To optimize detection of low-velocity endoleaks on color Doppler, which velocity setting is commonly used?

• A. 5 to 7 cm/sec
• B. 15 to 20 cm/sec
• C. 30 to 40 cm/sec
• D. 50 to 60 cm/sec

Answer: (A)

Lower the color Doppler velocity scale to a very low value, around 5–7 cm/s. This increases sensitivity to slow-flow signals, which is typical for endoleaks that involve sluggish, retrograde flow into the aneurysm sac. If you use a higher scale, those slow jets may not be colored at all, making the leak easy to miss. The trade-off is that very low scales can introduce aliasing for any faster flow in the study, so you may need to adjust the region of interest and use targeted interrogation to confirm findings.