Intracranial trigeminal schwannoma

Imaging of the skull base and orbital tumors

The skull base and orbit have complicated anatomical structures where various tumors can occur. The tumor may present with neurological symptoms; however, its diagnosis is clinically difficult owing to accessibility issues. Therefore, diagnostic imaging is crucial in assessing tumors in the skull base and orbit and guiding subsequent management. Notably, some tumors have a predilection for a specific site of origin, and identifying the site of origin on imaging can help narrow the differential diagnosis. At the skull base, chordomas typically occur in the clivus, chondrosarcomas in the paramedian areas, paragangliomas in the jugular foramen, neurogenic tumors, and perineural spread in the neural foramen. Among orbital tumors, cavernous hemangiomas usually occur in the intraconal space, and pleomorphic adenomas and adenoid cystic carcinomas occur in the lacrimal glands. Some skull base and orbital tumors exhibit distinctive imaging features. Chordomas and chondrosarcomas of the skull base show high signal intensities on T2-weighted images, with chondrosarcomas often displaying cartilaginous calcifications. Paragangliomas are characterized by their hypervascular nature. In the orbit, cavernous hemangiomas and pleomorphic adenomas present unique dynamic patterns. Immunoglobulin G4-related disease forms lesions along the nerves. Identifying the tumor origin and its imaging characteristics can help narrow the differential diagnosis of skull base and orbital tumors.

Preoperative Vascular and Cranial Nerve Imaging in Skull Base Tumors

Skull base tumors such as meningiomas and schwannomas are often pathologically benign. However, surgery for these tumors poses significant challenges because of their proximity to critical structures such as the brainstem, cerebral arteries, veins, and cranial nerves. These structures are compressed or encased by the tumor as they grow, increasing the risk of unintended injury to these structures, which can potentially lead to severe neurological deficits. Preoperative imaging is crucial for assessing the tumor size, location, and its relationship with adjacent vital structures. This study reviews advanced imaging techniques that allow detailed visualization of vascular structures and cranial nerves. Contrast-enhanced computed tomography and digital subtraction angiography are optimal for evaluating vascular structures, whereas magnetic resonance imaging (MRI) with high-resolution T2-weighted images and diffusion tensor imaging are optimal for evaluating cranial nerves. These methods help surgeons plan tumor resection strategies, including surgical approaches, more precisely. An accurate preoperative assessment can contribute to safe tumor resection and preserve neurological function. Additionally, we report the MRI contrast defect sign in skull base meningiomas, which suggests cranial nerve penetration through the tumor. This is an essential finding for inferring the course of cranial nerves completely encased within the tumor. These preoperative imaging techniques have the potential to improve the outcomes of patients with skull base tumors. Furthermore, this study highlights the importance of multimodal imaging approaches and discusses future directions for imaging technology that could further develop preoperative surgical simulations and improve the quality of complex skull base tumor surgeries.

Microsurgical Resection of Trigeminal Schwannoma Through Transorbital Approach: 2-Dimensional Operative Video

We present the case of an asymptomatic 34-year-old woman who was found to have an incidental left trigeminal schwannoma.1,2 Owing to the rapid increase in size on imaging, an atypical finding for this type of lesion,3 as well as the risk of cranial nerve involvement and need for tissue diagnosis, the patient underwent a microsurgical left transorbital approach with lateral orbitotomy to resect the lesion.4,5 Piecemeal resection was performed, and the internal contents of the cavernous sinus were preserved. Ultimately, gross total resection was achieved with no residual disease identified on postoperative imaging. No new neurologic deficits were noted after surgery. The technical considerations for the transorbital approach and the literature review on the outcomes for middle fossa lesions accessed by a lateral orbitotomy are reviewed.6-10 The patient consented to the procedure and to the publication of her images. Institutional Review Board approval was deemed unnecessary due to the retrospective, case-report nature of this work.

