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Rapper and music producer Dr. Dre suffered a ruptured brain aneurysm that landed him in an ICU at Cedars Sinai Medical Center.

Most people who suffer a brain aneurysm have no symptoms until the aneurysm ruptures, causing bleeding in the brain.

Dr. Guillermo Linares, associate professor of neurology at St. Louis University, explained a brain aneurysm to FOx2Now.

"What a brain aneurysm is it's an abnormality in one of the [blood] vessels, the wall of the vessel in the brain. It is an area of weakness," he said. "This area of weakness allows for a small blister or pouch to develop and because, it's weaker, it has a tendency to rupture."

Dr. Linares, who didn't treat Dre, added: "When it ruptures, the high pressure with the blood inside the artery, pushes the blood out and it can cause brain damage. I think in lucky cases the bleeding stops right away and the only thing one would experience is a very severe headache."

Dr. Linares said anti-hypertensive medicine to control high blood pressure and avoid smoking can prevent brain aneurysms from rupturing.

"Those two things are the biggest modifiable risk that will probably prevent an aneurysm from rupturing."

Linares says there are warning signs to look for.

"So, the sudden onset of the worst headache of someone's life," he said. "Especially if accompanied by a difficulty with speaking or weakness in an arm or leg or an asymmetry in the face, should prompt a 911 call right away."