Vision loss, or a reduction in eyesight, is a symptom that involves a reduction or loss of a person’s ability to see. It can range from having blurred or double vision to compete blindness. The impairment can be temporary or permanent, and may occur suddenly or develop over time. The type of vision loss experienced depends on its cause.

A wide variety of conditions can cause vision loss. These include physical injuries to the eye, eye disorders or diseases, certain medical conditions (e.g., diabetes) and genetic disorders. Certain infections and adverse side effects from some medications may also cause vision loss.

Neurological causes of vision loss typically involve damage, disease or disorder of the optic nerves (one of the 12 pairs of cranial nerves) or parts of the brain associated with eyesight. A variety of neurological diseases can cause this type of damage, including:

• Head injury
  
  
• Brain tumors
  
  
• Interruption in flow of blood and oxygen to the brain (e.g., stroke)
  
  
• Cranial blood vessel problems (e.g., cerebral aneurysm)
  
  
• Optic nerve problems (e.g., inflammation associated with multiple sclerosis)

A number of additional symptoms may accompany vision loss, depending on the cause. Dizziness and a loss of balance are the most common symptoms that occur with vision loss. Ataxia, eye pain and headaches may also occur.

Treating vision loss involves treating its cause. Treatments that may be used for neurological causes of vision loss include medications and surgery. However, vision loss due to brain or nerve damage often cannot be reversed. In these cases, treatment often focuses on controlling a patient’s symptoms and developing skills to adapt to vision loss. A number of treatment methods may help, including specialized training and use of mobility aids and/or voice-generating devices.

In many cases, vision loss cannot be prevented. This is especially true for vision loss that results from neurological causes. However, when vision loss is caused by a preventable condition, taking steps to avoid developing the condition may be advisable in order to preserve vision.