How long can you live with untreated cerebral aneurysm?

Until it ruptures: Life expectancy depends on location, size, and characteristics that may make it more likely to rupture. This may be a very long time, or may cause problems sooner. These sometimes these can be treated with interventional radiology procedures. A neurosurgeon or neurologist would best be able to discuss the risk.

Depends: Which vessel? What size? When it is large enough to press on a critical structure that is a problem!wen it ruptures that is the problem! symptoms ceratinly push to surgical intervention.

Rare cause of death: Most people who have brain aneurysms die of some other cause, like heart disease or cancer. This is because most brain aneurysms don't bleed. Brain aneurysms are present in up to 15 million people in the us. The overall rate of rupture is very low. The rate of rupture depends on many factors, most importantly size, shape, personal history, family history and aneurysm location.