Video display terminal use and dry eye: preventive measures and future perspectives

Abstract

Background: Dry eye disease (DED) is a common cause of ocular pain and discomfort. Dry eye disease (DED) stems from a loss-of-tear film homeostasis and is frequently seen in video display terminal (VDT) users. Video display terminal (VDT) use reduces blink rates and increases incomplete blinks, leading to tear film instability and ocular inflammation, promoting DED.

Purpose: To assess and evaluate the methods for preventing VDT-associated DED and ocular discomfort.

Methods: Studies were found using PubMed and Embase with the search terms: (digital visual terminal* OR computer use OR screen use OR smartphone OR display OR visual display terminal* OR computer vision syndrome OR tablet OR phone OR screen time) AND (dry eye OR DED).

Results: Thirty-one relevant articles were found. Ten described single-visit studies, whereas 21 had a prolonged follow-up. Most preventive measures of VDT-associated DED aimed to increase blink rate or directly prevent tear film instability, ocular inflammation, mucin loss or ocular surface damage. Using an adjustable chair and ergonomic training, blink animations and omega-3 supplementation improved signs and symptoms of VDT-associated DED. Taking frequent breaks was associated with fewer symptoms, but no study assessed the commonly suggested 20-20-20 rule.

Conclusion: Preventive measures, such as blink animation programmes, oral intake of omega-3 fatty acids and improved ergonomics act on different parts of the vicious cycle of dry eye and could supplement each other. A comparison of the efficacy of the different interventions as well as more evidence of the effect of increased humidity, VDT filters and ergonomic practices, are required.

Keywords: computer vision syndrome; dry eye disease; ergonomic practices; preventive measures; tear film stability; video display terminal.

Fig. 1

Vicious cycle of dry eye disease. Video display terminal (VDT) use leads to decreased blink rates and increased incomplete blinks, promoting tear film instability, tear evaporation rates and hyperosmolarity. Hyperosmolarity can increase inflammatory mediators that damage the ocular surface and goblet cells. The loss of goblet cells decreases mucin secretion and further reduces tear film stability, leading to a self‐perpetuating vicious cycle. Copyright Sara T. Nøland. [Colour figure can be viewed at wileyonlinelibrary.com]

Fig. 2

Illustration of the ocular protection index (OPI). The OPI is calculated by dividing the tear film break‐up time (TBUT) by the inter‐blink interval (IBI). In this illustration, two scenarios are presented: blinking during normal conversation (above) and during video display terminal (VDT) use (below). During a normal conversation, the IBI is generally shorter than, or close to, TBUT, due to high blink rates, making OPI closer to 1. During VDT use, IBI increases, and TBUT decreases, reducing the OPI and yielding an unprotected ocular surface. Copyright Sara T. Nøland. [Colour figure can be viewed at wileyonlinelibrary.com]

Fig. 3

Overview of search strategy and selection of articles.

Fig. 4

Illustrations of angle of gaze: The angle of gaze on the screen changes how exposed the ocular surface is between blinks. Copyright Sara T. Nøland. [Colour figure can be viewed at wileyonlinelibrary.com]

Fig. 5

Illustration of video display terminal (VDT) filter. Screen without VDT filter, illustrating glare (left). Screen with VDT filter, showing reduced glare (right). Copyright Sara T. Nøland. [Colour figure can be viewed at wileyonlinelibrary.com]

Fig. 6

Illustration of the vicious circle with preventive measures. The outer circle shows the target of the different preventive measures. Copyright Sara T. Nøland. [Colour figure can be viewed at wileyonlinelibrary.com]