Donor retinas respond to light 10 hours after death
Get the Health newsletter
Daily health & science — research, biotech, public health, the studies worth knowing. Free.
- Eimear Byrne's team at the Barcelona Institute of Science and Technology kept human eyes responding to light for up to 10 hours after death using a custom perfusion device called the Eye-in-Care-Box — double the 5-hour record set in 2022.
- The Eye-in-Care-Box inserted a flexible tube into the ophthalmic artery and used sensors to automatically regulate pressure and flow of an oxygenated solution, mimicking conditions inside the body.
- Of 36 donor eyeballs perfused, 15 retinas produced electrical responses to light similar to those measured in living people, though researchers noted it is unclear why the remaining 21 did not respond.
- The perfusion system preserved retina structure and surrounding cell health for up to 24 hours, while non-perfused eyes from the same six donors degraded quickly after removal.
- Thomas Johnson at Johns Hopkins University, who was not involved in the study, called maintaining light responses outside the body 'a tremendous feat' and an important step toward whole-eye transplantation.
- A major remaining obstacle is regenerating fibers in the severed optic nerve so a transplanted eye can connect to visual centers in the brain — without that, 'a donor eye will have no way of communicating visual sensation to the recipient's brain,' Johnson said.
- The researchers said the Eye-in-Care-Box could also serve as a platform for testing vision-related drugs and therapies in human eyes rather than in animal models.
Why it matters: More than a million people in the UK alone are blind from irreversible retinal conditions like age-related macular degeneration, and a 2023 whole-eye transplant failed to restore sight largely because retinal tissue degrades so quickly without oxygen. By keeping donor retinas metabolically healthy for 24 hours and light-responsive for 10, Byrne's work directly tackles the ischemic-damage barrier that has blocked whole-eye transplantation.
