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What Causes Blindness

May 10, 2017

Blindness is a debilitating eye disease. It is the inability to see anything, even in the light or light itself.

There are several different types of blindness that are important to recognize:

  • Partially Blind –  having limited vision. This includes having blurry vision or the inability to distinguish objects.
  • Complete Blindness – this means you can’t see at all and are in complete darkness.
  • Legal Blindness – is vision that is highly compromised. For example, a person with healthy eyes can see up to 200 feet away, but someone who is legally blind can only see 20 feet away.

So what causes blindness? Blindness can be caused by eye diseases–less than 4 percent of blindness are caused by eye injury or trauma. There are four types of conditions that cause blindness:


  • Cataracts – Cataracts occur when the crystal clear lens of your eye becomes cloud. This results in blurry vision, faded colors and seeing through glare. Cataracts are the world’s number one cause of blindness, which increases in numbers as a person ages. .
  • Glaucoma – This condition mostly happens when fluid pressure inside one or both eyes slowly begin to increase. The pressure then damages the optic nerve and the retina causes a decrease in peripheral vision. Most vision loss due to glaucoma cannot be reversed, but this disease is manageable through prescription eye drops and/or surgery. It is vitally important to have regular eye exams to catch glaucoma early.
  • Macular Degeneration – This disease involves the gradual deterioration of the macula, or the nerve endings in the retina that are vital for sharp central vision. Although there is no cure for macular degeneration, treatments such as vitamin therapy, laser surgery, and special medications help to slow its progress.
  • Diabetic Retinopathy – When the systemic damage caused by diabetes begins to affect the retina, diabetic retinopathy occurs. It is specifically caused by the blood vessels, which nourish the retina, being negatively affected by diabetes. This causes vision loss through bleeding and direct damage to the retina. The most reliable treatment for this is close control of diabetes. If it is, however, more advanced than those affected can undergo eye surgery to further protect their sight.

Always remember to seek medical attention if suddenly you lose the ability to see, and never wait for your vision to return. Depending on the cause of your blindness, immediate treatment can increase your chances of restoring your vision.