Change in tear film characteristics in visual display terminal users

Effectiveness of an Acupuncture Steam-Warming Eye Mask on Dry Eye Disease in Visual Display Terminal Users: A Prospective Randomized Controlled Trial

We aim to evaluate the effectiveness of an acupuncture steam-warming eye mask (ASEM) on dry eye disease (DED) in visual display terminal (VDT) users. This prospective randomized clinical trial included VDT users with DED-related features who were randomly assigned to the ASEM group (ASEM for 2 weeks, 20 participants) or the steam-warming eye mask (SEM) group (SEM for 2 weeks, 20 participants). The tear film break-up time (TBUT), Schirmer test, tear meniscus height, ocular surface staining scores, eyelid and meibomian gland exam, subjective symptoms, and quality of life (QoL) scores before and after treatment were collected. A generalized linear mixed model was applied to compare the improvement of symptoms and signs between the two groups. After the 2-week treatment, all the subjective symptoms and questionnaire scores in the ASEM group improved significantly (all p < 0.05), whereas the feelings of relaxation, comfortable, and refreshment did not change in the SEM group (both p > 0.05). The TBUT, tear meniscus height, and meibum quality in the lower eyelid were significantly better in the ASEM group than the SEM group (all p < 0.05), whereas no significant changes were observed in the Schirmer test and ocular surface staining scores. Compared with the SEM group, the ASEM group experienced a stronger feeling of refreshment (p = 0.013), lower sensation of ocular discharge (p = 0.031), higher TBUT (p = 0.045), better meibomian gland expressibility of both eyelids (both p < 0.05), and better meibum quality of both eyelids (both p < 0.05), even after adjustments for age and sex. In conclusion, comparing with SEM, ASEM can improve some subjective DED symptoms, tear film stability, and meibum status in VDT users.

Ocular surface changes following computer use in post-LASIK patients

PURPOSE

To assess the impact of computer use on the ocular surface of individuals after laser in situ keratomileusis (LASIK).

METHODS

The dry eye symptoms and ocular surface of 18 post-LASIK young individuals and 18 controls were evaluated before and after performing a 30-min task on a computer without (Visit 1) and with (Visit 2) initial instillation of artificial tears. Symptoms were assessed using the Ocular Surface Disease Index (OSDI), Symptom Assessment in Dry Eye questionnaire version two (SANDE II) and Computer Vision Syndrome Questionnaire (CVS-Q). The ocular surface was assessed by measuring corneal higher order aberrations, tear meniscus height (TMH), conjunctival redness, blink rate and incomplete blinking, lipid layer thickness (LLT) and non-invasive keratograph break-up time (NIKBUT).

RESULTS

SANDE II scores were >0 after the computer task in both groups (p ≤ 0.01). SANDE II and CVS-Q scores did not differ between LASIK and controls (p ≥ 0.43). Greater bulbar-temporal conjunctival redness, TMH and LLT and shorter NIKBUT were found after computer use in the LASIK group (p ≤ 0.04), whereas no changes were observed in the controls (p ≥ 0.20). Lower SANDE II and CVS-Q scores were reported at Visit 2 compared with Visit 1 in both groups (p ≤ 0.01). Likewise, no worsening of dry eye signs was observed at Visit 2 (p ≥ 0.11).

CONCLUSIONS

Ocular symptoms reported during computer use were comparable between the groups. However, a worsening of dry eye signs was mostly observed in post-LASIK individuals. The instillation of artificial tears was effective in preventing the effects of computer use on the ocular surface in post-LASIK patients.

Tear Film Dynamics in Visual Display Terminal Users: A Review of Impact on Goblet Cells, Lacrimal and Meibomian Gland Function

PURPOSE

The prevalence of dry eye disease (DED) is rising among visual display terminal (VDT) users, a trend that correlates with the growing use of digital devices. The prevalence of VDT-associated DED is reported based on dry eye questionnaires; however, VDT's impact on tear film parameters is less understood.

METHODS

A review of published literature on both the alterations in tear film observed in VDT users and the impact of various interventions on their tear film.

RESULTS

Most studies show reduction in tear stability as well as reduction in the blink rate. The role of lacrimal gland hypofunction in visual display terminal (VDT) users is a subject of ongoing debate. Schirmer test values typically exceed the 10 mm threshold, suggesting normal tear production, and tear osmolarity remains within normal ranges but VDT users consistently present with lower Schirmer values compared to non-VDT users. The effects on Meibomian glands and mucin levels need more research as the numbers studied are small. Very few studies have analysed mucin levels in VDT users with reports of normal or reduced values. Even asymptomatic users can have tear film instability; hence, the diagnostic criteria need to be formulated and validated. Different interventions such as neurostimulation, blink improving apps, eyelid warming devices, moist goggles, and lubricants have been explored in VDT users but without a control arm and in asymptomatic VDT users in most studies.

CONCLUSION

The alterations have been observed on aqueous, lipid and mucin components of the tear film, although the extent of the impact is variable across studies. There is urgent need of well-designed studies for studying the tear film changes and management options for the upcoming lifestyle epidemic in VDT users.

Potential New Target for Dry Eye Disease-Oxidative Stress

Dry eye disease (DED) is a multifactorial condition affecting the ocular surface. It is characterized by loss of tear film homeostasis and accompanied by ocular symptoms that may potentially result in damage to the ocular surface and even vision loss. Unmodifiable risk factors for DED mainly include aging, hormonal changes, and lifestyle issues such as reduced sleep duration, increased screen exposure, smoking, and ethanol consumption. As its prevalence continues to rise, DED has garnered considerable attention, prompting the exploration of potential new therapeutic targets. Recent studies have found that when the production of ROS exceeds the capacity of the antioxidant defense system on the ocular surface, oxidative stress ensues, leading to cellular apoptosis and further oxidative damage. These events can exacerbate inflammation and cellular stress responses, further increasing ROS levels and promoting a vicious cycle of oxidative stress in DED. Therefore, given the central role of reactive oxygen species in the vicious cycle of inflammation in DED, strategies involving antioxidants have emerged as a novel approach for its treatment. This review aims to enhance our understanding of the intricate relationship between oxidative stress and DED, thereby providing directions to explore innovative therapeutic approaches for this complex ocular disorder.

The effects of breaks on digital eye strain, dry eye and binocular vision: Testing the 20-20-20 rule

PURPOSE

To evaluate the benefits on the eyes of taking breaks based on the 20-20-20 rule.

