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Astigmatism is a common type of mild optical defect. This optical defect is a kind of asymmetric refractive error which blurs your vision at near and far visual space. Definition of astigmatism is: Lens visual asmmetry or lens irregular diameters. In other words, astigmatism appears when external layer of your eyeball known as cornea or lens is not round but like egg-shaped or rugby ball. The eye is formed as two parts. First part is the cornea and second part is the lens. The back of eye is named as retina. When you want to see something you look at it. Meanwhile, your cornea and lens both focus on that object. While you are looking at the image, the light on the object is reflected to your eye. Then, your eye immediately focus on the reflected light and turns or refracts it into teeny-weeny electrical impulses. Spontaneously, these electrical impulses are transmitted to the brain with the help of neural transmission of optic nerve. Thus, in reality you see things in your brain. This is because vision or visual perception depends on light. An eye without optical defect has a perfect curvature and round-shaped as a smooth and soft ball. A well-curvatured cornea or lens can refract reflected light flawlessly. However, an eye with optical defect has an imperfect curvature like as egg-shaped or a rugby ball. A misshaped cornea or lens cannot refract incoming light flawlessly. This optical defect causes a refractive error. In astigmatism there are two forms. If refractive error occurs in cornea due to its deformation it is corneal astigmatismIf refractive error occurs in lens due to its deformation it is lenticular astigmatism. Corneal astigmatism and lenticular astigmatism both may be reason of blurred vision. This visual impairment is generally genetous.

Apart from this, it may arise after eye diseases, injuries, operations and also high eye pressure or intraocular pressure changes. However, this type of poor vision is not because of reading in poor or bright light, watching television too close or squiting named in medical term as strabismus or strabism. Therefore, you should have a visual test for astigmatism. Besides, visual tests for your children may be the best choice in their babyhood, childhood and puberty because of both their eye health and success in school. The signs and symptoms of astigmatism are: Blurred or cloudy vision, eye pain, eyestrain and recurrent headaches. Sometimes, astigmatism may come into existence with other refractive errors as myopia or hypermetropia. The optical term myopia is used for nearsightedness or shortsightedness. Besides, the optical term hypermetropia is used for rarsightedness or longsightedness. Astigmatic, myopia and hypermetropia are not severe visual impairments. They only cause people with poor vision. In order to correct poor vision an eye doctor called oculist may clarify whether it is astigmatism. If so, he/she try to find out to what degree it is. To confirm the presence of astigmatism, ophthalmologist measures reflected light from the outer surface of the cornea and also the curvature of the cornea. Treatment of astigmatism is to wear corrective lenses or having a refractive surgery. To wear corrective lenses help to treat astigmatism by cancel out the asymmetrical curvature of the cornea. Corrective lenses are eyeglasses and contact lenses. Wearing corrective eyeglasses or prescription glasses can not only correct astigmatic but also myopia and hypermetropia. Those who do not wish to wear eyeglasses can prefer to wear corrective contact lenses. They can take eye doctor’s advice about the pros and cons of all kinds of contact lenses as bifocal, disposable, extended wear, hard, permeable, rigid gas and soft. If reactive surgery is preferred, the techniques are: Photorefractive keratectomy, Laser-assisted subepithelial keratomileusis and LASIK surgery.

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