Which imaging study uses contrast to visualize the blood vessels?

• A. Angiography
• B. Barium enema
• C. Barium swallow
• D. Audiometry

Answer: (A)

Visualizing blood vessels requires a contrast agent that makes the vessels stand out on imaging. Angiography injects contrast into the blood vessels and uses X-ray imaging to trace the vascular lumen, producing a detailed map of arteries and veins. This allows detection of abnormalities such as aneurysms, stenosis, or occlusions. In contrast, barium enema and barium swallow introduce barium to the GI tract to image its structure, not the vasculature, and audiometry is a hearing test with no imaging involved. So the study that uses contrast specifically to visualize the blood vessels is angiography.