Refractive Errors

Refractive errors — myopia (short sight), hypermetropia (long sight), astigmatism, and presbyopia after 40 — are the most common vision problem in the world. Uncorrected refractive error is a major driver of poor school performance, road accidents, and falls in older Indians — and it is entirely treatable with glasses.

The four types

• Myopia (short sight) — distance blur. Rapidly rising in Indian urban children.
• Hypermetropia (long sight) — near blur, can cause headaches in children.
• Astigmatism — blur at all distances from an irregular cornea.
• Presbyopia — age-related near-vision loss starting around 40; universal.

The urban Indian myopia epidemic

• Myopia in urban school-age Indian children has roughly doubled in the last 25 years; higher in screen-heavy, indoor lifestyles.
• High myopia later increases the risk of retinal detachment and glaucoma — so slowing its progression matters.
• Two hours of outdoor activity a day in daylight is protective.
• Specialised low-dose eye drops, special glasses, and orthokeratology are options to slow progression in children — an eye doctor decides.
• Regular school vision screening (many Indian states run this free) picks up children early.

Treatments

• Glasses — cheapest, safest, flexible. Buy from a qualified optometrist/ophthalmologist; avoid roadside "chashma" that skips proper refraction.
• Contact lenses — good alternative but with strict hygiene; corneal infections from poor contact-lens care are serious.
• Laser surgery — LASIK, PRK, SMILE — for stable prescription, over 18, no active eye disease. Widely available in Indian cities. Not suitable for everyone — thin cornea, keratoconus, severe dry eye are contraindications.
• Lens-based surgery (ICL) — for very high myopia or thin corneas.
• Reading glasses / progressive lenses for presbyopia.

When children need a check

• Squinting, moving closer to the screen/board, headaches, rubbing eyes, tilting the head.
• Copying from the blackboard is difficult.
• One eye turning in or out — possible squint (see Squint page).
• Family history of high myopia.