Eye Defects: Myopia, Introduction to Eye Defects, About Myopia (For CBSE, ICSE, IAS, NET, NRA 2022)

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Eye Defects: Myopia

Introduction to Eye Defects

  • The human eyes gradually lose their power of accommodation. In such cases, the person cannot see distinctly and comfortably.
  • There are three common eye defects and they are
    • Myopia or near-sightedness
    • Hypermetropia or farsightedness
    • Presbyopia
  • These defects are corrected by the use of suitable spherical lenses.

About Myopia

About Myopia

The Structure of Your Eye is Too Blamable

  • When Your Eyeball is Too Long or the Cornea - the Protective Outer Layer of Your Eye - is Too Curved, the Light That Enters Your Eye Won՚t Focus Correctly.
  • Images Focus in Front of the Retina, the Light-Sensitive Part of Your Eye, Instead of Directly on the Retina.
  • This Causes Blurred Vision.
  • Doctors Call this a Refractive Error.
  • Myopia is Also Known as Nearsightedness or Shortsightedness.
  • What Happens Here is That Light Rays Do Not Focus on the Surface of the Retina but in Front of It.
  • These Results in Images Being Blurry when Perceived. in Such a Case, Distant Images Appear Out of Focus but Objects Nearby Are Seen Clearly.
  • Therefore, Myopia is Also Called Near or Shortsightedness.
  • It Can Occur if the Eyeball is Elongated Leading to Image Formation in Front of the Retina. It Can Also Occur if the Refracting Power of the Lens is Affected Due to the Cornea or Lens Being Too Curved.
  • This Effect Can Be More Pronounced with Age. a Combination of These Effects Will Also Lead to Myopia.

Types of Myopia

High Myopia

  • It՚s a very serious form of the condition, where the eyeball grows more than it is supposed to and becomes very long front to back.
  • Besides making it hard to see things at a distance, it can also raise your chance of having other conditions like a detached retina, cataracts, and glaucoma.

Degenerative Myopia

  • It is also called pathological or malignant myopia; it is a rare type you usually inherit from your parents.
  • So, eyeball gets longer very quickly and causes severe myopia, usually by the teenage or early adult years.
  • This type of myopia can get worse far into adulthood.
  • Besides making it hard to see things at a distance, you may have a higher chance of having a detached retina, abnormal blood vessel growth in the eye (choroid neovascularization) , and glaucoma.

Correcting Myopia

  • It is important to remember that Myopia is an eye defect and not an eye disease.
  • So, it can be corrected. Since the image is formed in front of the retina, correcting this problem can counter the effects produced due to this.
  • The treatment of myopia consists of managing both the visual acuity loss and the complications that may arise.
  • Treatment of the blurred vision in myopia has had a long and checkered history.
  • Everything from physical exercise to palming the eyes to having myopic students՚ study in green rooms has been advocated at one time or another.
  • Sight-saving classes, exercises, under-correction, cycloplegic therapy, contact lenses, pinhole glasses, and many other therapies have been aimed at preventing or slowing the progression of myopia.
  • Surgery has been advocated to retard the progression of staphylomas in pathological myopia. A few of these therapies deserve mention.

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