What are the most common vision problems?
The eye functions very much like a camera. The front part
of the eye--the cornea and lens--focus light onto the back
of the eye, or retina. This is very similar to how the lens
of a camera focuses light onto the film inside the camera.
Once the retina receives an image, it transmits a signal to
the brain, via the optic nerve, for the image to be
developed. The most common vision problems are refractive
problems. This means that the shape of your eye does not
bend, or refract, the light coming into the eye properly so
the image sent to the brain looks blurry.
The most common problems include:
- nearsightedness (myopia)
- farsightedness (hyperopia)
- the loss of close reading vision (presbyopia)
- astigmatism, or distorted vision.
What is nearsightedness?
Nearsightedness is a vision condition that allows clear
viewing of close objects, but distant objects are out of
focus. It occurs when the eyeball is too long or when the
outer layer of the eye, called the cornea, has too much
curvature. This causes light rays to focus at a point in
front of the retina instead of directly on it. A sign of
nearsightedness may be squinting to see road signs clearly.
A nearsighted child may not be able to read the chalkboard
at school or to watch TV without sitting very close.
Nearsightedness may be helped with glasses, contacts, or
LASIK surgery.
What is farsightedness?
Farsightedness is a vision condition that allows clear
viewing of distant objects, but close objects are out of
focus. It occurs if the eyeball is too short or the cornea
has too little curvature. This causes light rays to focus
behind the retina instead of directly on it. Some signs of
farsightedness include blurry vision when looking at objects
up close. You may also notice eyestrain, fatigue, aching or
burning eyes, and headaches after doing close work (such as
reading or needlework). Often babies are born with a slight
farsightedness that clears up as they grow and their
eyeballs become longer. Children with farsightedness may
not be interested in reading or they may have trouble
concentrating because they cannot keep close objects in
focus. Farsightedness may be helped with glasses, contacts,
or LASIK surgery.
What is presbyopia?
Presbyopia is similar to farsightedness. It is a condition
that occurs as a natural part of the aging process. You
usually start noticing this change in your early to
mid-forties. A loss of elasticity of the lens of the eye
results in an inability to bring close objects into focus.
Some signs of presbyopia include blurred vision at normal
reading distance and the tendency to hold things at arm's
length to read them, as well as eye fatigue and headaches
when doing close work. Contacts are sometimes used for
presbyopia. However, it is often easier for people who
already wear contacts to get reading glasses that magnify
close-up objects.
What is astigmatism?
Astigmatism is vision that is distorted or blurred. With
this vision problem, the normally round cornea is not round.
This prevents light from focusing properly on the retina.
Astigmatism causes far and near vision to be distorted and
blurry. Astigmatism is usually present at birth. Mild
astigmatism may cause headaches, eyestrain, fatigue, or
blurred vision but may not require glasses or contacts.
Severe astigmatism requires correction with glasses or
contacts. Astigmatism may also be treated with LASIK
surgery.
When should I see my eye care provider?
See your eye care provider if you are concerned about your
vision. The American Academy of Ophthalmology recommends
that you have a complete eye exam according to the following
schedule:
- Ages 20 to 29: at least once during this time
- Ages 30 to 39: at least twice during this time
- Ages 40 to 64: every 2 to 4 years
- Age 65 or older: every 1 to 2 years.
If you have a family history of certain diseases such as
glaucoma or if you have medical problems such as diabetes,
more frequent visits may be recommended, even if you are not
having any eye symptoms.
This content is reviewed periodically and is subject to
change as new health information becomes available. The
information is intended to inform and educate and is not a
replacement for medical evaluation, advice, diagnosis or
treatment by a healthcare professional.
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