Effect of Simulated and Real Aircraft Cabin Environments on Tear Film Parameters in Dry Eye Disease: A Meta-Analysis

Understanding the Dual Dilemma of Dry Eye and Glaucoma: An International Review.

To investigate the efficacy of umbilical cord serum eyedrops after laser epithelial keratomileusis (LASEK). Sixty patients (120 eyes) with myopia who underwent LASEK were studied. Thirty-two patients (64 eyes) were treated with 20% umbilical cord serum eyedrops in combination with conventional treatment (group A), and 28 patients (56 eyes) received conventional treatment only (group B). Epithelial healing time was analysed. Visual acuity, refraction, haze score (0-4) and tear film and ocular surface parameters were evaluated at 1, 2, 4 and 12 weeks after LASEK. The concentration of transforming growth factor (TGF)-β1 in tears was measured with ELISA at 1 week after LASEK. No significant differences in visual acuity and refraction were found between groups. The mean time to epithelial healing was 3.53 ± 1.19 days in group A and 3.91 ± 1.41 days in group B (p = 0.18). The mean haze scores at 2 and 4 weeks were 0.59 ± 0.80 and 0.31 ± 0.54 in group A and 1.06 ± 0.91 (p = 0.02) and 0.69 ± 0.78 (p = 0.03) in group B. Four and 12 weeks after LASEK, tear film break-up time was longer and keratoepitheliopathy score was lower in group A compared with group B. The mean concentration of TGF-β1 was lower in group A compared with group B (p = 0.01). Application of 20% umbilical cord serum eyedrops in addition to conventional treatment after LASEK can reduce early postoperative corneal haze and improve tear film and ocular surface parameters.

To describe dry eye disease in French elderly subjects. The Alienor Study is a population-based study on age-related eye disease in 963 residents of Bordeaux (France), aged 73 years or more. Self-reported dry eye disease and use of artificial tears were documented through face-to-face interview. Dry eye symptoms were assessed using the Ocular Surface Disease Index (OSDI) questionnaire and tear film stability by tear break-up time measurements (TBUT). Definite dry eye disease was defined as self-reported dry eye, confirmed by use of artificial tears and/or OSDI greater or equal to 22. Nine hundred and fifteen subjects, with mean age of 80 ± 4 years, returned the OSDI questionnaire. Of these, 271 (29.6%) subjects reported a dry eye disease and 135 (14.7%) were using artificial tears. An OSDI score > 22 was found in 359 (39.2%) subjects and a TBUT < 5 seconds in 335/746 (44.9%) subjects. Overall, definite dry eye affected 21.9% of subjects and was more frequent in women (27.1%) than in men (13.6%). After multivariate adjustment, dry eye disease was also significantly less frequent in subjects with high educational level (odds ratio (OR) = 0.49, 95% confidence interval (CI): 0.31-0.78 for long secondary school) and more frequent in subjects with ocular hypertension (OR = 1.61, 95% CI: 1.02-2.57) and those using anxiolytics (OR = 1.53, 95% CI: 1.02-2.29). This large observational study confirmed the high prevalence of dry eye symptoms among elderly subjects and confirmed some of the previously identified risk factors (in particular female gender and use of anxiolytics).

