Effect of chlorhexidine, povidone-iodine and betadine antiseptic eye drops on cultured human conjunctival goblet cell survival.

PURPOSE: To compare the effect of the ocular antiseptic treatments 0.05% chlorhexidine, 5% povidone-iodine (PI) and 5% betadine on cell viability and mucin secretion of primary cultured human goblet cells (GCs). METHOD: GC viability was analysed using lactate dehydrogenase (LDH) and tetrazolium dye (MTT) colorimetric assays. Expression of mucin was visualised by immunohistochemical MUC5AC staining. RESULTS: PI and betadine significantly reduced GC survival compared to the control (mean cell survival 23 ± 6% and 23 ± 7%, respectively, p < 0.05), whereas chlorhexidine did not significantly affect GC viability (mean cell survival: 78 ± 17%), as measured by the LDH assay. Similar results were obtained from the MTT assay, where PI and betadine caused a significant loss of GCs (mean cell survival: 26 ± 12% and 26 ± 13%, respectively, p < 0.05). Chlorhexidine did not significantly alter GC survival compared to the control (mean cell survival: 79 ± 8%). PI and betadine caused a dispersion of mucin secretion, which chlorhexidine did not. CONCLUSION: The most used antiseptic treatments, PI and betadine, applied prior to ocular surgery are significantly more cytotoxic to conjunctival GCs than chlorhexidine treatment.

Tear cytokine levels are reduced in patients treated with intravitreal injections.

PURPOSE: To investigate cytokine levels in the tear fluid of patients receiving serial intravitreal injections (IVI) with anti-vascular endothelial growth factor (anti-VEGF) for neovascular age-related macular degeneration (nAMD). METHODS: Concentrations of six cytokines (IFN-γ, IL-1ß, IL-6, IL-8, TNF and VEGF) in tears of patients receiving anti-VEGF in one eye were assayed using multiplex cytometric bead array. The fellow untreated eye served as control. Tear sampling was performed on a single occasion at a minimum of four weeks after IVI. Patients underwent a pre-IVI antisepsis protocol with povidone-iodine. RESULTS: Tear fluid from thirty patients with a mean age of 78.8 years (range 58-90) was assayed. Subjects received a median of 43.5 (range 22-106) IVI in one eye. The median level of IFN-γ was 0.33 (interquartile range (IQR) 0.22-0.52) pg/mg of total protein in injected eyes versus 0.41 (IQR 0.21-1.05) pg/mg in fellow eyes (p = 0.017). For TNF, a median level of 0.12 (IQR 0.08-0.18) pg/mg of total protein was found in injected eyes versus 0.14 (IQR 0.07-0.33) pg/mg of total protein in fellow eyes (p = 0.019). There were no differences between injected and fellow eyes regarding the levels of IL-1ß, IL-6, IL-8 and VEGF. CONCLUSION: Tear fluid in eyes receiving serial IVI with anti-VEGF and preoperative povidone-iodine antisepsis constitutes lower levels of the pro-inflammatory cytokines IFN-γ and TNF compared to fellow eyes. This provides biochemical support of previous findings of reduced signs of inflammation and healthier tear film parameters in patients treated with serial IVI.

Comparing the effect of benzalkonium chloride-preserved, polyquad-preserved, and preservative-free prostaglandin analogue eye drops on cultured human conjunctival goblet cells

