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Essay On Human Eye Structure

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3.BASICS OF DIABETIC RETINOPATHY I.Human Eye Structure
Light enters the eye through the pupil then it is focused on the retina. The lens helps in focusing images from different distance. The iris controls the amount of light entering the eye, as the intensity of light increases iris closes when light intensity decreases iris opens. Conjunctiva is transparent white sheet for the outside world. The focusing of lens automatically is controlled by ciliary muscles in ciliary body. Choroids form the vascular layer of the eye. It supplies nutrition to the eye structures. Optic nerve transmits image formed on the retina to the brain. No other part in retina image is as bright as optic disc is and Optic disc is circular in shape. It also acts as the entry and exist point for nerves entering as well as leaving the retina to and from the brain. The oval shape object near to the centre of the retina is called macula. The space near the centre of the macula is occupied by fovea and it contains packed cone cells. The fovea is responsible for the most accurate vision because of high amount of light sensitive cells.

Fig: Human Eye Structure …show more content…
There are mainly two types of diabetic retinopathy they are non proliferative and proliferative. The Non proliferative diabetic retinopathy is the early stages of the disease. It fevers blood vessels in the eye retina which leads to blurred vision for fluid leaks.Proliferative retinopathy disease is more serious and more advanced and they are the new blood vessels in the eye of human. A.Proliferative diabetic retinopathy

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