METHODS

Bespoke computer software using the laptop webcam to assess user breaks, eye gaze and blinking, and emitting personalized reminders of breaks based on the 20-20-20 rule, was downloaded onto the laptops of 29 symptomatic computer users. Digital eye strain (DES), binocular vision and dry eye were assessed before and after two weeks of using the reminders and one week after the discontinuation of the strategy. Binocular measurements included visual acuity, accommodative posture, stereopsis, fixation disparity, ocular alignment, accommodative facility, positive/negative vergences and near point of convergence. Symptoms were evaluated using the computer vision syndrome questionnaire, ocular surface disease index (OSDI), and symptom assessment in dry eye questionnaire (SANDE) versions one and two. Dry eye signs were assessed by measuring tear meniscus height, conjunctival redness, blink rate and incomplete blinking, lipid layer thickness, non-invasive keratograph break-up time, corneal and conjunctival staining and lid wiper epitheliopathy.

RESULTS

A decrease in the duration of computer work and the duration of breaks, along with an increase in the number of breaks taken per day was observed as a result of the 20-20-20 rule reminders (p ≤ 0.015). No changes on any binocular parameter were observed after the management period (p ≥ 0.051), except for an increase in accommodative facility (p = 0.010). Dry eye symptoms and DES decreased with the rule reminders (p ≤ 0.045), although this improvement was not maintained one week after discontinuation (p > 0.05). No changes on any ocular surface and tear film parameter were observed with the rule reminders (p ≥ 0.089).

CONCLUSIONS

The 20-20-20 rule is an effective strategy for reducing DES and dry eye symptoms, although 2 weeks was not enough to considerably improve binocular vision or dry eye signs.

TFOS Lifestyle: Impact of the digital environment on the ocular surface

Eye strain when performing tasks reliant on a digital environment can cause discomfort, affecting productivity and quality of life. Digital eye strain (the preferred terminology) was defined as "the development or exacerbation of recurrent ocular symptoms and/or signs related specifically to digital device screen viewing". Digital eye strain prevalence of up to 97% has been reported, due to no previously agreed definition/diagnostic criteria and limitations of current questionnaires which fail to differentiate such symptoms from those arising from non-digital tasks. Objective signs such as blink rate or critical flicker frequency changes are not 'diagnostic' of digital eye strain nor validated as sensitive. The mechanisms attributed to ocular surface disease exacerbation are mainly reduced blink rate and completeness, partial/uncorrected refractive error and/or underlying binocular vision anomalies, together with the cognitive demand of the task and differences in position, size, brightness and glare compared to an equivalent non-digital task. In general, interventions are not well established; patients experiencing digital eye strain should be provided with a full refractive correction for the appropriate working distances. Improving blinking, optimizing the work environment and encouraging regular breaks may help. Based on current, best evidence, blue-light blocking interventions do not appear to be an effective management strategy. More and larger clinical trials are needed to assess artificial tear effectiveness for relieving digital eye strain, particularly comparing different constituents; a systematic review within the report identified use of secretagogues and warm compress/humidity goggles/ambient humidifiers as promising strategies, along with nutritional supplementation (such as omega-3 fatty acid supplementation and berry extracts).

Influence of Light-EmittingDiode-Derived Blue Light Overexposure on Rat Ocular Surface

We aim to investigate the effect of overexposure to blue light on the rat ocular surface and explore the potential mechanisms. 450 nm light-emitting diode (LED) derived light at 1000 lux was used to irradiate SD rats, 12 hours a day, for consecutive 28 days. Rats in the control group were exposed to 400 lux white light at the same time (in an indoor environment). Tear film breakup time (TBUT), tear volume, and corneal fluorescein staining scores were used to measure the changes to the ocular surface. Expressions of nuclear factor-κB (NF-κB), inhibitor-κB (I-κB), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were measured by real-time PCR, and the activation of the NF-κB pathway was detected by Western blotting, respectively. Cornea ultrastructure was examined by TEM and optical microscope on day 28. Pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB signaling pathway, was used to measure the inhibition of blue light injury. The above indexes were detected again when compared with the solvent-treated group. On day 28, compared with day 0, the TBUT of the blue light group was significantly shorter, and the score was significantly higher. The amount of tear secretion changed slightly with time. HE and PAS staining revealed significantly decreased corneal epithelial cell layers and increased goblet cells after 28-day irradiation of blue light. Disarranged stromal cells, vacuoles in the basal nuclei, and decreased desmosomes were also found in the blue light group. Significantly increased levels of NF-κB, IL-6, TNF-α, and the ratio of phosphorylated NF-κB p65 (pNF-κB p65) to total NF-κB p65 implied blue light-induced damage and pathway activation. In addition, PDTC significantly reduced the phosphorylation of NF-κB activated in blue light-treated corneas and alleviated the ocular surface changes caused by blue light. Finally, our results demonstrated that long-term blue light exposure in rats could cause ocular surface changes and manifest as dry eye. Inflammation and activation of the NF-κB pathway may play a role in the pathogenesis.

Assessment of condition-induced changes on the ocular surface using novel methods to assess the tear film dynamics and the lipid layer

OBJECTIVES

To assess the effects of different condition-induced changes on current and novel ocular surface metrics.

METHODS

Eighty-four healthy volunteers (22.4 ± 2.6 years) participated in this study. The ocular surface and tear film response to (1) computer use, (2) contact lens insertion and (3) tear film instillation during computer use with contact lenses were assessed. Current metrics included the ocular surface disease (OSDI) questionnaire, 5-item dry eye questionnaire (DEQ-5), bulbar redness, tear meniscus height (TMH) and non-invasive keratograph break-up time (NIKBUT). Novel metrics included the lipid layer thickness obtained from the intensity of the reflected Placido disk and the speed of tear film particles post-blink.

RESULTS

Higher dry eye symptoms, TMH and bulbar redness, and lower values in metrics related to the intensity of the Placido disk pattern and to particle speed were found after the computer reading task (p < 0.036). When a contact lens was fitted, lower TMH, NIKBUT and particle speed metrics were obtained (p < 0.044). Mixed ANOVA revealed that artificial tears significantly ameliorated the effect of computer reading on OSDI, DEQ-5, NIKBUT, metrics related to the intensity of the Placido disk pattern and metrics related to particle speed (p < 0.033).

CONCLUSIONS

Computer use and contact lens wear worsened dry eye signs and symptoms, but artificial tears ameliorated this effect. Newly developed methods can serve as a tool to detect changes in the tear film triggered by different ocular surface-disturbing conditions.

Review on the possible pathophysiological mechanisms underlying visual display terminal-associated dry eye disease

BACKGROUND

Visual display terminal (VDT) use is a key risk factor for dry eye disease (DED). Visual display terminal (VDT) use reduces the blink rate and increases the number of incomplete blinks. However, the exact mechanisms causing DED development from VDT use have yet to be clearly described.

PURPOSE

The purpose of the study was to conduct a review on pathophysiological mechanisms promoting VDT-associated DED.

