Asthenopia

Are your eyes tired, sore or achy? Do you notice these symptoms after reading for prolonged periods of time? Perhaps your eyes feel fatigued after responding to a series of text messages on your smartphone. You may be experiencing asthenopia or excessive eye strain.

Symptoms

Asthenopia may include the following symptoms:

• Headache
• Nausea
• Fatigue
• Sleepiness

• Light sensitivity
• Blurred vision
• Eye strain
• Eye soreness
• Eye pain
• Burning eyes
• Dry eyes
• Difficulty reading
• Irritability
• Poor concentration

Causes

Asthenopia seems to occur after lengthy periods of intense focusing, such as reading or driving. The condition is caused by a shortage of brain activity that is required for proper focusing and eye-muscle coordination. In some people, asthenopia is caused by various binocular vision disorders. Binocular vision disorders are vision problems that occur when both of our eyes do not fuse an image together properly and without symptoms. Because have two eyes, we are able to properly view the world and locate objects in three dimensions (depth perception.) When an imbalance occurs between the eyes, usually due to an optical problem or an eye muscle problem, binocular vision disorders occur.

Research has shown that frequent use of smartphones and other handheld electronic devices may lead to asthenopia symptoms.

Surfing the Internet or reading text messages or emails on a smartphone can be extremely taxing to the visual system, as the eyes must strain to read the often tiny fonts.

Risk Factors

Having a binocular vision disorder puts you at greater risk for asthenopia. However, people who work on the computer for a good portion of the day are also at a higher risk of developing symptoms.

Studies have shown that up to 70% of computer users experience asthenopia at some point.

Computer users are not the only ones at risk. Certain professionals, such as radiologists, lawyers, and accountants who complete daily intensive "near work," sometimes suffer significant eye strain. Older retirees who spend their time surfing the web also have a high risk, especially since this population has a higher incidence of dry eye syndrome.

Treatment

Treatment for asthenopia does exist, but the first step is an accurate diagnosis. Most of us experience asthenopia from time to time. However, some of us may actually have a job where extended computer use is required. We may experience excessive eye strain to such a degree that it can be debilitating.

Not all eye doctors treat this problem. So, it is recommended that you find a doctor who treats binocular vision disorders and practices in-office or home visual therapy. Most eye doctors treat basic binocular vision disorders. However, more involved binocular vision disorders (or disorders that require longer treatment plans) are treated by eye doctors who specialize in vision therapy. Most doctors that specialize in vision therapy are optometrists.

They may call themselves a behavioral optometrist or may just state they prescribe vision therapy. Patients should call and ask to make sure. If certain eye muscle problems cannot be corrected with vision therapy, then sometimes an ophthalmologist that specializes in eye muscle surgery should be consulted. For a correct diagnosis, your eye doctor will attempt to stress your visual system during a comprehensive eye examination in an attempt to produce symptoms. Although a simple eyeglass prescription may be a part of the treatment plan, certain eye or lens exercises may help your symptoms.

Prevention

If you think you have the condition, the following tips may help alleviate symptoms:

• Every 20 minutes of use, look away from your computer at a far distance or take a break for 20 seconds.
• Increase the font size on computers and handheld devices.
• Use proper lighting for intense near-point tasks.
• Blink often.
• See your optometrist or ophthalmologist if symptoms persist. If symptoms are bothering you on a daily basis, then you should not wait. At a minimum, it is recommended that you have a comprehensive eye exam with your primary eye doctor first to be evaluated.

Statistics

Asthenopia appears to be on the rise. The following statistics help illustrate the many ways your eyes may be stressed by your lifestyle:

• Approximately 80% of Americans have access to the Internet.
• Over the last 10 years, Internet access and usage have grown by 444%.
• Over 1 billion texts and 347 billion e-mails are sent daily.
• Americans use their cell phones an average of 21 minutes per day.
• Thirty-five percent of 8-year-olds in the United States have a cell phone.
• In 2012, the number of households worldwide with next-generation game consoles will be estimated to be 190 million, 80% of which will be connected to the Internet.
• The use of various electronic media increases the demand on our visual systems. In particular, 3D viewing can overload a person who already has asthenopia or other focusing issues. He or she may actually become physically ill while trying to watch one of the new 3D video devices.
• Miniaturized screens with reduced video and text are also increasing our visual demand.