Pediatric Hemispheric High-Grade Gliomas and H3.3-G34 Mutation: A Review of the Literature on Biological Features and New Therapeutic Strategies

Pediatric high-grade glioma (pHGG) encompasses a wide range of gliomas with different genomic, epigenomic, and transcriptomic features. Almost 50% of pHGGs present a mutation in genes coding for histone 3, including the subtype harboring the H3.3-G34 mutation. In this context, histone mutations are frequently associated with mutations in TP53 and ATRX, along with PDGFRA and NOTCH2NL amplifications. Moreover, the H3.3-G34 histone mutation induces epigenetic changes in immune-related genes and exerts modulatory functions on the microenvironment. Also, the functionality of the blood-brain barrier (BBB) has an impact on treatment response. The prognosis remains poor with conventional treatments, thus eliciting the investigation of additional and alternative therapies. Promising molecular targets include PDGFRA amplification, BRAF mutation, EGFR amplification, NF1 loss, and IDH mutation. Considering that pHGGs harboring the H3.3-G34R mutation appear to be more susceptible to immunotherapies (ITs), different options have been recently explored, including immune checkpoint inhibitors, antibody mediated IT, and Car-T cells. This review aims to summarize the knowledge concerning cancer biology and cancer-immune cell interaction in this set of pediatric gliomas, with a focus on possible therapeutic options.

Clinical characteristics and outcomes after trigeminal schwannoma resection: a multi-institutional experience

Given their rarity, the clinical course of patients undergoing trigeminal schwannoma (TS) resection remains understudied. The objective of this study is to describe clinical characteristics and outcomes in patients undergoing surgical resection for TS in a multi-institutional cohort. This is a retrospective study of patients undergoing TS resection at two institutions between 2004 and 2022. Patient, radiographic, and clinical characteristics were reviewed and analyzed with standard statistical methods. Thirty patients were included. The median patient age was 43 (IQR: 35-52) years, and 14 (47%) patients were female. Median clinical and radiographic follow-ups were 43 (IQR: 20-81) and 47 (IQR: 27-97) months respectively. The most common presenting symptoms were trigeminal hypesthesia (57%) and headaches (30%), diplopia (30%), and ataxia/cerebellar signs (30%). The median maximum tumor diameter was 3.3 (IQR: 2.5-5.4) cm. Most tumors were Samii type C (50%) and mixed cystic-solid (63%). Surgical approaches included endoscopic endonasal (33%), supratentorial (30%), combined/staged (20%), infratentorial (10%), and anterior petrosal (7%) approaches. Gross-total resection was achieved in 16 (53%) patients. Radiographic tumor recurrence was noted in four patients at a median of 79 (range 5-152) months. Twenty-six (87%) patients reported improvements in at least one symptom by last follow-up. The most common perioperative complication was new cranial nerve deficit, with 17% of patients having a transient deficit and 10% having a permanent cranial nerve deficit. Surgical resection of TS showed good progression-free survival and symptom improvement, but was associated with cranial nerve deficits.

Treating Trigeminal Schwannoma through a Transorbital Approach: A Systematic Review

Background: Trigeminal schwannomas (TSs) are uncommon tumors found along any segment of the fifth cranial nerve (CN V). Typically located at the skull base, these benign tumors carry substantial morbidity due to the extent of traditional surgical methods. Minimally invasive endoscopic surgery such as the endoscopic transorbital approach (ETOA) presents promising new avenues for treatment, with the transorbital approach emerging as a potentially successful alternative. Methods: This review systematically assesses the application of the ETOA in treating TSs. PubMed, Ovid MEDLINE, and Embase were thoroughly searched for articles detailing the use of the ETOA in clinical case studies. The outcomes of interest encompassed epidemiological profiling, surgical results, and complication rates. Results: This study included 70 patients with TSs (from six studies), with 22 males (31.4%) and 58 females (68.6%). Patients averaged 55 years and were monitored for around 16.4 months (on average). In most tumors, the middle cranial fossa was involved to some degree. The majority (87.2%) were large (3-6 cm) and underwent gross total resection (GTR) or near-total resection in 87.2% of patients. Preoperatively, sensory alterations were common, along with proptosis, neuropathic pain, and diplopia. Postoperatively, complications included ptosis, diplopia, sensory impairment, corneal keratopathy, masticatory difficulty, and neuralgia. The pure ETOA was the primary surgical technique used in 90% of cases, with no recurrence observed during the follow-up period. Conclusions: Using the ETOA to treat TSs demonstrated an oncologic control rate of 87.2%. Postoperative complications including ptosis, diplopia, and sensory disturbances have been observed, but careful monitoring and management can mitigate these problems. The ETOA emerges as a viable surgical option, especially for tumors involving the middle cranial fossa, capable of adapting to individual patient needs and demonstrating efficacy in TS management.