METHODS

A PubMed search of the literature investigating the relationship between dry eye and VDT was performed, and relevance to pathophysiology of DED was evaluated.

FINDINGS

Fifty-five articles met the inclusion criteria. Several pathophysiological mechanisms were examined, and multiple hypotheses were extracted from the articles. Visual display terminal (VDT) use causes DED mainly through impaired blinking patterns. Changes in parasympathetic signalling and increased exposure to blue light, which could disrupt ocular homeostasis, were proposed in some studies but lack sufficient scientific support. Together, these changes may lead to a reduced function of the tear film, lacrimal gland, goblet cells and meibomian glands, all contributing to DED development.

CONCLUSION

Visual display terminal (VDT) use appears to induce DED through both direct and indirect routes. Decreased blink rates and increased incomplete blinks increase the exposed ocular evaporative area and inhibit lipid distribution from meibomian glands. Although not adequately investigated, changes in parasympathetic signalling may impair lacrimal gland and goblet cell function, promoting tear film instability. More studies are needed to better target and improve the treatment and prevention of VDT-associated DED.

Dry Eye-Related Risk Factors for Digital Eye Strain

OBJECTIVES

To evaluate dry eye-related lifestyle and demographic factors associated with digital eye strain (DES).

METHODS

An anonymous online survey was conducted in 851 university students. Participants were classified into DES (computer vision syndrome questionnaire [CVS-Q]≥6) or non-DES (CVS-Q<6). Respondents completed three dry eye questionnaires (Ocular Surface Disease Index [OSDI]; 5-item Dry Eye Questionnaire [DEQ-5]; 8-item Contact Lens Dry Eye Questionnaire) and were surveyed on dry eye risk factors contemplated by the Tear Film and Ocular Surface Society Dry Eye Workshop II.

RESULTS

Six hundred twenty-eight participants were classified into the group with DES and 222 into the group without DES. Participants with DES slept fewer hours, spent more hours indoors with air conditioning, drank more caffeinated beverages, used the computer for longer periods, reported poorer health quality, and obtained a higher score in all questionnaires (P<0.025). A higher proportion of the participants were female, had several health disorders, and took several medications associated with dry eye (P<0.029). Multivariate logistic regression analysis revealed that stress (P=0.035), contact lens wear (P=0.011), hours of computer use per day (P=0.010), migraine headaches (P=0.013), and a higher OSDI (P<0.001) and DEQ-5 score (P<0.001) were associated with DES.

CONCLUSIONS

Several dry eye-related risk factors and health conditions are associated with suffering from DES. Clinicians should acknowledge the relevance of triaging questions and dry eye disease risk factors when dealing with patients who view screens for extended periods.

Determining the Best Management Strategy for Preventing Short-Term Effects of Digital Display Use on Dry Eyes

OBJECTIVES

To assess and compare the effectiveness of four main management strategies for preventing short-term effects of digital display use on dry eye signs and symptoms.

METHODS

The ocular surface, tear film, and visual fatigue of 47 healthy individuals were assessed before and after reading on a laptop computer for 20 min under five different experimental conditions: control, instillation of artificial tears, taking a brief break, using a blue light screen filter, and blink control. Measurements included the Ocular Surface Disease Index (OSDI) Questionnaire, 5-item Dry Eye Questionnaire (DEQ-5), tear meniscus height (TMH), noninvasive keratograph break-up time (NIKBUT), bulbar conjunctival redness, and pupil size.

RESULTS

Worse results were obtained after the control and blue light filter conditions in all variables (P≤0.037). A higher post-task DEQ-5 score (P=0.013) and TMH (P<0.0005) were obtained when taking a brief break compared with pretask, although the increase in symptoms was significantly smaller than that observed in the nonmanagement control condition (P≤0.036). Similarly, a smaller increase in OSDI and DEQ-5 was obtained with the use of artificial tears and blink control in comparison with the control condition (P≤0.008), whereas a greater increase in DEQ-5 and decrease in NIKBUT was obtained for the blue light filter condition in comparison with the instillation of artificial tears (P=0.017) or blink control (P=0.008), respectively. Finally, a significantly lower post-task pupil size was obtained for all the conditions (P≤0.027).

CONCLUSIONS

The instillation of artificial tears and blink control were the best management strategies for preventing short-term effects of digital display use on dry eyes. Conversely, using a blue light filter did not offer any benefits.

The association between visual display terminal use and dry eye: a review

BACKGROUND

Dry eye disease (DED) is a multifactorial disease of the tear film and ocular surface. It causes ocular symptoms, reduced quality of life and a considerable economic burden on society. Prolonged use of visual display terminals (VDTs) has been suggested as an important risk factor for DED.

PURPOSE

This review aims to study the association between DED and VDT use with an emphasis on the prevalence of DED among VDT users and harmful daily duration of VDT use.

METHODS

A PubMed search was conducted and yielded 57 relevant articles based on a set of inclusion and exclusion criteria. The studies were subclassified according to study design.

RESULTS

The far majority of the studies showed an association between VDT use and DED or DED-related signs and symptoms. The prevalence of definite or probable DED in VDT and office workers ranged from 26% to 70%, with as few as 1-2 hr of VDT exposure per day being associated with DED.

CONCLUSION

VDT use is strongly associated with DED. VDT-associated DED is prevalent, but the exact prevalence needs to be further elucidated using standardized DED diagnosis criteria. Furthermore, a safe lower limit of daily VDT use has yet to be established. More research is needed on the effect of digitalization and digital transformation, which are particularly high during the time of the COVID-19 pandemic.

The effect of day-long mask wearing on non-invasive break-up time

Purpose

This study aimed to investigate the effect of day-long face mask wearing on non-invasive tear break-up time (NI-BUT) in health care staff due to working schedules.

Methods

Seventy-four right eyes of 74 participants were included in the study. Participants completed the Ocular Surface Disease Index (OSDI) questionnaire, and NI-BUT measurements were performed between 08.30–09.00 and 16.30–17.00 h. Participants with an initial NI-BUT measurement below 17 s were classified as group-1, and those over 17 s were classified as group-2. NI-BUT changes during the day and correlation to age, gender, and OSDI results were evaluated.

Results

Thirty-eight women and 36 men, with a mean age of 30.9 ± 8.5 years, were included in the study. The mean OSDI score of the participants was 28.6 ± 17.1. NI-BUT means of group-1 at baseline and 8th hour were 11.4 ± 3.3 and 7.9 ± 3.6 s, respectively, and the mean NI-BUT at the 8th hour was statistically significantly lower than the baseline (p < 0.0001). Also, 24.2% (8 people) of those in group-2 had the 8th-hour NI-BUT value fallen into the measurable range (below 17 s). No significant correlation was found between the decrease in NI-BUT value and age, gender, and OSDI (p = 0.08, p = 0.3, and p = 0.2, respectively).

