Diplopia

diplopia

Diplopia is the medical term for seeing two images of a single object at the same time, commonly called double vision. There are two main kinds: one that remains when only one eye is open and one that occurs only when both eyes are open. Double vision in one eye usually stems from a problem inside that eye, such as an irregular cornea, lens issue, or retinal abnormality. Double vision that goes away when one eye is covered usually means the eyes are not aligned and both are sending different images to the brain. Misalignment can happen because the muscles that move the eyes or the nerves that control them are not working together, and causes range from fatigue or poorly adjusted glasses to nerve palsies, muscle entrapment after injury, thyroid-related eye disease, stroke, or myasthenia gravis. The direction and separation of the two images help clinicians identify which muscles or nerves may be involved. Evaluation includes covering each eye, testing eye movements, checking alignment, and sometimes imaging or blood tests to find an underlying cause. Treatment depends on the reason and may include temporary measures like patching or prism lenses, medications or injections to alter muscle strength, or surgery for long-term correction. Double vision can affect daily activities, driving, and depth perception, so prompt assessment is important for safety and the best chance of improvement.