Keratoconus


Keratoconus, sometimes called conical cornea, is a condition causing poor vision and it affects many young Australians.  This condition varies from extremely mild (with little or no effect on vision) to quite severe with a marked reduction in vision.

In keratoconus, the cornea becomes increasingly thin and uneven over time. So, instead of maintaining an even curve (like the side of an orange), over a period of time it starts to bulge and become uneven (more like the side of a pear).  As the condition progresses, vision deteriorates, sometimes rapidly. However, it does not cause blindness.  Keratoconus usually starts to develop in the teenage years but it is sometimes only picked up when a person has a consultation for laser eye surgery later in life.  The progression of keratoconus usually lasts 10-20 years before stabilising.
How is your Keratoconus treated?

The treatment for keratoconus depends on the severity of the disease.

  • If you have mild keratoconus you may have minor symptoms and there may be no consequence other than being unsuitable for laser eye surgery. Milder forms of keratoconus can commonly be corrected with prescription glasses.

  • As the keratoconus progresses, glasses are unable to correct the increasing distortion in your cornea.  Hard contact lenses are commonly used, although some patients find these lenses difficult to tolerate.

  • Mild to moderate keratoconus can be treated by re-shaping the abnormal corneal shape with small, thin crescents of plastic, called corneal rings. Using a special laser, a circular channel is created within the cornea without touching the outside surface. Then, through a tiny incision, the corneal rings are inserted into the cornea. The corneal rings flatten the cornea and return it to a more natural shape. They are designed to stay permanently within the eye.

  • The progressive changes in the shape of the cornea which occur in keratoconus can be slowed or stopped by performing collagen cross-linking. This technique uses a combination of specialised eye drops and ultraviolet light to increase the stiffness of the cornea. This treatment has the dual effect of stopping further shape changes and, to a lesser extent, improving vision by stabilising the shape of the cornea. Collagen cross-linking is only available on individual application through the TGA Special Access Scheme.

  • In severe cases of keratoconus, where the cornea is very thin and distorted, a corneal transplant is usually performed. This can either be a full thickness corneal transplant, or in younger patients a corneal transplant where the patient’s own corneal inner lining is retained to help prevent rejection of the transplanted cornea. Although corneal transplantation is a very successful procedure, the recovery time may be prolonged (several months to years) and because of rejection issues, a transplant will typically last for only 10-15 years.