A new layer in the front layer of the human eye has been discovered by researchers at The University of Nottingham.
The findings, published in the journal Ophthalmology, could significantly help doctors carry out corneal grafts or transplants.
The layer has been called the “Dua’s Layer”, named after the researcher who led the study, Professor Harminder Dua.
Harminder Dua, Professor of Ophthalmology and Visual Sciences, said that the discovery means that ophthalmology textbooks will literally have to be re-written.
“Having identified this new and distinct layer deep in the tissue of the cornea, we can now exploit its presence to make operations much safer and simpler for patients.”
Clinicians across the world are starting to relate the tear or absence in this layer to diseases at the back of the cornea.
The cornea is located on the front of the eye and allows light to enter. Previously believed for made up of five different layers:
- Bowman’s layer
- The corneal epithelium
- The corneal stroma
- Descemet’s membrane
- The cornel endothelium
The Dua’s layer is located in the back of the cornea between the corneal stroma and Descemet’s membrane. It is extremely tough and strong despite being only 15 microns thick, it also impervious to air.
The newly discovered layer of the cornea is a significant advancement in our understanding of the human eye.
The new layer was discovered by simulating human corneal transplants on eyes collected from donors across the UK – given recent success in cultivated stem cells on human corneas, there might not be a need for donors in the future.
Small air bubbles were injected into the cornea of the eye to separate it into different layers. The researchers were able to study the layers a thousand times their actual size with electron microscopy.
Surgeons will benefit considerably by understanding more about the new Dua’s layer, which will improve outcomes for patients undergoing corneal grafts and transplants. There are over 65,000 penetrating corneal graft procedures being carried out worldwide each year, according to Eye Journal.
During corneal surgery, a method called the “big bubble technique” is used, whih involves injecting tiny air bubbles into the corneal stroma. Sometimes these bubbles burst, leaving the patient’s eye severely damaged.
However, now that doctors know they can inject the bubbles under the Dua’s layer instead of above it, the chances of tearing during surgery are significantly reduced.
The researchers say that corneal hydrops, a condition that occurs when water from inside the eye rushes in and leads to a fluid buildup in the cornea, is likely caused by a tear in the Dua layer.
“From a clinical perspective, there are many diseases that affect the back of the cornea, which clinicians across the world are already beginning to relate to the presence, absence, or tear in this layer.”
Written by Joseph Nordqvist