Double Vision (Diplopia)

Double vision (diplopia) means that you are seeing one object as two images. The images may be seen side by side, up and down, or at an angle. There are two main types of double vision:

• Monocular. Only one eye is affected.

• Binocular. Both eyes are affected.

The best way to tell the difference is to close one eye at a time. If the double vision goes away when you close one eye, it's binocular double vision. If it does not go away, it is monocular double vision. Most monocular double vision is caused by certain diseases inside the eye. Most binocular double vision is from conditions outside the eye, usually related to the eye muscles. There are many causes for double vision, including:

• Disease inside the eye (monocular).

• Problem with the muscles and nerves that control the movement of the eye (binocular).

• Injury to the eye or bones around the eye (binocular).

• Past surgery around the eye (binocular).

• Disease in the brain (binocular).

More testing is needed to figure out the cause of your double vision. Because a serious disease may be present, it's important to follow up as advised.