Keratoconus Whererei a te kiriwhatu

We do not know what causes it. We do know that it runs in whānau. People with keratoconus may also have:

• allergies
• eczema
• connective tissue disorders.

There are 2 theories about why it develops. People with keratoconus may have corneas that are:

• more easily damaged by things like eye rubbing
• less able to repair themselves when they are damaged.

Most people get keratoconus in their late teens to early 20s. It can begin at any age, but it rarely starts after the age of 30.

Early symptoms include:

• blurred or distorted vision
• increased sensitivity to light and glare (especially at night)
• eye redness and swelling
• mild eye irritation or strain. 

Later symptoms include: 

• more blurry and distorted vision
• increased short-sightedness (difficulty seeing objects far away) or astigmatism (another cause of blurry vision)
• a change in how your contact lenses fit.

Keratoconus generally gets worse over time, but this can happen quickly or slowly. It may only affect one eye but more commonly it happens in both eyes. If both eyes are affected you may have different symptoms in each eye.

Keratoconus can be diagnosed through an eye examination. Your optometrist or ophthalmologist will examine and measure your cornea to see if there is a change in shape. They may also take a detailed image of the surface of your cornea.

Your treatment will depend on your symptoms. It is best to avoid rubbing you eyes as this can damage your cornea and worsen symptoms.

If your symptoms are mild your vision can be corrected with glasses.

As your keratoconus gets worse and your cornea becomes more distorted, specially designed soft contact lenses can work well. As it becomes more advanced, hard contact lenses are usually the best choice to correct your vision. 

A procedure called corneal collagen cross-linking may also help to stop the keratoconus from getting worse. It uses eye drops and ultraviolet light to strengthen the collagen in your cornea, so it holds its shape better.

The procedure does not cure keratoconus, but it does stop it from getting worse. You will still need glasses or contact lenses after treatment.

Another treatment inserts very small plastic rings into the middle layer of your cornea to help to flatten it. You will still need glasses or contact lenses after the rings are inserted.

You may be advised to have a corneal transplant if:

• you are no longer able to wear contact lenses
• your cornea becomes scarred.

As with all transplant surgery, there is a risk that your body will reject the transplanted corneas, but generally this is a successful operation.