Preservation of cranial nerve function in large and giant trigeminal schwannoma resection: a case series

BACKGROUND

Trigeminal schwannomas (TSs) are intracranial tumors that can cause significant brainstem compression. TS resection can be challenging because of the risk of new neurologic and cranial nerve deficits, especially with large (≥ 3 cm) or giant (≥ 4 cm) TSs. As prior surgical series include TSs of all sizes, we herein present our clinical experience treating large and giant TSs via microsurgical resection.

METHODS

This was a retrospective, single-surgeon case series of adult patients with large or giant TSs treated with microsurgery in 2012-2023.

RESULTS

Seven patients underwent microsurgical resection for TSs (1 large, 6 giant; 4 males; mean age 39 ± 14 years). Tumors were classified as type M (middle fossa in the interdural space; 1 case, 14%), type ME (middle fossa with extracranial extension; 3 cases, 43%), type MP (middle and posterior fossae; 2 cases, 29%), or type MPE (middle/posterior fossae and extracranial space; 1 case, 14%). Six patients were treated with a frontotemporal approach (combined with transmastoid craniotomy in the same sitting in one patient and a delayed transmaxillary approach in another), and one patient was treated using an orbitofrontotemporal approach. Gross total resection was achieved in 5 cases (2 near-total resections). Five patients had preoperative facial numbness, and 6 had immediate postoperative facial numbness, including two with worsened or new symptoms. Two patients (28%) demonstrated new non-trigeminal cranial nerve deficits over mean follow-up of 22 months. Overall, 80% of patients with preoperative facial numbness and 83% with facial numbness at any point experienced improvement or resolution during their postoperative course. All patients with preoperative or new postoperative non-trigeminal tumor-related cranial nerve deficits (4/4) experienced improvement or resolution on follow-up. One patient experienced tumor recurrence that has been managed conservatively.

CONCLUSIONS

Microsurgical resection of large or giant TSs can be performed with low morbidity and excellent long-term cranial nerve function.

Extra-axial cranial nerve enhancement: a pattern-based approach

Cranial nerve enhancement is a common and challenging MRI finding that requires a meticulous and systematic evaluation to identify the correct diagnosis. Literature mainly describes the various pathologies with the associated clinic-radiological characteristics, while the radiologist often needs a reverse approach that starts from the radiological findings to reach the diagnosis. Therefore, our aim is to provide a new and practical pattern-based approach to cranial nerve enhancement, which starts from the radiological findings and follows pattern-driven pipelines to navigate through multiple differential diagnoses, guiding the radiologist to reach the proper diagnosis. Firstly, we reviewed the literature and identified four patterns to categorize the main pathologies presenting with cranial nerve enhancement: unilateral linear pattern, bilateral linear pattern, unilateral thickened pattern, and bilateral thickened pattern. For each pattern, we describe the underlying pathogenic origin, and the main radiological features are displayed through high-quality MRI images and illustrative panels. A suggested MRI protocol for studying cranial nerve enhancement is also provided. In conclusion, our approach for cranial nerve enhancement aims to be an easy tool immediately applicable to clinical practice for converting challenging findings into specific pathological patterns.

Trigeminal Schwannoma - Case Report of a Rare Tumour

Schwannomas are benign nerve tumours arising from the Schwann cells. Approximately 25-45% of schwannomas occurs in the head and neck region. Majority of schwannomas in the head and neck region arise from the vagus nerve. Trigeminal schwannomas account for about 0.2% of all intracranial tumours. Trigeminal schwannomas can originate from any section of the fifth cranial nerve, from the root to the distal extracranial branches, but majority develops from the Gasserian ganglion, usually growing in the middle cranium. Most common presenting symptom is facial pain. MRI is the imaging modality of choice and CT scan usually serves as a supplementary imaging especially for skull base tumours. 47 year old male patient presented to the outpatient department with complains of swelling over the left side of palate. Contrast enhanced CT scan demonstrated a large bilobed heterogeneously enhancing soft tissue lesion in the left infratemporal fossa with widened foramen ovale and extension of lesion into the Meckel's cave, larger contiguous component extending into ramus of mandible. MRI scan showed a large lobulated mass in the left masticator space with intracranial extension. Biopsy of the lesion was suggestive of schwannoma. The patient underwent left composite resection with dural repair and free flap reconstruction. Post operatively, on day 5 he developed features of meningitis for which he was treated conservatively and later discharged in stable condition. Trigeminal schwannomas are rare tumours with very low chance of malignant transformation which commonly presents with facial pain. MRI is the imaging modality of choice. Complete surgical excision is the treatment of choice.

