] score 0-2). The only independent predictor of unfavorable postoperative outcome (mRS score 3-6) was the preoperative mRS score (p = 0.002). CONCLUSIONS: CPA AVMs are unique posterior fossa lesions, including petrosal cerebellar and lateral pontine AVMs. The "backdoor resection" technique provides a safe and efficient strategy with high obliteration rates and a low risk of treatment-related morbidity. Microsurgical resection should be considered the frontline treatment for most CPA AVMs, except for those with a significant diffuse brainstem component.

Facial nerve electrical motor evoked potential in cerebellopontine angle tumors for its anatomical and functional preservation.

Background: Among the technical measures to preserve facial nerve (FN) function, intraoperative neuromonitoring has become mandatory and is constantly being scrutinized. Hence, to determine the efficacy of FN motor evoked potentials (FNMEPs) in predicting long-term motor FN function following cerebellopontine angle (CPA) tumor surgery, an analysis of cases was done. Methods: In 37 patients who underwent CPA surgery, FNMEPs through corkscrew electrodes positioned at C5-C6 and C6-C5 (C is the central line of the brain as per 10-20 EEG electrode placement) were used to deliver short train stimuli and recorded from the orbicularis oculi, oris, and mentalis muscles. Results: In 58 patients, triggered electromyography (EMG) was able to identify the FN during resection of tumor, but 8 out of these (4.64%) patients developed new facial weakness, whereas 3 out of 38 (1.11%) patients who had intact FN function MEP (decrement of FN target muscles - CMAPs amplitude peak to peak >50-60%), developed new facial weakness (House and Brackmann grade II to III). Conclusion: The FNMEP has significant superiority over triggered EMG when tumor is giant and envelops the FN.

Role of Neuroradiological Imaging in Progressive Sensorineural Hearing Loss: A Retrospective Study.

Aim: Our aim was to determine prevalence and type of neuro-radiological lesions detected on screening Magnetic Resonance Imaging (MRI) of brain in patients presenting with progressive sensorineural hearing loss in otorhinolaryngology clinic. Materials and Methods: This retrospective study included 96 screening magnetic resonance imaging MRI brain scans of patients who presented with progressive sensorineural hearing loss in department of otorhinolaryngology. The clinical and radiological data was collected and analysed. Results: Out of 96 screening MRI brain, 19 (19.8%) had positive findings. The commonest imaging finding was presence of vascular loop around facial and vestibulocochlear nerve root complex in 9 cases (9.4%) followed by presence of a cerebellopontine angle lesions in 5 cases (5.2%). The mean age of all patients was 48.5 years and those with positive screening MRI was 40.6 years. A gender gap was noticed with female being 22 (22.9%) in number against 74 (77.1%) males. Conclusion: This is the first retrospective study to determine prevalence and type of neuro-radiological lesions detected on screening magnetic resonance imaging in patients with progressive sensorineural hearing loss. We recommend screening MRI brain in patients with progressive SNHL aged below 60 years and all the described neuroradiological finding provide differential diagnosis. Definition and classification of progressive sensorineural hearing loss should be formulated to standardize the management. Further multi-institutional studies are required to identify social, occupational, genetic, or other factors that can cause gender disparity in patients with progressive SNHL.

Retrolabyrinthine approach to the lateral skull base: The value of preoperative temporal bone CT analysis.

PURPOSE: The most used neurosurgical approach to reach cerebellar-pontine angle is the retrosigmoid route. This article describes the presigmoid approach which requires excellent knowledge of the labyrinthine block together with quantitative analysis of temporal bone CT. METHODS: CT-based quantitative measurements were obtained in patients undergoing vestibular neurectomy with a presigmoid approach. Eighteen patients were enrolled, and five measures were taken: Trautmann's area, the petro-clival angle, presigmoid dura length and its angle. The relationship between these measurements and hospitalization days, operating times, and complications was explored. RESULTS: The posterior semicircilar canal (PSC)-sigmoid sinus (SS) distance, presigmoid dura- internal auditory canal (IAC)-PSC angle, and duration of surgery are predictors of complications. Specifically, a PSC-sigmoid sinus distance <11 mm, a dura presig-IAC-PSC angle <14 are associated with the highest risk of complications. CONCLUSION: Preoperative temporal bone CT scan can guide the surgeon through the narrowest areas of the surgical approach. Trautmann's triangle area and petro-clival angle reduction are challenging and can be faced with combined microscopic-endoscopic technique, and with optics angulation-rotation. The retrolabyrinthine approach can enable hearing preservation and minimal cerebellar retraction.

