How your Cornea controls your eyesight

The human eye and how it processes images we see involves a series of complex biological processes taking place together, but sometimes the quality of vision can be impaired because of abnormalities in its structure.

Once of the most common irregularities found in the human eye that affects eyesight relates to the shape of the cornea.

The cornea is a transparent dome-shaped layer at the front of the eye that is incredible unique in its composition, in that it contains no blood vessels to deliver nutrients to it.

Instead, the cornea relies on tears and the aqueous humor fluid to provide it with the nutrients it requires to stay healthy and function effectively.

The role of the cornea in clear vision

Light enters the human eye from the outside world in straight lines, but in order for the brain to process light, it must first be bent or refracted by the eye.

The cornea is responsible for bending the vast majority of light that enters the eye and in a healthy and perfectly formed eye, the curve of the cornea will allow for accurate refraction to take place.

If the curve of the cornea is too steep or too flat, this affects the way in which light is refracted, causing it to land either before or behind the retina instead of directly on it.

When this takes place in the eye, it is referred to a refractive error and in order to correct the error, a lens must be placed in front of the cornea so that light can be repositioned and pinpointed onto the retina.

Establish permanent clear vision with Laser Eye Surgery

Refractive eye surgery is an alternative to glasses or contact lenses that permanently changes the optical power of the cornea so that it can refract light accurately as it passes through the eye.

During the procedure at Optilase Northern Ireland, an Excimer Laser is trained on the eye to remove a predetermined amount of corneal tissue in order to alter the natural gradient of the cornea.

Short sightedness: The focal point of the eye must be extended so that light no longer lands in front of the retina.

Long sightedness: In this instant the cornea is too flat and needs a greater curve so that light no longer lands behind the retina.

Laser Eye Surgery can also effectively treat astigmatism, which is another refractive error that manifests when the cornea is not spherical in shape.

For more information on Laser Eye Surgery at Optilase Northern Ireland, call 08000 121 565.