Two-Stage Resection of a Giant Trigeminal Schwannoma in a Non-Neurofibromatosis Type 2 Pediatric Patient: A Case Report, Systematic Review, and Intraoperative Video

BACKGROUND

Trigeminal schwannoma is an uncommon tumor in pediatric patients. Several surgical approaches have been described in the literature.

METHODS

The case of an 11-year-old boy with a giant dumbbell-shaped trigeminal schwannoma removed through a 2-stage approach was presented with an intraoperative video. Using PubMed and Scopus, the literature on trigeminal schwannoma in pediatric patients was searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

RESULTS

The search strategy yielded 312 titles, of which 13 were included in the review. Cases of trigeminal schwannoma were described, with a highly variable clinical presentation and anatomical arrangement in cranial fossae. Two-stage approaches were reported, although most studies described single-stage approaches. Common postoperative outcomes were a range of disturbances of cranial nerve V.

CONCLUSIONS

The surgical approach varies based on the tumor conformation. However, a 2-stage pterional subtemporal and semisitting retrosigmoid approach is a safe, practical, and effective strategy for the removal of dumbbell-shaped trigeminal schwannoma in a pediatric patient.

Three-Dimensional Constructive Interference in Steady State (3D CISS) Imaging and Clinical Applications in Brain Pathology

Three-dimensional constructive interference in steady state (3D CISS) is a steady-state gradient-echo sequence in magnetic resonance imaging (MRI) that has been used in an increasing number of applications in the study of brain disease in recent years. Owing to the very high spatial resolution, the strong hyperintensity of the cerebrospinal fluid signal and the high contrast-to-noise ratio, 3D CISS can be employed in a wide range of scenarios, ranging from the traditional study of cranial nerves, the ventricular system, the subarachnoid cisterns and related pathology to more recently discussed applications, such as the fundamental role it can assume in the setting of acute ischemic stroke, vascular malformations, infections and several brain tumors. In this review, after briefly summarizing its fundamental physical principles, we examine in detail the various applications of 3D CISS in brain imaging, providing numerous representative cases, so as to help radiologists improve its use in imaging protocols in daily clinical practice.

Management of non-vestibular schwannomas in adult patients: a systematic review and consensus statement on behalf of the EANS skull base section Part II: Trigeminal and facial nerve schwannomas (CN V, VII)

BACKGROUND

Non-vestibular schwannomas are relatively rare, with trigeminal and jugular foramen schwannomas being the most common. This is a heterogenous group which requires detailed investigation and careful consideration to management strategy. The optimal management for these tumours remains unclear and there are several controversies. The aim of this paper is to provide insight into the main principles defining management and surgical strategy, in order to formulate a series of recommendations.

METHODS

A task force was created by the EANS skull base section committee along with its members and other renowned experts in the field to generate recommendations for the surgical management of these tumours on a European perspective. To achieve this, the task force performed an extensive systematic review in this field and had discussions within the group. This article is the second of a three-part series describing non-vestibular schwannomas (V, VII).

RESULTS

A summary of literature evidence was proposed after discussion within the EANS skull base section. The constituted task force dealt with the practice patterns that exist with respect to pre-operative radiological investigations, ophthalmological assessments, optimal surgical and radiotherapy strategies, and follow-up management.

CONCLUSION

This article represents the consensually derived opinion of the task force with respect to the treatment of trigeminal and facial schwannoma. The aim of treatment is maximal safe resection with preservation of function. Careful thought is required to select the appropriate surgical approach. Most middle fossa trigeminal schwannoma tumours can be safely accessed by a subtemporal extradural middle fossa approach. The treatment of facial nerve schwannoma remains controversial.

