If you're a fan of Game of Thrones, then you are likely familiar with one of its most popular stars, Emilia Clark. Clark plays Daenerys, Mother of Dragons and all-around badass warrior woman. But Clark is incredibly strong for reasons that have nothing to do with her character on the popular show.

In a recent interview, the actress revealed that she's undergone two brain surgeries in the last eight years to repair two different life-threatening brain aneurysms. In 2011, while working out with her trainer, Clark recalls suffering a violent, debilitating pain in her head. She was diagnosed with a subarachnoid hemorrhage (SAH), a life-threatening type of stroke. Luckily for Clark, doctors acted quickly to repair the hemorrhage; approximately one-third of SAH patients die immediately or very soon after an aneurysm.

Two years later, her doctors discovered another aneurysm, and Clark spent a month in the hospital recovering from her second surgery. Incredibly, Clark has healed remarkably well since her scary ordeals. But her story has opened up a lot of people's eyes to the dangers of aneurysms.

Ruptured brain aneurysms can come on very, very suddenly, and require immediate medical attention. They cause bleeding around the brain, called a subarachnoid hemorrhage (SAH). There are some warning signs and troubling symptoms to be aware of: sudden and severe headache (people describe it as the worst headache of their life), nausea or vomiting, a stiff neck, blurred or double vision, a sensitivity to light, or seizures. Other symptoms of SAH include a drooping eyelid, a dilated pupil, pain above or behind your eye, confusion, weakness or numbness in the limbs, and loss of consciousness.

Every single second counts in the event of a SAH. Experts warn that if you experience any of the symptoms above, 911 should be called immediately. Waiting for a friend or family member to take you to the hospital is not advised, as paramedics may need to perform potentially life-saving procedures in the ambulance. You may not experience all the symptoms listed, but a sudden severe headache, nausea or vomiting, and a stiff neck are the most common.

Aneurysms that have not ruptured will typically not present symptoms. They're usually small and are found incidentally during tests or scans for other conditions. If the aneurysm becomes larger, it can press on the nerves in the brain and cause symptoms. These symptoms include a drooping eyelid, blurred or double vision, a dilated pupil, pain above or behind the eye, and weakness or numbness in the limbs. If you experience any of these symptoms, seek medical attention for further tests.

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