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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