Expanding the spectrum on brain-heart interactions in cerebellopontine angle surgeries.

Lesions at the cerebellopontine angle (CP angle) are associated with various brain-heart interactions, which can include those from stimulation of the fifth cranial nerve along the scalp incision in a retrosigmoid suboccipital surgical approach. A 27-year-old male patient with recently diagnosed hypertension (on calcium channel blocker) underwent left CP angle lesion decompression. Transient episodes of bradycardia, hypotension, and bradypnea were observed from the skin incision onward, exacerbated during tumor manipulation. Most episodes subsided with cessation of the surgical stimulus while some required intervention. Postoperatively, blood pressure decreased below the pre-operative levels. Thus, trigeminocardiac reflex can occur as early as the skin incision even in a retrosigmoid approach due to stimulation of the mandibular division, when specific risk factors exist. Such episodes may serve as early warning signs for subsequent intraoperative occurrences. Brainstem compression can be a possible etiology of hypertension in young patients. It underscores the importance of considering brain-heart interactions in surgical interventions involving the CP angle.

Spontaneous Regression of a Large Vestibular Schwannoma: Is Nonoperative Management Reasonable?

Vestibular schwannomas (VSs) are the most common cerebellopontine tumors. The natural history of smaller-sized VSs (<30 mm) has been well-studied, leading to the recommendation of a "watch and wait" approach. However, large VSs (>30 mm) have not been extensively studied, mainly because of their rarity. As such, most patients are conventionally offered surgery which carries a significant risk of neurological morbidity. Here, we report a case of a giant VS (>40 mm) in a 30-year-old man who regressed spontaneously. He was lost to follow-up for 18 years and, upon re-presentation, the symptomatology drastically improved and repeat imaging demonstrated a marked reduction in tumor size. Referring to similar cases in other studies, we postulate that most large and giant VSs undergo a phase of growth and stasis, followed by regression due to shifts in the balance between tumorigenic and regressive factors. Taken together with emerging molecular data, further studies are required to better understand the history of large and giant VSs to shape more personalized treatment options. This potentially includes non-operative management as a tenable option.

Exoscopic Retrosigmoid Approach for an Anteromedial Tentorial Meningioma: 2D Operative Video.

We present a 2-dimensional operative video (Video 1) of a suboccipital retrosigmoid approach for an anteromedial tentorial meningioma with a specific focus on the use of a surgical exoscope. The patient is a 50-year-old woman who presented to emergency room with a 6-month history of nausea, dizziness, and gait imbalance secondary to a 2.5-cm homogenously enhancing mass originating from the anteromedial tentorium on the right side with associated brainstem compression. Retrosigmoid craniotomy was selected due to the favorable surgical corridor for resection and lower risk of cerebrospinal fluid leak, hearing loss, and seizures compared with other approaches.1-5 The patient consented to the procedure. Video 1 emphasizes the advantages of the exoscope compared with the microscope in optimizing surgeon efficiency, ergonomics, and comfort.6 The unique operating room setup associated with exoscope use is highlighted. The patient underwent uncomplicated gross total resection with a mild trochlear nerve palsy noted postoperatively that was resolved at follow-up.7.

Intracranial malignant peripheral nerve sheath tumor: A case report and comprehensive literature review.

