“Like two years ago, I had a weird, extremely rare form of vasculitis that destroyed my vision, destroyed my hearing, and destroyed all my balance,” Kutcher said. “It took me about a year to put everything back together. You don’t really appreciate it until it’s gone, until you’re gone, “I don’t know if I’ll ever be able to see it again. I don’t know if I’ll ever be able to hear again. I don’t know if I’ll ever be able to walk again.” Kutcher added that he is “lucky to be alive.” Vasculitis is an autoimmune disease that results in inflammation of the blood vessels. Various diseases such as Cogan’s syndrome fall under the category of vasculitis. Kutcher did not disclose the details of his diagnosis. “The moment you start seeing your obstacles as things that are made to give you what you need, that’s when life starts to be fun,” Kutcher added of his personal growth since his diagnosis. “You start surfing over your problems instead of living under them.” Kutcher recently appeared in a supporting role in BJ Novak’s directorial effort “Vengeance.” He will soon reprise his starring role as Michael Kelso in “That ’90s Show,” Netflix’s upcoming “That ’70s Show” sequel. “It was really nostalgic to be back on set,” Kutcher told Variety at the red carpet premiere of “Vengeance” last month. “It’s all the same people who did ‘That ’70 Show,’ so it was pretty weird.” Kutcher went on to explain that he and his wife, “That ’70s Show” actress Mila Kunis, felt returning to the property was the right thing to do. As the actor said, “Mila and I were thinking about it. We thought, “Listen, we’re only in the position we’re in because of this show, so let’s go back and do this. We just got back and had fun for a week. It was so random and fun.” Watch a preview of Kutcher’s appearance on “Running Wild With Bear Grylls: The Challenge” in the video below.