Search results
Results from the WOW.Com Content Network
Leber congenital amaurosis can cause total blindness or severe sight loss from birth or early childhood. Retinitis pigmentosa is characterized by decreased peripheral vision and trouble seeing at night. Advances in mapping of the human genome have identified other genetic causes of low vision or blindness.
While it is caused by bright light similar to flash blindness, the welder's arc lasts for much longer than flash blindness and involves exposure to ultraviolet rays that can damage the cornea. Flash blindness, in contrast, is caused by a single, very brief exposure which oversaturates the retina, and is not usually accompanied by reports of pain.
Corneal opacity is the 4th main cause of blindness globally (5.1%). [1] Using the World Health Organization's (WHO; Geneva, Switzerland) blindness definition,1 45 million people worldwide are bilaterally blind, of which 6 to 8 million are blind due to corneal disease. In some African areas, nearly 90% of the total blindness is due to corneal ...
Cortical blindness is the total or partial loss of vision in a normal-appearing eye caused by damage to the brain's occipital cortex. [1] Cortical blindness can be acquired or congenital, and may also be transient in certain instances. [ 2 ]
Like a magnifying glass, lenses in the human eye focus light on the back of the eye to create a clear image. But if you look directly at the sun, that focused light can burn your eye – and the ...
CVI is also sometimes known as cortical blindness, although most people with CVI are not totally blind. The term neurological visual impairment (NVI) covers both CVI and total cortical blindness. Delayed visual maturation, another form of NVI, is similar to CVI, except the child's visual difficulties resolve in a few months.
It is the cause of approximately 5% of blindness in the United States and nearly 60% of blindness in parts of Africa and South America. [12] Blindness from cataracts occurs in about 10 to 40 per 100,000 children in the developing world, and 1 to 4 per 100,000 children in the developed world. [7] Cataracts become more common with age. [1]
Blue cone monochromacy (BCM) is an inherited eye disease that causes severe color blindness, poor visual acuity, nystagmus, hemeralopia, and photophobia due to the absence of functional red (L) and green (M) cone photoreceptor cells in the retina. BCM is a recessive X-linked disease and almost exclusively affects XY karyotypes.