Large vertebral artery pseudoaneurysm masquerading as a schwannoma: illustrative case.

Background: Extracranial vertebral aneurysms or pseudoaneurysms are rare and result primarily from trauma. Large pseudoaneurysms can masquerade as mass lesions, making it challenging to identify the correct diagnosis.

Observations: This is a case report in which a large vertebral pseudoaneurysm posed as a schwannoma and biopsy was attempted. It was later identified as a vascular lesion and treated appropriately with no complications.

Lessons: Vascular etiologies should always be included in the differential diagnosis of spine and nerve pathologies especially lesions that are in the vicinity of major vascular channels such as the transverse foramina of the cervical spine.