magnetic resonance angiography in the diagnosis of cerebral arteriovenous malformation and dural arteriovenous fistulas: comparison of time-resolved magnetic resonance angiography and three dimensional time-of-flight magnetic resonance angiography

Background: traditional digital subtraction angiography (dsa) is currently the gold standard diagnostic method for the diagnosis and evaluation of cerebral arteriovenous malformation (avm) and dural arteriovenous fistulas (davf). objectives: the aim of this study was to analyze different less invasive magnetic resonance angiography (mra) images, timeresolved mra (tr-mra) and three-dimensional time-of-flight mra (3d tof mra) to identify their diagnostic accuracy and to determine which approach is most similar to dsa. patients and methods: a total of 41 patients with avm and davf at their initial evaluation or follow-up after treatment were recruited in this study. we applied time-resolved angiography using keyhole (4d-trak) mra to perform tr-mra and 3d tof mra examinations simultaneously followed by dsa, which was considered as a standard reference. two experienced neuroradiologists reviewed the images to compare the diagnostic accuracy, arterial feeder and venous drainage between these twomraimages. interobserver agreement for different mra images was assessed by kappa coefficient and the differences of diagnostic accuracy between mra images were evaluated by the wilcoxon rank sum test. results: almost all vascular lesions (92.68%) were correctly diagnosed using 4d-trak mra. however, 3d tof mra only diagnosed 26 patients (63.41%) accurately. there were statistically significant differences regarding lesion diagnostic accuracy (p = 0.008) and venous drainage identification (p < 0.0001) between 4d-trakmraand 3d tof mra. the results indicate that 4d-trakmrais superior to 3d tof mra in the assessment of lesions. conclusion: compared with 3d tof mra, 4d-trak mra proved to be a more reliable screening modality and follow-up method for the diagnosis of cerebral avm and davf.