Diagnosis

If you have signs or symptoms of a dural arteriovenous fistula (dAVF), your doctor may recommend that you undergo diagnostic tests, including:

Initial imaging

Initial evaluation typically includes cross-sectional imagery from noncontrast head computerized tomography (CT) and magnetic resonance imaging (MRI).

CT head scans can show fluid buildup caused by heightened cortical vein blood pressure as well as actual bleeding, which may be caused by a dAVF but occur elsewhere in the brain's venous system.

MRIs can establish the shape and extent of a dAVF, detect any micro-hemorrhages (very small bleed locations), and determine the impact of any abnormal blood vessel structures related to the fistula itself.

Angiography

Catheter-based cerebral angiography (also known as digital subtraction angiography) is still the most reliable and definitive tool on dAVF diagnosis. It's essential for defining:

• How many fistulae exist and where
• Anatomy of the external carotid arteries and any branches between them and the dura
• Fistula blood vessels' structure
• Whether cardiovascular disease is also present
• How much narrowing or blockage has occurred in the dural sinus
• Whether any affected veins are dilated and to what extent

Superselective angiography may also be required to identify the area of convergence of the feeding dural arteries and the origin of the draining vein.