Passage of Time: Many people have a hidden • Botulinum toxin (Botox) injections misalignment of the eyes that is well into the eye muscles, causing them controlled (phoria) most of their lives to remain relaxed (longstanding) which can decompensate later • Surgery on the muscles of one or causing intermittent or constant diplopia. both eyes to correct their positioning • Medications can help if diagnosed Other symptoms? with diabetes or myasthenia gravis

Double vision often occurs with no other symptoms, but depending on the underlying Coping with Diplopia cause, other symptoms may be present, such as: What is diplopia?

• Pain when moving one or both eyes Diplopia, or double vision, occurs when • Discomfort or pain around the eyes, Patching one eye someone sees two images of a single object. such as in the temples or eyebrows This vision problem can occur constantly or • Drooping eyelids intermittently, depending on the severity • Headache and underlying cause. • Nausea There are three different types of diplopia: How is diplopia treated? • Binocular diplopia – both eyes do not Double vision is treated by first identifying Prism applied to one lens (Fresnel press-on line up together as they should, and the underlying cause. If the problem does prism) or ground into one or both lenses only one image remains if you cover not resolve, there are treatments to help either eye people manage and live with double vision: • Monocular diplopia – double vision is present in one eye when the other is • A head posture to fuse images covered. The double image may look • Prescription glasses/contacts ghosted only slightly separated • Eye exercises (ie. for convergence • Physiological diplopia – this is insufficiency) Fog all or part of an eye with contact paper, actually normal, but not usually • Fresnel press-on prisms or ground-in Bangerter filter, or a Min occlusion lens noticed. Images behind (or in front prisms in glasses to optically align of) the object being viewed appear the two images into one double. • An eye patch or opaque contact lens • Fog part or all of one lens in glasses www.orthoptics.org astigmatism, keratoconus, other refractive • Graves’ disease or thyroid eye errors or by dryness. Corneal damage can be disease, an auto-immune disorder caused by injury or infection. Glasses, contact that affects eye muscles and can lenses or dry eye treatment may be helpful in cause eyelid stare (retraction) and treating some types of monocular diplopia. diplopia.

If the two eyes have different refractive • Myasthenia gravis, also an Horizontal Vertical Diagonal Note: The two images can be close or far apart. powers (anisometropia) the images may be autoimmune disease, interrupts the They can also be tilted (torsional.) different sizes and may cause diplopia. message from the nerve to the muscle. Early signs include diplopia Pupil: This is an opening in the iris or colored and ptosis (drooping eyelids.) part of the eye and looks black. It can vary in size in response to light or focusing at near. Nerves: These carry information from the brain to your eyes. If the nerve is damaged or Lens: This sits behind your pupil and helps weak, it cannot tell the muscle to contract, focus light onto your retina. Lenses can and usually causes double vision: become cloudy (cataracts) or even dislocated. Early cataracts may cause monocular diplopia. • Diabetes or high blood pressure is a Retina: This is the light-sensitive layer at the common cause of nerve damage to back of your eye and should be perfectly the muscles that move your eyes. • Injury to the head or orbit (eye The Eye and Extraocular Muscles smooth. Diplopia can occur when the retina is disrupted, as with retinal detachment, socket) often causes nerve damage epiretinal membrane, macular hole or (palsy) and diplopia. macular edema. • Multiple sclerosis (rare) can affect What causes diplopia? nerves anywhere in your brain or Muscles: Six muscles attached to each eye spinal cord. When you see double, there is a problem allow the eyes to move in certain directions. with eye coordination or the optical system. The movements are coordinated by the brain. Brain: The nerves that control your eyes To understand what can go wrong, it helps to When a muscle in one eye is weak the eyes connect directly to your brain where images know the parts of your eye and how the eyes do not work together and may cause diplopia, are processed. Many causes of double vision work together. especially when looking in the direction of start in the brain. They include: action of a weak muscle. The eye muscles Cornea: The clear window into your eye. Its may be affected by: • Strokes or aneurysms main job is to focus light. If your double vision • Trauma, bleeding, infection or doesn’t go away when you cover one eye • A problem with the nerves or brain increased pressure inside the brain (monocular diplopia) the rays of light entering centers that control them. • Brain tumors the eye are being split. This may occur if the • Inflammation or direct injury • Parkinson disease shape of the cornea is altered or damaged by • Migraine headaches