This depends on each particular case, the type of strabismus, the vision in each eye, your eye surgery history and any underlying pathology… Approximately 30-40% of patients who undergo strabismus surgery will require more than one operation. The reason this figure is so high is because, in the majority of cases, the brain of the strabismus patient does not have the capacity for binocular vision (the ability to maintain visual focus with both eyes), which is a contributing factor to correct eye alignment.