In Doppler imaging of an intimal flap, what does a longitudinal view typically reveal?

• A. Blood flow on both sides of the flap
• B. Flow proximal to the flap only
• C. No flow near the flap due to occlusion
• D. Flow distal to the flap only

Answer: (A)

In a Doppler long-axis view of an intimal flap from dissection, you see two separate flow channels separated by the flap: flow in the true lumen on one side and flow in the false lumen on the other. The flap serves as a mobile partition, so the Doppler signal appears on both sides as two distinct streams, often with different velocities. This is why the correct description is blood flow on both sides of the flap. If the flap were occlusive, you’d lose flow near it, and you wouldn’t typically see flow in just one region (proximal or distal) alone.