Conclusion

The use of face masks throughout the day leads to a significant reduction in NI-BUT, regardless of age, gender, and OSDI score. Prolonged use of face masks should be considered as a risk factor for evaporative dry eye disease.

Digital display use and contact lens wear: Effects on dry eye signs and symptoms

PURPOSE

To assess the potential additive effects of short-term display use and contact lens (CL) wear on the ocular surface and tear film.

METHODS

Thirty-four healthy volunteers (20.87 ± 2.33 years old) participated in this study. Participants' dry eye symptoms, ocular surface, tear film and pupil size were assessed before and after executing a 20-min reading task on a computer and a smartphone with and without CL wear, or with CL wear and artificial tear instillation. Measurements included the Ocular Surface Disease Index (OSDI) questionnaire; 5-item Dry Eye Questionnaire (DEQ-5); tear meniscus height (TMH); noninvasive keratograph break-up time (NIKBUT); bulbar conjunctival redness (BR) and pupil size.

RESULTS

Higher symptoms were reported after reading on both displays with and without CLs (p ≤ 0.001) for short periods. BR was higher and NIKBUT shorter after reading on the computer regardless of wearing CLs (p ≤ 0.02 and p ≤ 0.02, respectively), while TMH increased for all conditions (p ≤ 0.02) except for CL computer reading (p = 0.23). Reading with CLs did not lead to greater signs of dry eye (BR, NIKBUT) and symptoms compared with reading unaided (p > 0.05), although a smaller increase in TMH was observed when reading on the computer with CLs (p = 0.005). Artificial tear instillation during CL wear led to a smaller increase in symptoms (p ≤ 0.02), a smaller increase in BR (p ≤ 0.04) and a decrease in NIKBUT (p = 0.02) compared to reading without correction.

CONCLUSIONS

Disposable CL wear had no additive effects on signs and symptoms of dry eye when using digital devices for short periods. The instillation of artificial tears is an effective strategy for reducing the impact of display use in CL wearers.

The relationship of distance learning with ocular surface disorders in students in the COVID-19 pandemic

Purpose

To evaluate ocular surface disorders in students whose daily screen time increased due to distance learning during the COVID-19 pandemic.

Methods

Eighty-eight eyes of 44 cases were included in this cross-sectional study. The distance learning students with complaints of redness, stinging, and increased blinking were evaluated. Biomicroscopic examination findings, spherical equivalent, keratometry values, and average daily average screen time were recorded. Ocular Surface Disease Index (OSDI) survey and non-contact tear film breakup time (BUT) assessment (Topcon CA-800) were performed.

Results

Forty-four cases between 15 and 25 years old were evaluated; 25 were girls (56.8%), 19 were boys (43.2%), and the mean age was 19.2 ± 3.9 years (15–25). The mean daily screen time was 4.9 ± 0.9 h. The mean non-contact BUT was 3.18 ± 2.0 s (1.24–8.80 s), and the spherical equivalent was -1.39 ± 1.79. Punctate epitheliopathy was present in 33 eyes (37.5%) on biomicroscopic examination. The mean OSDI score was 37.12 ± 20.30 (10–75) points. A significant positive correlation was present between daily average screen time, punctate epitheliopathy (r = 0,341; p = 0,001), and OSDI score (r = 0,510; p < 0,001). There was also a significant positive correlation between the OSDI score and punctate epitheliopathy (r = 0.754; p < 0.001). There was no significant correlation between the non-contact BUT and punctate epitheliopathy, OSDI score, or daily screen time (p > 0.05).

Conclusion

Ocular surface disorders in students can be associated with increasing daily screen time due to distance learning.

Ocular surface predisposing factors for digital display-induced dry eye

CLINICAL RELEVANCE

The use of digital displays is recognised as a consistent risk factor for dry eye disease.

BACKGROUND

To identify ocular parameters contributing to the impact of computer use on dry eye.

METHODS

The ocular surface of 82 undergraduate students with a mean age of 22.8 ± 2.1 years was assessed at baseline and after reading on a computer for 30 minutes. Measurements included the ocular surface disease index (OSDI) questionnaire, 5-item dry eye questionnaire (DEQ-5), tear meniscus height, non-invasive keratograph break-up time (NIKBUT), conjunctival bulbar redness, meibomian gland dropout percentage, spontaneous blink rate and percentage of incomplete blinks. Multiple linear regressions and generalised linear mixed models were conducted to explore the associations between baseline parameters and pre-task - post-task differences and to predict the impact of computer use, respectively.

RESULTS

Greater dry eye symptoms (p < 0.0005), higher tear meniscus height and conjunctival bulbar redness (p < 0.0005 and p = 0.012, respectively) and shorter NIKBUT (p = 0.03) were obtained after reading on the computer for 30 minutes. The baseline score obtained with the OSDI and DEQ-5 was positively associated with the increase in symptoms with computer use (p < 0.0005), while the change in conjunctival redness and pre-task NIKBUT were associated with the change in NIKBUT (p ≤ 0.005). No ocular surface parameter revealed an association with tear meniscus height changes. Having a positive OSDI score at baseline increased the odds of painful and sore eyes (p = 0.012), while a higher pre-task NIKBUT increased the odds of a reduction in tear stability (p = 0.038).

CONCLUSIONS

Participants with greater dry eye symptoms were more likely to experience a greater increase in symptomatology with computer operation, while the participants with longer NIKBUT and greater conjunctival redness were more likely to suffer a greater reduction in tear stability.

Computer vision syndrome in healthcare workers using video display terminals: an exploration of the risk factors

AIMS

To estimate the prevalence of computer vision syndrome (CVS) in healthcare workers and its relationship to video display terminal (VDT) exposure, sociodemographic, optical correction and work characteristics, and to analyse whether there are differences among occupational groups.

DESIGN

Cross-sectional study.

METHODS

A sample of 1179 physicians and surgeons, nurses, and nursing assistants from two hospitals in Spain between January 2017 and February 2018 were invited to participate in this study. Of these, 622 workers from both hospitals were finally included. CVS was measured using a questionnaire, the CVS-Q^© . Logistic regression was used to identify the factors associated with CVS. All the results were stratified by occupational group.

RESULTS

The prevalence of CVS was 56.75% with nurses being the most affected occupational group (61.75%). It was associated significantly with female sex (aOR = 2.57; 95% CI 1.36-4.88) and morning shifts plus on-call (aOR = 2.33; 95% CI 1.11-4.88) in the physicians and surgeons group. Among the nurses, it was associated with female sex (aOR = 2.35; 95% CI 1.03-5.37), seniority between 10 and 20 years (aOR = 2.17; 95% CI 1.03-4.59), VDT exposure at work of 2-4 h/day (aOR = 6.14; 95% CI 1.08-35.02), VDT exposure at work >4 h/day (aOR = 7.14; 95% CI 1.29-39.62) and self-perception that using the software application was not easy (aOR = 2.49; 95% CI 1.23-5.01).

