What is Myopia?

About Myopia:

• Myopia, also known as nearsightedness, is an eye condition that causes blurry distance vision.
• People who are nearsighted have more trouble seeing things that are far away (such as when driving) than things that are close up (such as when reading or using a computer).
• What causes Myopia?
  • For normal vision, light passes through the clear cornea at the front of the eye and is focused by the lens onto the surface of the retina, which is the lining of the back of the eye that contains light-sensing cells.
  • People who are nearsighted typically have eyeballs that are too long from front to back.
  • As a result, light entering the eye is focused too far forward, in front of the retina instead of on its surface.
  • It is this change that causes distant objects to appear blurry.
  • The longer the eyeball is, the farther forward light rays will be focused and the more severely nearsighted a person will be.
  • Eye experts are still unsure of the exact cause of myopia, but believe it to be a mix of hereditary and environmental factors.
• Nearsightedness usually begins in childhood or adolescence. 
• It tends to worsen with age until adulthood, when it may stop getting worse (stabilize). In some people, nearsightedness improves in later adulthood.
• Symptoms: Nearsightedness can lead to squinting, eyestrain, headaches, and significant visual impairment.
• Treatment:
  • Glasses or contact lenses can correct myopia in children and adults.
  • For adults only (with rare exceptions for children), there are several types of refractive surgeries that can also correct myopia.
  • Negative (minus) powered lenses are used to correct nearsightedness.

Q1: What is cornea?

The cornea is the clear tissue covering the front of your eye. Cornea serves as a protective window that allows light to enter your eye and come to focus on your retina. The cornea must remain clear for you to have good vision. 

Source:  Outdoor activities can reduce ‘progression of myopia’