Double-Stage Complete Removal of Dumbbell-Shaped Trigeminal Schwannoma: 3-Dimensional Operative Video

Intracranial trigeminal schwannomas are rare tumors.1-4 The aim of this 3-dimensional operative video is to present a double stage complete removal of a dumbbell-shaped trigeminal schwannoma. This is a 25-yr-old male with headaches, diplopia, and facial pain. The MRI shows a big tumor located at the level of the cerebellopontine angle, petroclival region, and middle fossa. Because of the size of the tumor and its growth within the cerebellopontine angle, we decided to operate the patient in two stages. For the first surgery, the patient was in a semi-sitting position, and a retrosigmoid approach was performed. The second surgery was performed 2 mo after the first operation in a supine position for a pretemporal transzygomatic approach. The pathological study was reported as a schwannoma, and the histological findings were spindle cell lesion with a storiform pattern and histiocytes. The patient evolved without neurological deficit after the surgeries, and the postoperative MRI shows a complete resection of the tumor. The patient gave the consent to use the images and surgical video. Preoperative imaging plays an important role in diagnosis and surgical planning.3-6 For these cases of trigeminal schwannomas with a large extension in the posterior fossa and middle fossa, we believe that the most prudent thing is to perform the surgery in 2 stages.3.

Ancient Schwannoma affecting the intracranial portion of the trigeminal nerve: A case report

Background:

Ancient trigeminal schwannomas are extremely uncommon benign tumors. Such tumors are longstanding, slow growing and may demonstrate seemingly malignant features irrespective of its benign nature. The tumor may involve the trigeminal nerve root, the trigeminal ganglion, or any of its peripheral branches. Its clinical presentation may include trigeminal neuralgia, blurry vision, diplopia, or even seizures. Surgical excision is the mainstay of treatment with definite diagnosis only by histopathology.

Case Description:

We described a case of a 35-year-old female presenting with recurrent episodes of generalized seizure and left-sided weakness. Brain imaging showed a right temporal space occupying lesion. Results of histopathology were consistent with trigeminal schwannoma associated with ancient histopathological changes. Complete tumor excision was achieved by a two-stage craniotomy, which led to the patient’s condition to dramatically improve.

Conclusion:

Ancient trigeminal schwannomas are easily diagnosed through histopathology and result in favorable clinical outcomes after total microscopic surgical excision. A high suspicion index of ancient schwannoma diagnosis should be derived from the patient’s presenting clinical picture and the classical findings derived from neuroimaging.

Surgical Management of Multifocal Trigeminal Schwannomas

BACKGROUND

Isolated trigeminal schwannomas occur in 0.07% to 0.3% of intracranial tumors and account for 0.8% to 8% of intracranial schwannomas and 1/3 of Meckel cave tumors. The presence of multisegmental schwannoma is rare, resulting in a limited understanding of its optimal management.

OBJECTIVE

To describe potential surgical options to manage this rare entity.

METHODS

A 2-institution retrospective review of all patients with pathologically confirmed trigeminal schwannoma managed with resection from January 2009 through January 2019 was conducted. A manual chart review was performed to verify patients' inclusion and collect data about age, sex, tumor size, tumor site, treatment modality, surgical approach, complications, and follow-up duration and status.

RESULTS

A total of 4 patients (age range 12-50 yr) who underwent a variety of cranial and orbitocranial approaches for tumor resection were identified. Patients achieved good outcomes with improvement of visual outcomes. One case of infection and 1 case of partial tumor recurrence requiring reresection were identified.

CONCLUSION

Multisegmental trigeminal schwannoma is a rare and unique entity, often associated with trigeminal schwannomatosis. Interdisciplinary management has been shown to be the most effective method for improving patient outcomes with these complex and poorly understood diseases.

Trigeminal schwannoma presenting with malocclusion: A case report and review of the literature

BACKGROUND

Trigeminal schwannomas are rare tumors of the trigeminal nerve. Depending on the location, from which they arise along the trigeminal nerve, these tumors can present with a variety of symptoms that include, but are not limited to, changes in facial sensation, weakness of the masticatory muscles, and facial pain.

CASE DESCRIPTION

We present a case of a 16-year-old boy with an atypical presentation of a large trigeminal schwannoma: painless malocclusion and unilateral masticatory weakness. This case is the first documented instance; to the best of our knowledge, in which a trigeminal schwannoma has led to underbite malocclusion; it is the 19th documented case of unilateral trigeminal motor neuropathy of any etiology. We discuss this case as a unique presentation of this pathology, and the relevant anatomy implicated in clinical examination aid in further understanding trigeminal nerve pathology.

CONCLUSION

We believe our patient's underbite malocclusion occurred secondary to his trigeminal schwannoma, resulting in associated atrophy and weakness of the muscles innervated by the mandibular branch of the trigeminal nerve. Furthermore, understanding the trigeminal nerve anatomy is crucial in localizing lesions of the trigeminal nerve.

