The decision to walk into a tattoo parlor and have someone needle-inject ink into the whites of your eyeballs is a bad one. That's according to ophthalmologists, a person who has had the procedure and even the guy who says he invented it.

Sclera tattooing, also known as tattooing the whites of the eyes, is so ill-advised that ophthalmologist Philip Rizzuto, a spokesman for the American Academy of Ophthalmology, is disappointed he even has to talk about it.

"I would strongly recommend against it," he said. The practice, he warned, can cause people to go blind and even lose their eye.

The world was reminded of the practice when Canadian woman Catt Gallinger of Ottawa, Ontario, Canada, recently posted the results of her sclera tattoo gone wrong.

On Sept. 5, the 24-year-old got her right eye inked, which caused purple ink to build up in her eye. It has since blurred her vision and is a source of pain. Next week, she anticipates undergoing surgery to remove the ink before it dries.

"I would not recommend anyone to do this," she said. "I don't think it's worth the risk."

Like a tattoo on your arm or hand, sclera tattoos involve placing ink within the skin, said Rizzuto, a clinical professor of surgery at Brown University. He explained the ink is injected into a very thin layer of skin called the conjunctiva, which covers the whites of our eyes. The result is the whites of our eyes change colors. It's as permanent as any tattoo.

Rizzuto said the danger lies in the inexperience of the hand holding the needle.

"Putting any kind of needle on the eye is very dangerous," he said. "We do that all the time, but we're trained for 12 to 18 years how to go about treating the eye."

An untrained person holding a needle near an eye offers a litany of dangers, Rizzuto said. The needle can scratch the eye, causing infection, or an unsteady hand could send the needle through the sclera, the hard whites of our eyes, and disrupt its normal workings. Blindness, the loss of an eye and vision loss are real potentials, he said.

"It's completely avoidable by not doing it."

Even the man who says he invented eye tattooing has reservations about how the procedure is performed.

Luna Cobra has been performing body modifications such as splitting tongues and scarifications since the mid-1990s. He started tattooing eyes about a decade ago, but admits the practice has made its way into the hands of people who don't know what they're doing.

He said sclera tattooing should be banned to anyone who is not a licensed eye surgeon. He claims the work is unregulated and as a result "people are hurt all the time." His proposed ban would include himself, but he said he's willing to give it up.

"I think the art is beautiful and it should continue," he said, "but I think it should continue in a safe manner."