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Symptoms and Signs of Brain Aneurysm

Doctor's Notes on Brain Aneurysm

A brain aneurysm is an abnormal bulge or ballooning of a blood vessel in the brain; the walls of an aneurysm are not as stable as normal blood vessel walls. Aneurysms often are found incidentally or when they either leak blood or burst (rupture). Signs and symptoms are variable and are related to the area where the aneurysm is located. However, a common sign of most aneurysms is a headache described as “the worst headache of my life.” Other signs and symptoms possibly encountered are visual defects, photophobia, face pain, nose bleeds, dilated pupils, focal neurological problems, confusion, nausea and vomiting, cardiac dysrhythmias, seizures, stroke symptoms, neck pain or stiffness, difficulty breathing and, in some patients, death. The signs and symptoms are mainly due to the blood that leaks or pours into the brain tissue, compromising brain cells and other brain components with inflammatory reactions and/or by putting pressure on them (for example, an expanding hematoma).

The cause of brain aneurysms is controversial; currently, genetic and environmental factors together is a favored theory but it may change. Medical conditions that increase risk for them include polycystic kidney disease, lupus, sickle cell anemia, endocarditis, fungal infections, hypertension, cancers, smoking, alcohol use, connective tissue disorders, head trauma and others.

Medical Author:
Medically Reviewed on 3/11/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.