Which artifact commonly results in echoes filling the lumen of small vessels?

Which artifact commonly results in echoes filling the lumen of small vessels?

• A. Partial volume
• B. Refraction
• C. Mirror image
• D. Range ambiguity

Answer: (A)

Partial volume artifact occurs when the acoustic sample volume (the voxel) contains more than one tissue type because of finite slice thickness and beam width. In small vessels, the lumen can be smaller than the slice thickness, so echoes from the vessel walls and surrounding tissue get averaged together within the same sample. This averaging makes the lumen appear filled with echoes, giving the impression that the lumen is echogenic rather than a distinct hollow space. This effect is especially noticeable in tiny vessels where the beam cannot neatly isolate the lumen from the walls. Other artifacts don’t produce this intraluminal filling. Refraction shifts structures laterally but doesn’t cause the lumen to fill with echoes. Mirror image creates a phantom duplicate across a strong reflector, not a fill of the vessel lumen. Range ambiguity involves mislocalization along the depth axis due to high PRF, not the appearance of a filled lumen.

Partial volume artifact occurs when the acoustic sample volume (the voxel) contains more than one tissue type because of finite slice thickness and beam width. In small vessels, the lumen can be smaller than the slice thickness, so echoes from the vessel walls and surrounding tissue get averaged together within the same sample. This averaging makes the lumen appear filled with echoes, giving the impression that the lumen is echogenic rather than a distinct hollow space. This effect is especially noticeable in tiny vessels where the beam cannot neatly isolate the lumen from the walls.

Other artifacts don’t produce this intraluminal filling. Refraction shifts structures laterally but doesn’t cause the lumen to fill with echoes. Mirror image creates a phantom duplicate across a strong reflector, not a fill of the vessel lumen. Range ambiguity involves mislocalization along the depth axis due to high PRF, not the appearance of a filled lumen.