Eye diseases
Keratoconus: symptoms, diagnosis and specialty contact lenses
Keratoconus is a condition where the cornea — the clear front surface of the eye — becomes thin and starts to bulge outwards into a cone shape. It usually starts in the teenage years and can affect both eyes.
What is keratoconus?
A healthy cornea has a smooth, dome-like curve that focuses light evenly. In keratoconus the cornea thins and bulges into a cone, so light focuses unevenly and vision becomes blurry or distorted.
Common symptoms of keratoconus
- Blurry or distorted vision
- Increased sensitivity to light and glare
- Difficulty seeing clearly at night
- Frequent changes in glasses or contact lens prescription
- Double vision in one eye
How is keratoconus managed?
In some cases keratoconus can be managed with special contact lenses; in others, surgery may be needed. An eye care professional can assess your corneas and explain which option suits your eyes.
Specialty contact lenses
Lenses such as scleral lenses vault over the cornea and rest on the white of the eye (the sclera), with a liquid reservoir in between. This gives the eye a smooth optical surface and can help people with keratoconus see more clearly.
Surgery
Where lenses aren't enough, an eye surgeon may recommend a surgical option. We refer you when this is needed.
When to see an eye care professional
If your glasses or contact lens prescription keeps changing, or your vision is becoming distorted, have your corneas checked. Early diagnosis helps you plan the right management.
Frequently asked questions
When to go to a hospital instead
Go to the nearest hospital emergency department immediately if you have:
- Sudden loss of vision
- Flashes of light or a shower of new floaters
- Eye injury or chemical splash
- Severe eye pain or a very red, painful eye
- Double vision that comes on suddenly