This is a condition in which there is a weakness within an artery wall causing it to balloon out and sometimes rupture. In most cases involving the cerebral blood vessels these are present from birth and are asymptomatic and unrelated to migraine or other headaches.

Aneurysms are detected in some cases on MRI scans. MRA, which is performed similarly to MRI, can also be helpful in localizing them. Angiograms performed where contrast dye is injected through a catheter in the leg or neck arteries are needed to find the smallest ones, as well as before surgery to treat them is undertaken.

If an aneurysm further weakens and leaks blood into the brain tissue or if it ruptures, it then may create severe headaches and serious neurological conditions which may be life threatening.

The headache associated with an aneurysm is usually only present when the aneurysm is leaking or it ruptures. Thunderclap headaches or “crash” migraines may be associated with aneurysmal leaks. At times the headache associated with a ruptured aneurysm may occur during physical activity including during sexual intercourse. This is one of the reasons that headaches related to physical activity should be brought to the immediate attention of a physician.

Immediate neurosurgical attention is required for leaking and ruptured aneurysms. The use of the calcium channel blocker, nimodipine, may help to reduce the severity of the symptoms related to the rupture of the aneurysm. An asymptomatic aneurysm is often treated by surgery either by placing a clip on it or by inserting a coil into the aneurysm during an angiogram.