Keratoconus Surgery

Keratoconus is a disease in which the transparent layer at the front of the eye, the cornea, becomes thinner and progressively bulges forward. This condition, generally seen more often in women, changes the refractive power of the cornea and causes severe astigmatism and poor vision. In the final stage of this condition, also known as conical cornea, swelling and whitening occur. The cornea is the most important layer of the eye, where all the light entering the eye is refracted. Incorrect focusing in this layer therefore seriously reduces the quality of vision. The symptoms of keratoconus are frequent changes of glasses, visual disturbance, an allergic constitution, reduced vision that cannot be corrected with glasses, difficulty reading and inability to notice distant objects. Patients sometimes report that their vision is clearer when they press on their eyelids or pull the eyelids sideways. This can occur in keratoconus, but it should be known that the improvement is temporary. It is never possible to sharpen vision in this way. Keratoconus is seen in one in a thousand people, and when these symptoms appear a specialist should be consulted immediately. Otherwise the patient’s vision may deteriorate to the point of severe loss. This means a 95 percent loss of vision, and the patient may have difficulty seeing even one metre ahead. Although we do not call this total blindness, we can call it legal blindness. During treatment, people with this disease must never scratch or rub their eyes or apply firm pressure to them, so that the disease does not progress further.

Keratoconus generally appears in adolescence and is quite difficult to diagnose early in childhood; this requires comprehensive examinations. At first patients think they are myopic, but as they get older this gives way to keratoconus. The patient begins to change glasses constantly, but no improvement is seen despite the glasses. In patients considering excimer laser treatment, the disease is sometimes discovered by chance during a corneal examination. In keratoconus, where treatment must begin immediately, special hard contact lenses are used. These lenses do not stop the progression of the disease; they only prevent the centre of the cornea from bulging forward, correct the astigmatism and provide clearer vision, so that vision can be improved somewhat. As the disease progresses, however, this no longer works. Another treatment method is corneal transplant surgery, which is not always possible because corneas are expensive and donations are insufficient. Since the body may reject the tissue in 15 to 20 percent of cases, corneal transplant is a treatment preferred as a last resort. With advancing technology, it has become possible to halt this condition with corneal cross-linking, a treatment method that has become very popular in recent years.