INTRODUCTION:

It is the era of science and technology. Computers are valuable gifts of science to human beings. The use of computers has revitalized almost every sphere of life. Computers have a wide range application in the field of telecommunication, banking, stocking, record maintenance, security analysis, office sheet maintenance, day planning, entertainment, literature, shopping, traveling, ticketing, billing etc. All the surrounding things like ATM machines, petrol pumps, cell phones, tablets, watches, portable play stations and all other modern devices use computer controlling units to conduct their featured operations. Thus, it is impossible to imagine the human life without computers.¹

The workplace is an area where the people spend a major portion of their day. Computers are the important workplace tool. Computers are preferred at workplace as they have increased the productivity and efficiency of work done with the significant reduction in number of workforce. Thus, computers are becoming an important part of the man’s occupational environment day by day. The increasing demand of computers has brought many health challenges among the people using computers in their occupational environment.

Majority of the people engaged in computer related jobs has complaints of visual problems, muscular strain and stress that increase with the amount of computer use.The visual problems are characterized by a number of ocular symptoms such as eye fatigue, dryness, redness, watering eyes, irritation, blurred vision and muscular pain etc. These problems are collectively known as Computer Vision Syndrome (CVS). If not diagnosed and treated at an early stage it may result in loss of productivity among computer users.

Definition

American Optometric Association defines computer vision syndrome as “the complex of eye and vision problems experienced during or related to computer use.”²

Prevalence

It is estimated that presently there are about 12 million computer users in the country.³Computer vision syndrome affects some 50-90% of the people who spend three hours or more a day at a computer (National Institute of Occupational Safety and Health).⁴

Risk factors

The risk factors that may contribute to CVS are -

1. Duration of computer use- A highly demanding, repetitive and extended visual work at computers causes damage to the eye. Several studies have shown that people who spend more than 2-3 hours a day on computer work develops CVS. Lack of rest or alternate task breaks may aggravate the problem.^2,5

2. Low Contrast -The computer screen is made of tiny dots called pixels. These pixels are bright at their center with decreasing brightness towards its outer edge and have different contrasts. So it is difficult for the human eye to focus on it. Letter edge looks fuzzy even when the screen resolution is high which puts additional eye strain.

3. Uncorrected vision conditions- Due to lack of awareness and periodic eye-check-ups, the visual conditions (astigmatism, farsightedness, presbyopia and binocular vision etc.) if not corrected timely, may result in visual discomfort which may further add to CVS.

Fig-1: Effect of Uncorrected vision conditions on eye health

4. Reduced Blinking-Blinking keeps the eyes naturally hydrated and moist that prevents eye dryness. The normal eyes blink 12-24 times a minute. But the prolonged computer use reduces the blinking rates. Thus, it is an important risk factor for CVS.

5. Reduced Eye Movement-Regular eye movements along with blinking helps in spreading the tears all across the eyes that keep the eyes hydrated. Prolonged attention on the computer screen reduces the range of motion of the eyeball resulting in dehydrated eyes and this may lead to CVS.⁵

6. Aging- With advancing age, the eye lenses loses their flexiblility. The eyes lose their ability to focus on near and far objects about the age of 40 years which also called presbyopia. Tear production also decreases with age. Older people generally need more light than younger people for their work. People above 50 years of age needs a twice level of light as compared with that needed for younger people for the same work.

7. Systemic diseases, dysfunctional meibomian glands and medications - Dry eye is associated with some systemic diseases (e.g. rheumatoid arthritis, Sjogren syndrome, other autoimmune diseases). The conditions such as eyelid inflammation (blepharitis) may affect the functioning of meibomian glands. This reduces secretion of an oily substance that prevents eye’s tear film evaporation. The use of diuretics, psychotropics, antihistamines and antihypertensives drugs may also cause dry eyes. These patients are more prone to develop CVS.⁶

8. Lighting Arrangement at the Workplace-An acceptable level of lighting is needed to enhance the visibility of the computer screen. The difference in brightness between the screen and the surrounding area often irritates the eyes. It may be due to an unacceptable level of workplace lighting. The uncovered windows and overhead fluorescent lights emitting bright lights may also result in glare and reflecting images on the screen of the computer.

9. Workplace design and computer adjustment- Ergonomics is the science of fitting the job to the worker. Workplace ergonomics includes adjustable workstation, adjustable chair, foot rests, adjustable monitor, document holder, level of screen, lighting conditions, computer design, protective devices (occupational lenses, special glasses and antiglare screen), brightness and contrast adjustment system, viewing distances and gaze angles for computer work etc. Poor workplace ergonomic may contribute to CVS.²

Occupations at risk of Computer Vision Syndrome

All the occupations involving the computer use for more than 2-3 hours a day may cause CVS. Most common professionals at risk are

clerks, data entry operators, accountants, bankers, database administrators, data analysts, software designers, security engineers, software engineers, web developers, software designers, software analysts, graphic designers, radiologists etc. People handling electronics databases such as writers, scientists, doctors and nurses may also develop CVS.⁷

Sign and Symptoms of CVS

The patients with CVS may be presented with asthenopia, ocular surface, extra-ocular symptoms and visual problems-

1. Symptoms related to Asthenopia or Accommodative mechanism - eye strain, tired eyes, sore eyes, dryness etc.

2. Symptoms related to ocular surface -eye tearing, irritation, itching, redness, burning, contact lens problems etc.

3. Symptoms related to visual problems-blurred vision, difficulty in changing the focus, double vision, presbyopia etc.

4. Symptoms related to extra ocular problems- neck pain, shoulder pain, back pain, headache etc.

Diagnosis

The diagnostic tests for CVS examination and their purposes are-

1. Patient history and eye examination- To obtain a detailed history regarding the presence of general health problems and use of medications that can cause headache and dry eye, duration of computer use or contributing environmental factors, sign and symptoms.

