Information on Eye Conditions
What is the Cornea?
Fuchs Endothelial Dystrophy
What is Keratoconus
What is the Cornea?
The cornea is the clear, transparent and dome shaped tissue covering the front of the eye. If the cornea becomes distorted in shape, scarred, or hazy (opaque) from disease or injury, the light rays passing through it are distorted and the vision is reduced.
What is Fuchs' Endothelial Dystrophy?
The inside surface of the cornea is lined by a layer of cells called endothelial cells. This special layer of cells works as a pump that keeps the cornea from becoming thick and waterlogged. This layer of cells can be lost as a result of disease, injury or previous eye surgery (e.g. cataract surgery or glaucoma surgery).
It can also occur spontaneously in patients with a condition called Fuchs’ Endothelial Dystrophy. In this condition, the endothelial cells to not survive long enough to last a lifetime and they can lose enough endothelial cells to start experiencing some blurring of vision from the ages of 40 to 60. In severe cases, the cornea can become very swollen and waterlogged (oedema) to the point where blisters can form. This can make the eye intermittently painful when they burst.
What is Keratoconus?
Keratoconus is a condition characterised by the progressive thinning and protrusion of the cornea (the transparent clear structure at the front of your eye) so the cornea becomes irregular in shape, thus reducing vision. In some cases, keratoconus can progress to the point where patients need a special contact lens or a corneal graft procedure to have good sight.
Image from Dorlands, 2000
WHAT IS A PTERYGIUM?
A pterygium is a non-cancerous growth on the surface of the white part of the eye that grows over the front of the cornea (the clear window at the front of the eye).
A pterygium usually grows very slowly, over many years. It is more common in people who have been exposed to a lot of sunlight during their lifetime.
A pterygium may cause one or more of the following:
- Dissatisfaction with the cosmetic appearance of the eye
- Redness of the eye
- Eye discomfort - this is usually a dry or gritty sensation
- This is caused by drying of eye at the surface of the pterygium or next to it
- In severe cases, a pterygium
- can grow over the central part of the cornea and can cause blurred vision, or
- may restrict the movement of the eye, causing double vision.