CONCLUSIONS

A high prevalence of CVS among healthcare workers was observed. The risk factors that increased the likelihood of suffering from this syndrome depended on the occupation.

IMPACT

The findings may be used as a reference for occupational health services to implement specific preventive measures to reduce CVS for each occupational group. Such measures should consider both individual factors and the working conditions.

Practical Guidance for the Use of Loteprednol Etabonate Ophthalmic Suspension 0.25% in the Management of Dry Eye Disease

Dry eye disease (DED) is a prevalent ocular surface disease. Like with any chronic disease, patients with DED can experience episodic flares. There are many existing and upcoming treatments for the chronic treatment of DED, yet treatments for DED flares are limited. Loteprednol etabonate 0.25% is an FDA approved treatment modality for the short-term treatment of the signs and symptoms of DED. This medication is formulated with the customized mucus-penetrating particle (MPP) technology, which has a greater ability to penetrate the ocular surface and more effectively deliver the active steroid to the ocular surface tissues as compared with conventional steroid preparations. There is also increasing utility of loteprednol etabonate 0.25% in the treatment of DED before and/or after cataract or refractive surgery or as induction therapy prior to starting chronic immunomodulatory medication for DED.

Effect of Blue Light Filters on Tear and Contrast Sensitivity in Individuals Using Electronic Devices

OBJECTIVES

To investigate the effect of contact lenses with blue light filters on contrast sensitivity and any alteration in tear quantity and quality.

METHODS

This prospective longitudinal pilot study required three visits by each participant. Monocular visual acuity, contrast sensitivity, phenol red thread test, and tear breakup time were measured at each visit.

RESULTS

There were significant differences in logarithmic contrast sensitivity between the groups. The breakup time (BUT) was significantly lower after using video display terminals than before (P<0.05). No differences in BUT were found between groups video display terminals and contact lenses having the blue filter (P>0.05). However, higher mean values were observed in the group after video display terminal use with contact lenses having the blue filter than that with standard contact lenses (P>0.05 in both groups). Furthermore, the mean value of phenol red thread test on the group after video display terminal use with contact lenses having the blue filter was lower than the group before its use (P>0.05).

CONCLUSION

The results establish a possible relationship between tear stability, improved contrast sensitivity, and the use of a blue filter in contact lenses.

[Digital eye strain. Symptoms, prevalence, pathophysiology, and management]

The digital revolution, which has been underway since the 1980's, is disrupting our daily routines with an exponential increase in the use of screens, which has not been without consequence to our visual system. Digital eye strain (DES), or computer vision syndrome (CVS), includes all the visual symptoms secondary to the use of digital devices. DES is present in at least 50% of regular users of digital media and is defined by blurred vision, difficulty focusing, ocular irritation or burning, dry eye, visual fatigue, headaches and increased sensitivity to light. Exposure time, age, female gender, and work environment are the main factors increasing its prevalence. Its pathophysiology, still poorly understood, is felt to be multifactorial and includes disturbances in the accommodative-convergence balance and changes in the ocular surface. Regarding accommodation and convergence, the studies are mostly old and their results heterogeneous. Conversely, many studies have shown an increase in the prevalence of dry eye in screen users. Although the retinal toxicity of blue light has been proven in in vitro models, the low level of evidence in the available studies does not allow it to be clearly correlated with the symptoms of DES. The objective of this review is to condense the knowledge available in the literature on the symptoms, prevalence, pathophysiology and management of DES.

Online Vs In-person Education: Evaluating the Potential Influence of Teaching Modality on Dry Eye Symptoms and Risk Factors During the COVID-19 Pandemic

OBJECTIVES

To assess the potential effects of switching to online lecture format on dry eye symptoms and dry eye disease (DED) risk factors.

METHODS

An anonymous cross-sectional online survey was conducted in 812 university students (mean age, 21.5±4.0 years). Participants were classified according to the number of hours the participants took online lectures into online students or in-person students. Respondents completed a total of three DED questionnaires (Ocular Surface Disease Index [OSDI]; 5-item Dry Eye Questionnaire; 8-item Contact Lens Dry Eye Questionnaire) and were surveyed on dry eye risk factors contemplated by the Tear Film and Ocular Surface Society Dry Eye Workshop II in addition to other factors potentially linked to dry eye.

RESULTS

Five hundred twenty-three subjects (64.4%) were classified into the online group and 289 (35.6%) into the in-person group. No statistically significant age (P=0.266) or sex (P=0.423) differences were found between groups. Students taking online lectures used the computer more, spent less time outdoors, practised more exercise, wore a face mask for less time, experienced fewer allergies and fewer psoriasis episodes, and obtained a higher OSDI score (P<0.029 for all). Multivariate logistic regression analysis revealed that the hours of online lectures taken per week was independently associated with having a positive OSDI score (P=0.022).

CONCLUSIONS

Taking online lectures is independently associated with having dry eye symptoms. Despite a lower prevalence of DED risk factors, a higher computer use is probably behind the greater ocular dryness reported by online students.

Influence of Reading on Smartphone Screens on Visual Optical Quality Metrics and Tear Film Stability

PURPOSE

To evaluate the impact of a prolonged reading session on a smartphone screen on optical quality metrics and tear film stability.

METHODS

This prospective study was conducted in 41 healthy volunteers who were asked to read an article on a smartphone screen for 20 minutes. The following tests were performed before the reading task in this consecutive order and repeated after the reading task in the same order: automated noninvasive tear break-up time, optical quality assessment including Objective Scatter Index (OSI), modulation transfer function, Strehl ratio, and tear film dynamic analysis as follows: vision break-up time (VBUT) as a function of OSI changes within 20 seconds, using a double-pass aberrometer imaging system, and fluorescein tear break-up time (FBUT) measured using the slit lamp.

RESULTS

All break-up time-related parameters (noninvasive tear break-up time, FBUT and VBUT) were significantly reduced after the reading task (P < 0.01). The OSI was significantly worsened after the reading task (P = 0.01), whereas all the other optical quality metrics (modulation transfer function and Strehl ratio) slightly deteriorated, were not statistically significant. A significant correlation was found between the shortening of the FBUT, VBUT, and the worsening of the OSI (r = -0.33, P < 0.05).

CONCLUSIONS

A reading session on a smartphone screen in healthy subjects was found to significantly affect the tear film stability and objectively worsen the retinal image quality.

