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| WHAT IS IT? |
Presbyopia is the progressive inability of the eye to focus
clearly on near objects. What exactly causes this is unknown,
but it happens to everyone as a natural part of aging. In
order for us to see images clearly, light rays that allow
us to see objects enter the eye, where the lens bends and
focuses the rays on the retina. The lens changes shape to
accommodate the differences in light coming from objects at
different distances. The human lens gradually stiffens and
loses the ability to change shape. By the time we are in our
40s, the stiffness has progressed to the point that light
rays from close objects cannot be properly focused, and we
begin to experience blurred vision when we try to do tasks
that require up-close focus, such as reading or needlework.
The lens continues to stiffen until about age 60, when nearly
all elasticity has been lost. Presbyopia eventually affects
everyone, even people who are already farsighted (hyperopic)
or nearsighted (myopic). Because people who are farsighted
already have difficulty focusing on near objects, they may
experience presbyopia a little earlier in life. People who
are nearsighted may find that their near vision is better
when they read without their glasses. |
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| SYMPTOMS |
Presbyopia causes the following symptoms:
1. Difficulty reading at a previously comfortable
distance (words appear blurred)
2. Needing to hold reading material or other close
objects further away from your eyes to
gain clarity
3. Needing brighter light to see clearly (bright
light constricts the pupils, which increase the
depth of focus)
4. Difficulty reading late at night, or when you
are tired or stressed
5. Eye discomfort, fatigue or drowsiness when
doing close work because of the strain of eye
6. muscles working to change the lens shape.
7. Headaches |
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| DIAGNOSIS |
Many people over age 40 self-diagnose presbyopia based on
their inability to read clearly at a distance that used to
be natural and comfortable. Because the condition comes on
gradually over many years, most people don't notice small
vision changes and delay seeking professional help until the
focusing problems interfere with daily life. We will test
your vision by having you read text at a distance that is
typically comfortable to you. If we diagnose presbyopia, we
will determine the extent of the focusing problem. The appropriate
lens prescription is made by progressively increasing the
magnification power of corrective lenses until the words on
the page are clear to you and you are comfortable reading.
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| EXPECTED DURATION |
Presbyopia is irreversible and gets worse as we get older,
starting around 40 years of age and plateauing at about age
60. |
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| PREVENTION |
Nothing can be done to prevent presbyopia. It is an inevitable
part of aging. However, people who do a lot of close visual
work (such as working with a computer or intensive reading)
may develop presbyopia prematurely. If you do close work,
take a 5-minute break every half an hour to relieve strain
on the eyes. Allow your eyes to focus on objects at a middle
or long distance to give your eyes a rest from close focusing.
Be sure to use bright lighting when reading to help your eyes
focus. |
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| TREATMENT |
Presbyopia is completely treatable with corrective lenses.
Glasses are the simplest way to regain near-vision clarity.
If you already wear corrective lenses for nearsightedness
or farsightedness you may need two sets of prescriptions --
one for distance vision and one for near vision. Glasses may
have bifocal lenses, in which the upper portion of the glass
is corrective for distance and the lower portion for near
vision. The optometrist will order the appropriate prescriptions.
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If
you don't already wear corrective lenses or you wear contact
lenses, you may opt to wear simple reading glasses only when
necessary to magnify near objects. |
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Standard,
off-the-rack reading glasses may not be right for everyone.
Many people need different amounts of correction in each eye,
and therefore require custom glasses. Also, custom glasses
are usually made of better materials and are shaped to allow
your eyes to focus properly across the full range of the lens.
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Note:
Because presbyopia continues to get worse as we age, the right
magnification this year may not be sufficient next year. Continue
to seek out reading clarity; it's not a sign of weakness to
have to increase the strength of your glasses. |
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Contact
lenses can also be used to treat presbyopia, although many
people find it difficult to adjust to them. Bifocal contact
lenses can be made, or you may opt for monovision lenses,
in which one eye has a contact lens with a prescription for
distance vision, and the other eye has a contact lens for
near vision. We will help determine the best course for you.
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| WHEN TO CALL US? |
Although there is no harm in delaying treatment for presbyopia,
we recommend an examination whenever you have blurred vision
in order to rule out other possible vision problems or health
complications and to identify other possible coexisting disorders.
For example, cataracts may also cause blurred vision. Diabetes,
vascular disease and other systemic diseases can affect vision
too. If your vision suddenly blurs, or if you have eye pain
or double vision, see black spots or light flashes or have
other visual problems, call us immediately. |
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| PROGNOSIS |
After you get over the initial emotional shock of discovering
you need reading glasses, you'll be fine. With proper corrective
glasses or contact lenses, you will be able to read and do
other close work as well as ever. |
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