Unusual case of hemangioblastoma of the cerebellopontine angle

Ruptured Medullary Hemangioblastoma Mimicking a Craniocervical Junction Dural Arteriovenous Fistula with a Pseudoaneurysm

Hemangioblastomas (HBMs) are rare vascular tumors commonly located in the posterior fossa of adults. A mid-50s patient presented with sudden unconsciousness. Computed tomography scans revealed acute hemorrhages around the posterior fossa, predominantly in the subarachnoid space. Digital subtraction angiography (DSA) revealed an 8-mm round lesion filled with contrast agent, fed by the C1 segmental artery of the left vertebral artery (VA), showing early venous drainage to the spinal cord and brainstem. Emergent embolization was attempted under suspicion of a ruptured dural arteriovenous fistula, resulting in parent artery occlusion due to feeder selection failure. Follow-up DSA after a month depicted a persistent aneurysm via collaterals from both VAs. Consequently, the decision was made to proceed with surgical intervention, leading to the resection of the lesion, confirming its diagnosis as a HBM through histological examination. This case underscores the potential for misdiagnosis when HBMs with an intratumoral shunt mimic vascular shunt lesions.

Usefulness of posterior transpetrosal approach for the large solid cerebellopontine angle hemangioblastoma fed from multiple blood supplies: A technical case report

Background

Extra-axial cerebellopontine angle (CPA) hemangioblastomas are rare clinical entity and surgical treatment is challenging due to the anatomical difficulties and multi-directional blood supplies. On the other hand, the risk of endovascular treatment for this disease has also been reported. Herein, we successfully applied a posterior transpetrosal approach to remove a large solid CPA hemangioblastoma without preoperative feeder embolization.

Case Description

A 65-year-old man presented with a complaint of diplopia during downward gaze. Magnetic resonance imaging revealed a solid tumor with homogeneous enhancement measuring about 35 mm at the left CPA, and the tumor compressed a left trochlear nerve. Cerebral angiography disclosed tumor-staining fed by both left superior cerebellar and left tentorial arteries. After the operation, the patient's trochlear nerve palsy improved dramatically.

Conclusion

This approach offers more optimal surgical working angle to the anteromedial part compared to the lateral suboccipital approach. In addition, the devascularization from the cerebellar parenchyma can be performed more reliably than the anterior transpetrosal approach. After all, this approach can be particularly useful when vascular-rich tumors receive blood supplies from multiple directions.

Successful preoperative embolization of a cystic-solid variant of cerebellopontine angle hemangioblastoma

Tumors of the cerebellopontine angle (CPA) represent an heterogeneous group which can arise extradural, intradural-extraaxial or intraaxial compartment. Hemangioblastomas of the cerebellopontine angle (CPA) are extremely rare. Computed tomography (CT) and magnetic resonance imaging (MRI) are often the gold-standard radiological imaging modalities used in characterizing the lesion's features, and its relationship with the surrounding structures. They are vascular lesions and may cause profuse bleeding intraoperatively, that is why angiography remains a crucial diagnostic and therapeutic tool, by reducing both the presurgical differential diagnosis, as well as the intraoperative bleeding by providing capability of embolization of this vascular tumor. We present the case of a 65 year old patient with a cystic-solid variety of HMB at the right CPA, which was successfully treated by a combination of an endovascular preoperative embolization and surgery without major complications or neurological deficits.

Cerebellopontine angle metastasis of a neuroendocrine tumor mimicking vestibular schwannoma: A case report

Background:

Neuroendocrine tumors (NETs) are uncommon neoplasms arising from neuroendocrine cells and are rarely associated with intracranial metastases.

Case Description:

We discuss the case of a 74-year-old woman with a right CPA tumor. She had a history of retroperitoneal NET, but was diagnosed with vestibular schwannoma due to a right-sided hearing loss and a right CPA tumor along the VII and VIII nerves. After a 3-year follow-up, she presented with repetitive vomiting, a 1-month history of gait instability, and a 3-month history of general fatigue. Brain imaging revealed tumor growth and edematous changes in the right cerebellum. She underwent retrosigmoid craniotomy and partial resection. Histopathological examination revealed metastatic NET. She underwent stereotactic radiosurgery for residual lesion and, at 11 months of follow-up, the lesion was confirmed to have shrunk on magnetic resonance imaging (MRI).

Conclusion:

This is the first case to report the natural course of cerebellopontine metastasis of a NET. The differential diagnosis of CPA tumors is diverse, and, in our case, we suspected a vestibular schwannoma because of the typical symptoms and imaging features. However, the tumor grew relatively faster than expected and showed intratumoral hemorrhage during the 3-year follow-up. Therefore, in patients with a history of a NET, a careful follow-up is advisable even for lesions highly suspected to be another benign tumor on MRI. Careful follow-up imaging and appropriate treatment strategies were useful to manage the brain metastasis. Although NETs metastasizing to the CPA are extremely rare, this possibility should be considered when patients with NETs have intracranial lesions.

Vertigo Related to Central Nervous System Disorders

PURPOSE OF REVIEW

This article provides an overview of the numerous causes of vertigo and dizziness that are due to central nervous system (CNS) pathology and guides clinicians in formulating a differential diagnosis and treating patients with CNS causes of vertigo.

RECENT FINDINGS

Specific autoimmune vestibulocerebellar syndromes may now be tested for, and this article discusses the antibodies known to cause such syndromes. Superficial siderosis can be more accurately diagnosed with imaging studies, and treatment using iron chelation has recently been studied but has not yet been established as an effective treatment. Central autonomic network damage in the brain can cause central orthostatic hypotension in some neurodegenerative diseases, and medication has been approved for treatment.

SUMMARY

CNS causes of vertigo are numerous and important for clinicians to recognize. Examination findings are still an extremely valuable way to diagnose central vertigo; therefore, learning how to differentiate central from peripheral vertigo based on examination is an important skill. CNS causes of vertigo often have available treatments.

Predominantly Solid Hemangioblastoma Presenting as an Extra-Axial Cerebellopontine Angle Lesion

Hemangioblastomas (HBs) are typically intra-axial, highly vascular tumors of the central nervous system and account for up to 2.5% of all intracranial tumors and up to 12% of posterior fossa neoplasms. Extra-axial HBs are rarely described in the literature. The radiological appearances of cerebellopontine angle (CPA) extra-axial HB can lead to a diagnostic conundrum as they may mimic the appearance of dural metastasis, vestibular schwannoma, or meningioma. Here, we describe a patient who presented with an extra-axial CPA HB and explore the literature of the condition.

Staged multi-modality treatment approaches for giant cerebellopontine angle hemangioblastomas

Giant hemangioblastomas (HBs) located in the cerebellopontine angle (CPA) present rare, high risk neurosurgical challenges. En bloc resection has been traditionally recommended for HBs, however this approach may pose unacceptable risk with giant tumors. Alternative treatment strategies have not been well described and the relevant literature is scant. This case review includes an illustrative patient with a giant, symptomatic CPA HB. It was felt that the neurovascular and tumor attributes were favorable for a multi-modality treatment strategy rather than circumferential dissection to remove this formidable tumor. A staged approach consisting of preoperative HB devascularization, debulking and piecemeal resection followed by radiosurgery for a small residuum produced an excellent clinical outcome. Variations of this unconventional multi-modality strategy may reduce the perioperative morbidity of carefully selected patients with giant CPA HBs. A thorough literature review is provided.