Rare ‘tooth-in-eye’ surgery restores man’s vision after two decades

"It’s like watching people come out of a time capsule and reintroduce themselves to the world,” Dr. Greg Moloney said of the success of the procedure. “It’s highly emotional for us.” (Phil Chapman via CNN Newsource)

When Brent Chapman was 13, he took ibuprofen during a Christmas basketball game. It was a drug he had taken before, but what happened next was anything but routine: He had a severe reaction that caused burns all over his body, including on the surface of his eyes.

Chapman was in a coma for 27 days. He lost his left eye to an infection and lost most of his vision in the other. His body recovered, but his vision fully never returned.

“For the last 20 years, I’ve been having close to 50 surgeries trying to save this eye, most of them cornea transplants,” Chapman said of his right eye. “We would put a new cornea in. It would last sometimes just a few months or even up to years, but it would just kind of never heal.”

But Dr. Greg Moloney, clinical associate professor of corneal surgery at the University of British Columbia, was able to restore Chapman’s sight this year with a rare procedure that involved implanting Chapman’s own tooth into his eye.

“I’m very happy and am just taking in the world again, appreciating the little things. It’s been kind of surreal and kind of a euphoric feeling to it,” Chapman said.

The procedure, also known as tooth-in-eye or osteo-odonto-keratoprosthesis, involves removing a patient’s tooth, sewing a piece of it into the cheek and placing the structure into their eye.

It’s considered a last resort.

“It’s a situation where a standard corneal transplant simply won’t work,” said Dr. Vicente Diaz, assistant professor of ophthalmology and visual science at the Yale School of Medicine. Diaz was not involved with Chapman’s case but treats people who have Stevens-Johnson syndrome, the rare and sometimes fatal drug reaction that caused Chapman’s blindness.

The condition causes severe inflammation of the skin and mucous membranes, including the eyes. In some cases, Diaz said, the immune system attacks and destroys the limbal stem cells that are essential for keeping the cornea clear. Without these cells, corneal tissue becomes scarred and keratinized, as if the cornea has skin growing over it, blocking light from reaching the retina.

Stevens-Johnson syndrome can be triggered by any medication or infection, although certain drugs such as seizure medications, gout medications and antibacterial sulfa drugs carry a higher risk. There are also certain genetic factors that could put someone at a higher risk of developing the disorder. Diaz noted that it can occur at any point in a person’s life, even after previous exposure to the same trigger without incident.

A tooth for an eye

In a healthy eye, the cornea acts like a windshield, allowing light to pass through to the lens and then to the retina, where it is converted into electrical signals sent to the brain. The cornea’s clarity depends on adequate lubrication and a steady renewal of cells by limbal stem cells. In conditions like Stevens-Johnson syndrome, those systems fail.

When the cornea is permanently opaque and the eye rejects a cornea transplant, surgeons sometimes turn to tooth-in-eye surgery.

A canine tooth, which is the longest tooth in the human mouth, is extracted from the jaw, along with a thin layer of bone around the tooth that provides support and blood, keeping it alive. The tooth is then shaved into a 4 millimeter-thick block and drilled to hold a plastic optical cylinder, explained Dr. Ben Kang, Chapman’s oral maxillofacial surgeon and division head of Oral & Maxillofacial Surgery at Vancouver General Hospital.

The shaved tooth, with the lens in place, is implanted into the patient’s cheek or eyelid for several months, allowing soft tissue to grow around it.

“The tooth is a really ideal structure for holding a focusing element in place,” Moloney said. “It’s hard, it’s rigid, it survives in poor environments, and the body accepts it because it’s part of its own.”

The next step is to make a hole in the front of the patient’s eye to create space for the new complex.

Once the tooth-lens complex is integrated with living tissue, it is surgically attached to the front of the eye, replacing the damaged cornea’s function. Tissue from inside the patient’s mouth is used to cover the tooth part of the device, giving the new eye a pink shade. Light can then pass through the clear lens to the retina, enabling vision again, provided that everything behind the cornea — the retina and optic nerve— remains healthy.

Moloney said there are two types of candidates for the surgery: people like Chapman, who have tried every other procedure, or those who are so severely affected by their initial disease that doctors know from the outset that other options won’t work.

The surgery, which can take over 12 hours across two stages, is rare and performed by only a handful of specialists worldwide. But for people who qualify, success can mean regaining nearly normal vision.

“It’s like watching people come out of a time capsule and reintroduce themselves to the world,” Moloney said. “It’s highly emotional for us.”

Chapman’s tooth was extracted in February, and the structure was placed into his eye in June. His last surgery, which straightened the lens to correct visual distortion, took place August 5.

Regaining the human connection

Chapman was fitted with glasses on August 13 and now has 20/30 vision, meaning he can see details at a distance of 20 feet that a person with perfect vision can see at 30 feet.

The first thing he saw after his surgery was the skyline from Moloney’s 16th-floor office.

“It’s really indescribable, to be able to see the whole city and how there’s a whole world that’s just intersecting. When you’re blind or low-vision, you’re not seeing that, and you’re kind of in your head more. There’s a lot more mental chatter, and it can be difficult,” Chapman said. “Dr. Moloney and I made eye contact for the first time, and we both got quite emotional. I haven’t really made eye contact in 20 years.”

Before the tooth-in-eye surgery, Chapman was close to giving up hope.

“We definitely didn’t have any more options. The transplants were lasting such a short time, and they were becoming more risky to do surgically,” he said. “Emotionally, even when I would get a new one, I knew it wasn’t going to last. This opened a new door for me and a new chapter in my life. This also provides more stability.”

Chapman is looking forward to traveling – with Japan being on the top of the list – but he wants to “just see the world and take it all in.”

Chapman’s favorite sight? His niece and nephew.

“I have a niece and a nephew that are 4 and 2. They’re just so cute and so much fun,” he said.

He is also a massage therapist and is looking forward to working again. “I’ve had a lot of time off work in the last couple of years with surgeries. I can give back and help people in pain and not make everything about me, and I think psychologically, that’s very helpful.”

Above all, Chapman said, he is excited to dream again and “to not be limited by the instability of this condition and be able to plan and think ahead.”

“Before, I would always be afraid to plan because I’m afraid I’ll need emergency surgery or have an infection. It was so unpredictable, I would make these plans, and it would be heartbreaking when I couldn’t do them,” he said.

Having “human connection again visually” is something that people take for granted but is very powerful for people with poor vision.

“We’ve been with him since he was a teenage boy. He’s waited till he’s 34 to get that,” Moloney said. “We’ve all waited a long time.”

By Asuka Koda, CNN