Presentation
Sudden headache radiating to the spine, nuchal rigidity, nausea, and vomiting. Rule out basilar dissection.
Patient Data
Non-contrast CT head
No evidence of intracranial bleed, infarct or mass effect. Preserved midline.
Cerebral sulci and ventricles and basal cisterns - normal width, shape, and location.
Symmetrically widened bilateral extra-axial frontoparietal space.
Sella turcica - normal size and appearance.
Osseous skull preserved.
Ocular globes, extraocular muscles, and retrobulbar fat normal.
Well-aerated paranasal sinuses, middle ears, and mastoid bones.
CT angiography head-neck
Malformation of convoluted dural vessels posterior and to the left of the cervical thecal sac, exerting pressure on it. The differential diagnosis is of spinal dural arteriovenous fistula (sdAVF) vs. arteriovenous malformation (AVM), with sdAVF more likely.
Cerebral arteries - normal location, position, and caliber, without any stenosis or irregularity.
Circle of Willis - no aneurysm over 2.5 mm in diameter identified.
No evidence of venous sinus thrombosis.
The arteries arising from the aortic arch and the branches of the cervical arteries are all patent; no evidence of arterial dissection.
Case Discussion
A young, healthy woman presented to the emergency room with a sudden headache that radiated to her spine, nuchal rigidity, nausea, and vomiting. She was afebrile.
Non-contrast CT head was normal, except for a substantially widened bilateral extra-axial frontoparietal space, possibly due to dehydration.
CTA head-neck revealed prominent convoluted dural veins that enhanced in the arterial phase, with several anomalous connections. Features were suggestive of a spinal dural arteriovenous fistula (sdAVF).
A perfunctory MRI-MRA was performed (not shown), after which the patient was taken to diagnostic catheterization:
Injection through both common carotid arteries and both vertebral arteries demonstrated several extradural fistulae from bilateral high dural branches of the vertebral arteries, as well as a fistula from branches of the ascending cervical artery on the right. The fistulae drain into a cluster of enlarged veins at the posterior part of the superior cervical canal, with superior drainage.
No aneurysm encountered.
In summary: ruptured superior cervical sdAVF.
She then went on to receive several therapeutic catheterizations.