Intracranial Hemorrhage from Dural Arteriovenous Fistulas: What Can We Find with CT Angiography?

Abstract

(1) Background: Dural arteriovenous fistulas (DAVF) represent a rare acquired intracranial vascular malformation, with a variety of clinical signs and symptoms, which make their diagnosis difficult. Intracranial hemorrhage is one of the most serious clinical manifestations. In this paper the authors' goal was to verify the accuracy and utility of contrast-enhanced brain CT angiography (CTA) for the identification and the characterization of dural arteriovenous fistulas (DAVFs) in patients who presented with brain hemorrhage compared to 3D digital subtraction angiography (3D DSA); (2) a retrospective study of 26 patients with DAVFs who presented with intracranial hemorrhage to our institution was performed. The information reviewed included clinical presentation, location and size of hemorrhage, brain CTA and 3D DSA findings; (3) results: 61% (16/26) of DAVFs were identified by CTA. The vast majority of patients were male (69%, 18/26) and the most common presenting symptom was sudden onset headache. All DAVFs had cortical venous drainage and about one-third were associated with a venous varix. The most common location was tentorial (73%, 19/26); (4) conclusions: CTA can represent a valid alternative diagnostic method to 3D DSA for the study of DAVF in the initial and preliminary diagnostic approach, especially in emergency situations. In fact, it represents a fast, inexpensive, non-invasive and above all, easily accessible and available diagnostic technique, unlike DSA or MRI, allowing to provide information necessary for the identification, classification and treatment planning of DAVFs.

Keywords: 3D digital subtraction angiography (DSA); brain CT angiography (CTA); dural arteriovenous fistulas (DAVFs).

Figure 1

(a) Axial 3-mm-slab MIP from CTA. Dilated engorged cortical veins with a prominent dilated vein (blue arrow) in a patient with a right tentorial DAVF (b,c) DSA, arterial phase, right vertebral artery injection in antero-posterior (b) and in oblique projection (c) in the same patient 1 shows dilated arterial feeders from right superior cerebellar artery (red arrow) and engorged cortical veins, that correlate with the angio CT findings.

Figure 2

(a) Sagittal 3-mm-slab MIP from CTA. Dilated engorged cortical veins with a prominent dilated vein (blue arrow) in the patient 1 with a right tentorial DAVF with abnormal early opacification of the straight sinus (orange arrow), showing arterial contrast intensity, differently from the other intracranial venous sinus (b) DSA, arterial phase, right vertebral artery injection in the sagittal projection in the same patient 1 shows arterial feeders from the right superior cerebellar artery, enlarged cortical veins with a prominent vein (blue arrow) and reflux in the straight sinus (orange arrow), the correlate of the arterial contrast intensity shown on CTA in (a), proving the arterialization of venous structures. The other venous sinus did not show the same attenuation.