Commercially Available Eye Drops Containing Trehalose Protect Against Dry Conditions via Autophagy Induction

Purpose: Evaluation of marketed eye drops with or without trehalose, a nonreducing natural osmoprotector disaccharide, in autophagy modulation and its role in cell survival during desiccation. Materials and Methods: Eye drops containing either sodium hyaluronate (SH) (Hyabak^®, Thea, France) or a combination of SH with trehalose (Thealose Duo^®, Thea, France) were compared with control conditions to evaluate the ability to modulate autophagy in human epithelial cells in vitro. Autophagy was monitored using LC3, a marker of the autophagic machinery, by fluorescence microscopy and immunoblot analysis. Control and autophagy-deficient cells treated with eye drops were exposed to desiccation to mimic dry eyes and cell survival was evaluated by thiazolyl blue tetrazolium bromide (MTT) assay. Trehalose, a known autophagy inducer was used as a positive control. Results: Artificial tears containing SH with and without trehalose induce a complete autophagic flux, as indicated by an increase in the number of autophagosomes and autolysosomes, and the accumulation of the lipidated form of LC3 associated with complete autophagy. In addition, there was a synergistic effect of SH for autophagy induction when combined with trehalose, compared with each of the components alone. Survival of cells treated with both eye drops and exposed to desiccation was decreased in autophagy-deficient cells, demonstrating the essential role of autophagy on eye drop protection. Conclusions: Autophagic flux is induced by SH-containing eye drops, and this phenomenon is enhanced in combination with trehalose. We also demonstrated that autophagy induction is involved in the osmoprotective effects of both trehalose and SH-containing eye drops, to maintain epithelial cell homeostasis in dry conditions.

Computer vision syndrome in presbyopic digital device workers and progressive lens design

PURPOSE

To estimate the prevalence of computer vision syndrome (CVS) in presbyopic digital device workers using two ophthalmic progressive lens designs during the working day, and to analyse the association of CVS with sociodemographic, occupational, digital device exposure and refractive factors.

METHODS

This time series, quasi-experimental design study included 69 presbyopic digital device workers (age range: 46-69 years; mean ± SD = 54.7 ± 5.0). All used desktop computers at their workplace. Progressive addition lenses (PALs) and occupational lenses were used for three months each. CVS was measured with the CVS-Q^© questionnaire before intervention (baseline) and at 1 week, 1 month and 3 months after wearing the lenses. A multivariate logistic regression model was used to identify the factors that were associated with an improved CVS-Q^© score.

RESULTS

37.7% of the subjects were female and 78.3% were ametropes; 65.2% had advanced presbyopia. 56.2% used digital devices at work >6 h day^-1 . The prevalence of CVS at baseline, after wearing PALs for three months and after three months of occupational lens wear was 68.1%, 33.3% and 18.8%, respectively. The mean CVS-Q^© score was lower with occupational lenses than with PALs (p = 0.001). 40.6% of the digital device workers improved their CVS-Q^© score ≥2 points with the occupational lenses. Ametropes were less likely than emmetropes to improve with occupational lenses (OR = 0.27, p = 0.05). 89.8% of the sample workers were satisfied or very satisfied with the occupational lenses and 71% were similarly satisfied with the PALs. 73.9% chose the occupational lenses as their first choice of lens for digital device use, compared with 17.4% for PALs.

CONCLUSIONS

Computer vision syndrome is reduced in presbyopic desktop computer workers wearing occupational lenses compared with PALs, especially in emmetropes.

Accommodative and binocular disorders in preteens with computer vision syndrome: a cross-sectional study

To assess computer vision syndrome (CVS) in a preteen population through an adult-validated CVS questionnaire and to evaluate how digital devices affect accommodative and binocular vision, we enrolled 309 preteens in this cross-sectional study. An adult-validated CVS questionnaire adapted to preteens was used for all subjects. Visual acuity testing, unilateral and alternate cover tests, and tests for accommodative and vergence responses were performed for all preteens. The mean age was 10.75 ± 0.67 (10-12) years. Subjects were divided into two groups: the mild CVS group with a mean CVS score ≤2 and the severe CVS group with a mean CVS score >2. Between the mild and severe CVS groups, statistically significant differences were found in near point of convergence break and recovery (P = 0.03 and P = 0.02, respectively) and distance negative fusional vergence break and recovery (P = 0.02 and P < 0.01, respectively). More children with severe CVS developed vergence disorders than those with mild CVS. Optometric clinical screening assessments could reduce ocular symptomatology and prevent long-term effects. However, poor optometric findings might have occurred first, and the poor convergence skills resulted in the symptoms reported while using devices.

Use of digital displays and ocular surface alterations: A review

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.

Effect of warming eyelids on tear film stability and quality of life in visual display terminal users: a randomized controlled trial

We aimed to evaluate the effect of warming eyelids on tear-film stability and quality of life (QoL) in video display terminal (VDT) users. A prospective study was conducted and 45 volunteers with ocular symptoms and tear-film instability associated with VDT use were randomly allocated into the study (n = 22) or control groups (n = 23). Subjects in the study group used eyelid warming steamer (EWS) for 2 weeks and tear fluorescein breakup time (TBUT) after single and 2-week EWS treatment, Schirmer I test, ocular surface staining scores, meibomian gland assessment, severity of dry eye disease (DED) and QoL scores after 2-week EWS treatment were analysed. The TBUT improved after both single and 2-week EWS treatment (P = 0.023 and 0.027, respectively) in the study group. The ocular surface staining scores were significantly decreased only in the study group (P = 0.038). About 60% DED patients in the study group shifted towards non-DED and the pattern of distribution was significantly different compared to baseline (P < 0.001). The QoL scores significantly improved in the study group (P = 0.002) with a negative correlation with TBUT. In conclusion, in VDT users with short TBUT, eyelid warming steamer is effective in improving tear-film stability and QoL.

Transient tear hyperosmolarity disrupts the neuroimmune homeostasis of the ocular surface and facilitates dry eye onset

Dry eye disease (DED) is a highly prevalent ocular surface disorder with neuroimmune pathophysiology. Tear hyperosmolarity (THO), a frequent finding in affected patients, is considered a key element in DED pathogenesis, yet existing animal models are based on subjecting the ocular surface to the more complex desiccating stress - decreased tear production and/or increased evaporation - instead of strict hyperosmolar stress. Here we characterized a murine model of THO that does not involve desiccating stress, thus allowing us to dissect the contribution of THO to DED. Our results showed that THO is sufficient to disrupt neuroimmune homeostasis of the ocular surface in mice, and thus reproduce many sub-clinical DED findings. THO activated nuclear factor-κB signalling in conjunctival epithelial cells and increased dendritic cell recruitment and maturation, leading to more activated (CD69+ ) and memory (CD62lo CD44hi) CD4+ T-cells in the eye-draining lymph nodes. Ultimately, THO impaired the development of ocular mucosal tolerance to a topical surrogate antigen in a chain of events that included epithelial nuclear factor-κB signalling and activation of transient receptor potential vanilloid 1 as the probable hypertonicity sensor. Also, THO reduced the density of corneal intraepithelial nerves and terminals, and sensitized the ocular surface to hypertonicity. Finally, the adoptive transfer of T-cells from THO mice to naïve recipients under mild desiccating stress favoured DED development, showing that THO is enough to trigger an actual pathogenic T-cell response. Our results altogether demonstrate that THO is a critical initiating factor in DED development.

