The key to the procedure is a specially tuned laser that destroys the natural brown pigment melanin in the iris, the eye’s central colored portion. The laser treatment takes about 20 seconds, with the color change occurring gradually over the next two to three weeks.

The idea of using laser light to change eye color makes sense, Dr. Elmer Tu, associate professor of clinical ophthalmology at the University of Illinois at Chicago and a spokesman for the American College of Ophthalmology, told CBS News. “Theoretically, it’s possible if you go in and laser the eye to release the pigment that causes brown eyes,” he said.

But Dr. Tu said safety could be an issue. The released pigment “has to go somewhere,” he said, adding that a potentially blinding condition called pigmentary glaucoma is known to be associated with the chronic seepage of melanin into the fluid within the eye.