Siemens Medical Solutions USA Inc. 1 article published in JoVE Medicine Time-Resolved, Dynamic Computed Tomography Angiography for Characterization of Aortic Endoleaks and Treatment Guidance via 2D-3D Fusion-Imaging Marton Berczeli1,2, Ponraj Chinnadurai1,3, Su Min Chang4, Alan B. Lumsden1 1Department of Cardiovascular Surgery, Houston Methodist Hospital, 2Department of Vascular and Endovascular Surgery, Semmelweis University, 3Advanced Therapies, Siemens Medical Solutions USA Inc., 4Department of Cardiology, Houston Methodist Hospital Dynamic computed tomography angiography (CTA) imaging provides additional diagnostic value in characterizing aortic endoleaks. This protocol describes a qualitative and quantitative approach using time-attenuation curve analysis to characterize endoleaks. The technique of integrating dynamic CTA imaging with fluoroscopy using 2D-3D image fusion is illustrated for better image guidance during treatment.