Investigation of Dry Eye Symptoms in Lecturers by Ocular Surface Disease Index

Objectives:

The aim of this study was to evaluate the prevalence of dry eye symptoms among lecturers.

Materials and Methods:

The study included 254 lecturers employed at Mersin University. The lecturers were selected by simple random sampling from lists obtained from the personnel department. Data were obtained between November 15 and December 15, 2017 using a questionnaire developed by the researchers and the Ocular Surface Disease Index (OSDI). The data were evaluated using descriptive statistics, Student’s t test, ANOVA, and correlation tests with the SPSS package program.

Results:

Of the lecturers who participated in the study, 52.8% were male and 47.2% were female, and the mean age was 39.29±9.41 years. According to OSDI scores, 20.5% of the participants had mild, 15% had moderate, and 36.5% had severe disease. There were significant differences in mean OSDI score based on sex (p<0.001), alcohol use (p=0.01), continuous drug use (p=0.03), wearing glasses (p=0.04), history of dry eye (p<0.001), and presence of dry eye symptoms (p<0.001). There were also significant differences between the OSDI score categories in terms of sex (p<0.001), smoking status (p=0.04), wearing glasses (p=0.03), history of dry eye (p<0.001), and presence of dry eye symptoms. The only factor significantly correlated with OSDI score was daily duration of computer usage (p=0.009).

Conclusion:

Our study showed that a substantial proportion of lecturers experience dry eye symptoms, and OSDI scores were associated with daily duration of computer use. Determining the factors associated with dry eye is important for the planning of preventive interventions.

Prediction of Computer Vision Syndrome in Health Personnel by Means of Genetic Algorithms and Binary Regression Trees

One of the major consequences of the digital revolution has been the increase in the use of electronic devices in health services. Despite their remarkable advantages, though, the use of computers and other visual display terminals for a prolonged time may have negative effects on vision, leading to a greater risk of Computer Vision Syndrome (CVS) among their users. In this study, the importance of ocular and visual symptoms related to CVS was evaluated, and the factors associated with CVS were studied, with the help of an algorithm based on regression trees and genetic algorithms. The performance of this proposed model was also tested to check its ability to predict how prone a worker is to suffering from CVS. The findings of the present research confirm a high prevalence of CVS in healthcare workers, and associate CVS with a longer duration of occupation and higher daily computer usage.

Blue light exposure in vitro causes toxicity to trigeminal neurons and glia through increased superoxide and hydrogen peroxide generation

Today the noxiousness of blue light from natural and particularly artificial (fluorescent tubes, LED panels, visual displays) sources is actively discussed in the context of various ocular diseases. Many of them have an important neurologic component and are associated with ocular pain. This neuropathic signal is provided by nociceptive neurons from trigeminal ganglia. However, the phototoxicity of blue light on trigeminal neurons has not been explored so far. The aim of the present in vitro study was to investigate the cytotoxic impact of various wavebands of visible light (410-630 nm) on primary cell culture of mouse trigeminal neural and glial cells. Three-hour exposure to narrow wavebands of blue light centered at 410, 440 and 480 nm of average 1.1 mW/cm² irradiance provoked cell death, altered cell morphology and induced oxidative stress and inflammation. These effects were not observed for other tested visible wavebands. We observed that neurons and glial cells processed the light signal in different manner, in terms of resulting superoxide and hydrogen peroxide generation, inflammatory biomarkers expression and phototoxic mitochondrial damage. We analyzed the pathways of photic signal reception, and we proposed that, in trigeminal cells, in addition to widely known mitochondria-mediated light absorption, light could be received by means of non-visual opsins, melanopsin (opn4) and neuropsin (opn5). We also investigated the mechanisms underlying the observed phototoxicity, further suggesting an important role of the endoplasmic reticulum in neuronal transmission of blue-light-toxic message. Taken together, our results give some insight into circuit of tangled pain and photosensitivity frequently observed in patients consulting for these ocular symptoms.

The Healthy e-Elderly People Assessment (HEPA) application

Purpose

The purpose of this paper is to evaluate health effects and determine the factors associated with health effects from smartphone and tablet use among the elderly in Thailand.

Design/methodology/approach

This study was a cross-sectional descriptive study. The participants comprised 490 elderly people. A self-administered questionnaire was used for data collection via the Healthy e-Elderly People Assessment mobile application in the Android operating system by Google which consists of five parts of a questionnaire. The variables were analyzed using SPSS such as frequency, percentage, mean and binary logistic regression.

Findings

Altogether, the participants were 223 males and 267 females; mean age=64.9±5.4. The average time spent using a mobile device was 2.8±1.9 h/day. Participants recorded that after use of either device, 59.0 percent experienced eye pain, 52.7 percent experienced dim eyes, 30.2 percent experienced tiredness, and 28.0 percent experienced moodiness. Socially, 26.8 percent recorded changes in social interaction. Periods of time using devices, time consumed in device usage (hours/day), the type of application, and the difference in times of use, place of usage and time spent in rest breaks from smartphone or tablet usage were significantly associated with health effects (p<0.05).

Originality/value

The elderly users may be at risk of several health effects from smartphone and tablet use. The potential gap in knowledge conceals some of the risk factors for the current health effects. Practical intervention to reduce health effects from the use of smartphones and tablets should be considered.

Blue light phototoxicity toward human corneal and conjunctival epithelial cells in basal and hyperosmolar conditions

AIMS

The ocular surface is the very first barrier between the visual system and external environment. It protects the eye from the exposure to various light sources that significantly emit in blue spectrum. However, the impact of blue light on the ocular surface has been poorly explored so far. In this study, we investigated in vitro the phototoxicity of blue light illumination in human epithelial cells of the ocular surface. We worked either in basal conditions or under hyperosmolar stress, in order to mimic dry eye disease (DED) that is the most common disease involving the ocular surface.

