Arterial spin labeling MR imaging aids to identify cortical venous drainage of dural arteriovenous fistulas

Abstract

Cortical venous drainage (CVD) increases the probability of intracranial hemorrhage and mortality rate of dural arteriovenous fistulas (DAVF). Although digital subtraction angiography (DSA) is the most accurate method to determine CVD in DAVFs, this modality has limitations due to its invasive nature and radiation issues. The purpose of this study was to evaluate the diagnostic utility of arterial spin-labeling perfusion-weighted images (ASL-PWI) to identify CVD in patients with DAVF.The Institutional Review Board of our hospital approved this retrospective study. ASL-PWI features of 22 patients with DAVF were retrospectively reviewed for the presence of bright signal intensity in cortical veins and brain parenchyma. DAVF with bright signal intensity in cortical veins and/or brain parenchyma was regarded as having CVD. Using DSA as a reference standard, sensitivity, specificity, positive predictive value, and negative predictive value of ASL-PWI for detecting CVD were calculated.Based on DSA features, 11 (11/22, 50%) patients were classified as having “aggressive” pattern with CVD. Eleven (11/22, 50%) patients also showed bright signal intensity in cortical veins (9/22, 41%) and/or brain parenchyma (4/22, 18%) on ASL-PWI. The 11 patients who had “Aggressive” pattern on DSA were the same 11 patients who were classified as having “aggressive” pattern on ASL-PWI. ASL-PWI showed perfect diagnostic performance for identifying CVD with sensitivity, specificity, positive predictive value, and negative predictive value of 100% for all.Thus, ASL-PWI could be used as a noninvasive mean to predict the presence of CVD in patients with DAVFs. It has the potential as a screening tool to evaluate DAVF prior to invasive DSA.

Clinical applications of arterial spin labeling of the intracranial compartment in vascular anomalies—A case-based review

“…In such cases, ASL suggests the presence of shunting that can be confirmed by conventional angiography (Figure 5). ASL has been shown to improve the detection of small vascular anomalies and small aneurysms 13 (Figures 5,6,7). This finding on ASL imaging can be confirmed by conventional angiography.…”

“…In patients with dAVF, cortical venous drainage increases the risk of intracranial hemorrhage and death. 7 Digital subtraction angiography (DSA) is the most accurate method to diagnose dAVF and determine the presence of cortical venous drainage. 7 However, it is essential to note that DSA is an invasive technique that involves radiation and associated risk.…”

“…7 Digital subtraction angiography (DSA) is the most accurate method to diagnose dAVF and determine the presence of cortical venous drainage. 7 However, it is essential to note that DSA is an invasive technique that involves radiation and associated risk. ASL is a sensitive tool in detecting dAVF and may be the only abnormal sequence in some cases (Figure 5, 6).…”

“…6 Isolated cases regarding ASL findings in AVM and AVF have also been reported. 7 While such cases display perfusion-related changes on ASL, a collective discussion and characterization of the specific ASL imaging features of vascular anomalies have not been depicted.…”

“…In patients with dAVF, cortical venous drainage increases the risk of intracranial hemorrhage and death. 7…”