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Blindness

• Overview
• Treatment

Definition:

Blindness is a lack of vision. It may also refer to a loss of vision that cannot be corrected with glasses or contact lenses.

• Partial blindness means you have very limited vision.
• Complete blindness means you cannot see anything and do not see light.

People with vision worse than 20/200 are considered legally blind in most states in the United States.

Alternative Names:

Loss of vision

Common Causes:

Blindness has many causes. In the United States, the leading causes are diabetes , glaucoma, macular degeneration , and accidents (such as chemical burns or sports injuries).

Worldwide, the leading causes of blindness are cataracts, onchocerciasis (river blindness), trachoma, leprosy, and vitamin A deficiency .

Other causes include:

• Blocked blood vessels
• Complications of premature birth ( retrolental fibroplasia )
• Complications of eye surgery
• Lazy eye
• Optic neuritis
• Stroke
• Tay-Sachs disease
• Retinitis pigmentosa
• Retinoblastoma
• Lead poisoning
• Optic glioma

• Review Date: 2/22/2007
• Reviewed By: Manju Subramanian, MD, Assistant Professor in Ophthalmology, Vitreoretinal Disease and Surgery, Boston University Eye Associates, Boston, MA. Review provided by VeriMed Healthcare Network.

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