By William Benevento, MD, Eye Surgeons Associates
Many
people wonder what is involved in a “routine” eye exam, the type of exam
you get once every year or two. Most think that if their vision is OK,
they do not need to see their eye doctor. Unfortunately, many ocular
diseases in their early stages do not give an obvious warning sign. In
fact, two of the most common causes of blindness, diabetes and glaucoma,
rarely start off with decreased vision. The two goals of the routine
exam are to discover any eye problems that need treatment now and to
prevent any potential damage to the eye in the future through early
detection.
The first step in any eye exam, routine or otherwise, is
to talk with you and find out if you have any symptoms of eye disease.
We also find out if you have any diseases that could affect the eyes,
such as diabetes or high blood pressure. Your current medications are
written down (some of them can contribute to cataracts, dry eyes, and
glaucoma), and as some eye diseases are hereditary, we also ask you if
your relatives have any eye problems.
The first eye test is to check
your vision. You should be able to read the 20/20 or 20/25 line on the
chart with your glasses on (if you need any). Anyone with vision less
than this needs to be checked for new glasses. Reading vision is also
measured as some problems, such as cataracts, can affect distance vision
more than reading vision. Side vision is checked for any losses that
would suggest a stroke or glaucoma. An Amsler Grid, which looks just
like graph paper, tests central vision for any waviness or spots. These
could indicate problems such as diabetes or macular degeneration in the
retina, the light sensitive layer coating the inside of the eye. Eye
movements are checked for any weakness or crossing, and the pupils are
looked at with a bright light. If the pupils react unequally to the
light, it could suggest problems with the nerves that bring the
information from the eyes to the brain. Next, eye pressure is tested as a
screening for glaucoma. Finally, the eyes are dilated for the second
half of the exam. All this frequently happens before you even see the
eye doctor.
The first thing that the doctor does is to take a look at
your chart and ask you about any problems that you have been having
with your eyes. We recheck anything suspicious in your examination up to
this point. The next test is the slit lamp exam. The slit lamp is a
table-mounted microscope that gives us a magnified view of the eye. With
it, we can look at the front half of the eye for any problems including
infection, inflammation, dryness, or cataracts. The cause of most eye
irritation or pain is diagnosed at the slit lamp.
The final part of
the evaluation is the dilated examination. Dilating drops enlarge the
pupil, giving us a much better view into the back half of the eye.
Though dilation also makes you somewhat light sensitive and blurs your
reading vision for a few hours (distance vision usually does not change
much), it still is a very important part of the exam and should not be
skipped. The dilated eye is one of the few places in the body where we
can see the blood vessels. Because of this, we can frequently pick out
patients with poorly controlled high blood pressure, diabetes, or a high
risk for strokes. A good view of the nerve as it enters the eye lets us
diagnose early glaucoma, high pressure around the brain, and
inflammations of the nerve such as multiple sclerosis. A careful
evaluation of the retina reveals evidence of macular degeneration,
HIV/AIDS, or rips which can lead to detachments.
No examination is
complete without a thorough explanation of any findings. If your vision
is not 20/20 or 20/25, you should know why and what, if anything, can be
done about it. You should have a general understanding of the health of
your eyes before you leave the office; ask questions if you do not. Our
sight is the most important of our senses; we owe it to ourselves to
get it checked regularly.
Dr. Benevento is a board-certified
ophthalmologist. He has special interest in diabetes and the surgical
treatment of cataracts with the latest techniques. Dr. Benevento
practices at Eye Surgeons Associates Bettendorf and Muscatine, Iowa
offices. For more information, please see our website:
www.esaeyecare.com.