RESULTS

Corneal and conjunctival epithelial cells suffered the most from violet-blue light but also from longer-wave blue light. Exposure to blue wavebands significantly decreased cellular viability, impacted on cellular morphology and provoked reactive oxygen species (ROS) over-production. Conjunctival epithelial cell line had a greater photosensitivity than the corneal epithelial one. Hyperosmolar stress potentiated the blue light phototoxicity, increasing inflammation, altering mitochondrial membrane potential, and triggering the glutathione-based antioxidant system.

INNOVATION

In human epithelial corneal and conjunctival cells of the ocular surface, we demonstrated the harmful impact of blue light on viability, redox state and inflammation processes, which was modified by hyperosmolarity.

CONCLUSION

Blue light induced cell death and significant ROS production, and altered the expression of inflammatory genes and operation of the cellular defensive system. We established for the first time that hyperosmolar stress impacted phototoxicity, further suggesting that DED patients might be more sensitive to blue light ocular toxicity.

Variability of Tear Osmolarity Measurements With a Point-of-Care System in Healthy Subjects-Systematic Review

PURPOSE

To assess the variability of osmolarity measured by the point-of-care TearLab system in healthy eyes.

METHODS

A systematic review was performed by searching MEDLINE, Scopus, and the Web of Science Databases until November 2016 and checking reference lists of included articles and reviews. The requirements for inclusion were the availability of TearLab results in healthy subjects and a minimum study sample of 20 eyes. Two reviewers assessed articles against the inclusion criteria, extracted relevant data, and examined the methodological quality. We computed the weighted mean osmolarity using the study size as the weighting factor and calculated the rate of subjects with osmolarity values >308 mOsm/L, the Dry Eye Workshop Report 2017 (DEWS) cut-off value for dry eye disease (DED). We repeated the analysis after excluding reports with a possible conflict of interest or missing description of subject selection.

RESULTS

Searches retrieved 105 nonduplicate articles, and we included 33 studies investigating 1362 eyes of healthy participants who were asymptomatic and showed no clinical signs of DED. Sixty-three percent were female, and mean age was 37.3 years (range: 21.5-69.0 yr). Weighted mean osmolarity was 298 mOsm/L (95% confidence interval, 282-321 mOsm/L). The result of the subgroup analysis was similar. Overall, 386 of 1362 eyes (28.3%) fulfilled the DEWS's definition of DED (>308 mOsm/L).

CONCLUSIONS

There is a high variability of osmolarity measurements with the TearLab system. A substantial number of healthy subjects fulfill the DEWS's definition of DED. We propose interpreting the TearLab osmolarity results cautiously and in the context of other established methods.

Use of the Controlled Adverse Environment (CAE) in Clinical Research: A Review

The many internal and external factors that contribute to the pathophysiology of dry eye disease (DED) create a difficult milieu for its study and complicate its clinical diagnosis and treatment. The controlled adverse environment (CAE^®) model has been developed to minimize the variability that arises from exogenous factors and to exacerbate the signs and symptoms of DED by stressing the ocular surface in a safe, standardized, controlled, and reproducible manner. By integrating sensitive, specific, and clinically relevant endpoints, the CAE has proven to be a unique and adaptable model for both identifying study-specific patient populations with modifiable signs and symptoms, and for tailoring the evaluation of interventions in clinical research studies.

TFOS DEWS II Tear Film Report

The members of the Tear Film Subcommittee reviewed the role of the tear film in dry eye disease (DED). The Subcommittee reviewed biophysical and biochemical aspects of tears and how these change in DED. Clinically, DED is characterized by loss of tear volume, more rapid breakup of the tear film and increased evaporation of tears from the ocular surface. The tear film is composed of many substances including lipids, proteins, mucins and electrolytes. All of these contribute to the integrity of the tear film but exactly how they interact is still an area of active research. Tear film osmolarity increases in DED. Changes to other components such as proteins and mucins can be used as biomarkers for DED. The Subcommittee recommended areas for future research to advance our understanding of the tear film and how this changes with DED. The final report was written after review by all Subcommittee members and the entire TFOS DEWS II membership.

Prevalence of ocular surface disease symptoms and risk factors in group of university students in Monterrey, Mexico

Background

The objective of this study was to determine the prevalence of symptoms of ocular surface disease and its relationship with associated risk factors in students from the University of Monterrey using Ocular Surface Disease (OSDI) questionnaire.

Methods

A cross-sectional survey was conducted between October and December 2014 to assess the prevalence and risk factors for ocular surface disease in a group of students from Universidad de Monterrey in Monterrey, Mexico. The severity of the disease was measured via the Ocular Surface Disease Index (OSDI) questionnaire.

Results

The OSDI average value was 26.85 ± 20.79 points, with 70.4% of students (579) had OSDI score higher than 12 points. Women had ocular surface disease 1.63 times more than men (OR 1.29, 95% CI 1.13,1.48). Students who used ophthalmic drops have an OR 2.00 (95% CI 1.65,2.40), and students who smoke have an OR 1.24 (95% CI 1.06,1.46). Use of contact lenses, hours in front of computer or history of refractive surgery has low-estimated effect on the probability of presenting an ocular disease.

Conclusions

University students have a prevalence of 70.4% of ocular surface disease (OSD). OSD was associated with gender (women have a higher prevalence), smoking and the use of eye drops. A program to modify these risk factors to reduce the prevalence is needed.

Prevalence of dry eye disease in visual display terminal workers: a systematic review and meta-analysis

OBJECTIVE

To evaluate the prevalence and risk factors of dry eye disease (DED) in workers using visual display terminals (VDT).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

We searched PubMed, Cochrane Library, Embase and Science Direct databases for studies reporting DED prevalence in VDT workers.

RESULTS

16 of the 9049 identified studies were included, with a total of 11,365 VDT workers. Despite a global DED prevalence of 49.5% (95% CI 47.5 to 50.6), ranging from 9.5% to 87.5%, important heterogeneity (I(2)=98.8%, p<0.0001) was observed. Variable diagnosis criteria used within studies were: questionnaires on symptoms, tear film anomalies and corneoconjunctival epithelial damage. Some studies combined criteria to define DED. Heterogeneous prevalence was associated with stratifications on symptoms (I(2)=98.7%, p<0.0001), tears (I(2)=98.5%, p<0.0001) and epithelial damage (I(2)=96.0%, p<0.0001). Stratification of studies with two criteria adjusted the prevalence to 54.0% (95% CI 52.1 to 55.9), whereas studies using three criteria resulted in a prevalence of 11.6% (95% CI 10.5 to 12.9). According to the literature, prevalence of DED was more frequent in females than in males and increased with age.

CONCLUSIONS

Owing to the disparity of the diagnosis criteria studied to define DED, the global prevalence of 49.5% lacked reliability because of the important heterogeneity. We highlight the necessity of implementing common DED diagnostic criteria to allow a more reliable estimation in order to develop the appropriate preventive occupational actions.