2. Visual acuity measurements- To assess the extent of affected vision (nearsightedness and farsightedness).

3. Refraction test- To identify refractive errors (farsightedness, nearsightedness or astigmatism) and also to determine the appropriate lens power needed for correction.

4. Orthoptic evaluation – To assess ocular muscle coordination and status evaluation.

5. Tear function evaluation- To assess the volume and rate of tear production and also to determine tear gland dysfunction.

6. Others

· Work stress and ergonomics assessment-It includes ergonomics assessment of organizations for computer work.

· Employee vision screening – In this visual system evaluation of workers is done at workplace to evaluate the vision problems.

· Annual CVS check – Incorporation of eye health care in periodic health care guidelines helps in early detection of CVS symptoms among the computer workers e.g. IT industry.⁸

Prevention and Management of CVS-

1. Maintain a good eye health

· Take advice from an ophthalmologist for diagnosis, treatment and management of CVS.

· Visual problems should be corrected by using spectacles or contact lenses.

· Drink plenty of fluids in the form of lemon water, coconut water, fruit juices, milk etc. to prevent dehydration.

· Take the food rich in omega-3 fatty acids, zinc, vitamin-C, vitamin-A and vitamin-E. Consume food rich in these nutrients such green leafy vegetables(e.g. spinach, kale), eggs, nuts, beans, carrots, citrus fruits (e.g. oranges, lemon), tomatoes, fishes like salmon etc.

· Use eye health supplements and artificial tear drops as prescribed by physician.

· Keep yourself up to date regarding CVS through contact with health personnel, books, journals and internet.^9,2,5

2. Eye exercises

· Palming- Rub your palms together. Form them into a cup-shape and place over the closed eyes for a minute. The heat will give relax to your eyes.

· Blinking- Practice to blink your eyes in every four seconds. It is difficult to remember so paste a poster on the backside wall indicating “blink, blink, blink” as a recall for blinking.

· Rolling- While working, close your eyes and roll them in circular motions for a minute. It will give an eye massage and lubrication to prevent eye dryness.

· Eye Scanning-Sit comfortably and observe the room. Start from one end and scan the outline of every object in the room. For e.g. start with a television set,then move on to the DVD player near it and then move on the window behind it. It will keep eyes in constant motion and help in maintaining eye focus.

· “10-10-10” rule- As per “10-10-10” rule means in every 10 minutes look an object at a distance of 10 feet for 10 seconds.¹⁰

3. Alternate rest breaks

People working on computers for prolonged time must take eye rest for 15 minutes after every 2 hours of continuous computer work to prevent eyestrain.⁴

4. Workplace light arrangement

Do not sit with the back facing an uncovered windows or doors. Use adjustable shades and curtains to control workplace light levels. At workstation lighting levels should be between 200 and 700 Lux (approximately 20 to 70 foot candles).²

5. Workplace modification/Ergonomics

The workplace should have adjustable well padded chair with arm support for typing and foot rest to keep the feet flat on the ground, moveable document holders, computers with detachable keyboards and screens to maintain the recommended posture.

6. Instructions regarding computer use

· Maintain a good sitting posture to avoid extra ocular problems related to CVS.

· Maintain a distance of 20 to 28 inches between the eyes and screen with a downward gaze angle of 15^o.

· Adjust the top of the screen below the horizontal eye level and slightly tilt back at 10^o-20^o away from the user.

· Adjust computer screen brightness and contrast to maintain balance with room lighting and screen visibility.

· For screen contrast, either use black characters on white or white characters on a black background as they are more visible than any other color contrast.

· Use bigger size font while reading on screen.

· Keep the reading material below the monitor while typing to avoid moving head between document reading and computer screen reading.

· Clean the computer screen regularly as per manufacturer’s instructions.

· Use personal protective equipments while working on computers such as special reading glasses, antiglare screens or filters.^2,5

Role of the nurses

Nurses are the backbone of the health care services. They have enormous roles to play in the prevention and management of CVS. Nurses must keep themselves up to date on current statistics, research and factual information on CVS. They can identify the high risk groups (e.g. IT professional, data entry operators, clerks, all other professionals working on computers). They can encourage the people for the correction of existing eye disorders (astigmatism, farsightedness, presbyopia and binocular vision etc) and treatment of systemic diseases that can affect the vision. They can refer them to ophthalmologist for a thorough eye checkup, visual acuity and refraction tests. For those who are diagnosed with CVS, they can instruct the instillation of eye medications as prescribed and proper cleansing of the eyes.

Nurses can demonstrate eye exercises (palming, blinking, rolling, eye scanning etc.) with instructions for the maintenance of correct posture for prevention of CVS. They can emphasize on the use of reading glasses, antiglare screens or filters while working on computers and avoidance of contact lens. They can advise regarding the diversion or recreational therapy to relieve eye fatigue. Nurses can recommend the use of talking books, tapes, records and machines if available. They can emphasize on the importance of follow-up visits and periodic eye checkups.

Nursing interventions for the management of CVS will include thorough eye assessment, education, and provision of comfort measures, rest, safety, adequate eye hydration and pain management. Nurse’s valuable collaboration and co-ordination with other member of the health care team will help to prevent and manage this emerging occupational hazard.

CONCLUSION:

Our eyes are the gateway to see this beautiful world. Thus, it is important to prevent and recognize the CVS at an early stage otherwise it may result in poor vision, work errors, absenteeism, loss of productivity and stress among the workers using computers.

ACKNOWLEDGEMENT:

The author would like to thank the respected vice –principal and faculty members of Murari Lal Memorial School and College of Nursing, Solan (HP) for their help in writing the present review.

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