Clarke was then transported to a neurological hospital for brain surgery.
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Though the procedure was considered "minimally invasive," Clarke says the pain afterward was "unbearable" and took about a week for her speech to come back properly after suffering from aphasia, a language impairment that sometimes follows strokes.
Eventually, she went back to working on "Thrones" with the knowledge that she had a smaller growth on the other side of her brain that doctors said could “pop” at any time. She pushed through filming, despite feeling weak and exhausted.
Then, after finishing Season 3 in 2013, she took a job on Broadway. While in New York, a brain scan revealed the remaining growth had "doubled in size" and needed surgery.
The procedure had failed, however, causing a massive bleed that forced doctors to operate again "the old-fashioned way," through her skull.
Clarke said the pain was even worse than the first surgery, leaving her in the hospital for a month to recover.
Now, Clarke says she is telling her truth after "keeping quiet all these years" and is looking forward to the future.
"In the years since my second surgery, I have healed beyond my most unreasonable hopes. I am now at 100 percent," she said. "There is something gratifying, and beyond lucky, about coming to the end of 'Thrones.' I’m so happy to be here to see the end of this story and the beginning of whatever comes next."