Use of digital displays and ocular surface alterations: A review

Abstract

Digital display use has been accepted to be implicated as a contributing factor for dry eye disease (DED). Abnormal blinking during computer operation, including a reduced blink rate and an incomplete eyelid closure, increased palpebral fissure as consequence of high visualization angles, and meibomian gland dysfunction associated to long-term display use, are behind the increased prevalence of dry eye signs and symptoms found in digital display users. Previous research reveals significant reductions in tear volume and stability, alterations in tear film composition, including increased osmolarity, inflammatory cytokines, oxidative stress markers and reduced mucin secretion, eyelid abnormalities and ocular surface damage, encompassing corneal and conjunctival staining and bulbar redness, as a direct consequence of digital display use. In this regard, individual differences in the way that the various digital displays are typically set up and used may account for differences in their effects on induced dryness signs and symptoms. Furthermore, factors such as the use of contact lenses or inappropriate working environments, usually accompanying the use of displays, may significantly increase the prevalence and the severity of induced dry eye. Other factors, such as old age and female gender are also relevant in the appearance of associated alterations. Finally, clinicians should adopt a treatment strategy based on a multidirectional approach, with various treatments being applied in conjunction.

Introduction

The use of digital displays is ubiquitous and has become a common and essential practice in our everyday life. In 1995 there were 16 million internet users in the world (0.4% of the population), while nowadays they ascend to 4208 million (55.1% of the population) [1]. Numbers tend to peak amongst young people, with 91% of Europeans between 16 and 29 years of age using the internet [2]. New forms of digital displays, such as laptops, smartphones, tablets or even e-readers, have emerged, and the use of digital electronic screens is no longer restricted to desktop computers.

This tremendous change in work and life conditions experienced over the last decades has been accompanied by an increase in health-related complaints associated with the use of digital displays, which have been collectively termed “computer vision syndrome” (CVS) [3]. Dry eye-related symptoms, including eye burning, irritation, ocular dryness, tearing, tired eyes, foreign body sensation, and eye discomfort make one of the main groups of CVS symptomatology [4], and are often encountered in otherwise healthy patients [5].

In this regard, studies indicate a significantly higher dry eye symptom score in digital display users as compared to controls [6]. Many studies have also advised the relationship between the use of digital displays and tear film and ocular surface abnormalities [[7], [8], [9]]. For example, fluorescein break-up time (FBUT), non-invasive break-up time (NIBUT), and tear meniscus height (TMH) have all shown to be significantly lower among display users and to decrease with device use [[7], [8], [9]]. Similarly, oxidative stress markers in the tear film [7], inflammatory mediators [8] and tear osmolarity [9], have shown to be altered in computer users. Consequently, digital display use has been implicated as a contributing factor to dry eye disease (DED).

Obeying to a recent meta-analysis, the overall prevalence of DED in computer users is probably around 49.5%, and ranges from 9.5% to 87.5% [10]. This prevalence appears to be higher than the one observed in the general population, which, as indicated by the Tear Film and Ocular Surface (TFOS) Dry Eye Workshop (DEWS) II epidemiology report, is found to range between 5 and 50% at various ages [11].

The following review intends to summarize the current understanding regarding the effects of digital display use on the ocular surface and tear film, and their causal mechanisms. Additionally, it will disclose potential risk factors and possible treatments to be considered by the clinician.