The term that describes a balloon-type, bulging of a blood vessel is an aneurysm. An aneurysm occurs when the wall of a blood vessel weakens and causes a localized dilation or bulge. It can develop in various parts of the body, but the most common types are cerebral aneurysms (in the brain) and aortic aneurysms (in the aorta, the body's main artery). If left untreated, an aneurysm can rupture and result in severe bleeding, which can be life-threatening. Therefore, it is important to identify and address aneurysms promptly.
