Science

Human eyeball successfully transplanted for the first time

Aaron James with Eduardo Rodriguez

Russ Geltman/NYU Langone Health

In a world first, surgeons have performed an eyeball transplant. It is uncertain if the recipient will be able to see using his new eye, but the procedure remains a significant step towards one day restoring vision in people who have experienced severe eye injuries.

On 27 May, Eduardo Rodriguez at NYU Langone Health in New York and a team of more than 140 others performed the eye transplant alongside a partial face transplant in Aaron James, a 46-year-old power line worker from Arkansas. To date, fewer than 50 facial transplants have been performed and none included an eye. Whole-eye transplants were previously deemed nearly impossible due to the organ’s complexity.

“I would like to thank the donor and the donor family. Without them, none of this could have been possible. I have the utmost respect for them to make this decision, to help people they don’t know, to give me this gift,” said James during a press conference on 9 November. “Before the transplant, emotionally, I was a little down. My confidence level was a little low. But since the transplant, I tell people I can’t walk past the mirror without looking at it. It has made me stand up taller. It’s great.”

James was severely injured in June 2021 after his face touched a live wire, sending a 7200-volt shock through his body. He lost most of the left side of his face, including his left eye, as well as much of his left arm.

Rodriguez and his team transferred the nose, lips and bone segments underlying the left cheek and chin of a deceased donor to James, along with most of the tissue beneath the right eye. They also transferred the donor’s entire left eye including the eyelids, eyebrows and eye socket. The procedure lasted about 21 hours.

The first challenge was extracting the intricate network of blood vessels surrounding the eyeball. Unlike other facial features, the eye receives blood from the brain region directly behind the eyeball. So, the surgeons had to partially remove the donor’s skull to access these vessels.

To avoid having to remove part of James’s skull too – which would have meant operating near his brain – the surgeons connected the vessels to others in the donor’s face. This allowed the team to re-establish blood flow to the eye within 25 minutes of the surgical procedure and bypass the brain. Then later, during the transplant itself, they connected these vessels to some in James’s neck.

Transplant procedure

The transplant procedure

Joe Carotta/NYU Langone Health

Removing the donor’s skull also gave surgeons better access to the optic nerve. This bundle of nerve fibres transmits information from the eye to the brain, enabling us to see. Doctors have never successfully reconnected a severed optic nerve. In an attempt to do so, Rodriguez and his team preserved as much of the donor optic nerve’s length as possible. This, they reasoned, would maximise the chances of the nerve fibres regenerating and establishing a connection with James’s brain.

They also took stem cells – which can develop into different types of specialist cells – from the donor’s bone marrow, and injected them into the site where the donor optic nerve and James’s optic nerve met, to further stimulate nerve growth.

More than five months after the surgical procedure, the eyeball appears to be healthy. It has sufficient blood flow and internal fluid pressure and can produce tears. Some of the nerve cells critical for sight are also alive, though James is unable to see using the eye and might never be able to do so, says Rodriguez.

“That’s an achievement, just keeping the globe viable, alive and healthy,” says Damon Cooney at Johns Hopkins University in Maryland, who wasn’t involved in the surgery. “[But] we need to be careful about raising people’s expectation or hopes in excess of what’s technically feasible at this point.”

“I think from our standpoint, the fact the individual survived the operation, the fact we’ve not had any complications whatsoever – and there could have been many – is a success,” says Rodriguez.

James can also eat and breathe on his own thanks to the surgery. “We forget about those [aspects] because everyone’s so focused on the eye. But the fact that we can given this person another chance at a normal life with the possibility of some form of sight is wonderful,” says Rodriguez.

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