Aim: to study the changes in the critical parameters of tear film stability and autorefractometry in patients with mild dry eye syndrome (DES) after instilling artificial tear products of different viscosity. Patients and Methods: thirty patients aged 23–70 with mild bilateral DES were examined using the Visionix VX120+Dry Eye multi-diagnostic unit equipped with the TF-Scan to fix and assess tear film stability and tear breakup time (TBUT). The critical refraction and tear film parameters were evaluated by keratometry, corneal topography, TBUT, and tear meniscus height measurements. Next, an artificial tear product was instilled, i.e., group 1 (14 patients, 28 eyes) received a 0.15% sodium hyaluronate-based preparation, and group 2 (16 patients, 32 eyes) received a 0.4% sodium hyaluronate-based preparation. The examination was repeated after 30 sec and 5 min. Controls were seven healthy individuals (14 eyes). Results: in DES, breaks in the tear film appeared earlier and affected greater corneal surface area. A "Destabilized tear film area" parameter of the Visionix VX120+Dry Eye contributed significantly to the knowledge of tear film functionality, thereby empowering the diagnostic armamentarium in DES. As early as 30 sec after instillation of both artificial tear preparations, breakup-free time tended to increase, while the area of tear film destabilization tended to reduce. After 5 min, this trend continued to increase, particularly after instilling 0.15% sodium hyaluronate-based preparation. At the same time, changes in keratometry readings (i.e., sphere and cylinder) and astigmatism axis orientation were reported. Corneal refractive power (more in the flattest axis) increased, in particular, after the instillations of 0.15% hyaluronic acid. The range of changes was 0.00–0.75 D for the sphere power, 0.00–0.50 D for the cylinder power, and 0–69 degrees for astigmatism axis orientation. Conclusions: our findings with the Visionix VX120+Dry Eye multi-diagnostic unit demonstrate a significant variation of autorefractometry readings in DES depending on the extent of ocular surface hydration. These phenomena raise questions about the accuracy of autorefractometry readings. Therefore, autorefractometry should be performed after normalizing tear film volume and stability. Keywords: dry eye syndrome, Visionix®, autorefractometry, tearscopy, the effect of artificial tears on results. For citation: Brzheskiy V.V., Efimova E.L., Kopylova M.A. et al. Changes in the functionality of tear film and autorefractometry reading after instillations of artificial tear products of different viscosity. Russian Journal of Clinical Ophthalmology. 2021;21(4):200–204 (in Russ.). DOI: 10.32364/2311-7729-2021-21-4-200-204.

Clinical Relevance: With the growing concern of excessive screen use during pandemic era, there is an increasing need to determine the effect of smartphone use on intraocular pressure (IOP) and ocular surface in healthy adults for future targeted preventive measures. Purpose: To investigate the effect of smartphone usage in terms of IOP and evaporative dry eye changes at the different lighting conditions. Methods: A prospective comparative study involving 112 eyes of 56 healthy adults (age &lt;40 years) was conducted in a suburban community. The participants were requested to watch preselected videos on the smartphone (Google PIXEL 2XL) for 20 min, under standardized bright room and dim room conditions on different examination days. Three sets of IOP examinations were performed each day using the Goldmann Applanation tonometer: pre-work, during smartphone work [10 min], and immediately post-work [20 min]. Tear break up time (TBUT) was recorded before every IOP measurement. Results: Under the bright light, the mean pre-work IOP was 13.3 ± 1.9 mmHg, and after 10 min of work, the mean IOP increased to 14.0 ± 2.3 mmHg. When the smartphone use lasted for 20 min, the IOP showed a further significant increase (14.4 ± 2.4 mmHg; P &lt; 0.001). Under the dim-light condition, the mean IOP significantly increased after 10 min (from 13.6 ± 1.9 to 14.1 ± 2.0 mmHg) and further increased to 15.0 ± 2.2 mmHg ( P &lt; 0.001) at 20 min. The percentage of IOP rise is significantly higher in dim light conditions than in bright light (mean difference = 3.1%, P = 0.011). The mean TBUT significantly declined over the 20 min in both bright and dim light (from 8.1 to 4.0 seconds from 7.0 to 3.5 sec respectively; P &lt; 0.001). Conclusion: In healthy adults, smartphone usage for 20 min induced a small but significant elevation in IOP, which is still within the physiological fluctuation range. IOP rise and reduced tear film stability is more prominent under dim light conditions.

