Refractive Errors


Refractive Errors

A refractive error is a common eye problem which occurs when the eye cannot clearly focus the images from the outside world. The result of refractive errors is severe blurred vision.


Myopia (Nearsightedness; Minus Power)

Nearsightedness, or myopia is a condition where near objects are seen clearly, but distant objects are not clear. This occurs due to light rays focus in front of the retina due a longer eye ball. Nearsightedness is a common vision condition affecting nearly 20% of the Indian population. Mostly starts in school-age children and as the eye grows during childhood, nearsightedness may increase up to the age of 18 to 21.

Signs & Symptoms

Difficulty seeing distant objects like TV screen and difficulty in seeing blackboard in the school


Hyperopia (Farsightedness: Plus Power)

Hyperopia-FarsightednessFarsightedness or Hyperopia is a condition where distant objects are seen clearly than close ones. This occurs due to light rays focusing behind the retina due a shorter eye ball. Common signs of farsightedness include difficulty in clearly seeing near objects, headaches, eye strain, and/or fatigue after close work.

High Myopia (High Minus)

High myopia usually describes minus power of -6.00 or more. High myopia could be progressive even after 20 years of age and may increase very severely, which is called pathological myopia. People with high myopia are more likely to have retinal problems like retinal Holes and retinal detachment They are also more likely to experience floaters (floating spots, lines or cobwebs which appear in front of vision).

Presbyopia (Plus Power)

Presbyopia is a normal aging phenomenon by the age of 40, where our normal lens of the eye loses its flexibility thus making it difficult to focus on near objects. The signs of Presbyopia include inability to read small prints at normal reading distance, the tendency to hold reading materials away from the eyes, inability to thread the needle, eye fatigue and headache after doing close work.

Astigmatism (Cylindrical Power)

Astigmatism-Cylindrical PowerAstigmatism is a condition where the front surface of your eye, the cornea, is irregular in shape preventing the light to focus at one point on the back of your eye, the retina. As a result, the vision would be blurred at all distances and is often associated with short sight or long sight. Astigmatism can be corrected with eyeglasses and/or contact lenses. However, higher astigmatism may be better handle by surgical means like astigmatic keratotomy or LASIK.

What are the Treatment options for Refractive errors?

  • Glasses:

The most common temporary solution to correct refractive errors due to easy maintenance and low cost. The drawbacks of spectacles are obvious-they interfere with activities and change a person’s appearance. But glasses sometimes decrease peripheral vision.y from the eyes, inability to thread the needle, eye fatigue and headache after doing close work.

  • Contact lenses

contact-lensContact lenses are alternatives to spectacles. They provide excellent peripheral vision unlike glasses. Contact lenses are cosmetically better. Problems with contact lenses include their recurrent costs and maintenance.

Permanent options

There are various surgical options available for the permanent correction of these refractive errors.

Eligibility for Refractive Surgery

  • Should be above 18 ??? 21 years and should have a stable spectacle power for over a year.
  • Should not have any other eye disorders like cataract, glaucoma, retinal disorders etc.

Lasik (Laser in Situ Keratomileusis)

In Lasik, the corneal surface is reshaped using a laser beam. It corrects vision by altering refractive power of the eye by a calculated change in the corneal curvature.

Wavefront Lasik or Customized Lasik

In Wavefront guided Lasik, Optical aberrations (imperfections) inherent in the eye is also corrected Conventional Lasik can only correct the spectacle power & not these subtle optical aberrations. With Wavefront guided Lasik, it is now possible to reduce these aberrations and enhance vision much above the normal levels. This is also referred as Custom Lasik / Zyoptix or Opti Lasik