Radiologic Assessment of Brain Arteriovenous Malformations: What Clinicians Need to Know

Abstract

Brain arteriovenous malformations (AVMs) are abnormal vascular connections within the brain that are presumably congenital in nature. There are several subgroups, the most common being glomerular type brain AVMs, with fistulous type AVMs being less common. A brain AVM may also be a part of more extensive disease (eg, cerebrofacial arteriovenous metameric syndrome). When intracranial pathologic vessels are encountered at cross-sectional imaging, other diagnoses must also be considered, including large developmental venous anomalies, malignant dural arteriovenous fistulas, and moyamoya disease, since these entities are known to have different natural histories and require different treatment options. Several imaging findings in brain AVMs have an impact on decision making with respect to clinical management; the most important are those known to be associated with risk of future hemorrhage, including evidence of previous hemorrhage, intranidal aneurysms, venous stenosis, deep venous drainage, and deep location of the nidus. Other imaging findings that should be included in the radiology report are secondary effects caused by brain AVMs that may lead to nonhemorrhagic neurologic deficits, such as venous congestion, gliosis, hydrocephalus, or arterial steal.

Noninvasive Evaluation of Cerebral Arteriovenous Malformations by 4D-MRA for Preoperative Planning and Postoperative Follow-Up in 56 Patients: Comparison with DSA and Intraoperative Findings

“…26 Image-update rates in DSA in our study ranged from 2 to 8 frames per second. At the expense of a higher patient dose, even higher frame rates are possible with modern conventional angiography units.…”

Brain Arterio-Venous Malformations Presenting with Seizures and Diagnosed on CT Scan: A Case Report

“…The picture (cross sectional CT or MRI) in large developmental venous anomalies is that of enhancement of the dilated medullary veins which is described as a caput medusa or an inverted umbrella. In dural arterio-venous fistulas, dilated cortical veins which manifest as abnormal enhancing tubular structures or flow voids within the cortical sulci with no true nidus within the brain parenchyma are seen and in Moyamoya disease, there is the presence of tiny flow voids arising from the basal cisterns and extending into the basal ganglia or the thalamus with no true nidus embedded within the brain parenchyma and no dilated vessels (11).…”

Endovascular Treatment of Intracranial Ruptured Aneurysms Associated with Arteriovenous Malformations: A Clinical Analysis of 14 Hemorrhagic Cases

“…therefore, our therapeutic goal in this study was to reduce hemorrhage risk 12,18 . a large body of evidence has shown that the therapeutic strategy for aneurysms with coexisting aVMs depends on the aneurysm type and the particular clinical characteristics present 16,17,18 . When treating ruptured aneurysms with coexisting aVMs, the common idea is that associated aneurysms are high-risk factors, which should be given priority for treatment 1,9,18 .…”