Which imaging modality is typically required to classify endoleak type after EVAR?

• A. Cross-sectional imaging such as CT angiography.
• B. Duplex ultrasound alone.
• C. Plain radiographs.
• D. PET-CT.

Answer: (A)

Determining endoleak type after EVAR hinges on imaging that shows both the graft and the blood flow into the aneurysm sac; CT angiography is typically required because it provides high-resolution, three-dimensional visualization of where the leak originates and how the sac is filling. This detail lets you distinguish the main leak sources: attachment-site leaks or graft junction leaks (type I or III, which carry high pressure and usually need prompt intervention), retrograde flow from branch vessels into the sac (type II), or other fabric-related issues. CT angiography also assesses sac expansion, which informs urgency and treatment planning.

Duplex ultrasound can detect the presence of flow, but its ability to precisely identify the leak’s source is limited and operator-dependent. Plain radiographs show stent-graft position but not intra-sac flow or leak origin. PET-CT isn’t used for classifying endoleaks, as it doesn’t reliably define the hemodynamics of the leak.