By Sydney Lupkin Dustin Vidrine stands outside his house in Lafayette, La. Annie Flanagan for NPR hide caption Dustin Vidrine's sight is disappearing — shrinking, really. He has retinitis pigmentosa, a rare, inherited eye disease that runs in his family. By the time he was in his 20s, he noticed that his vision had narrowed. It was especially apparent when he was looking at a computer or TV. "The bigger the screen, the harder it was to see because I'm only seeing one portion of detail at a time," says Dustin, 34, of Lafayette, La. "I would have to read like one letter at a time, whether I'm zooming in or not." Then Vidrine had kids. Fatherhood brought new challenges. Mixing baby formula was tricky because he couldn't see the tiny markings on the bottles to measure how much water to add. He wound up using a thick marker to make a bold line he could see. "It's just so much limitations," he says. He wishes he could throw a ball with his son, but he's now legally blind.…