A clouding of the lens which causes a general loss of detail in what a person sees. The field of vision is unaffected, but glaring light conditions, distortion, and double images can prove annoying. A disease where tissues are damaged by increasing pressure inside the eye. Characterized by night blindness, retinitis pigmentosa frequently results in tunnel vision. Central vision can also be affected.
Retinas detach for a variety of reasons and many can be surgically repaired.
When active, the hole or tear involved fills with liquid, lifting the retina from its normal position, and causing a defect in the field of vision. These can appear as dark shadows, either above or below the central field, as though a hanging curtain or wave was obstructing vision. Most commonly, some vision remains intact. BACK TO THE TOP 5. A 1977 governmental health survey estimates that there are approximately 11.