Purpose To investigate the effect of benzalkonium chloride (BAK)-preserved latanoprost and bimatoprost, polyquad (PQ)-preserved travoprost, and preservative-free (PF) latanoprost and tafluprost, all prostaglandin analogues (PGAs), on human conjunctival goblet cell (GC) survival. Furthermore, to investigate the effect of BAK-preserved and PF latanoprost on the cytokine secretion from GC. Methods Primary human conjunctival GCs were cultivated from donor tissue. Lactate dehydrogenase (LDH) and tetrazolium dye colorimetric (MTT) assays were used for the assessment of GC survival. A cytometric bead array was employed for measuring secretion of interleukin (IL)-6 and IL-8 from GC. Results BAK-preserved latanoprost and bimatoprost reduced cell survival by 28% (p = 0.0133) and 20% (p = 0.0208), respectively, in the LDH assay compared to a negative control. BAK-preserved latanoprost reduced cell proliferation by 54% (p = 0.003), BAK-preserved bimatoprost by 45% (p = 0.006), PQ-preserved travoprost by 16% (p = 0.0041), and PF latanoprost by 19% (p = 0.0001), in the MTT assay compared to a negative control. Only PF tafluprost did not affect the GCs in either assay. BAK-preserved latanoprost caused an increase in the secretion of pro-inflammatory IL-6 and IL-8 (p = 0.0001 and p = 0.0019, respectively) compared to a negative control, which PF latanoprost did not. Conclusion BAK-preserved PGA eye drops were more cytotoxic to GCs than PQ-preserved and PF PGA eye drops. BAK-preserved latanoprost induced an inflammatory response in GC. Treatment with PF and PQ-preserved PGA eye drops could mean better tolerability and adherence in glaucoma patients compared to treatment with BAK-preserved PGA eye drops. (AU)

A Preservative-Free Approach - Effects on Dry Eye Signs and Symptoms After Cataract Surgery.

Purpose: To compare the effect of treatment with preservative-free dexamethasone, NSAIDs and trehalose/hyaluronic acid eye drops with the preservative benzalkonium chloride containing dexamethasone and NSAIDs after cataract surgery in dry versus non-dry eyes. Patients and Methods: In this prospective randomized intervention study, dry eye tests were performed before and 6 weeks after cataract surgery. Patients were considered as having dry eye, SDE (sign of dry eye), if at least one of the following dry eye tests were abnormal; corneal fluorescein staining (CFS), non-invasive keratograph breakup time (NIKBUT) or tear osmolarity. Patients with SDE were randomly assigned to one of two groups. Group 1 patients were treated with dexamethasone and bromfenac eye drops with the preservative benzalkonium chloride (BAC). Group 2 patients were treated with preservative-free dexamethasone and preservative-free diclofenac, as well as a preservative-free lubricant with trehalose and hyaluronic acid both before and after surgery. Patients with normal tear film status acted as the control group (group 3) and received same treatment as group 1. Results: A total of 215 patients were enrolled six weeks after surgery, the number of patients with SDE decreased significantly in groups 1 and 2 (p <0.001). Subjective symptoms and objective measures including osmolarity, NIKBUT, CFS, and tear film thickness (TFT) improved after surgery, tear production remained unchanged, while corneal sensitivity and meibomian gland dysfunction (MGD) parameters worsened. In the control group with normal tear-film status, SDE increased significantly after the surgery (p <0.001). There were no statistically significant differences in tear film parameters between the three groups after surgery. Conclusion: After cataract surgery, patients with mild to moderate dry eyes may experience improved tear film status and reduced symptoms. However, we found no additional beneficial effect on dry eye parameters with treatment with preservative-free dexamethasone, NSAIDs, and lubricants compared to preservative-containing eye drops.

Heritability of tear fluid cytokines in healthy twins.

PURPOSE: Ocular surface disease is common and it is associated with elevated concentration levels of cytokines in tear fluid. Studies of the normal variation in tear fluid inflammatory markers are lacking. New knowledge may help guide research into ocular surface disease biomarkers and therapeutics. METHODS: In this prospective twin cohort study, healthy individuals were recruited from a population-based registry. Tear fluid was collected with the Schirmer test strips was submerged in phosphate buffered saline and stored at -80° before undergoing 27-cytokine multiplex immunoassay analysis. Broad-sense heritability (h2) of cytokine concentrations was analyzed. RESULTS: 90 participants (23 monozygotic and 22 dizygotic twin pairs) were included. Data availability allowed for heritability analysis of 15 cytokines, and a h2 >50% was seen for 10 cytokines. A statistical power of >80% was achieved for heritability analyses of the cytokines interferon gamma induced protein 10 (h2 = 94.8%), eotaxin (89.8%), interleukin 7 (86.6%), interleukin 1ß (82.2%) and monocyte chemoattractant protein 1 (68.2%). CONCLUSIONS: The tear fluid concentration of several analyzed cytokines was found to be highly heritable. A considerable amount of the inter-individual variation observed for the concentration of certain tear fluid cytokines can be linked to hereditary factors that cannot easily be modified by changing factors in the environment of patients. This suggests that a higher success in ocular surface disease drug discovery may be anticipated for drugs that have targets in specific populations, and points to the importance of emphasizing known preventive measures of ocular surface disease and examinations of close relatives of patients with ocular surface disease, such as dry eye disease.

