In both cases, early diagnosis and treatment can prevent the eye problem from continuing into adulthood and, in the case of amblyopia, enables the sight in the "lazy eye" to be saved, which is not possible after childhood. Strabismus occurs when the eyes are not properly aligned with each other, resulting in each eye looking in different directions, causing an obvious eye deviation, which can be alternating (both eyes can wander at different times) and in any direction: inwards, outwards, upwards or downwards.
In some cases, the deviation is intermittent and more pronounced, when the patient is tired or feeling weak (in need of sleep at the end of the day, suffering from a fever, etc.). According to Dr Ana Wert, a paediatric ophthalmology specialist at the Instituto de Microcirugía Ocular in Barcelona, "this can make diagnosis more difficult, as it cannot be detected during the first visit to the ophthalmologist, so subsequent check-ups are very important, if the parents suspect anything."
Strabismus can occur during the first six months of life (congenital strabismus), during childhood and, in some cases, in adulthood, as a result of poor control of the movement of the eye muscles by the brain, a refractive error, low vision or a muscular abnormality.
The most serious consequence of strabismus is amblyopia, also known as "lazy eye". As the eyes are misaligned and point in different directions, the child’s brain, which has a great ability to adapt, suppresses vision in one of the eyes to prevent the abnormality and ensure the patient does not have double vision. As a result, one of the eyes is gradually used less and becomes "lazy" or amblyopic. Treatment of "lazy eye" is considerably easier the younger the patient is. The reason for this is that amblyopia occurs because the visual brain does not learn how to see, it has to be taught during infancy.