Visual Perception Deficit: Cataract and Glaucoma

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Liceo de Cagayn university – graduate studies | Visual Perception Deficits | Cataract & Glaucoma | Submitted by: | Nadine Angelica C. Gadia – Casiño, RN | March 18, 2012Submitted to:Ms. Delia V. Realista, RN, MANProfessor |

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I. Intoduction
Cataract
Cataracts are common and significant cause of visual defects all over the world. A cataract is an opacification or clouding of the lens of the eye. Cataracts develop because of the alteration of transport of nutrients and metabolism in the lens. This interferes with light transmission to the retina therefore affecting the ability to perceive images clearly. All cells of the lens formed in the lifetime is retained therefore prevalence of cataracts increase rapidly with aging.
WHO estimates that cataracts account for 48% of reversible blindness worldwide, which translates to about 18 million people. Cataracts affect slightly more women than men. The Beaver Dam Eye Study in the US found that 23.5% of women and 14.3% of men had a visually significant cataract by the age of 65 years. Although cataracts can be surgically removed, in many countries surgical services are inadequate, and cataract remains the leading cause of blindness.
Age is the greatest risk factor in the occurrence of cataracts. Cataract, though with unclear links, may be acquired through heredity and genetics (e.g., Wilson's disease, galactosaemia, myotonic dystrophy). Early formation of cataracts is associated with the following risk factors: * Environmental and lifestyle factors such as long term exposure to glares (e.g. welding) and sunlight, smoking and heavy alcohol consumption * Diabetes mellitus particularly in patients with poor control of blood glucose. * Long-term use of corticosteroids
With the clouding of the lens light rays scatter as they pass through thus decreasing visual acuity. There are complaints…...

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