Background: Malignant peripheral nerve sheath tumors (MPNSTs) are rare malignant soft-tissue sarcomas arising from peripheral nerves. Little data exist regarding MPNST originating intracranially. Here, we present a 7th/8th nerve complex MPNST, discuss the treatment strategy and patient outcome, and provide a comprehensive review of existing literature. Methods: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, PubMed and crossed references were queried, yielding 37 publications from 1952 to the present. Fifty-three cases of primary intracranial and extra-axial MPNST were identified. Results: We additionally report a 40-year-old female presented with acute onset dizziness and subsequent hearing loss with associated right-sided facial numbness. Magnetic resonance imaging revealed a 0.5 cm × 1.7 cm enhancing lesion within the right internal auditory canal extending into the cerebellopontine angle. The patient was initially treated with retro sigmoid craniotomy for tumor resection followed by a trans labyrinth approach for residual tumor resection. She completed adjuvant fractionated radiation therapy and underwent facial nerve transfer to restore complete hemifacial paralysis. The most common cranial nerves involved were V and VIII (43.4% each), with 66% of patients male and 34% female. The average age was 43.4 ± 17.4 years. The mean survival time for reported non-survivors after tissue diagnosis was 15 ± 4 months. Two-year survival for patients receiving gross total resection was 33.3% versus 22.8% with subtotal resection. Conclusion: MPNSTs comprise a group of highly aggressive neoplasms that rarely arise intracranially. Gross total surgical resection should be pursued when feasible.

Bevacizumab Treatment for Patients with NF2-Related Schwannomatosis: A Single Center Experience.

(1) Background: NF2-related schwannomatosis, characterized by the development of bilateral vestibular schwannomas, often necessitates varied treatment approaches. Bevacizumab, though widely utilized, demonstrates variable effectiveness on hearing and tumor growth. At the same time, (serious) adverse events have been frequently reported. (2) Methods: A single center retrospective study was conducted, on NF2-related schwannomatosis patients treated with bevacizumab from 2013 to 2023, with the aim to assess treatment-related and clinical outcomes. Outcomes of interest comprised hearing, radiologic response, symptoms, and adverse events. (3) Results: Seventeen patients received 7.5 mg/kg bevacizumab for 7.1 months. Following treatment, 40% of the patients experienced hearing improvement, 53%, stable hearing, and 7%, hearing loss. Vestibular schwannoma regression occurred in 31%, and 69% remained stable. Further symptomatic improvement was reported by 41%, stable symptoms by 47%, and worsened symptoms by 12%. Treatment discontinuation due to adverse events was observed in 29% of cases. Hypertension (82%) and fatigue (29%) were most frequently reported, with no occurrences of grade 4/5 toxicities. (4) Conclusion: Supporting previous studies, bevacizumab demonstrated positive effects on hearing, tumor control, and symptoms in NF2-related schwannomatosis, albeit with common adverse events. Therefore, careful consideration of an appropriate management strategy is warranted.

Outcomes of Trigeminal Ganglion Sparing Surgical Resection of Nonacoustic Cerebellopontine Angle Tumors Causing Trigeminal Neuralgia.

OBJECTIVE: Tumors may be responsible for up to 5% of trigeminal neuralgia cases. Predictors of long-term pain relief after surgical resection of various cerebellopontine angle tumor types are not well understood. Previous studies found that size and extent of resection predict long-term pain status, although resection of tumor involving the trigeminal ganglion may be associated with high morbidity. This study evaluated predictors of TN pain freedom after resection of a nonacoustic CPA tumor, with avoidance of any portion involving the TG. METHODS: In a retrospective cohort study, we evaluated clinical outcomes and complications after surgical resection of nonacoustic CPA tumors with purposeful avoidance of the TG causing trigeminal neuralgia. The primary outcome was pain-freedom. We performed logistic regression analyses to examine the relationship between pain-freedom at last follow-up and age, side of symptoms, preoperative symptom duration, tumor diameter, tumor type, and concurrent neurovascular compression (NVC). RESULTS: Of 18 patients with nonacoustic CPA tumors causing TN treated with surgical resection, 83.3% were pain-free at last follow-up (mean 44.6 months). Age (P = 0.12), side (P = 0.41), preoperative symptom duration (P = 0.85), tumor diameter (P = 0.29), tumor type (P = 0.37), and NVC presence (P = 0.075) were not associated with long-term pain freedom. CONCLUSIONS: This study provides additional evidence that various tumor types causing TN may safely undergo surgical resection and decompression of the trigeminal nerve to treat TN. This study presents a cohort of patients that underwent resection of a nonacoustic CPA tumor, with purposeful avoidance of the TG to minimize complications, demonstrating high rates of long-term pain freedom.

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.

Multicompartmental cystic trigeminal schwannoma as an uncommon differential diagnosis of cerebellopontine angle tumors.