To evaluate the efficacy and safety of new moist cool air device (MCAD) for ocular symptoms, tear film stability and ocular surface status in office workers with dry eye disease (DED). In this prospective single-centre clinical trial, 40 eyes of 20 patients with DED were recruited and randomly divided into two groups (group with MCAD exposure and group without MCAD). All subjects are visual display terminals (VDTs) workers spending at least 4 h/day in front of VDTs. Patients using MCAD underwent moist air applications for 4 h/day for a total of five working weekdays during VDT works at their offices. The other group of patients performed their VDT work without moist cool air device exposure. The change in symptoms of ocular surface (OS) dryness, fatigue and discomfort was evaluated using visual analogue scale (VAS) scores. Changes in visual function, tear functions and ocular surface status were evaluated using best-corrected visual acuity (BCVA), the functional visual acuity (FVA) test, blink rate, BUT measurements, strip meniscometry (SM), tear evaporation rate, fluorescein staining and rose bengal staining scores. Tear film lipid layer interferometry was also performed to assess the status of the lipid layer over the tear film. In addition, adverse events were recorded. In group with MCAD, symptoms of OS dryness during VDTs work, and FVA and BUT were significantly improved. SM and tear evaporation rate were significantly improved. There were no statistically significant differences on lipid layer stability and corneal staining scores in both groups. Blink rate was significantly increased in group without MCAD. No adverse events were reported during this trial. Moist cool air device use provided symptomatic relief of ocular dryness and improvement on tear stability in office workers with DED. This new device seems to be a safe and promising alternative in the treatment of DED.

Introduction: Vision is one of the primary sensory systems involved in performing sports skills. Exercise is essential for preventing and managing numerous chronic eye-related conditions. This study aimed to investigate the effects of three types of exhaustive exercise activities on intraocular pressure (IOP) and tear film stability in patients with dry eye disease (DED). Methods: Twenty-two healthy female participants took part in this study. The participants randomly performed three types of exhaustive physical activities—swimming, resistance training, and running—on separate days, with a maximum interval of four days between consecutive tests. Intraocular pressure (IOP) and tear break-up time (TBUT) were measured before and immediately after each activity. The shuttle run test was used to assess aerobic activity. Repeated-measures analysis of variance (ANOVA) was employed to compare variables across the three conditions (aerobic, resistance, and swimming), and the Bonferroni post-hoc test was used when significant differences were found. The significance level was set at P&lt;0.05. Results: Significant changes in intraocular pressure (IOP) were observed post-exercise (P=0.001): Resistance training increased IOP from 16.12±2.44 to 19.44±3.28 mmHg (change:+20.6%), while swimming decreased it to 13.12±2.57 mmHg (change: -18.6%) and running to 13.32±2.05 mmHg (change: -17.4%). TBUT changes were non-significant (P≥0.05): resistance 3.72±1.18 seconds; change: -19.1%), swimming (3.60±0.89 seconds; change: -21.7%), and running (3.64±1.38 seconds; change: -20.9%). Conclusion: Based on the findings, resistance training is associated with an increase in IOP, while aerobic exercises and swimming result in a decrease in IOP. Additionally, tear film stability (TBUT) showed a slight reduction after all three activities, though no significant differences were observed between the groups.

Despite the widespread use of topical CsA to treat dry eye, we found that evidence on the effect of CsA on ocular discomfort and ocular surface and tear film parameters such as corneal fluorescein staining, Schirmer's test, and TBUT is inconsistent and sometimes may not be different from vehicle or artificial tears for the time periods reported in the trials. There may be an increase in non-serious, treatment-related adverse effects (particularly burning) in the CsA group. Topical CsA may increase the number of conjunctival goblet cells. However, current evidence does not support that improvements in conjunctival mucus production (through increased conjunctival goblet cells) translate to improved symptoms or ocular surface and tear film parameters. All published trials were short term and did not assess whether CsA has longer-term disease-modifying effects. Well-planned, long-term, large clinical trials are needed to better assess CsA on long-term dry eye-modifying effects. A core outcome set, which ideally includes both biomarkers and patient-reported outcomes in the field of dry eye, is needed.

