What characteristic imaging finding is associated with fibromuscular dysplasia?

In the context of fibromuscular dysplasia, the characteristic imaging finding known as the "string of beads" is a result of alternating segments of stenosis (narrowing) and aneurysm (dilation) due to the abnormal proliferation of the smooth muscle and fibrous tissue in the arterial wall. This pattern creates a distinctive appearance on imaging, particularly angiography, where the affected artery (often the renal arteries) shows a series of alternating narrow and dilated segments that resemble a string of beads.

This finding is crucial in diagnosing fibromuscular dysplasia, as it is a hallmark feature of this condition. Understanding this imaging result helps distinguish it from other vascular conditions where different patterns of narrowing or obstruction might be present. Recognizing the "string of beads" pattern can guide appropriate management and treatment, emphasizing the importance of imaging characteristics in vascular diseases.