Binocular diplopia is double vision, where people see two copies of the same scene, with equal quality, indicating that they are getting visual input from both eyes. This eye problem can be associated with a number of causes, including potentially dangerous medical conditions. People who develop double vision usually seek medical attention because it tends to be irritating and it is important to follow through on diagnosis and treatment. There are a number of options available for managing binocular diplopia, depending on the underlying cause of the condition.
Causes of binocular diplopia can include functional changes to the eye or brain. Sometimes, the eyes are physically misaligned or people develop strabismus, where the eyes are no longer evenly align with each other. Some congenital conditions pull the eyes askew, leading to double vision. These conditions may be diagnosed at or near birth, when a person's facial structure makes it readily apparent that the visual field probably contains a double image.
Damage to the nerves that supply the eye, including palsies, tumors, and lesions, can cause the eyes to pull out of alignment and may interfere with visual perception. Trauma to the head, causing damage to the eyes or brain, is also associated with double vision in some cases. In fact, problems with vision, including double vision or seeing stars, are a warning sign of brain damage in patients who have sustained head injuries, and people should always report changes in the visual field if they have recently received a blow to the head or any other kind of head injury.
Thyroid disorders like Grave's disease are linked with binocular diplopia, as is irritation to the eyes and the nerves and muscles that supply them. When a patient presents to a doctor for treatment of binocular diplopia, a thorough medical exam can be conducted to learn more about what the patient is experiencing and to identify some potential causes. Treatments can include medications, surgery, and visual exercises to retrain the eyes.
One thing to be aware of is that the human brain is a remarkably adaptable organ, and it is designed to compensate for conflicting or confusing visual information. Children with strabismus often do not experience double vision, for example, because their brains suppress visual input from one eye in order to streamline the child's visual perception. Thus, it is possible for people to have eye disorders associated with double vision without being aware of it.