Stem-Cell Transplant Restores Sight to Blind Man

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´╗┐Stem-Cell Transplant Restores Sight to Blind Man

A Blind Man 'Learns' to See

Stem-Cell Transplant Recipient Sees Motion But Has Trouble With Faces

Aug. 25, 2003 -- Michael May had been totally blind for four decades when he underwent the experimental operation that "restored" his sight three and a half years ago. While the surgery was a success, May, like others who have regained their vision after decades of blindness, still sees the world very differently from most people.

"I don't recognize faces at all, so I focus on hair length and color or body shape or height to figure out who someone is when I see them," he tells WebMD. "If I meet someone new I might memorize what they are wearing that day -- the color of their clothing or something else distinctive -- so that I can recognize them later."

May became blind at the age of 3 after losing one eye and was blinded in the other due to chemical and heat damage to his cornea. After one unsuccessful cornea transplant, May underwent a stem cell transplant in his right eye.

Imaging Issues in the Brain

May's current sight problems have little to do with his eyes, and everything to do with his brain. Although there are only a handful of cases like his, it is becoming clear that people who regain their sight after long-term blindness have more problems adapting to the visual world than those who lose and regain their sight later in life.

Now new research, which used magnetic resonance imaging (MRI) to track what is going on in May's brain, is helping to explain why. Researcher Ione Fine, PhD, and colleagues at the University of San Diego began their studies with May five months after his surgery, and the results of their research are published in the September issue of the journal Nature Neuroscience.

While May is able to detect both motion and color, he has a difficult time identifying objects and has the most problems recognizing faces and facial expressions. The MRI showed that the area of the brain that processes motion functions normally in May, but the area that processes form functions very poorly or not at all, Fine tells WebMD.

In tests conducted two years after his surgery, May had no difficulty recognizing simple shapes such as a square or circle. But he could identify only 25% of common objects that were presented to him, and he was able to tell whether an unfamiliar face was male or female only 70% of the time.

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