Effects of Prolonged Reading on Dry Eye

Exploring topical anti-glaucoma medication effects on the ocular surface in the context of the current understanding of dry eye

Botulinum toxin-A (BoNT-A) injections have become increasingly popular for cosmetic treatments in the upper face region, particularly for reducing wrinkles and achieving aesthetic improvements. While the cosmetic benefits are well-documented, the potential effects of these injections on ocular surface health and tear film dynamics remain incompletely understood. This study aimed to comprehensively investigate the impact of BoNT-A injections on tear film parameters and ocular surface health across different time intervals following treatment. This cross-sectional study evaluated 80 participants divided into four groups of 20 each. Three groups consisted of patients who had received upper face BoNT-A injections within the previous six months, evaluated at different time intervals: group 1 (0-1 month post-injection), group 2 (1-3 months post-injection), and group 3 (3-6 months post-injection). The fourth group served as an age- and gender-matched control group with no history of BoNT-A treatment. A comprehensive assessment of ocular surface health was conducted using three standardized parameters: the Schirmer test (without anesthesia) for tear production, the tear break-up time (TBUT) for tear film stability, and the Ocular Surface Disease Index (OSDI) for symptom evaluation. All participants underwent standardized BoNT-A injection protocols, receiving a total of 50 units administered by the same experienced cosmetic surgeon. Significant differences in tear production were observed, with the 0-1 month post-injection group exhibiting the highest mean Schirmer score (18.35±7.63 mm), compared to 12.9±3.64 mm in the control group (p<0.01). TBUT measurements revealed greater tear film stability in the control (11.35±2.92 seconds) and 0-1 month (11.05±2.97 seconds) groups compared to the 1-3 and 3-6 month groups (p<0.05). OSDI scores indicated increased symptom severity in the 1-3 month (18.62±7.04) and 3-6 month (18.82±6.08) post-injection groups compared to the control group (11.82±2.67) (p<0.001). Cosmetic BoNT-A injections can lead to alterations in tear film dynamics and ocular surface health, with effects varying across different post-injection time periods. The findings suggest an initial increase in tear production followed by potential alterations in tear film stability and increased dry eye symptoms in the months following treatment. These effects appear to vary over time following injection. Further research is now needed to fully elucidate the long-term impact of cosmetic BoNT-A injections on the ocular surface.

