Shania Twain had some nervous moments before saying yes to the regular Las Vegas casino gig she booked starting next year. Seems Shania suffers from a voice box disorder called dysphonia, which makes it tough to produce sounds—and which knocked her out of the spotlight for a few years.

Shania said she needed her doctor’s approval before booking a 120-show run at Caesars Palace. “It was totally dependent on the doctor because that was the key to me ever singing again,” Shania told the Las Vegas Sun.

“It’s a voice box issue in the muscle of the voice, very different from having a nodule on the vocal cords, which I’ve never had,” she said.

“It needs a long renewal time, and even today, I am still addressing it. You have to go through the entire recovery process. So once I visited the doctors after I left Vegas, I was more confident.”