Double vision, also known as diplopia, is the simultaneous perception of two images of a single object. The displacement of the image may be horizontally, vertically, or diagonally and should not be confused with blurred vision, which is when an individual sees a single unclear image.
Patients may find they have double vision occasionally, or in other cases, all of the time. Temporary double vision may be caused by alcohol intoxication, concussions, tiredness, or a side effect to certain drugs. Permanent double vision requires deeper investigation as there are two major types of double vision, binocular double vision and monocular double vision. Let’s take a closer look at both.
Binocular double vision is when a patient’s eyes are not perfectly aligned. In other words, the eyes point at slightly different angles, resulting in different images being sent to the brain. The brain does not recognize the images to be similar enough to create a single, clear image, so it creates two images. Binocular double vision is most often caused by a squint due to a weakened or paralyzed eye muscle. Other causes of binocular double vision may be thyroid disease, arterial disease, diabetes, myasthenia gravis, multiple sclerosis, an aneurysm, blood clots, a stroke, cancer, or head injury.
Monocular double vision is less common than binocular double vision and is caused by abnormalities to parts of the eye including the cornea, iris, lens, vitreous humor and aqueous humor. Astigmatism, cataracts, dry eyes, swelling in the eye lids, or a dislocated lens usually result in monocular double vision.Whether it be occasionally or often, it’s important to see your optometrist to diagnose the issue. We encourage you to give us a call at 814-234-6060 to set up an appointment to discuss tests and treatment options that will have you seeing clearly again.