Night Blindness :: essays research papers

Night Blindness is a genetic distemper in which the sufferer has trouble perceive at night. Two things cause this put disclose in general. The first cause is a lack of vitamin A which helps germinate the retina and vision receptor cells. Vision receptor cells consist of cones and rods, cones for bright come and rods for less fairylike. When there is a vitamin A deficiency, the rod cells dont develop properly. The second cause is a genetic inheritance. Night blindness is a sex-linked disorderliness because the X-chromosome was found to be different than conventionality in people with the disorder.There are many vision-related effects this disorder can have on a person. In most cases, the person isnt completely blind in disconsolate areas, but sees things a lot darker than they really are. In other cases, it takes the persons eye much longer than normal to adjust to different light settings. For example, if a person with night blindness suddenly has the lights turned off in front of them, it may be up to 10 minutes in advance they can see anything at all. Also, the same thing happens when going from dark to light. The sufferer will see extremely bright images when flooded with light after having adjusted their eyes to darkness.There are many words for night blindness that exist today. The most common treatment is taking vitamin A supplements to restore the vitamin A that helps develop and maintain the retina. Also, zinc supplements can be taken as well to further strengthen the retina. Physical forms of treatment include lasers, freezing, injection of gas into the eye, scleral buckling, and removal of the gel inside the eye.This disorder is usually accompanied by shortsightedness (nearsighted). About half of teenagers with myopia will develop some form of night blindness. These cases start out around the age of fifteen. Also, about 52% of women said they had trouble seeing at night during their last pregnancy.