The COVID-19 pandemic has had a tremendous impact on our everyday lives. Most people are quarantined at home, leading to an increase in near work and the use of smart devices, both of which create visual difficulties. Computer Vision Syndrome (CVS) has been identified in roughly 60 million people worldwide, according to a 2016 study [1]. CVS is a group of visual and extraocular symptoms linked to the continuous use of Visual Display Terminals (VDTs) [2]. Some of these common symptoms include visual and ocular symptoms, sensitivity to light, asthenopia, musculoskeletal symptoms, and other general symptoms [3]. Some of these visual symptoms are related to blurry vision, such as post-work distance blurred vision, constant and intermittent blurred vision, the most Ocular surface symptoms are itching, foreign body sensation, and burning sensation [2, 3].

People who spend more than 4 hours every day in front of a VDT are more likely to develop dry eye diseases [3]. This ocular symptom is often caused by dysfunctions of the meibomian gland [3]. Some of the patient's ocular complaints include excessive blinking and tearing [4]. According to a previous study, the prevalence of asthenopia is estimated to be approximately 55% and 81% among gadget users, the condition causes several binocular anomalies, including near point of convergence removal, phoria deviation in the near vision, and some accommodative responses can be inaccurate [2]. These responses are temporary and do not have any permanent effects on accommodation responses [5]. Musculoskeletal symptoms, such as neck, back, and shoulder pain, are associated with the prolonged use of computers [2]. VDT users in previous studies [6-8] showed that eye-related symptoms are the most common health problems [6-8]^. All the previously described symptoms of CVS are included in the American Optometric Association clinical definition as “the combination of eye and vision problems associated with the use of computers^”[9, 10]. Asthenopia is considered the most common complaint in patients with CVS. Asthenopia symptoms include strained and tired eyes, ocular surface-related symptoms include dry eyes, watery eyes, irritation, redness, and foreign body sensation, also visual-related symptoms include blurred and double vision [8-10].

In 2008, study results of over 400 computer operators in India reported asthenopic symptoms almost in 46.3% of participants [11]. A study of 35 Mexican computer terminal workers found an even higher prevalence of symptoms, with 68% of the subjects experiencing symptoms due to prolonged VDT [12]. In addition, a study in Australia of more than 1000 computer workers showed that 63% of the subject's reported symptoms of uncontrolled conditions; this number decreased to 25.2% after some adjustments that include the introduction of an optimized ergonomic desk and more frequent work breaks [13]. It is not clear yet if asthenopia symptoms caused by extended computer usage are related to age [11, 13, 14]. Females appear to have a higher prevalence as compared to males [15, 16].

While the electronic screen represents one visual target, a hard paper copy can also behave as a visual target. However, the evidence shows that the two forms of the target presented are not equivalent to each other. For instance, [17] the performance of subjects on an editing task with the material presented either as a VDT or in hard copy form. the evidence shows that with the hard copy presented, subjects make fewer errors and perform the task faster as compared with the VDT subjects. Other studies have reported matching results with fewer errors made by participants when viewing printed materials [18-20]. According to the Sixth European Working Conditions Survey, almost more than 50% of European workers use VDTs at work, with 37% using VDTs no less than three-quarters of the workday [8, 21, 22]. Therefore, the impact of VDTs on ocular health is a relevant area of study. However, the studies published so far have a huge limitation in evaluating CVS through invalidated or unstructured questionnaires, which include different symptoms according to the author and imprecise definitions of when the subjects should be characterized as symptomatic, tremendously compromising the findings of the studies [23-25]. Therefore, the current study aimed to assess the impact of excessive use of digital devices during the pandemic of coronavirus among the Saudi population.

During the coronavirus pandemic, many people were quarantined at home to maintain social distance and avoid spreading the disease [7-10]. Accordingly, smart devices were used increasingly for prolonged periods, causing a potential upswing in CVS, an umbrella term for several visual disorders that affect 60 million people worldwide [12-17]. People are more likely to experience the risk of dry eye disease and the disruptive symptoms that go along with it if they work in front of a VDT for more than 4 hours per day [1, 2, 3]. Therefore, the current study aimed to assess the impact of excessive use of digital devices on the eyes during the coronavirus pandemic in the Saudi population.

