Damage to the surface of the cornea causes pain and loss of vision, but regenerative therapies are providing a clearer, brighter future.
If the eyes are the window to the soul, then it is the cornea that lets the light enter.
For more than 200 years, physicians have been preoccupied with keeping this dome-shaped, transparent surface in front of the iris and pupil clear. German surgeon Franz Reisinger was the first to attempt a corneal transplant in animals in 1818. And in 1838, US ophthalmologist Richard Kissam tried to replace the opaque cornea of a young patient with the healthy cornea of a pig, but the procedure failed when the transplant was rejected. The first successful transplant in humans was in 1905, but outcomes remained poor until the mid-twentieth century, when developments in infection control, anaesthesiology, surgical techniques and immunology vastly improved the success rate of corneal transplantation. In the twenty-first century, advances in cell-culture techniques and bioengineering have opened the door to regenerative treatments for people with damage to one or both corneas.
Unclouded vision requires a clear cornea. Its epithelial surface constantly renews itself to maintain an unblemished, uniformly refractive surface. Cells that are shed from the surface are replaced by new ones that emanate from a small population of stem cells located at the edge, or limbus, of the cornea.
If the stem cells at the limbus are damaged, the renewal process is interrupted. The complete or partial loss of these stem cells — limbal stem-cell deficiency (LSCD) — allows the opaque conjunctiva to grow over the cornea. This can lead to intense pain and, in the most-severe cases, blindness.
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| Let there be sight -David Holmes |
Read more: Corneal Repair: A Clear Vision!
Nature Video: Repairing the cornea: let there be sight
Source: Nature
