Secondary Logo

Journal Logo

Guest Editorial

Video display terminals - A wake-up call

Maskati, Quresh B

Author Information
Indian Journal of Ophthalmology: January 2022 - Volume 70 - Issue 1 - p 3-4
doi: 10.4103/ijo.IJO_2300_21
  • Open

Many facts about the use of video display terminals, cell phones, etc., and their ‘harmful’ effects on not only the eyes but also other parts of the body and the mind are well known. It is also common knowledge that teenagers and older ‘youngsters’ are the ones using these gadgets the maximum for both work and leisure activities as compared to the other age groups.

Various studies have also examined the role of the ‘blue’ light from computers and cell phones causing disturbances in circadian rhythms. Any kind of light, including that from ordinary lamps and our computer screens at night, can of course alter our sleep patterns or circadian rhythms. However, blue light is the most harmful.

A study from Harvard, for example, showed that blue light suppresses the release of melatonin (essential for proper sleep) twice as much as a green light when the lux or luminance from both was the same.[1]

In another interesting study from the University of Toronto, Canada, researchers found that the use of blue light blocking eyewear by subjects exposed to bright light caused an equal drop in melatonin as the subjects without protective eyewear exposed for the same length of time to dim light—it makes a case for blue light protective eyewear for those working long hours in artificial light, especially at night.[2]

What sets this Indian study apart is the good analysis of statistical data derived from simple questionnaires filled in by college-going girl students.[3] The authors conclusively prove a connection between dry eye and sleep disturbances on one hand and increased screen time on the other. If the study had stopped just there, it would have still been useful to fellow researchers. However, the authors have gone a step further and looked for a connection between the above and family income, whether there is a single working parent, and what stream of education the young person is pursuing, which I feel was not relevant. Eliciting a history of smoking and tobacco chewing may be more informative. A study has shown almost 10% of dry eye adult patients were smokers or tobacco chewers.[4] Sometimes, dealing with too many variables makes the average reader miss the wood for the trees!

It is not very clear why the study was only restricted to the female college-going population. Perhaps a similar study can be done among the males of the same age group later. However, this does not detract from the usefulness of this study. In these COVID-19 times, with schools and colleges in most parts of India showing no signs of returning to traditional classroom teaching, increased screen time is bound to occur in the youth.

A study among 240 college students, both males and females, revealed a 50% prevalence of dry eyes in those using video display units (VDU). Interestingly, an overwhelming majority of these students were using VDU for less than 4 h a day![5]

The website of Harvard Medical Publishing suggests some useful tips to reduce the dangers of blue light at night.[1] Among them are

  1. Use dim red lights as night lamps instead of white or yellow as red light suppresses melatonin the least.
  2. “Avoid looking at bright screens beginning 2–3 h before bed.” This of course may not be very practical for those who are college students studying for an examination like those in the study.
  3. If you must work on your laptops or other gadgets at night, invest in blue-blocking filters on your screen or in your spectacles. The jury is divided on this, however, with the American Academy of Ophthalmology website categorically stating that blue-blocking filters are an unnecessary expense with a low-cost benefit ratio.[6]

Our policymakers have to balance the increased risk of COVID-19 spread with the deleterious effects of “study from home,” taking the percentage of fully vaccinated youth in each district into consideration. Decisions should be made at the district level rather than a pan India ‘fatwa’ issued by the center to keep educational institutions open or closed.

Articles such as these serve as wake-up calls for many of us ophthalmologists as well. We need to talk to the youth who come to us for computer vision syndrome a bit more. Eliciting the history of sleep disturbances and head and neck issues, appetite and mood changes, and then, acting as counselors will be far more effective than prescribing a lubricant to be used as required. A small percentage of these patients may need the services of psychologists and experts in other specialties. We have to convince these patients to seek additional assistance and not dismiss their complaints as trivial, if we are to make some dent in the burgeoning but silent epidemic being caused by computers, cell phones, etc., in our young and vulnerable population.

About the author

Dr Quresh Maskati

Dr. Maskati is in private practice as a Consultant Eye Surgeon and Director, Ocular Surface and Cornea Service, Maskati Eye Clinic, Mumbai since 1986. He has written chapters in 12 textbooks, published several papers in peer reviewed journals and authored a public awareness book “Simplifying Eye Care”, which is in its third edition. He is the only ophthalmologist in the world with experience in both the Pintucci and the Boston Keratoprosthesis. He has been the youngest President in the history of the Bombay Ophthalmological Association and the Maharashtra Ophthalmological Society. He was the President of All India Ophthalmological Society for 2014-15. He was also the President of the Cornea Society of India and International Society for Manual Small Incision Cataract Surgery (2017-19). He is currently the President of the South Asian Pediatric Ophthalmology and Strabismus Association. He has addressed various international and national conferences as faculty, teaching various aspects of eye care and has performed live surgery in several neighboring countries such as Malaysia, Philippines, Sri Lanka, Bangladesh and Pakistan, besides various cities in India. Dr Maskati is an able administrator, an academic leader and an astute clinician, and is part of the Editorial Board of Indian Journal of Ophthalmology.


1. Staying healthy: Blue light has a dark side, July 7, 2020 Website of Harvard Health Publishing, Harvard Medical School Available from:
2. Rahman SA, Shapiro CM, Wang F, Ainlay H, Kazmi S, Brown TJ, Casper RF Effects of filtering visual short wavelengths during nocturnal shiftwork on sleep and performance Chronobiol Int 2013 30 951 62
3. Gupta PC, Rana M, Ratti M, Duggal M, Agarwal A, Khurana S, et al. Association of screen time, quality of sleep and dry eye in college-going women of Northern India Indian J Ophthalmol 2022 70 51 8
4. Bhatnagar KR, Sapovadia A, Gupta D, Kumar P, Jasani H Dry eye syndrome:A rising occupational hazard in tropical countries Med J DY Patil Univ 2014 7 13 8
5. Kolla A, Dahariya D, Ram MS, Kolla V Prevalence of dry eye in college students at Uparwara community in Raipur Int J Community Med Public Health 2019 6 3768 70
6. Porter D Blue Light and Digital Eye Strain Available from: Last accessed 08-Dec-2021
Copyright: © 2021 Indian Journal of Ophthalmology