In the past, children who did not constantly use digital devices did not have a noteworthy incidence of early onset refractory errors. However, the duration of screen usage has surged across all age groups worldwide, extending even to preschoolers—a trend accentuated by the COVID-19 pandemic. 

Digital Eye Strain (DES) or Computer Vision Syndrome has become an escalating concern globally, particularly among children. The American Optometric Association states that DES is “a group of eye- and vision-related problems that result from prolonged computer, tablet, e-reader and cell phone use.”

Computer vision syndrome. American Optometric Association.

 

 

An epidemic within a pandemic

 

The limitations on outdoor engagements and the shift toward home-based education contributed to a notable uptick in the utilization of digital devices by children.

 

 

Kids are hooked on screens

 

Today, children are experiencing higher risks of eye issues due to screen time, especially if they have a genetic predisposition for parental myopia.

Public health experts also worry about how excessive screen time causes sedentary behaviour in kids, affecting their physical and mental health. Children and teens growing up in the digital age, spend a significant amount of time on screens to play, learn, and even socialize, which could inevitably impact their developing brains and bodies.

Munsamy AJ, Chetty V, Ramlall S. Screen-based behaviour in children is more than meets the eye. S Afr Fam Pract (2004). 2022;64(1):e1–e4.

 

 

Additionally, screens emit glare from backlighting, which is absent in printed materials, further intensifying eye strain. 

 

Negative health effects of too much screen time

 

Dry eyes

The symptoms of DES are closely linked to those of dry eye syndrome. The reduced blink rate, common during prolonged screen usage, disrupts the tear film. Research indicates a significant drop in blink rate from 22 blinks per minute to 7 blinks per minute when using an electronic screen continuously.

Sheppard AL, Wolffsohn JS. Digital eye strain: prevalence, measurement and amelioration. BMJ Open Ophthalmology. 2018;3:e000146.

 

 

Sudden onset of vision errors

Excessive near-sighted work and prolonged screen time are linked with acute acquired concomitant esotropia (AACE) in children as young as 4 years old. AACE is a relatively rare form of strabismus marked by sudden onset of esotropia and diplopia.

Vagge A, Giannaccare G, Scarinci F, et al. Acute acquired concomitant esotropia from excessive application of near vision during the COVID-19 lockdown. J Pediatr Ophthalmol Strabismus. 2020;57:e88–e91.

 

Other common symptoms of DES in children, as reported in a Preventive Medicine review, include:

Mataftsi A, Seliniotaki AK, Moutzouri S, et al. Digital eye strain in young screen users: a systematic review. Prev Med. 2023;170:107493.

 

• Tired-looking, inflamed, red, and itchy eyes

• Foreign body sensation in the eyes

• Eye irritation with frequent rubbing of eyelids

• Excessive tearing or water in the eyes

• Blurring of vision

• Appearance of colored halos around objects

• Photophobia 

• Frequent headaches

Persistent vision issues

While most symptoms typically improve with reduced digital screen usage, some can endure, becoming permanent or persistent.

For instance, the American Optometric Association notes that blurred distance vision may persist even after screen time ends. Additionally, prolonged squinting due to glare sensitivity from bright digital screens can lead to eye strain, hinder reading speed, and contribute to short-sightedness, forming lasting vision abnormalities.

 

Aggravating factors

 

Pre-existing farsightedness, astigmatism, poor eye focusing, coordination issues, and age-related changes such as presbyopia can also contribute to visual symptoms of DES when using digital screens. 

The systematic review published in Preventive Medicine, which was commissioned by the World Society of Pediatric Ophthalmology and Strabismus, evaluated factors aggravating or alleviating DES symptoms in pre-presbyopic subjects using digital screens.

Overall, data from 1,171 children and 1,194 adults was assessed. The report found a positive association between neck pain, poor ergonomic parameters at work, and extended daily duration of digital device use with DES. Conversely, interventions such as blue filter lenses and adherence to the 20-20-20 rule showed no significant alleviating effects.

 

Prevention and management of DES

 

• Educate children, parents, and teachers about preventive measures, particularly for children at a higher risk of myopia, such as those with a family history of myopia or a lower hyperopic error compared to age-related norms, and those attending schools with excessive academic pressure.

• Encourage parents to instruct their children to take conscious breaks from screen time at home and school to support proper eye development. One effective strategy is the 20-20-20 rule, which suggests taking a break every 20 minutes looking at something at least 20 feet away for a duration of 20 seconds.

• Emphasize the importance of maintaining an optimal distance from books and screens. Advise individuals to keep an elbow-to-hand distance to prevent the screen from being too close to the eyes.

• Advise parents to limit their children’s recreational screen time, excluding school-related activities, to a maximum of 2 hours per day for school-aged children.