Myopia — commonly called short-sightedness or near-sightedness — is a very common eye condition in which you can see nearby objects clearly but distant objects appear blurred. A person with myopia can read a book easily but struggles to read a classroom blackboard or road signs.

What Happens Inside a Myopic Eye?

In a normal eye, light entering through the cornea and lens focuses exactly on the retina — the light-sensitive layer at the back of the eye — producing a clear, sharp image.

In a myopic eye, the eyeball has grown slightly too long (longer than it should be front to back). Because of this extra length, light focuses in front of the retina rather than on it, making distant images blurry.

What Is Axial Length?

The distance from the front of the eye (cornea) to the back (retina) is called the axial length. A normal adult eye is about 23-24 mm long. In myopia, this measurement is longer — sometimes reaching 26, 28 or even 30 mm in severe cases.

How Is Myopia Measured?

Myopia is measured in dioptres (D) with a minus (-) sign. A higher minus number means stronger short-sightedness.

What Are the Symptoms?

• Difficulty seeing a blackboard, TV screen, or road signs clearly
• Squinting to see things at a distance
• Needing to sit at the front of a classroom
• Headaches after looking at distant objects for a long time
• Holding a phone or book very close to read

Can Myopia Be Corrected?

Glasses and contact lenses correct the blur immediately by compensating for the extra eye length. However, correction only fixes the blurry vision — it does not stop the eye from continuing to grow longer. That is why myopia control (slowing progression) is as important as correction.