The results of these studies showed that approximately 94% of the participants used a mobile phone. Nearly half of the participants (48%) did not have any symptoms of eye dryness while 52% experienced eye dryness symptoms (22.3% had mild, 13.7% had moderate, and 15.9% had severe symptoms), according to the OSDI score. It was reported that most of the participants did not feel foreign body sensations, pain, strained eyes, blurred vision, or poor vision during quarantine. Their eyes did not limit them from doing their daily activities of reading, driving at night, working on a computer, or even watching TV. The majority did not recently experience blurry vision or momentary double vision. These findings agree with previous studies that reported that mobile phones were the most used digital devices among all age groups during coronavirus lockdown [26, 27]. A previous study reported that the prevalence of asthenopia symptoms was higher among women than men, which is in line with our study results; among those who had mild symptoms, 54.2% were females, and 45.8% were males [15, 16].

Our results showed a significant association between age and the development of eye dryness symptoms (p=0.02), which disagreed with other studies in which there was no association between asthenopia symptoms and the age of the subjects [11, 13, 14]. Additionally, the current study showed a significant correlation between eye dryness and sex, having thyroid diseases, taking antidepressant medications, taking multivitamins, and using contact lenses. However, a logistic regression model of risk factors associated with severe dry eye symptoms revealed that wearing contact lenses was the most significant variable (p<0.0001) among the participants. A previous study reported several symptoms of eye dryness among mobile device users during the coronavirus lockdowns [11-20]. These symptoms, such as watering eyes, dry eyes, shoulder pain, headache, and back pain, were significantly associated with hours of using digital devices per day (p<0.05). Pain behind the eyes and itching eyes are the major symptoms among participants engaged in digital activities for prolonged periods. Additionally, some subjects complained of excessive tears and a high blinking rate due to the long-time use of digital devices [4]. Previous studies reported that the prevalence of asthenopia ranged from 55% to 81% among gadget users [5].

The prolonged use of gadgets may result in several binocular anomalies, such as the deficiency of near point of convergence, phoria deviation in near vision, and inaccurate accommodative responses [2-7]. All these modifications are temporary but do not have any permanent effect on accommodation. Prolonged use of digital devices has been reported to increase the prevalence of dry eye symptoms. A study reported that approximately 91% of the participants experienced dryness symptoms associated with excessive digital device usage, but this percentage was much higher than another study conducted in 2014 hence, the prevalence of symptoms was 81.9% and 78.6% for engineering students and medical college students, respectively [28]. This significant shift occurred due to the increase in the duration of digital device usage of the participants during coronavirus lockdown, estimated to be an average of 8.9 ± 3.63 hours of usage per day [28]^.

Facial masks are commonly used during the pandemic of coronavirus and this may be associated with increased dry eye and ocular symptoms [29]. However, in the current study, the facial mask was not considered a factor for assessing the dry eye symptom may have been considered as a limitation of this study. The current study has some limitations. First, it was a community-based cross-sectional study and was conducted online; consequently, the collected data was sometimes incomplete. To decrease the bias of the questionnaire, incomplete questionnaires were excluded from the final report. Furthermore, the participant response rate was slightly low, which reflects that not all the invited participants participated in the study. Second, the current study did not consider the facial mask as a factor for assessing the dry eye symptom may have been considered a limitation of this study All the above-mentioned limitations notwithstanding, the current study provides information about the impact of excessive use of digital devices during the pandemic of coronavirus among the Saudi population.

This study highlighted the potential increase in the use of different digital devices during the coronavirus pandemic lockdown and its adverse impact on ocular health among different age groups. There was a significant association found between age and development of eye dryness symptoms, with eye dryness symptoms increasing during quarantine. The previous findings suggest that it is important for digital device users to learn preventive measures from practitioners in eye healthcare, in order to reducd the effect of eye dryness. More studies should be conducted to assess the impact of digital device usage on all age groups, starting from children up to the elderly population.