A brain vascular aneurysm, also known as a cerebral aneurysm, is a bulging or ballooning of a weakened portion of a blood vessel in the brain. This condition can be dangerous because the aneurysm may rupture, causing bleeding in or around the brain, known as a hemorrhagic stroke. Most cerebral aneurysms do not cause symptoms unless they grow large or rupture. When symptoms do occur, they may include sudden and severe headache, nausea, vomiting, vision problems, neck stiffness, or sensitivity to light. Treatment options depend on the size, location, and risk of rupture of the aneurysm and may include monitoring, endovascular procedures such as coiling or stenting, or surgical clipping. Early detection and intervention are crucial to prevent rupture and reduce the risk of serious complications.