Neurofibromatosis Type 1-Associated Extracranial Vertebral Artery Aneurysm Complicated by Vertebral Arteriovenous Fistula After Rupture: Case Report and Literature Review.

BACKGROUND: Extracranial vertebral artery aneurysm related to neurofibromatosis type 1 (NF1) is rare. Aneurysmal rupture typically induces such symptoms as cervical hematoma, hemothorax, and hypotension. Here we report a case of ruptured extracranial vertebral artery aneurysm in a patient with NF1 who, rather than cervical hematoma, hemothorax, or hypotension, developed a vertebral arteriovenous fistula (AVF) after aneurysm rupture.

CASE DESCRIPTION: A 35-year-old woman with a family history of NF1 presented with sudden-onset right neck and shoulder pain. Computed tomography angiography showed a right extracranial vertebral artery aneurysm. She had neither a cervical hematoma nor hypotension; however, angiography showed an AVF secondary to aneurysmal rupture. The patient was treated with endovascular coil embolization to prevent re-rupture. Postoperatively, her right neck and shoulder pain improved, and she was discharged without further neurologic deficits.

CONCLUSIONS: This patient's clinical course suggests that if there is minimal bleeding from an NF1-associated ruptured extracranial vertebral artery aneurysm, then typical symptoms, such as cervical hematoma, hemothorax, and hypotension, may be absent. Thus, ruptured extracranial vertebral artery aneurysm should be considered in the differential diagnosis of patients with NF1 with sudden-onset radiculopathy, even in the absence of typical symptoms. The detection of a vertebral AVF provides a useful clue to the diagnosis of aneurysm rupture in such cases.