Trigeminal Ganglion Metastasis of Renal Clear Cell Carcinoma: Cases Report and Review of the Literature

BACKGROUND

The trigeminal ganglion is an atypical site for metastasis, especially for renal clear cell carcinoma.

CASE DESCRIPTION

We report 2 clinical cases of a 66-year-old man and a 58-year-old man with trigeminal symptoms. Both patients had a history of renal clear cell (RCC) that was considered to be cured at 6 and 9 years, respectively. Brain magnetic resonance imaging (MRI) showed a trigeminal ganglion lesion with increased gadolinium enhancement associated with petrous apex erosion. The main diagnostic hypothesis based on MRI was trigeminal schwannoma for both patients. One patient underwent subtotal removal, the other a biopsy. Histologic examinations resulted in the diagnosis of RCC metastasis. Body computed tomography revealed pancreatic metastasis for both but no renal recurrence. The patients were treated by local radiotherapy, and 1 of the patients had associated chemotherapy. We added to these clinical cases a literature review of skull base metastasis of RCC. Trigeminal ganglion metastasis of RCC is very rare and can persist until 10 years after the first RCC diagnosis. It seems that the best treatment is surgical removal. To date, the role of local radiotherapy is not demonstrated, and the prognosis seems to be poor.

CONCLUSIONS

In the case of trigeminal symptoms, rapid tumoral growth on brain MRI, or a history of RCC, we think that a body computed tomography should be performed, and surgery should be considered.

Imaging of cranial nerves: a pictorial overview

The human body has 12 pairs of cranial nerves that control motor and sensory functions of the head and neck. The anatomy of cranial nerves is complex and its knowledge is crucial to detect pathological alterations in case of nervous disorders. Therefore, it is necessary to know the most frequent pathologies that may involve cranial nerves and recognize their typical characteristics of imaging. Cranial nerve dysfunctions may be the result of pathological processes of the cranial nerve itself or be related to tumors, inflammation, infectious processes, or traumatic injuries of adjacent structures. Magnetic resonance imaging (MRI) is considered the gold standard in the study of the cranial nerves. Computed tomography (CT) allows, usually, an indirect view of the nerve and is useful to demonstrate the intraosseous segments of cranial nerves, the foramina through which they exit skull base and their pathologic changes. The article is a complete pictorial overview of the imaging of cranial nerves, with anatomic and pathologic descriptions and great attention to illustrative depiction. We believe that it could be a useful guide for radiologists and neuroradiologists to review the anatomy and the most important pathologies that involve cranial nerves and their differential diagnosis.

Microsurgical Management of Trigeminal Schwannoma: Cohort Analysis and Systematic Review

Background  Trigeminal schwannomas are benign tumors with a predilection for women between 40 and 60 years of age and account for less than 0.5% of all intracranial tumors. Clinical presentation depends on size and location, and typical symptoms are ipsilateral hypesthesia, headache, and facial pain. Clinical features and imaging usually make the Diagnosis. Methods  A retrospective cohort analysis of 14 patients treated at our institution between January 1999 and October 2016 was performed, with a critical and systematic review of data from the literature, focusing on articles published over the same period. Results  Fourteen patients were included in our series comprised of mostly women with a mean age of 40 years. Lesion size ranged from 3 to 6.5 cm (mean 4.6 cm). Clinical status of patients was evaluated and also rated based on the Karnofsky Perfomance Scale with values greater than 90% found in all patients pre and postoperatively. Surgery was our treatment of choice, and gross total resection was achieved in 71% of patients. Associated morbidity was high at 57%, predominantly from cranial nerve palsy, and no deaths were encountered. Conclusions  Microsurgery is a suitable treatment for large symptomatic trigeminal schwannomas, achieving good local control rates over the observation period at acceptable morbidity. Therefore, microsurgery appears to a suitable option. During the study period, a significant evolution in the availability of treatment methods occurred. Radiosurgery emerged as an alternative treatment for unresectable lesions. A comprehensive review of the available literature was performed, and results were compared according to treatment modality.

Multicompartmental Trigeminal Schwannomas: Dumbbell Tumors Revisited

Multicompartmental trigeminal schwannomas (MTSs) are a rare and complex but treatable group of tumors. Herein, we describe the clinicoradiologic presentation of two patients with MTS. The two illustrated distinct case reports highlight the role of imaging and the outcome of two different types of MTS. The Discussion summarizes the literature to date, which will help the reader diagnose these tumors in a timely manner and manage them appropriately.