Diplopia (Double Vision)
Vision disorders are conditions which cause impairment of vision. These disorders are often caused by certain eye diseases or structural abnormalities of the eye balls.
Double vision also called diplopia is a condition in which the patient complains of being able to see two images of a single object. There are two forms of double vision—monocular and binocular diplopia. Monocular diplopia occurs when there is double vision in one of the eyes only and double vision continues even if the other eye is closed. It is caused by conditions such as abnormal curvature in the front surface of the cornea (astigmatism), cone shaped cornea (keratoconus), thickening of the conjunctiva (pterygium), cataract, dislocated lens, a mass or swelling in eyelid, and dry eyes. Binocular diplopia is caused by misalignment of the eyes and in this type, double vision resolves if either eye is covered. It is because of problems in one or more muscles that surround the eye and control the direction of gaze. These problems include strabismus, nerve damage, diabetes, myasthenia gravis, Graves’ disease or trauma to the eye muscles.