The angiographic appearance described as a 'string of beads' is characteristic of which condition?

• A. Atherosclerosis
• B. Embolism
• C. Fibromuscular dysplasia
• D. Saccular aneurysm

Answer: (C)

The beaded appearance on angiography reflects alternating narrowings and small dilatations along a mid-sized artery, caused by fibromuscular dysplasia. This condition is non-atherosclerotic and often involves the renal and carotid arteries, especially in women, producing segments where the vessel constricts (stenoses) interspersed with dilated areas (aneurysmal or hype hr) that create the string-of-beads pattern. Atherosclerosis tends to show diffuse or focal narrowing from plaque with possible calcification, not this periodic beading. An embolism causes sudden occlusion rather than a pattern of alternating constrictions and dilations. A saccular aneurysm shows a single outpouching or multiple focal aneurysms, not a repetitive narrow-dilation sequence. This classic beading is therefore characteristic of fibromuscular dysplasia.