Objectives: The aim of this study was to assess the sensitivity and specificity of pseudo-continuous arterial spin labeling (PCASL) magnetic resonance angiography (MRA) with 3-dimensional (3D) radial acquisition for the detection of intracranial arteriovenous (AV) shunts. Materials and Methods: A total of 32 patients who underwent PCASL-MRA, clinical magnetic resonance imaging (MRI)/MRA exam, and digital subtraction angiography (DSA) were included in this retrospective analysis. Twelve patients presented with AV shunts. Among these were 8 patients with AV malformations (AVM) and 4 patients with AV fistulas (AVF). The clinical MRI/MRA included 3D time-of-flight MRA in all cases and time-resolved, contrast-enhanced MRA in 9 cases (6 cases with AV shunting). Research MRI and clinical MRI were independently evaluated by 2 neuroradiologists blinded to patient history. A third radiologist evaluated DSA imaging. A diagnostic confidence score was used for the presence of abnormalities associated with AV shunting (1-5). The AVMs were characterized using the Spetzler-Martin scale, whereas AVFs were characterized using the Borden classification. Statistics were applied to assess intermodality agreement. Results: Compared with clinical MRA, noncontrast PCASL-MRA with 3D radial acquisition yielded excellent sensitivity and specificity for the detection of intracranial AV shunts (reader 1: 100%/100%, clinical MRA: 91.7%, 94.4%; reader 2: 91.7%/100%, clinical MRA: 91.7%/100%). Diagnostic confidence was 4.8/4.66 with PCASL-MRA and 4.25/4.66 with clinical MRA. For AVM characterization with PCASL-MRA, intermodality agreement with DSA showed values of 0.43 and 0.6 for readers 1 and 2, respectively. For AVF characterization, intermodality agreement showed values of 0.56 for both readers. Conclusion: Noncontrast PCASL-MRAwith 3D radial acquisition is a potential tool for the detection and characterization of intracranial AV shunts with a sensitivity and specificity equivalent or higher than routine clinical MRA.
Bibliographical noteFunding Information:
Received for publication May 23, 2017; and accepted for publication, after revision, July 26, 2017. From the *Department of Radiology, University of Wisconsin, Madison; †Clinic of Radiology and Nuclear Medicine, Basel University Hospital, Basel, Switzerland; Departments of ‡Neurological Surgery, §Biostatistics and Medical Informatics, and ||Medical Physics, University of Wisconsin, Madison. Conflicts of interest and sources of funding: none declared. Funded by NIH R01NS066982, Clinical and Translational Science Award (CTSA) program through the NIH National Center for Advancing Translational Sciences (NCATS), grant UL1TR000427. The content is solely the responsibility of the au-thors and does not necessarily represent the official views of the NIH. Tilman Schubert is supported by a fellowship grant (Helmut-Hartweg-Fonds) from the Swiss Academy of Medical Sciences. Correspondence to: Tilman Schubert, MD, Clinic for Radiology and Nuclear Medicine, Basel University Hospital, Petersgraben 4, 4031 Basel, Switzerland. E-mail: email@example.com. Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved. ISSN: 0020-9996/18/5302–0080 DOI: 10.1097/RLI.0000000000000411
- Arteriovenous shunting
- Magnetic resonance angiography