Are you having problems with night vision? Millions of Americans do. Poor night vision may simply be an early sign of progressive cataracts. Problems with night vision -- or at the extreme, night blindness -- may be treatable or could be a sign of a congenital problem such as retinitis pigmentosa or other more serious conditions.
Amblyopia: Also known as "lazy eye," amblyopia is a condition that starts in childhood in which vision has not developed properly in one eye or the other. If amblyopia is left untreated, a child's vision will not develop correctly, and as the brain matures, one eye will remain with poor vision.
Aqueous humor: The clear, watery fluid between the lens and the cornea.
Astigmatism: A condition in which blurred vision is caused by the cornea being shaped more like a football than spherical like a basketball. Astigmatism may be compensated for through eyeglasses or contacts, or it can be corrected through refractive surgery.
Beta-blocker: A medication used in the treatment of glaucoma, beta-blocker eye drops help reduce the pressure within the eye by reducing the production of aqueous humor.
Carbonic anhydrase inhibitor: A type of medication used to treat glaucoma. Carbonic anhydrase inhibitors work by reducing the production of aqueous humor, thereby reducing pressure inside the eye.
Choroid: The layer of blood vessels between the retina and the sclera.
Choroiditis: A form of uveitis that causes an inflammation of the layer beneath the retina. It may also be caused by an infection such as tuberculosis.
Conjunctiva: A thin layer of tissue that lines the inside of the eyelids as well as the outer surfaces of the sclera.