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.