Causes of Double Vision or Diplopia

There are two possible and different causes:

  • The most common cause of double vision is misalignment of the two eyesdue to functional problems in the visual system – binocular diplopia.
  • A structural defect in the eye’s optical system is a much less common cause of double vision. Cataracts, for example, might cause such a defect. In this case, diplopia can appear in only one eye; this is called monocular diplopia.

Double vision can be a symptom of many different visual conditions that affect children and adults, such as strabismus, convergence insufficiency or visual conditions related to head injuries.

What is Double Vision? (Binocular Diplopia)

If the two eyes are misaligned either since birth or acquired, and aim at different targets, two non-matching images will be sent to the viewer’s brain. When the brain accepts and uses two non-matching images at the same time, double vision results.In an attempt to avoid double vision, the brain will eventually disregard one of the mismatching images causing suppression.This type of adaptation occurs mainly in children.The adult brain cannot supress the double images and are often incapacitated by this symptom.

Sudden Double vision is not a minor complaint. It can be the first symptom of an intracranial pathology (tumour, trauma or due to uncontrolled diabetes and hypertension) or myasthenia gravis.

Neurological cases of diplopia

Stroke, head injury, brain tumor, brain swelling or brain aneurysm. A head injury, tumor, stroke or related condition can cause double vision that comes on suddenly.

Cranial nerve palsies. Double vision also can be caused by paralysis or loss of coordination of one or more muscles that control the position and teaming of the eyes due to cranial nerve palsy. Cranial nerve palsies can be caused by viral fever diabetes, head injury, tumor, multiple sclerosis, meningitis, high blood pressure, blockage in an artery or an aneurysm.

Treatment

  • Identify and treat the underlying cause. This may include complete haematological work up and imaging.
  • Prism glasses and orthoptic exercises
  • Surgery