Common Vision Problems
What are the most common vision problems?
The eye works 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. Once the retina receives a picture, it sends a signal to the brain, via the optic nerve, for the picture to be developed. The most common vision problems are those where the shape of your eye does not bend the light coming into the eye properly. This makes the picture that is sent to the brain look 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 means that you see close objects clearly, but distant objects are out of focus. It happens when the eyeball is too long or when the outer layer of the eye, called the cornea, is too curved. 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 refractive surgery.
What is farsightedness?
Farsightedness is when you see distant objects clearly, but close objects are out of focus. It happens if the eyeball is too short or the cornea is too flat. 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 get 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 refractive surgery.
What is presbyopia?
Presbyopia is similar to farsightedness. It is 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. You may also have eye fatigue and headaches when doing close work. Contacts are sometimes used for presbyopia. However, it may be easier for people who already wear contacts to get reading glasses that magnify close-up objects.
What is astigmatism?
With this vision problem, the normally round cornea is not round. This prevents light from focusing properly on the retina. Astigmatism makes your vision distorted and blurry. Astigmatism is usually present at birth.
Mild astigmatism may cause headaches, eyestrain, fatigue, or blurred vision. Severe astigmatism is corrected with glasses or contacts. Astigmatism may also be treated with refractive surgery.
When should I see my eye care provider?
See your eye care provider if you are concerned about your vision. If you don't have symptoms, the American Academy of Ophthalmology recommends eye exams according to the following schedule:
- Any child who fails a school vision screening test
- 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
You may need to see your eye care provider more often if you have certain eye problems, diseases, or risk factors. For example, if glaucoma or diabetes run in your family. Have your eyes checked regularly even if you do not have eye symptoms.
Reviewed for medical accuracy by faculty at the Wilmer Eye Institute at Johns Hopkins. Web site: http://www.hopkinsmedicine.org/wilmer/
Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.
HIA File opth4203.htm Release 13/2010