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What should a comprehensive eye exam consist of?

Visiting the Opticians
The optical assistant makes sure that your confidential customer record is accurate and up-to-date.
If your teen is wearing contact lenses, they will need to be removed before the eye test.
Using a non-contact tonometer
Using a non-contact tonometer, the optometrist will blow a few puffs of air into each eye. The air will then bounce back at the instrument, giving a measurement of the pressure inside each eye.This is an important test, as high pressure can indicate the early stages of glaucoma, a sight-threatening condition.
The autorefractor
The autorefractor takes an electronic measurement of how well the eyes focus and gives a read out of your teen’s approximate prescription for the optometrist to use.
If we there is no record of your child’s current prescription, the focimeter can read it from their glasses so that it can be compared with the findings of the eye examination by the optometrist.
About your teen’s health and lifestyle
The optometrist asks questions about your child’s health, his family's health and lifestyle.
It is very important to have a clear understanding of your teen’s vision needs, especially if a particular problem has spurred the visit.
The retinoscope               
The optometrist may use an instrument called a retinoscope which uses different lenses to focus a reflected light beam until it is steady, giving a close guide to the prescription needed.
The retinoscope is very accurate - it is used to test the sight of very small children, or people with communication difficulties who can't easily describe how clearly they can see.
The test chart
The optometrist fine-tunes his findings by asking your teenager to read the test chart through different strength lenses. The results for one eye often vary from those for the other, so each eye will be tested individually before both eyes are finally tested together.
The optometrist flips different lenses in front of the eyes that change how clearly your teen can see. Depending on your teen’s answers, the optometrist changes the lenses until your teen has the clearest, most comfortable vision possible.
Using the ophthalmoscope
The optometrist uses an ophthalmoscope to examine the retina at the back of the eye, including the blood vessels and the front of the optic nerve. This important test can detect changes which can indicate diseases such as diabetes or high blood pressure.
The optometrist darkens the room and then shines a bright light into each eye.
The oxo box
Your teen will be asked to focus on an oxo box, and say whether the illuminated lines are in line horizontally and vertically.
This indicates whether the eyes work well together - balanced and co-ordinated eyes are essential for clear comfortable vision.
The slit lamp
The slit lamp is a powerful, illuminated microscope that is used to examine the outer surface of the eyes, the cornea, the iris and the lens to check for abnormalities or scratches. This is a very important test for contact lens wearers.
Visual field screener
A visual field screener randomly flashes dots of light on a black background. If your teen fails to see any of the dots, this can be an indication of a blind spot.
Testing focus
The optometrist may test your child’s ability to focus at varying distances to decide if he needs different prescriptions for distance and reading.
Discussing your child’s needs
The optometrist will answer any queries you or your child might have during the eye examination, and will explain his findings. If he considers that your child needs new glasses or a change of prescription, he will explain why and recommend the best options.

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