Strabismus is a very common eye problem, consisting of a persistent or occasional deviation of one or both eyes. It can appear before six months of age—known as congenital strabismus—during childhood, or, in some cases, in adulthood, due to poor control of eye muscle movement by the brain, a refractive error, low vision, or a muscular abnormality, and, more recently, due to excess eye movement. Although early diagnosis and treatment of strabismus are most advisable so that it does not affect visual development in childhood, Dr. Ana Wert, an ophthalmologist specializing in strabismus at the IMO Grup Miranza, explains that adult patients should not resign themselves to living with this problem.