A cataract is a reduction in the transparency of an otherwise clear ocular lens. The lens focuses the light rays entering the eye so that they fall onto the retina. A cataract prevents the light rays from falling onto the retina, thus leading to a decrease in visual acuity.

How does a cataract arise?

Cataracts can be either acquired or congenital. Senile cataracts occur most frequently; an age-dependent cataract is found in 60 % of the population aged between 65 – 74. So far, the exact cause of cataract formation has not been completely determined. Among the prime risk factors for cataract development are age, gender (more frequent occurrence among women), overall illness, obesity, long-term use of certain medicines, smoking, etc. A cataract can arise at any age. We usually find them in young people and middle-aged people as a complication of other eye disorders and overall illness or following an accident. Generally, a congenital cataract can be found in children as the result of the mother’s having a viral illness (e.g. rubella) during pregnancy.

What subjective complaints can cataract cause?

A cataract causes a drop in the eye’s functioning, chiefly by reducing visual acuity. The degree of visual impairment varies (from a slight decrease to only preserving light perception) depending on the type and the development of the cataract. Common complaints among patients are hazy vision, visual impairment in bright sunlight and when driving, transient double vision and defects in colour vision. The speed with which the lens becomes clouded varies between individuals; usually, it is a matter of months to years.

When to visit your doctor?

You should consult an ophthalmologist following any impairment in vision. On the basis of a professional eye examination, the doctor will determine the cause of the impairment and prescribe a treatment.