Signs and Symptoms
Blindness is defined by the World Health Organization as vision in a person's best eye of less than 20/500 or a visual field of less than 10 degrees. This definition was set in 1972 and there is ongoing discussion on if it should be altered somewhat.
Read more about this topic: Blindness
Famous quotes containing the words signs and, signs and/or symptoms:
“But I will harden Pharaoh’s heart, and I will multiply my signs and wonders in the land of Egypt.”
—Bible: Hebrew, Exodus 7:3.
“One of the signs of passing youth is the birth of a sense of fellowship with other human beings as we take our place among them.”
—Virginia Woolf (1882–1941)
“Not being a K.N. [Know-Nothing] I am left as a sort of waif on the political sea with symptoms of a mild sort towards Black Republicanism.”
—Rutherford Birchard Hayes (1822–1893)