Double Vision – One Too Many: Cause or Effect?

You would not be alone if you thought Double Vision was simply a product of enjoying one too many on a Saturday night. If you’ve ever experienced it, you probably agree that seeing one too many is anything but enjoyable!

Double Vision is medically called diplopia, and what causes it, and what its effects may be, are a bit more complicated than you might have thought.

You can experience diplopia in one (monocular) or both eyes (binocular). Diplopia in both eyes is considered a more serious condition. Each of your eyes sees its own independent image; your brain combines the images into one clear picture. The muscles and nerves in your eyes, along with the lenses and cornea, all need to be healthy and working together for you to have clear vision. When there are issues with any of these essential parts of your eye, or if you’re experiencing issues with your brain, diplopia, can be one result.

Monocular Double Vision

The most common cause of monocular diplopia is nerve or muscle damage in one of your eyes. If you’ve ever experienced a temporary double vision from drinking alcohol, the alcohol is weakening your eye-muscle coordination and simultaneously slowing and impairing your brain function, causing temporary monocular diplopia.

It turns out that monocular diplopia is the less common, though less severe, of the two types, and can be caused by astigmatism, dry eye, keratoconus where the cornea becomes thin and cone-shaped, retinal abnormalities, or cataracts.

Temporary diplopia, the kind caused by intoxication or weakened eye muscles, can also be caused by excessive eye strain or exhaustion. When double vision is temporary, it’s generally not something to be worried about, but if normal vision doesn’t return relatively quickly, you will want to contact your eye doctor for a full examination.

Binocular Double Vision

Of the many possible causes of binocular diplopia, Grave’s disease, and Strabismus are particularly common. Grave’s disease is a thyroid condition that affects the eye muscles causing vertical double vision, where one image appears above the other. Strabismus is a weakened or paralyzed eye muscle that prevents the eyes from aligning properly, thus causing double vision.

Binocular double vision can also be caused by nerve damage resulting from diabetes, Guillain-Barre syndrome, multiple sclerosis, and other autoimmune diseases, or brain damage as a result of an aneurysm, brain tumor, migraine headaches, strokes, or head trauma.

Double Vision Diagnosis and Treatment

With so many possible causes of diplopia, both monocular and binocular, diagnosing the condition can be simple, but identifying the cause can be challenging. Treatment will depend on the underlying condition, as the symptom itself will only abate by addressing the root cause.

Surgery and/or medication can be used to treat many of the conditions that cause diplopia. Once the underlying condition is identified, your eye doctor will recommend a course of action to treat the root cause and simultaneously resolve the symptoms, including double vision.

If you or your child is suffering from a double vision that does not quickly resolve itself, you should contact your eye doctor immediately.

In children, you may notice behaviors like squinting or narrowing their eyes to see, covering one eye with their hand, turning their head in an unusual way, or looking at objects from the side rather than facing forward, all of which could indicate they are seeing double, and should visit the eye doctor as soon as possible.