Sex Differences in the Prevalence of Meibomian Gland Dysfunction: A Mini Review.

PURPOSE: In this review, we aimed to investigate the literature on sex-specific prevalence of meibomian gland dysfunction (MGD) and to determine whether women or men are more at risk for MGD. METHODS: A search was conducted on PubMed using the terms: (Sex OR Gender OR prevalence) AND (Meibomian gland). RESULTS: Twenty-four relevant studies on MGD prevalence were identified, including 10 population-based and 14 hospital-based studies. Among the population-based studies, five studies reported higher rates among men, three studies found no differences, and one study observed higher rates among women. In the hospital-based studies, 10 studies reported no difference, two found higher rates among men, and one found higher among women. In the reviewed literature, there was a considerable variation between studies in terms of quality, sample size, age ranges, diagnostic criteria. CONCLUSIONS: While most of the population-based studies suggest a higher prevalence among men, the majority of clinic-based studies show no significant difference. Further research with larger samples and standardized criteria is needed to determine whether men are indeed more susceptible to MGD.

A comparison between hyaluronic acid and other single ingredient eye drops for dry eye, a review.

Dry eye disease (DED) is a highly prevalent and debilitating condition. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan that has a long history as a safe and effective DED treatment. HA is frequently used as a comparator when assessing other topical DED treatments. This study aims to summarise and critically evaluate the literature describing all isolated active ingredients that have been directly compared with HA in the treatment of DED. A literature search was conducted in Embase using Ovid on the 24th of August 2021 and in PubMed including MEDLINE on the 20th of September 2021. Twenty-three studies met the inclusion criteria, 21 of which were randomised controlled trials. Seventeen different ingredients representing six treatment categories were compared with HA treatment. Most measures showed no significant difference between treatments, suggesting either equivalency of treatments or that studies were underpowered. Only two ingredients were represented in more than two studies; carboxymethyl cellulose treatment appears equivalent to HA treatment, while Diquafosol treatment appears superior to HA treatment. Drop-frequency varied from one to eight drops daily. No single study explained the choice of drop frequency. Nine studies used a HA concentration of 0.1% which may be below therapeutic levels. Nine studies reported using preserved formulations, six of them with differences in preservatives between the compared groups. Thirteen studies were financially linked to industry. No major complications were reported. Studies were not designed to find differences in treatment effects for different types or severities of DED. HA is a good comparator treatment when assessing other DED treatments, although consensus after decades of use is still lacking for best choice of concentration, molecular weight and drop tonicity. Well-designed studies are needed to determine an evidence-based standard for HA treatment to be used as comparator.

Comparing the effect of benzalkonium chloride-preserved, polyquad-preserved, and preservative-free prostaglandin analogue eye drops on cultured human conjunctival goblet cells.

