Digital Eye Strain (DES) refers to a cluster of ocular and vision-related problems attributed to the prolonged usage of desktops, laptops, mobile phones, tablets, e-readers, and storage devices. The lockdown during the COVID pandemic made e- learning mandatory and the prevalence of DES among children was an alarming 50-60%. One of the most significant complications was the development of new onset myopia necessitating use of glasses and also progression of preexisting myopia.

Symptoms

1. Eye discomfort: Watering / redness/ itching of eyes/ dry eyes

2. Eye strain/ Difficulty in focusing

3. Episodes of blurred vision which improves after rest

4. Glare/ excessive sensitivity to light

5. Headache/ neck pain/ back pain

Pathophysiology

1. Devices such as mobiles/ computers/ laptop emit short high energy waves that can penetrate the eye and may damage the retinal cells.

2. Visual work on a digital screen demands continuous focusing and refocusing in an attempt to see the pixelated characters clearly. Frequent eye movements to maintain focus lead to fatigue and eye strain

3. Prolonged screen time leads to reduced blink rate which leads to dryness, redness and gritty sensation in the eyes. Typically, we blink 14–16 times a minute,

but this reduces to 4–6 times a minute when using screens.

4. Poor lighting / Incorrect distance between the eye and screen leads to unnecessary forward bending causing posture related problems

 Management and Preventive strategies

Recommendations to reduce DES include the following

1. Average daily screen time should be limited to < 4 hours

2. Following the 20-20-20 rule : After every 20 minutes spent using a screen; you should try to look away at something that is 20 feet away from you for a total of 20 seconds

3. It is advised to sit upright at a desk or table with screens approximately 20 inches from the eyes. The height of the screen should be positioned lower than the height of the eyes, such that the viewing angle is 15-20 degrees below eye level.

4. Frequent blinking of eyes reduces the chances of developing dry eyes.

5. The reference materials should be placed above the level of keyboard and below the level of the monitor.

6. Environments with an illumination of over 1000 lux are known to decline user performance.

7. A contrast setting of around 60–70% is considered comfortable by most people. The brightness should be adjusted such that the light coming from monitors matches the light in the surrounding workplace. Anti-glare screens may also help in reducing the amount of light reflected from the screens . A clearly legible font of at least size 12 preferably in a dark color over light background should be chosen. Screen time tracking allows to one to control excessive screen usage. It encourages to spend less time on digital devices.

8. Refractive error correction and use of glasses with antireflective coating

9. Public education about the lasting effects of excessive screen time and encouraging healthier lifestyle practices.

10. Parents should be counseled to monitor their child’s screen usage and incorporate family time.

11. Encourage children towards outdoor recreational activities

DES is an emerging health problem and there is evidence that increased screen time is associated with higher risks of an unhealthy diet, cognitive outcome, interpersonal relationships, and quality of life. With the recent explosion of digital electronic device usage among children and adults, there is a need for creating awareness among the public about limiting digital screen time and implementing ergonomic practices of screen exposure.