Trigeminal schwannoma is the second most common intracranial schwannoma yet accounts for less than 0.5% intracranial tumors [1]. Cystic degeneration is uncommon. We would like to report a pathologically proven multicompartmental cystic trigeminal schwannoma in a young adult presenting with chronic headache. A literature review on the imaging features of trigeminal schwannoma is performed to assist radiologists in accurate disease localization and prioritizing differential diagnosis in challenging cases. Confident preoperative radiological diagnosis would directly affect management strategies.

Venous Sinus Thrombosis-Associated with Posterior Cranial Fossa Surgery. A Systematic Review and Meta-Analysis of Natural History, Risk Factors, Treatment, and Outcome.

BACKGROUND: Venous sinus thromboses (VSTs) are rare complications of neurosurgical procedures in the proximity of the dural sinuses. Surgery of the posterior cranial fossa (PCF) and particularly of the cerebellopontine angle (CPA) shows increased risk of VST. VST management is challenging because anticoagulant therapy must be balanced with the risk of postoperative bleeding. We performed a systematic review and meta-analysis to summarize the most important neuroradiologic and clinical aspects of VST after PCF/CPA surgery. METHODS: We performed a comprehensive literature search to identify articles reporting data on VST after PCF/CPA surgery. We selected only comparative studies providing adequate neuroimaging assessing VST and a control group. RESULTS: We included 13 articles reporting 1855 patients. VST occurred in 251/1855 cases (estimated incidence, 17.3%; 95% confidence interval [CI], 12.4%-22.2%). Only presigmoid approach (odds ratio [OR], 2.505; 95% CI, 1.161-5.404; P = 0.019) and intraoperative sinus injury (OR, 8.95; 95% CI, 3.43-23.34; P < 0.001) showed a significant association with VST. VST-related symptoms were reported in 12/251 patients with VST (pooled incidence, 3.1%; 95% CI, 1%-5.2%). In particular, we found a significantly increased OR of cerebrospinal fluid leak (OR, 3.197; 95% CI, 1.899-5.382; P < 0.001) and cerebrospinal fluid dynamic alterations in general (OR, 3.625; 95% CI, 2.370-5.543; P < 0.001). Indications for VST treatment were heterogeneous: 58/251 patients underwent antithrombotics, with 6 treatment-related bleedings. Recanalization overall occurred in 56.4% (95% CI, 40.6%-72.2%), with no significant difference between treated and untreated patients. However, untreated patients had a favorable outcome. CONCLUSIONS: VST is a relatively frequent complication after PCF/CPA surgery and a presigmoid approach and intraoperative sinus injury represent the most significant risk factors. However, the clinical course is generally benign, with no advantage of antithrombotic therapy.

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.

Paraganglioma at the cerebellopontine angle: A case report and review of literature.

Paragangliomas (PGLs) are rare neuroendocrine tumors. Sometimes, these tumors secrete excessive catecholamines, which results in the manifestations of various signs and symptoms, usually with a triad of hypertension, tachycardia, and headache. We report the case of a 42-year-old woman presenting with uncontrolled hypertension, right facial palsy, vomiting, and disturbed gait. Diagnosis for PGL was confirmed on postoperative histological examination of the excised mass and correlated with preoperative clinical and radiological findings. Tumor excision was done via a suboccipital craniotomy approach. Our case presents the typically severe features of a jugulotympanic PGL, but most importantly, it highlights the necessity of biochemical diagnosing, thorough probing of the causes of hypertension, and a multi-disciplinary approach in dealing with these tumors. Moreover, the case emphasizes necessitating the use of preoperative embolization in vascular tumors of the head and neck to avoid a hemorrhagic crisis during surgery. Unfortunately, due to a lack of adequate hospital funds, the surgeon had to proceed without preoperative embolization. Despite such a risk, the excision was a success.

Extra-axial cerebellopontine angle nodular medulloblastoma mimicking meningioma: a case report with literature review.

