Double Vision and Its Causes and Diagnoses

If you have double vision, that is, seeing two images of one object, you may find the defect disappears when you close one of your eyes.

However, you should consult your doctor immediately if you suddenly start to experience double vision because it may indicate that you have a serious underlying disorder.

Causes of Double Vision

• The most common cause of double vision is weakness or paralysis of one or more of the muscles that control the movements of one eye.
• Many serious conditions that affect the brain and nervous system may cause impaired eye movements leading to double vision. Potential causes include multiple sclerosis, head injuries, brain tumours and bulging of an artery inside the head due to a weakness in the vessel wall (aneurysm).
• In older people, impaired eye movement resulting in double vision may be linked to diabetes mellitus, and, rarely, to atherosclerosis and high blood pressure.
• Double vision can also occur as a result of a tumour or blood clot behind one of the eyes, causing the movement of that eye to be affected.

Diagnosed of Double Vision

• Your doctor may ask you to shut one eye at a time to see whether the double vision disappears.
• Your doctor will probably observe the movements of your eyes closely in order to establish whether any of the eye muscles are weak or paralyzed and do special vision tests to identify weak eye movement.
• If double vision has come on suddenly, or if no obvious cause can be found, urgent computerized tomography (CT) scanning or magnetic resonance imaging (MRI) may be done to check for any abnormality in the eye sockets or brain that might be affecting the alignment of the eyes. You may also have a neurological examination.