Donor Eyes Kept Responsive to Light for 10 Hours After Death

Researchers perfused donor human eyes with blood and oxygen, keeping the retinas responsive to light for up to 10 hours after death. The method also maintained retinal structure and surrounding cell health for up to 24 hours. Eimear Byrne and colleagues at the Barcelona Institute of Science and Technology inserted a flexible tube into the ophthalmic artery of donated eyes and used a custom device called the Eye-in-Care-Box to regulate pressure and flow of an oxygenated solution.

They tested the approach on both eyes from six donors, perfusing one eye while leaving the other untreated. Non-perfused eyes degraded rapidly after removal. In a separate test of 36 perfused donor eyeballs, 15 produced electrical responses to light comparable to those recorded in living people.

These responses lasted as long as 10 hours after death. Earlier work in 2022 achieved light responses for five hours. Thomas Johnson at Johns Hopkins University, who was not involved in the study, said the work represents an important step toward whole-eye transplantation.

He called maintaining light responses outside the body a tremendous feat. More than a million people in the UK are blind or partially sighted due to irreversible retinal conditions such as age-related macular degeneration. A partial face and whole-eye transplant performed in 2023 did not restore the recipient’s sight.

The retina’s connection to the central nervous system makes it especially vulnerable to oxygen loss. The researchers noted that regenerating optic-nerve fibers remains a separate challenge before vision can be restored through transplantation. Johnson said the perfusion method could support future strategies by reducing ischemic damage to donated eyes.