What are aneurysms and pseudoaneurysms, and how do they differ?
An aneurysm (also known as a true aneurysm) is dilation of a vessel in which all three layers of the vessel wall remain intact. A pseudoaneurysm (also known as a false aneurysm) is a contained rupture and implies disruption of at least part of the aortic wall (i.e., the intima, media, or both), with intact adventitia. Pseudoaneurysms are potentially highly unstable lesions. They are often post-traumatic or iatrogenic in nature