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Computer Vision Syndrome (CVS) Clinic


What is Computer Vision Syndrome (CVS)/ Digital Eye Strain (DES)?
What are the common symptoms of CVS?
What causes CVS?
Who can be affected by CVS?
Is there any age limit for CVS?
Can proper glass power be a solution to CVS?
How can it be detected?
What is the best way to treat CVS?
Can it be prevented?
What can be the negative effects of CVS?
Where can I get myself tested for CVS?
What are the services provided by the clinic?
When should I get myself tested for CVS?
How frequently will I have to visit the clinic?
How do I get myself tested or take an appointment?
Are there any points to be followed before taking up the CVS examination?

What is Computer Vision Syndrome (CVS)/ Digital Eye Strain (DES)?

Computers, mobile phones and gadgets (Visual Display Units - VDUs) are now an integral part of our day.

This advancement of science has brought about a vast change in our lives that we wonder what life would have been without it!

With all its benefits come certain health related issues, awareness of which is minimal.

The human eye was designed for more of distance work and we sailed through centuries with minimal difficulties as the eyes could adapt to the changes in our near tasks.

The transformation from hunting in the open to working on paper has been slow and gradual and put not much stress on the visual system.

But the shift from PAPER to VDUs has been so rapid and strong that the eye has not adapted to the new demands put on it to work at NEAR in a new visual environment for extensive hours and in stressful environments.


Computer Vision Syndrome (CVS) is a complex of eye and vision problems related to near work which are experienced during or related to computer use.

CVS is characterized by visual symptoms which result from interaction with a VDU or its environment

When the demand at near work exceeds the normal ability of the eye to perform the job comfortably, one develops discomfort and prolonged exposure to the discomfort leads to a cascade of reactions that can be put together as Computer Vision Syndrome.

Near work here refers to the use of all the self illuminating PCs, mobile phones, and the latest gadgets that have helped bring the web world and quick computation to our hands.

The chief source of the problem lies in it being a Repetitive Stress Injury to the visual system which means, rectifying the source of stress is overlooked.

What are the common symptoms of CVS?

The most common symptoms are
• Eyestrain
• Headaches
• Blurred vision
• Difficulty in changing focus between far and near
• Dryness of eyes
• Irritated eyes
• Tired eyes
• Redness
• Contact lens discomfort

Neck, shoulder and backache can also be related to the way we use our eyes at the computer.

What causes CVS?

There are several contributory factors for Computer Vision Syndrome to develop.

To state a few:

• Uncorrected spectacle power
• Inappropriate glasses for computer use
• Difficulty in eye coordination at near work
• Strain on the muscles of the eye due to work style
• Decreased blink rate or tear function
• Glare and reflections from the monitor and surroundings
• Poor workstation setup or improper use of workstation
• Job nature and stress

Who can be affected by CVS?

Computer Vision Syndrome affects 75% of the people who work on VDUs, most markedly those who work more than 3 to 4 hours with VDUs. This includes all professions that use computers (IT, BPO, Accounting, banking, front office) students and children who

• Work at the computer for more than 3 hours a day
• Have strain at computer work.
• Experience any or all of the symptoms of CVS stated
• Experience stressful situations associated with work

Is there any age limit for CVS?

CVS can occur in any age group but children are found to report less of symptoms.

This does not indicate that children are not prone to CVS, but that they continue to strain the visual system and the condition is overlooked to a greater extent than adults.

The visual system in teenagers is well adapted to near tasks, but the strain due to change in image quality, glare, lighting and absence of breaks between VDU use, associated with muscle imbalances and power changes need a closer watch as it is the changing phase of physical development and no chances can be taken.

Can proper glass power be a solution to CVS?

There is no single type of computer glasses that fits all or is the best for everyone.

A pair of computer glasses should include:
• The prescription measured at the computer working distance
• The appropriate lens type for the patient
• A tint where required
• An anti-reflective (AR) coating
• Prisms, if needed

The spectacle of a computer user by itself needs specialized evaluation to keep vision comfortable.

The spectacle alone does not address a myriad of other problems the eye can face at the computer due to CVS.

How can it be detected?

CVS is often different from other typical eye problems.

The usual ophthalmic examination focuses more on distance vision (6 m and beyond) and near vision (35 to 40 cm), whereas the computer users have a unique working distances with respect to the monitor, keyboard, mouse, etc.

Due to this difference in working distance, the usual examination does not completely address the actual environmental conditions.

The Computer Vision Clinic, however, is specially designed to address the varied needs of the individual computer user.

The testing required for detecting CVS are:
• Refractive error correction for computer workstations or other VDUs
• Evaluation of arrangement of the computer workstation or environment
• Evaluation of lighting and reflections
• Eye health evaluation
• Analysis of visual functions at near working distances

A detailed clinical evaluation, besides a thorough documentation of the work surroundings and job nature with the help of questionnaires and interactive sessions are essential for this.

What is the best way to treat CVS?

There are three phases in the management of CVS when you seek professional help

• Detection
• Management
• Follow-up

The best way to treat CVS is to identify the conditions that have contributed to the symptoms and address them.

