What is an Aneurysm? An aneurysm is a serious vascular condition in which a blood vessel wall becomes weak and bulges outward like a balloon. It can occur in different parts of the body, most commonly in the aorta (aortic aneurysm), brain (cerebral aneurysm), or peripheral arteries such as the popliteal artery. If left untreated, an aneurysm can enlarge and may rupture, leading to...