Introduction: Medulloblastoma, a highly malignant embryonal tumor predominantly found in the pediatric population, typically arises within the cerebellum. This case report holds particular importance due to the rarity of medulloblastoma within the cerebellopontine angle (CPA). The distinct anatomical challenge posed by the CPA complex neurovascular structures, along with the absence of pathognomonic clinical or radiographic features, highlights the unique diagnostic and management challenge of this case. Case presentation: A 5-year-old boy presented with mild, progressively worsening headaches on CT/MRI imaging, which revealed a solid mass in the left CPA. Radiologically, the lesion closely resembled a CPA meningioma. The patient underwent a left retrosigmoid suboccipital craniectomy, utilizing a modified park bench position and careful burrhole creation. Intraoperatively, the tumor exhibited well-defined margins, firm adherence to cranial nerves, and complex tissue characteristics. Postoperatively, histopathological analysis identified nodular medulloblastoma, WHO grade IV, with immunohistochemical markers confirming its subtype. Discussion: This case highlights the critical role of surgical intervention in addressing rare tumors, emphasizing the need for multidisciplinary collaboration in both diagnosis and management to achieve a favorable outcome. Uncommon tumor locations, such as the CPA, require tailored approaches, and the utilization of advanced diagnostic techniques, including immunohistochemistry, aids in accurate subtype classification. Conclusion: This case highlights the critical role of surgical intervention in addressing rare tumors, emphasizing the need for multidisciplinary collaboration in both diagnosis and management to achieve a favorable outcome.

A rare case of schwannomatosis with meningioma: a case report.

Introduction: Schwannomatosis is characterized by multiple schwannomas without vestibular schwannomas or any other stigmata of neurofibromatosis type 2 (NF2). Schwannomatosis is a rare disorder, with a reported incidence ranging from 1 in 40 000 to 1 in 1.7 million. Meningioma is also associated with schwannomatosis in around 5% of cases. Case presentation: We describe a case of a 20-year-old female presenting with progressive weakness of the right lower limb for 7 months with a tingling sensation and numbness of the same limb for 6 months and was found to have schwannomatosis with multiple spinal and right cerebellopontine angle (CPA) (9th/10th cranial nerve) schwannomas and left anterior cranial fossa meningioma. Discussion: Schwannomas in schwannomatosis are seen along the cranial, spinal, and peripheral nerves but not along the vestibular nerve, as is characteristically seen in NF2. The occurrence of meningiomas is about 5% in individuals with schwannomatosis, and the patient in our case also had an associated meningioma. The tumor was confirmed to be a schwannoma based on features on an MRI examination and histological examination. Conclusion: It is of great significance to identify the entire spectrum of the disease in a patient with schwannomatosis, and to differentiate it from related conditions in order to track and surgically manage the patient appropriately based on symptomatology and imaging findings.

Red flags alerting a posterior cranial fossa tumor from audiovestibular perspectives - a review.

BACKGROUND: There is no comprehensive and up-to-date overview of audiovestibular approach to the posterior fossa tumors in the literature. OBJECTIVE: This paper reviewed the literature relating to tumors at the posterior cranial fossa to find red flags alerting a posterior fossa lesion from audiovestibular perspectives. METHODS: This review was developed from articles published in those journals listed on the journal citation reports. Through the PubMed database, Embase, Google Scholar, and Cochrane library, 60 articles were finally obtained based on the PRISMA guidelines for reporting reviews. RESULTS: The presence of one red flag indicates a positive predictive value of 33% for detecting a posterior fossa lesion. Clinical features, namely, 1) mid-frequency sudden sensorineural hearing loss (SNHL), 2) bilateral sudden SNHL, and 3) rebound nystagmus may indicate a posterior fossa lesion, representing one, two, and three red flags, respectively. CONCLUSION: Those with 1) mid-frequency sudden SNHL, 2) bilateral sudden SNHL, and 3) rebound nystagmus trigger one, two, and three red flags, respectively, alerting clinicians the possibility of a posterior fossa lesion, which warrant MR imaging to exclude life-threatening or treatable conditions. SIGNIFICANCE: Patients with posterior fossa tumors may have potential life-threatening outcome.

Epidermoid cyst of the craniovertebral junction-A case report.

An epidermoid cyst is a benign tumor in many locations. The symptoms of an epidermoid cyst depend on its location. The brain or spine MRI can confirm the lesion. Removing total decompression is the first choice in treatment with a symptomatic cyst.