Narrator: This is Science Today. A brain aneurysm is a weak, bulging spot on the wall of a brain artery, which if large enough, can rupture and lead to internal hemorrhaging. Aneurysm sufferers typically have to choose between two treatments. One is called clipping and the other is called coiling. A University of California , San Francisco study has determined that they each work equally well. Dr. Claiborne Johnston, who led the study, explains.

Johnston : There are two ways of treating aneurysms – two main ways. One is with open surgery, where you open up the skull and you put a clip over the neck of the aneurysm and the other is by coiling where you go through a catheter through the groin and thread a catheter up to the brain and fill the aneurysm from the inside with coils.

Narrator: Before, it was uncertain whether the coiling treatment would be effective for over a year.

Johnston : What we found was that although there were some ruptures that occurred soon after both treatments, after one year, rupture was extremely rare in both groups.

Narrator: For Science Today, I'm Larissa Branin.