PURPOSE: To investigate the effect of benzalkonium chloride (BAK)-preserved latanoprost and bimatoprost, polyquad (PQ)-preserved travoprost, and preservative-free (PF) latanoprost and tafluprost, all prostaglandin analogues (PGAs), on human conjunctival goblet cell (GC) survival. Furthermore, to investigate the effect of BAK-preserved and PF latanoprost on the cytokine secretion from GC. METHODS: Primary human conjunctival GCs were cultivated from donor tissue. Lactate dehydrogenase (LDH) and tetrazolium dye colorimetric (MTT) assays were used for the assessment of GC survival. A cytometric bead array was employed for measuring secretion of interleukin (IL)-6 and IL-8 from GC. RESULTS: BAK-preserved latanoprost and bimatoprost reduced cell survival by 28% (p = 0.0133) and 20% (p = 0.0208), respectively, in the LDH assay compared to a negative control. BAK-preserved latanoprost reduced cell proliferation by 54% (p = 0.003), BAK-preserved bimatoprost by 45% (p = 0.006), PQ-preserved travoprost by 16% (p = 0.0041), and PF latanoprost by 19% (p = 0.0001), in the MTT assay compared to a negative control. Only PF tafluprost did not affect the GCs in either assay. BAK-preserved latanoprost caused an increase in the secretion of pro-inflammatory IL-6 and IL-8 (p = 0.0001 and p = 0.0019, respectively) compared to a negative control, which PF latanoprost did not. CONCLUSION: BAK-preserved PGA eye drops were more cytotoxic to GCs than PQ-preserved and PF PGA eye drops. BAK-preserved latanoprost induced an inflammatory response in GC. Treatment with PF and PQ-preserved PGA eye drops could mean better tolerability and adherence in glaucoma patients compared to treatment with BAK-preserved PGA eye drops.

Allogeneic mesenchymal stem cell therapy for dry eye disease in patients with Sjögren's syndrome: A randomized clinical trial.

PURPOSE: This double-blinded randomized clinical trial aimed to evaluate the efficacy of injecting allogeneic adipose-derived mesenchymal stem cells (ASCs) into the lacrimal gland (LG) for the treatment of dry eye disease (DED) secondary to Sjögren's syndrome (SS). METHODS: Fifty-four participants with severe DED secondary to SS were included and allocated to either ASCs (n = 20), vehicle (n = 20), or a non-randomized observation group (n = 14). The intervention groups received a single injection of either ASCs or an active comparator (vehicle, Cryostor® CS10) into the LG in one eye, while the observation group received lubricating eye drops only. The primary outcome measure was changes in Ocular Surface Disease Index (OSDI) score and secondary outcome measures were non-invasive tear break-up time, tear meniscus height, Schirmer's test, and Oxford score within a 12-month follow-up. RESULTS: A significant reduction in OSDI score was observed in the ASCs and vehicle groups compared to the observation group. In addition, the ASCs group demonstrated a significant increase in non-invasive tear break-up time compared to the vehicle group at the 4-week follow-up and to the observation group at the 12-month follow-up. A significant improvement in ocular surface staining, tear osmolarity, and Schirmer test score from baseline was also observed in the ASCs group; however, these changes were not significant compared to the other groups. CONCLUSION: Improvement of subjective and objective signs and symptoms of DED was observed in both intervention groups following injection into the LG compared to the observation group. Future studies should investigate the mode-of-action of both injection treatments.

Using machine learning model explanations to identify proteins related to severity of meibomian gland dysfunction.

Meibomian gland dysfunction is the most common cause of dry eye disease and leads to significantly reduced quality of life and social burdens. Because meibomian gland dysfunction results in impaired function of the tear film lipid layer, studying the expression of tear proteins might increase the understanding of the etiology of the condition. Machine learning is able to detect patterns in complex data. This study applied machine learning to classify levels of meibomian gland dysfunction from tear proteins. The aim was to investigate proteomic changes between groups with different severity levels of meibomian gland dysfunction, as opposed to only separating patients with and without this condition. An established feature importance method was used to identify the most important proteins for the resulting models. Moreover, a new method that can take the uncertainty of the models into account when creating explanations was proposed. By examining the identified proteins, potential biomarkers for meibomian gland dysfunction were discovered. The overall findings are largely confirmatory, indicating that the presented machine learning approaches are promising for detecting clinically relevant proteins. While this study provides valuable insights into proteomic changes associated with varying severity levels of meibomian gland dysfunction, it should be noted that it was conducted without a healthy control group. Future research could benefit from including such a comparison to further validate and extend the findings presented here.

