A uniform dilatation of the arterial walls; most common type of aneurysm is called what?

• A. Fusiform
• B. Saccular
• C. Mycotic
• D. Pseudoaneurysm

Answer: (A)

A uniform dilatation of the arterial wall that extends along a segment is described as a fusiform aneurysm. This pattern means the entire circumference of the vessel expands evenly, producing a spindle-shaped enlargement when viewed in cross-section or along the vessel. It is the most common aneurysm type, often linked to processes that weaken the entire wall, such as atherosclerosis.

In contrast, a saccular aneurysm is a localized, pouch-like bulge on one side of the vessel with a neck; it’s not uniform along the artery. A mycotic aneurysm refers to an aneurysm caused by infection and can be either fusiform or saccular in shape, but the defining factor is the infectious etiology rather than the dilatation pattern alone. A pseudoaneurysm is a false aneurysm where there is a breach in the vessel wall with blood contained by surrounding tissues, not a true dilation of the arterial wall.

So, when the description emphasizes uniform, circumferential expansion of a vessel segment, fusiform aneurysm is the best fit.