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Eye Disorders

 

 

Disorders related to the Eye

  • Myopia

It is also known as​​ Nearsightedness or Shortsightedness. It is a condition in which the affected person can see nearby objects but is unable to see far away objects. It occurs when the eyeball is too​​ long, relative to the focusing power of the cornea and lens of the eye. This causes light rays to focus at a point in front of the retina, rather than directly on its surface. It is corrected by using​​ concave lense

  • Hypermetropia

Also known as​​ Longsightedness, it is condition in which the affected person can see distant objects but is unable to see nearby objects. It is corrected using​​ convex lens. Both Myopia and Hypermetropia are types of refractive errors of the eye.

  • Amblyopia

Also known as Lazy Eye, it is the loss of ability to see properly with one eye. Though the affected eye itself

looks normal, it is not being used normally because the brain is favouring the other eye. One of the causes of amblyopia may be Strabismus.

Presbyopia

Presbyopia is an​​ age-related eye disorder in which the eye is not able to focus light directly on to the retina due to the hardening of the natural lens. The ineffective lens causes light to focus behind the retina, causing poor vision for objects that are up close.

  • Glaucoma

Glaucoma refers to a group of related​​ eye disorders that all cause damage to the optic nerve that carries information from the eye to the brain.​​ Glaucoma usually has few or no initial symptoms. There is no cure for glaucoma and the vision lost cannot be​​ recovered.

  • Achromatopsia

Also known as Colour Blindness or Colour Vision Deficiency (CVD), it is the decreased ability to see colour or differences in colour. The condition is genetic and the genes responsible for it are on the X chromosome.

Hence more men are likely to be colour blind than women. The condition is diagnosed using the Isihara Colour Test. Other types of colour blindness -​​ Protanopia​​ or red-blind,​​ Deuteranopia​​ or green-

blind,​​ Tritanopia​​ or blue-blind

  • Cataract

A cataract is a​​ clouding of the eye's natural lens, which lies behind the iris and the pupil. The lens gets clouded due to protein present in it gets clumped together. Surgery replacing the natural lens with an artificial one can treat cataract.

  • Strabismus

Commonly known​​ as crossed-eyes. It is a disorder in which both eyes do not line up in the same direction, so they do not look at the same object at the same time. The condition is caused when the muscles controlling the eye do not function together.