Which color Doppler velocity setting is commonly used to detect low-velocity Type II endoleaks?

• A. 2 cm/sec
• B. 7 cm/sec
• C. 15 cm/sec
• D. 25 cm/sec

Answer: (B)

Detecting low-velocity Type II endoleaks relies on making slow flow visible on color Doppler. The velocity scale (color Doppler sensitivity) defines the maximum velocity that will be encoded as color. If the scale is too high, slow leaks may not colorize and can be missed. Type II endoleaks usually come from lumbar or mesenteric branches and flow into the aneurysm sac at a low velocity, so you want a low sensitivity setting to reveal those subtle jets. A value around 7 cm/s strikes a good balance: it’s low enough to show slow leaks but not so low that noise and tissue movement overwhelm the signal. Choosing a setting as low as 2 cm/s can increase susceptibility to noise, while higher settings like 15 or 25 cm/s may suppress the slow flow entirely, making the endoleak harder to detect.