Tear and Saliva Metabolomics in Evaporative Dry Eye Disease in Females.

Accurate diagnosis of dry eye disease (DED) is challenging, and even today there is no gold standard biomarker of DED. Hypothesis-free global metabolomic studies of tears from DED patients have great potential to discover metabolites and pathways affected in the pathophysiology of DED, and to identify possible future biomarkers. These metabolites and biomarkers could be important for diagnosing and monitoring disease as well as for new therapeutic targets and strategies. As DED is associated with dry mouth, this study aimed to perform metabolomic analyses of tears and saliva from patients with decreased tear film break-up time but normal Schirmer test, and age-matched controls with both tear production and stability within physiological range. We applied strict inclusion criteria to reduce sampling bias in the metabolomic analyses and selected only age-matched females with Schirmer test values between 10-15 mm/5 min. The tear film analysis arm included 19 patients (with tear film break-up time 0-5 s) and 12 controls (with tear film break-up time 10-30 s), while the salivary analysis arm consisted of a subset which included 18 patients and six controls. Metabolomic analyses were performed using liquid chromatography and high-resolution mass spectrometry. Analyses using a global database search detected a total of 56 metabolites in tear samples that were significantly different between the groups. Of these, several have known associations with DED. These metabolites are present in meibum and have anti-oxidative characteristics or associations with the ocular microbiome, and altered concentrations suggest that they may play a significant role in DED associated with decreased tear film stability. In saliva, hypotaurine levels were lower among patients with tear film instability. In this pilot study, we found different levels of several metabolites in patients with decreased tear film break-up time that may have associations with DED. Future studies are required to replicate our findings and clarify the exact roles of these metabolites.

Greater adherence to a mediterranean diet is associated with lower C-reactive protein (CRP) levels, but not to lower odds of having dry eye disease.

PURPOSE: To investigate the hypothesis that a Mediterranean diet is associated with a lower risk of having dry eye disease (DED) in the general population. METHODS: DED was assessed using the Women's Health Study (WHS) dry eye questionnaire in 58,993 participants from the Dutch Lifelines Cohort with complete available dietary data (20-94 years, 60% female). Level of adherence to a traditional Mediterranean diet was assessed using the modified Mediterranean Diet Score (mMDS). High-sensitivity C-reactive Protein (hsCRP) was included as a marker of whole-body inflammation. Logistic regressions were used to examine the relationship between WHS-defined DED and mMDS, corrected for age, sex, BMI, education, income, and 48 potentially confounding comorbidities. The association between mMDS and hsCRP, and hsCRP and DED, was further explored in separate regressions. RESULTS: Of all participants, 9.1% had DED. In contrast to the hypothesis, higher mMDS levels were associated with greater odds of DED, corrected for demographics, smoking status, BMI, and comorbidities (OR 1.034, 95%CI: 1.015 to 1.055, P = 0.001). Moreover, there was a highly significant relationship between increasing mMDS and lower circulating hsCRP levels; however, there was no significant relationship between hsCRP and DED. CONCLUSIONS: Stronger adherence to a Mediterranean diet does not appear to be associated with lower odds of having DED in the general population. Furthermore, there was no association between hsCRP and DED in this study. However, the previously described link between a Mediterranean diet and lower hsCRP was confirmed in this large population-based study.

Intense pulsed light treatment in meibomian gland dysfunction: Past, present, and future.

