Vision & Refraction

VISION AND REFRACTION FOR ADULTS AND KIDS

What is Refraction?        

         
Refraction is an Eye exam that measures a person's Prescription For Eye Glasses or Contact Lenses.

How It is Done??          

          
The Ophthalmologist or Optometrist Ask you to sit in a chair and to focus on an eye chart 20 feet (6 m) away. The test is performed by one eye at a time. The ophthalmologist or Optometrist will ask if the Chart appears more or less clear with the trial lenses of Different Strength.

Why the test is Performed? 

The test is performed as a part of Routine eye exam to determine whether you have a refractive error (for the need of glasses or Contact lenses).

Types of Refractive Errors

-    Myopia (Nearsightedness) 
-    Hyperopia (Farsightedness) 
-    Astigmatism (Abnormally Curved Cornea)       
-    Presbyopia (Inability to focus Near Object that develop with Age)

What are refractive errors in children?

Refractive, or optical, errors – myopia, hyperopia and astigmatism – cause blurred vision due to an inability to focus images on the retina. If not corrected, their consequences can be particularly harmful for children, since vision is developed in the first years of life.

Any cause of poor vision in one or both eyes during childhood, as is the case with refractive errors, can lead to the condition known as "lazy eye". When the child has hyperopia, astigmatism or myopia, the image that reaches the brain is not sharp.

Visual Screening Tests for a Baby

Here are some of the ways your baby's vision can be tested: 

1.    Response to light. A baby will blink in response to a bright light.

2.    Pupil response. Measuring the response of the black center part of the eye (the pupil) by shining a light in the eye.

3.    Ability to follow a target. The most common vision acuity test in babies is a test to check the ability to look at and follow an object or toy.

4.    Visually evoked potential/response testing. These are tests that stimulate the eyes with either a bright light or special pattern. The baby is connected to a special monitor with attachments on the baby's head. The machine then records electrical activity in the brain as the lights and patterns are shown to the baby.

Visual Screening Test for an Older Baby and Toddler

Many of the above tests may be done, as well as the following:

Cover and uncover test. This test checks the alignment of the eyes when a child is focusing on an object. One eye is covered with an opaque card while the child stares straight ahead. The examiner then observes the uncovered eye for movement.

Visual Screening Tests for a Preschooler

Around age 3, some of the same tests that are used for a toddler may be done, as well as the following:

1.    Visual acuity tests. Specific tests and charts may be used to measure both near and distant vision. In a preschooler, these charts may show pictures or stories instead of letters of the alphabet.

2.    Color testing. This test helps find color blindness in a child.

Visual Screening Tests for a School-Aged Child
In this age group, formal vision tests can be completed with special charts or devices that aid with testing vision. Both near and far vision can be evaluated.

What are the symptoms of refractive errors?

Double vision.

Hazy vision.

Seeing a glare or halo around bright lights.

Squinting.

Headaches.

Eye strain (when your eyes feel tired or sore)
Trouble focusing when reading or looking at a computer.

Treatment:

The most common treatment for refractive disorders are eyeglasses, contact lenses, or surgery. Eyeglasses are the most simple and safest way to correct refractive error issues.