The earlier the condition is detected the more it acts as a preventive measure.
Ideal ocular status and proper ergonomics both visual and environmental could keep the condition under check. Management is minimal and modifications become the answer. The frequency of follow-up is also reduced as the condition is easily reversible.

A delay in detection means signs which have set in more deeply and a greater effort is required from the clinician and the VDU user to first program a schedule to rectify the damages to the maximum possible extent and then work towards reducing the source of repetitive stress or altering it favorably without affecting work or the eyes.

In this situation frequent follow-ups are essential to ensure proper management of the ocular condition and assess the effect of the work related changes on the eye.

The adage “PREVENTION IS BETTER THAN CURE” seems to best fit CVS and eye care.

Can it be prevented?

Yes. CVS can be prevented.

The first step towards prevention is to be aware.
CVS sets in often due to the assumption that mild discomfort is inevitable at VDU work. The early signs are overlooked and this gives way to stronger problems.

Awareness of what is ideal for the eye and visual system to work comfortably is thus the first step. The web is a great source of information for this awareness. But improper use of the information and poor understanding of the intricate visual process can often lead to more discomfort than we could tell.

This is where professional counsel comes in handy to educate ourselves on the best ways to utilize our ocular and ergonomic resources with the least effect on the human body.

Awareness alone, again, does not solve the problem.

An evaluation can give us an answer to the reason for the difficulties, but strict adherence to the rules to fitness of the eye is as important as the care given to the management of systemic diseases.

No one knows better about the effect of eye strain and discomfort on the quality of work than one who has been affected by it. One has to just look around to see the real picture. The confusion, the tension and the nervous wreck one becomes when the strain goes to your head cannot be far from the eyes.

Simple steps to keep the repetitive stress injury away could be the magic word for the beginner at computer work

What can be the negative effects of CVS?

• Poor visual functions
• Increased stress levels
• Reduced effective work hours
• Frequent absence from work
• Possible increase in errors
• Less time available for personal care and reversal

which together spell ….
“Reduced productivity”

Not just the organization you work but you personally could feel less effective at work for a condition that could so easily be set right with a little care.

Where can I get myself tested for CVS?

In Chennai you can get yourself evaluated at Computer Vision Syndrome Clinic (CVC) at Sankara Nethralaya – College Road

The Computer Vision Syndrome Clinic (can we say The Computer Vision Clinic) that treats Computer Vision Syndrome, initially located at Mandaveli,Sankara Nethralaya’s satellite center started its service from 1st August’2003, which was the first of its kind in India.

The clinic also caters to the visual needs of the symptomatic computer user of organizations that routinely send their employees for CVS evaluation. Patients are also referred to this clinic after receiving a general eye examination from their primary eye care provider.

What are the services provided by the clinic?

Computer Vision Syndrome Clinic (CVC) examination – which includes
1. A complete eye examination – including spectacle power
2. Orthoptic evaluation – Ocular muscle coordination and status evaluation
3. Tear function evaluation
4. Work stress and ergonomics assessment.
5. Counseling on work and ergonomics
6. Exercises for Binocular vision problems
7. Review of progress and maintenance of visual and ergonomic conditions

Advanced vision or ergonomic assessment - some patients require special review visit, depending on the visual and ergonomic analysis and treatment required

Ergonomic evaluations - Assessment of workplace ergonomics with recommendations for organizations for computer work and workstations

Employee vision screening - On site visual system evaluation of computer using employee

Awareness programs/ Seminars - How to manage CVS / Eye Care

Annual CVS check – Regular CVS evaluation of employees of institutions that have incorporated eye health care in their regular health care protocol in the IT industry etc

When should I get myself tested for CVS?

The ideal time for a CVS evaluation at the CVS Clinic would be at the beginning of one’s career which involves extensive computer work.

An evaluation would help detect problems in the eye which would get worse with improper computer use. These when rectified would reduce the intensity of discomfort with long hours of computer work.

If this has not been possible the best time is
- ANY TIME one learns about CVS or has its symptoms.

How frequently will I have to visit the clinic?

The follow-up with the clinic would depend on how good the condition of your eye or your workstation is.

If only basic changes are required a review would be required after 2-3 weeks to verify if you are comfortable. And then review after a year for a routine evaluation.

If the CVS related factors are advanced you will have to come for reviews based on the extent of your recovery which would be 1 – 3 months or as required based on your individual condition.

A review evaluation is required every year for anyone who works at near as the demand on the visual system is high as we age and prevention is the best way to reduce damage as the work demands never reduce.

How do I get myself tested or take an appointment?

For any vision related discomfort you encounter in using your computer please call Sankara Nethralaya to schedule your appointment with highly skilled professionals to address your CVS problems.

Contact Details:

Sankara Nethralaya,
18 College Road,
Chennai-600 006
Phone: 044- 28271616

Are there any points to be followed before taking up the CVS examination?

Please come prepared for the testing with your detailed eye and general health reports and your spectacles.

Ensure that you discontinue wearing your Contact Lenses at least 24 hours before your test date and bring them along with you.

For queries on CVS you can mail:

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