Double Vision in One Eye

Also medically termed as 'diplopia', double vision is a major concern that should not be taken for granted. This medical disorder of the eyes, causes the affected person to see two or double images of the same object, and this may happen occasionally or all the time.

Double vision occurs when the eyes have 'converged' for near objects and are not correctly aligned for viewing distant objects. In this condition, the eyes cease to work as a pair and lose their alignment with each other. What happens ultimately is, the brain remains unable to fuse the two images that have been produced. Double vision can occur in one eye also; known as 'monocular diplopia'. This happens due to one or more defects in the structure of the eye's optical system. Episodes of temporary double vision can occur from excessive drinking of alcohol or extreme fatigue. Such cases are usually not of concern unless, the double vision becomes long-lasting or keeps recurring.

Causes of Double Vision in one Eye

Astigmatism is one of the causes of monocular diplopia . It is defined as a visual disorder or an optical defect where in, the vision of the affected person gets blurred. Here, the optics of the eye is unable to form a sharp image of a point object on the retina. Astigmatism occurs due to misshapen cornea or lens and it is a more complex disorder with complex variations, than myopia or hypermetropia.

Cataract is the most common eye problem which people come up with. It is one of the lens problem that is responsible for causing double vision. A person suffering from a cataract will notice his eye's lens getting cloudy, affecting his vision.

Problems in the cornea such as infection or complication caused by LASIK eye surgery, are the common causes of double vision on one eye. Due to such complications, the damaged surface of the eye distorts incoming light and causes double vision in one eye. Another disorder of the cornea is keratoconus that leads to monocular diplopia. It is an uncommon degenerative eye disorder, where in the cornea keeps on becoming thinner. It attains the shape of a cone and this ultimately affects the vision. Pterygium is also responsible for causing double vision in one eye. It is again a disorder that is related to the cornea. It is diagnosed by pinkish, triangular-shaped tissue growth on the eye's cornea.

Weak muscles of the eye may also not allow the affected person to have a single and clear vision of objects. If the muscle of one eye is weak, then it becomes difficult for this eye to move smoothly with the healthy one. This causes gazing in directions controlled by the weak muscle, and eventually leads to double vision in the eye. Some of the common causes of muscle weakness result from myasthenia gravis ( an autoimmune illness) and Grave's disease (thyroid condition). Grave's disease weakens the eye muscles and causes image to form on top of the other. This is known as vertical double vision in one eye.

Diabetes usually damages the nerves in one of the eyes and may cause double vision in one eye. Other causes are nerve problems such as multiple sclerosis and Guillain Barre syndrome. The brain is where the images are formed. Severe medical cases that involve the brain are also directly related to the occurrence of double vision in one eye. Migraines, brain tumors, strokes, aneurysms and any trauma to the brain are some of the causes.

Sudden double vision in one eye or in both the eyes may indicate some underlying and severe illnesses, such as brain tumors or aneurysms. Here, if a person has a sudden monocular diplopia, it may go away for over a long time. However, it is not at all a good sign and should immediately be reported to an eye doctor, on its occurrence.

Treatment of double vision in one eye is generally done with the help of medications or surgery. In some cases, if the causes are delt with properly, then also, this disorder can be countered with. For some people, double vision cannot be reversed or cured completely. For them, treatments can help in reducing its effect and discomfort to an extent.