Due to the high number of cases, Lazy eye or Amblyopia has great social importance. Its frequency, between 1% and 4% of the population, could be greatly reduced through the early detection of this defect in children , but undetected it becomes irreparable

What is a lazy eye?

A lazy eye or amblyopia occurs when the development of vision in one of the eyes is worse than in the other during a critical period in the evolution of the visual system such as infancy. We have two eyes which send images to our brain, which is in charge of merging them into one single image. When the brain of a child receives two different images, because of strabismus and therefore each eye is looking at a different place, one of these images is canceled out to avoid double vision. In the same way, if a child has a different refraction in each eye or a disease which affects only one eye, the brain selects the image which is clearest, canceling out the vision of the worse eye.

What are the causes ?

The most frequent causes are strabismus and a difference in the refractive defect between both eyes. Other causes can be the appearance of congenital diseases or ones which appear during infancy, which impede correct visual development, such as congenital cataracts, opacity or scarring on the cornea, nystagmus etc…This eye impairment is often inherited.

How is it diagnosed ?

Very often parents do not realize that their child has a lazy eye, as the child does not appear to have any symptoms, seeing correctly as they do with the other eye. For this reason, ophthalmological check-ups for all children over the age of 3 or 4 are necessary, even younger if any symptoms are detected. In the case of children, special equipment is used to diagnose a lazy eye : a children’s vision scale, apparatus for examining the eyes, as well as personnel who specialize in carrying out these tests on children.

What treatment is there ?

The treatment and results will depend on the age of the patient and the ocular pathology which they have. The most classic treatment is the use of a patch to cover the good eye, so that the patient will use the lazy eye, thus stimulating the development of their eyesight. The ultimate objective is to recuperate maximum visual acuity and maintain this level of recuperation.

Is prevention possible ?

Ideally children should have an ophthalmological check-up at a young age, as early detection can optimize visual results to a great extent. Before the age of 4, the results which can be obtained are excellent, whereas after the age of 10 these results will be deficient. There is no solution for a lazy eye once a patient reaches adulthood.