digital eye strain

DIGITAL EYE STRAIN / COMPUTER VISION SYNDROME

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The explosion of communications technology and the ongoing introduction of new portable electronic devices in recent years have given us many ways to access information and interact with each other more easily and more efficiently than ever before.  However, there is a cost associated with all that surfing, reading, texting, e-mailing, blogging, chatting, tweeting and game playing we do these days on our e-notebooks, tablets and smart phones — it's called digital eye strain.  Virtually everyone who uses a computer or portable electronic devices for extended periods of time is at risk of digital eye strain.

Define

Digital eye strain is now the most common computer-related repetitive strain injury among workers, surpassing carpal tunnel syndrome and tendonitis.  The long hours people spend on their computers and portable electronic devices these days along with the nature of the digital screens themselves contribute to increased potential for eye strain, compared with reading the same information printed on paper.  This is because characters on computer screens are made up of tiny dots of light called pixels (literally, "picture elements"), and lack the uniform density and sharply defined borders of text characters printed with ink on paper.  Even on high-definition displays, text characters formed with pixels can be less distinct than those formed on a printed page. This is especially true if you tend to hold your smart phone or other device closer to your eyes than the recommended viewing distance.  Even the best-quality images formed on computer screens are more difficult for the eye to stay focused on, compared with print on paper. Constant refocusing causes fatigue of the focusing muscle inside the eye, which is a major component of digital eye strain.

Risk Factors

The total amount of time you spend staring at a screen on a daily basis.

How close you sit to your computer screen and how close you hold devices to your eyes.

The types of activities for which devices are used. (Action games may cause eye fatigue quicker than surfing the Web, texting or reading an e-book.)

How often you blink.

How long you stay in front of your screen(s) each session and how many breaks you take.

Whether you have dry eyes or uncorrected vision problems (astigmatism, for example).

Signs and Symptoms

Red, irritated eyes

Dry eyes

Intermittent blurred vision when viewing your screen or device

Blurred distance vision when looking away from your screen or device

Headaches

Neck and/or back pain

These Signs and Symptoms May be Caused by One or More of the Following:

Poor lighting

Glare on the computer screen

Improper viewing distances

Poor seating posture

Uncorrected vision problems

Prevention or reduction of digital eye strain involves taking steps to control lighting, glare on the computer screen, establishing proper working distances and posture for computer viewing, and assuring that even minor vision problems are properly corrected.

How is Digital Eye Strain Diagnosed?

Digital eye strain can be diagnosed through a comprehensive eye examination. Testing, with special emphasis on visual requirements at the computer working distance, may include:

A thorough patient history.

Visual acuity measurements.

A detailed refraction to determine the appropriate lens power needed to compensate for any refractive errors (nearsightedness, farsightedness or astigmatism).

Binocular vision testing, enabling the analysis of how the eyes focus, move and work together.

Using the information obtained during your examination, your optometrist can determine if you have digital eye strain and advise you on appropriate treatment options.

How is Digital Eye Strain Treated?

Eye and Vision Care

Computer Lenses

Lenses may be prescribed to meet the unique visual demands of computer viewing may be required.  Eyeglasses or contact lenses prescribed for general use may not be adequate for computer work.  Even people who do not require glasses or contact lenses for general use may require specific lenses prescribed for daily, long term computer use.  Special lens designs, lens powers, tints or coatings may help maximize visual abilities and comfort.  

Visual Eye Exercises

Visual eye exercises, also known as Vision Therapy or Orthoptic Training, is equated to physical therapy for the eyes.  There are some eye focusing or eye coordination disorders that can't be adequately corrected with eyeglasses or contact lenses. Vision therapy is a structured program of visual activities prescribed to improve visual abilities, helping to remediate deficiencies in eye movement, eye focusing and eye teaming.

Treatment of Dry Eye

Addressing the underlying condition of dryness could dramatically improve the comfort of your eyes.  Blinking is a necessary function of our eyes, spreading our tears smoothly across the front surface of our eyes, to keep our eyes moist and our vision clear.  Our blink rate dramatically declines when we are focused on a task.  Dryness is more likely to worsen under these conditions.  It is important to address the underlying condition of dryness to optimize eye health and visual comfort.  

Viewing the Computer

Rest Breaks Following the 20/20/20 Rule

Every 20 minutes, look away from your screen and focus on an object 20 feet away for 20 seconds. This simple technique reduces eye fatigue by relaxing the focusing muscles as well as reducing dryness by stimulating the blink reflex.

Blinking

Reduce your risk of developing dry eye by making a conscious effort to blink frequently. Our blink rate tends to decline when we focus on certain tasks such as computer use and blinking will keep the front surface of the eye moist.  

The Computer Screen

Location

Optimally, the computer screen should be 15 to 20 degrees below eye level (about 4 or 5 inches) as measured from the center of the screen and 20 to 28 inches from the eyes.

Resolution

It is best to use a high resolution screen.

Increase the font size on your screen.

Reference Materials

The goal is to position the documents so you do not need to move your head to look from the document to the screen.  Ideally, these materials should be located above the keyboard and below the monitor if possible.

Seating Position

Chairs should be comfortably padded and conform to the body. Chair height should be adjusted so your feet rest flat on the floor. Your wrists shouldn't rest on the keyboard when typing.

Lighting and Glare

Minimize the amount of glare induced by lighting by maximizing the use of soft lighting tones and minimizing cooler tones, such as fluorescent lighting.

Regular eye examinations and proper viewing habits can help to prevent or reduce the development of the symptoms associated with Digital Eye Strain.