Carlene Knight's vision was so bad that she couldn't even maneuver around the call center where she works using her cane.
"I was bumping into the cubicles and really scaring people that were sitting at them," says Knight, who was born with a rare genetic eye disease.
But that's changed as a result of volunteering for a landmark medical experiment. Her vision has improved enough for her to make out doorways, navigate hallways, spot objects and even see colors.
"It's nice. I don't scare people and I don't have as many bruises on my body," Knight says, laughing.