Computer Vision Syndrome

We spend the greater part of our life before computer screens unaware that it causes a condition known as Computer Vision Syndrome (CVS).CVS is characterized by eye strain associated with prolonged computer use.

The eye needs lubrication to function smoothly. The rate of blinking is reduced when a person spends long hours in front of a computer. This affects the tear film and therefore leads to the occurrence of Computer Vision Syndrome.

Millions of computer users across the world experience an eye problem sometime or the other in their career. Spending long hours each day in front of a computer leads to symptoms of Computer Vision Syndrome. With more and more adults and children using computers on a daily basis CVS has now become a common vision complication encountered in eye clinics.

Among the symptoms of CVS are tired eyes, eye strain, periodic blurred near vision, occasional blurred distance vision, headaches, dry eyes, burning eyes, red eyes and glare sensitivity.

Why CVS?

The normal blink rate in human eyes is 16-20 per minute. Blink rate tends to decrease to a low of 6-8 blinks per minute when there is persistent viewing of the computer screen. This over a period of time can lead to dry eyes. Symptoms of Dry Eyes are usually seen among people in the age group of 30 - 40 years and above.

People who are already nearsighted, farsighted, or have astigmatism are more likely to develop CVS. Symptoms of CVS can be broadly classified as "asthenopia". The near focusing for long hours puts undue strain on ciliary muscles of the eye. This is the cause of eye fatigue or tiredness and also leads to disruption in the accommodative process of the eye.

Computer users often assume awkward postures as a compensatory mechanism to position their eyes while working - resulting in musculoskeletal symptoms like neck and back aches.

Simply put CVS can basically result due to poor workplace design and practices or by not paying attention to the small tips that go a long way in maintaining good eye care.

More than 2 hours per day of computer use predisposes to computer vision syndrome.

People who suffer from CVS may experience the following symptoms:-

• Eyestrain (non-specific ocular discomfort)
• Blurred distant vision
• Fatigue
• Dry or irritated eyes
• Headache
• Blurred near vision
• Diplopia (double vision)
• Neck or backaches

Management of Computer Vision Syndrome Ergonomics

• Adjust the position of your computer screen. A viewing distance of 20" to 26" inches is ideal.
• The monitor should be positioned below the level of your eyes
• Viewing Angle should be present. It would be equivalent to about a 10" drop from the straight-ahead gaze line directly above the screen to the center of the screen. This is because the ideal gaze angle is below the horizontal level of the eye.
• Avoid bright overhead lighting that directly falls on your face.
• Use Blinds or curtains to reduce reflection on your screen. Ratio of surrounding light to monitor light should be 3:1
• Use desk lamp to illuminate documents to the same brightness as your screen.
• Use document holder to refer to any reference material

Eye Care Measures

• Remind yourself to blink more often while working at the computer screen. This helps prevent dryness of the eyes.
• Take 15 or 20 second rest breaks every 15 minutes. Use this time to just look around the room.
• Blink, breathe and break. Blink more often, take frequent deep breaths, and take a short break every hour
• Reduce screen glare by adjusting light levels
• Increase font size on your computer screen
• Black characters on a white background are usually the best. Avoid dark or unduly bright backgrounds. The size of the text should be three times the size of the smallest text you can read. The font should enable comfortable reading.
• Keep your computer screen free of dust.
  If having corrective vision anti-reflection coating of spectacles could help. The advantage provided by anti-reflection coating is that it eliminates light reflection and computer glare to a large extent and thereby reduces eye fatigue.
• Have an eye examination before starting to use computer and once a year.
• Above all consult an eye care specialist in case you have any symptoms.