We identified 22 RCTs conducted in the USA, Italy, Spain, China, South Korea, and India. These RCTs reported outcome data from a total of 4169 participants with DED. Study characteristics and risk of bias All trials recruited adults aged 18 years or older, except one trial that enrolled children and adolescents aged between 3 and 14 years. Half of these trials involved predominantly female participants (median 79%, interquartile range [IQR] 76% to 80%). On average, each trial enrolled 86 participants (IQR 40 to 158). The treatment duration of topical steroids ranged between one week and three months; trial duration lasted between one week and six months. Eight trials were sponsored exclusively by industry, and four trials were co-sponsored by industry and institutional or governmental funds. We assessed the risk of bias of both subjective and objective outcomes using RoB 2, finding nearly half of the trials to be at high risk of bias associated with selective outcome reporting. Findings Of the 22 trials, 16 evaluated effects of topical steroids, alone or in combination with tobramycin, as compared with lubricants (AT, vehicle), AT plus tobramycin, or no treatment. Corticosteroids probably have a small to moderate effect on improving patient-reported symptoms by 0.29 standardized mean difference (SMD) (95% confidence interval [CI] 0.16 to 0.42) as compared with lubricants (moderate certainty evidence). Topical steroids also likely have a small to moderate effect on lowering corneal staining scores by 0.4 SMDs (95% CI 0.18 to 0.62) (moderate certainty evidence). However, steroids may increase tear film break-up time (TBUT) slightly (mean difference [MD] 0.70 s, 95% CI 0.06 to 1.34; low certainty evidence) but not tear osmolarity (MD 1.60 mOsm/kg, 95% CI -10.47 to 13.67; very low certainty evidence). Six trials examined topical steroids, either alone or in combination with CsA, against CsA alone. Low certainty evidence indicates that steroid-based interventions may have a small to moderate effect on improving participants' symptoms (SMD -0.33, 95% CI -0.51 to -0.15), but little to no effect on corneal staining scores (SMD 0.05, 95% CI -0.25 to 0.35) as compared with CsA. The effect of topical steroids compared to CsA alone on TBUT (MD 0.37 s, 95% CI -0.13 to 0.87) or tear osmolarity (MD 5.80 mOsm/kg, 95% CI -0.94 to 12.54; loteprednol etabonate alone) is uncertain because the certainty of the evidence is low or very low. None of the included trials reported on quality of life scores. Adverse effects The evidence for adverse ocular effects of topical corticosteroids is very uncertain. Topical corticosteroids may increase participants' risk of intraocular pressure (IOP) elevation (risk ratio [RR] 5.96, 95% CI 1.30 to 27.38) as compared with lubricants. However, when compared with CsA, steroids alone or combined with CsA may decrease or increase IOP elevation (RR 1.45, 95% CI 0.25 to 8.33). It is also uncertain whether topical steroids may increase risk of cataract formation when compared with lubricants (RR 0.34, 95% CI 0.01 to 8.22), given the short-term use and study duration (four weeks or less) to observe longer-term adverse effects. AUTHORS' CONCLUSIONS: Overall, the evidence for the specified review outcomes was of moderate to very low certainty, mostly due to high risk of bias associated with selective results reporting. For dry eye patients whose symptoms require anti-inflammatory control, topical corticosteroids probably provide small to moderate degrees of symptom relief beyond lubricants, and may provide small to moderate degrees of symptom relief beyond CsA. However, the current evidence is less certain about the effects of steroids on improved tear film quality or quantity. The available evidence is also very uncertain regarding the adverse effects of topical corticosteroids on IOP elevation or cataract formation or progression. Future trials should generate high certainty evidence to inform physicians and patients of the optimal treatment strategies with topical corticosteroids in terms of regimen (types, formulations, dosages), duration, and its time-dependent adverse profile.

How effective and safe are punctal plugs in treating dry eye disease? A systematic review and meta-analysis.

Purpose:To describe the pattern of intraocular pressure (IOP) changes after squint surgery in eyes of black Africans at the University College Hospital, Ibadan, Nigeria.Materials and Methods:This was a retrospective review of the clinical records of patients who underwent squint surgery between 2010 and 2019. Data on demographic characteristics, preoperative and postoperative intraocular pressure values, co-existing ocular pathology, type of strabismus, surgery performed, frequency and duration of postoperative topical steroid use and treatment received for elevated intraocular pressure were collected and descriptively summarised.Results:Thirty-six (39.1%) out of 92 patients who had squint surgery during the study period met study inclusion criteria. Mean age was 20.5 ± 13.6 years. All patients were administered Maxitrol® ointment postoperatively. Baseline, peak and net change in IOP were 12.9 ± 2.6 mmHg, 21.3 ± 6.8 mmHg and 8.39 ± 7.2 mmHg respectively. Thirty-one (86.1%) patients had elevation in IOP from baseline; 21 (67.7%) of these had significant IOP elevation. Topical steroid therapy was tailed off rapidly for all patients with significant IOP elevation. Twelve patients were commenced on topical IOP lowering medications, with normalization of intraocular pressure in majority of them by three months after surgery.Conclusion:Elevated intraocular pressure with the use of topical dexamethasone ointment after squint surgery was common in this study and majority of the patients had significant elevation in intraocular pressure. Close monitoring of the intraocular pressure of black patients, especially children, on topical steroid medication after squint surgery is strongly recommended.

Spatial Correlation of Speckle Fluctuations Reveals Thickness and Features of the Ocular Surface Tear Film