Ms Tsering lamu shongmu, Master’s in Optometry

Assistant Professor, Assam Downtown University, Guwahati, India.


The coronavirus disease (COVID-19) pandemic has forced significant lifestyle changes, including increased exposure to digital devices. On March 25, 2020, India has confined to a national lockdown that resulted in the shutdown of services such as schools, colleges, and most workplaces. The outbreak has changed the conventional method of teaching, the use of smartboards in e-learning courses supported by digital devices. People have been forced to work from home and e-learning has become the new norm for students. (1) People worldwide are increasingly using electronic devices to connect socially, for education, and at work. During the COVID-19 pandemic, the use of technology in classrooms has increased significantly. Consequently, harmful habits related to digital devices, such as prolonged use of a computer, tablet, and smartphone, have emerged. The digital eye syndrome is caused by the ongoing use of electronic devices, especially at near working distances. (2,3) A computer vision syndrome (CVS), also referred to as digital eye strain defines a group of vision and eye-related problems associated with ocular and non-ocular symptoms that result due to prolonged exposure to a computer screen, cell phone, tablet and/or, e-reader. According to the American Optometric Association (AOA,1995), computer vision syndrome has been defined as a complex of eye and vision problems related to the activities which stress near vision and which are experienced during the use of computers(4). When we look at a nearby object, the eyes will undergo miosis, accommodation, and convergence. Hence, extensive work on computer screens has been associated with changes in both relative accommodation and vergence. Eye strain is directly proportional to the duration of screen working time.(5) Hence, the prevalence of eye strain, which was found to be higher among students taking online classes compared to the general public, indicates an increase in screen time during the pandemic, especially among students attending online classes.(5)Long hours ahead of these devices can cause many ocular symptoms such as asthenopia, blurred vision, red eyes, burning sensation, excessive tearing, double vision, headache, light sensitivity, glare, slowness in changing focus, and changes in colour perception, which can be seen when the demands of the task exceed the abilities of the individual. Symptoms may vary based on a variety of factors, such as the amount of time spent on the computer, viewing distance, seating position, computer screen height, and any underlying visual acuity issues. A shorter screen distance has been associated with a higher risk of dry eye syndrome in children. (6,7) Long periods of study and regular usage of digital displays can expose the corneal surface to the screen, and inadequate and sluggish blinking can impair the integrity of the precorneal tear film, resulting in dry eye disease/symptoms that are strongly linked to CVS. In the paediatric population, symptoms such as tears, eye redness, eye rubbing, and headache may suggest screen time-related dry eye.(8) It has been reported that the blink rate during computer use reduces to 3.6 blinks/min as compared to normal mean blink rate, i.e.18.4 blinks/ min.(9)  Ocular symptoms including eye strain, itching, and burning sensation are more common in computer users for more than 6 hours.(10) The wavelength of blue light emitted by light-emitting diode (LED) displays stimulates the retinal photoreceptors, causing disturbed circadian rhythms and suppression of production of melatonin from the pineal gland, thus delaying the latency of sleep onset as well as affecting the quality of sleep.(2,3,11) Extremely low refresh rates (high flickering) are known to be associated with headache, fatigue, irritability, and epileptic seizures.(12) Others symptoms like Neck and shoulder pain may be associated with a poor sitting position for long hours.



  1. Times H. Coronavirus: UGC constitutes committee for promoting online learning. Accessed August 8, 2020.
  2. Sheppard AL, Wolffsohn JS. Digital eye strain: Prevalence, measurement, and amelioration Open Ophthalmol. 2018;3(1), e000146. https://doi. org/10.1136/bmjophth-2018-000146
  3. Coles‐Brennan C, Sulley A, Young G. Management of digital eye strain. Clin Exp Optom. 2019;102(1):18–29.
  4. American Optometric Association. Computer vision syndrome. (accessed 28 April 2020).
  5. Pratyusha Ganne, Shaista Najeeb, Ganne Chaitanya” Digital Eye Strain Epidemic amid COVID-19 Pandemic” – A Cross-sectional Survey, (2021). Ophthalmic Epidemiology, 28:4, 285-292
  6. Shantakumari N, Eldeeb R, Sreedharan J, Gopal K. Computer use and vision. related problems among university students in Ajman, United Arab Emirate. Annals of medical and health sciences research. 2014;4(2):258-63.
  7. Kanitkar K, Carlson AN, Richard Y. Ocular problems associated with computer use: The ever-increasing hours spent in front of video display terminals have led to a corresponding increase in visual and physical ills. Rev Ophthalmol E-Newsletter 2005;12.
  8. Wu, S. Z., Chong, J. K., Tracer, N., Wu, M., & Raju, L. (2020). Prevalence of dry eye symptoms and relationship to screen time in a New York City pediatric population. Investigative Ophthalmology & Visual Science, 61(7), 340-340.
  9. Association AO. The effects of computer use on eye health and vision. Internet: http://www. aoa. org/documents/Effects Computer Use. pdf [02 August 2011], 1997. Accessed on 4 November 2020.
  10. Agarwal S, Goel D, Sharma A. Evaluation of the factors which contribute to the ocular complaints in computer users. Journal of clinical and diagnostic research: JCDR. 2013 Feb;7(2):331.
  11. Jaiswal S, Asper L, Long J, Lee A, Harrison K, Golebiowski B. Ocular, and visual discomfort associated with smartphones, tablets, and computers: what we do and do not know. Clinical and Experimental Optometry. 2019 Sep;102(5):463-77.
  12. Anshel J, editor. Visual ergonomics handbook. CRC Press; 2005 Jun 22.

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