There are 3 layers to the eyeball: the sclera-the outer most layer, which is also known as the fibrous tunic, the choroid-the middle layer, which is also know as the pigmented tunic, and the retina-the inner layer, which also known as the visual tunic. The sclera is the white of the eye and is vascular. It is white in color because of collagen and is a continuous with the dura mater. The sclera is covered by a thin membrane called conjunctiva, the conjunctiva also lines inside of the eyelid. The choroid layer lies between the sclera and the retina. It is vascular and provides oxygen and nourishment to the retina. The retina is avascular. Light hitting the retina triggers nerve impulses which are sent to the brain via fibers of the optic nerve. Photoreceptors of the retina are rod cells-perceive light, and cone cells-perceive color. The Central fovea, a small indentation in the macula of the retina, is where cones are most concentrated and the area of most acute vision.
The eye has always been a wonder to me. Thanks to world of contacts I do not have to wear extremely heavy akward glasses. I was diagnosed with cataracts about 2 years ago. Cataracts are a clouding of the lens of the eye because of a build up of deposits. It is caused by a number of things-age, injury, congenital. I come from a long line of eye diseases and poor vision. I keep reading new ways that they treat this disease. From the advice of my Optometrist I look for the alternatives to laser surgery. I have thin corneas and he has advised that laser surgery would be dangerous. We are trying to hold off as long as possible before having the intraocular lens implanted because of my age and the likelihood of cataracts reoccurring. According to the Spokane Eye Clinic the cataract surgery has a 90% success rate of the patient recovering at least some of the lost vision. My optometrist says I should have vision in an eye that has never had anything other than a few shadows.
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I was in fifth grade and was waiting for my bus. It was spring time and the sand and dirt from the winter before when the roads were taken care of with. It was a very windy day in spurks and right before my bus came the wind blew and a small rock went in my eye and I rub it and my eyes started to hurt and get bury and water that the rock came out and I was still left with a bury and watering hurting eye. So I went to the doctor and they did test such as a stick of blue dye and then turned of the lights and found that I had torn my cornia and the doctor procribe antibotics by eye drops and told me to cover my eye with a patch to help it heal with out me constanly rubing it.
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