Abstract 122: Transit Time on Digital Subtraction Angiography Correlates with Cerebral Arteriovenous Malformation Flow Measured by Quantitative Magnetic Resonance Angiography

Abstract

Introduction: Digital subtraction angiography (DSA) currently provides angioarchitectural features of cerebral arteriovenous malformations (AVMs) but its role in the hemodynamic evaluation of AVMs is poorly understood. Here, we assess transit time (TT) of contrast on DSA relative to AVM flow measured using quantitative magnetic resonance angiography (QMRA). Methods: Patients seen at our institution between 2007 and 2014 with a cerebral AVM and DSA and QMRA obtained prior to any treatment were retrospectively reviewed. TT on DSA was defined as time needed for contrast to change image intensity from 10%-100%, 100%-10%, and 25%-25%. TT was correlated to AVM total flow and angio-architectural features. Results: 33 patients (mean age 34.8 years) were included. 7 patients presented with hemorrhage. Mean AVM volume was 13.61 mL (range 0.28-84.2 mL). Higher total flow significantly correlated with shorter TT100%-10% and TT25%-25% (P=0.04, P=0.03, respectively). Total flow was also significantly related to the ratio sum of draining vein diameters/TT (TT10%-100% P=0.04, TT100%-10% P=0.01, TT25%-25% P=0.02). Presence of venous stenosis (P=0.01) and arterial ectasia (P=0.03) correlated significantly with TT100%-10%. TT was not significantly related to hemorrhagic presentation, deep drainage, single draining vein, or Spetzler-Martin grade. Conclusions: TT and the ratio sum of draining vein diameters/TT correlated significantly with AVM total flow measured using QMRA, and so TT along with venous diameters determined from DSA may be used as a surrogate for AVM flow.