Imaging Studies
Direct carotid-cavernous sinus fistulae
Computed tomography (CT) scan, magnetic resonance imaging (MRI), and orbital echography often help to confirm the diagnosis, demonstrating extraocular muscle enlargement, dilation of one or both superior ophthalmic veins, and enlargement of the affected cavernous sinus. [2]
Dural carotid-cavernous sinus fistulae
CT scan, MRI, and orbital echography may help to confirm the diagnosis.
All carotid-cavernous sinus fistulae
The definitive diagnostic test is cerebral arteriography with selective catheterization of the internal and external carotid arteries on both sides, so that all arterial contributions to the fistulae can be visualized.
Intra-arterial subtraction angiography is generally the preferred technique.
Other Tests
Tonometry (preferably with a pneumotonometer) usually demonstrates greater pulse amplitude on the side of the lesion.
