Page 39 - The Book Pi in eye

Pi in eye

Also, you will need to bring your glasses and/or contact lenses.
You may need to bring sunglasses, in case the doctor will instill eye
drops to dilate your pupils. Enlarged pupils will make you very light
sensitive as well as causing blurry vision for a few hours.

Eye Examination Day:

During the examination, the doctor may look at different factors.
The appointment may last over one hour. The doctor may use
different forms of tests to make sure that your eyes are healthy, and in
good condition. You may wonder, “What does the doctor look at?”
The doctor checks for any of the following conditions:
 Myopia (nearsightedness)
 Hyperopia (farsightedness)
 Presbyopia
 Glaucoma
 Cataracts, dryness, etc.

Determining the Health of Your Eyes:

The doctor can use the Visual Acuity Test, which helps understand
the clarity of your vision. You may have heard of people saying that
they have 20/20 vision and this is what the test determines. The
doctor will use the familiar Snellen chart, which contains a series of
black letters that vary from big to small font, put onto a white screen.
The results from the visual acuity test are expressed as 20/20 or
20/40. The first number expresses the fixed distance of twenty feet at
which the test is conducted. The second number is the distance a
person with perfect vision can see the same letter from. For example,
if your visual acuity is at 20/40, then whatever you are seeing at
twenty feet a person with perfect vision can see at forty feet. If your
vision is 20/80 your vision is one-fourth as good as normal. At
20/200 a person is considered legally blind.

Axial length:
 Laser biometry- IOL Master or Lenstar measures the
distance from the corneal vertex to the retinal pigment
epithelium employing a light beam. This allows for
accurate measurements of eye length. Both the instruments

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