Dry eye disease is a highly prevalent condition, which can substantially impair quality of life, work productivity, and vision. It is considered an inflammatory disease and the most common cause is meibomian gland dysfunction. Despite many treatment alternatives being available, including artificial tears, warm compresses, antibiotics, and anti-inflammatory therapy, lasting treatment effects are rare. Over the last two decades, intense pulsed light therapy, after being well established in dermatology, has been gradually introduced to the field of ophthalmology to treat meibomian gland dysfunction. The purpose of the current article is to critically review the clinical studies assessing the use of intense pulsed light to treat meibomian gland dysfunction published to date. The vast majority of the included studies demonstrated improved symptoms and signs, although the degree of efficacy and its duration varied greatly depending on concomitant treatment, number of treatment sessions, and other factors. Several possible mechanisms of action concerning disease propagation and treatment efficacy are discussed. There is still a need for larger, randomised, longitudinal studies to define the most efficacious treatment regime and to predict which patients may benefit the most. More studies are needed on implementing biochemical analyses and machine learning algorithms. Such studies may prove beneficial in predicting treatment effects, defining optimal treatment regimens, and furthering our understanding of the mechanisms of action.

Purinergic 2X 4 (P2X4), but not P2X7, receptors increase cytosolic [Ca2+] and stimulate mucin secretion in rat conjunctival goblet cells to maintain ocular surface health.

Ionotropic purinergic receptors (P2XRs) are activated by ATP and ATP analogs. ATP can be released through ATP-permeable channels such as the pannexin hemichannels. Upon activation, the P2XRs become permeable to Ca2+, a potent stimulator of mucin secretion in conjunctival goblet cells (CGCs). The purpose of this study was to investigate the presence and function of P2XRs in CGCs. We also examined the presence of pannexin hemichannels. Rat first passage CGCs were stained with the goblet cell marker anti-cytokeratin 7 antibody and specific antibodies to P2X1-7 receptors and pannexin 1-3. mRNA expression was determined by RT-PCR using primers specific to P2XRs and pannexins. Proteins were identified with Western blotting (WB) using the same antibodies as for immunofluorescence (IF) microscopy. To study receptor function, CGCs were incubated with Fura 2-AM, exposed to agonists and antagonists, and intracellular [Ca2+] ([Ca2+]i) measured. [Ca2+]i was also measured after knock down of P2X4 and P2X7 receptor expression, and when exploiting P2XR specific characteristics. Lastly, mucin secretion was measured after the addition of several P2XR agonists. All P2XRs and pannexins were visualized with IF microscopy, and identified with RT-PCR and WB. [Ca2+]i was significantly increased when stimulated with ATP (10-7-10-4 M). Suramin, a non-selective P2XR antagonist at 10-4 M did not reduce ATP-induced peak [Ca2+]i. The potent P2X7 agonist, BzATP (10-7-10-4 M) increased the [Ca2+]i, although to a lesser extent than ATP. When measuring [Ca2+]i the effect of repeated applications of ATP at 10-5 or 10-6 M the response "desensitized" after 30-60 s. The P2X4 specific antagonist 5-BDBD decreased the P2X4 agonist, 2MeSATP,-induced [Ca2+]i increase. Furthermore, siRNA against the P2X4R, but not the P2X7R, decreased agonist-induced peak [Ca2+]i. ATP (10-5 M), BzATP (10-4 M) and 2MeSATP (10-5 M) induced mucin secretion. We conclude that all seven P2XRs are present in cultured rat CGCs. Of the P2XRs, only activation of the homotrimeric P2X4R appears to increase [Ca2+]i and induce mucin secretion. The P2X4R in CGCs offers a new therapeutic target for protective mucin secretion.

Anti-Inflammatory and Pro-Resolving Actions of the N-Terminal Peptides Ac2-26, Ac2-12, and Ac9-25 of Annexin A1 on Conjunctival Goblet Cell Function.

Annexin A1 (AnxA1) is the primary mediator of the anti-inflammatory actions of glucocorticoids. AnxA1 functions as a pro-resolving mediator in cultured rat conjunctival goblet cells to ensure tissue homeostasis through stimulation of intracellular [Ca2+] ([Ca2+]i) and mucin secretion. AnxA1 has several N-terminal peptides with anti-inflammatory properties of their own, including Ac2-26, Ac2-12, and Ac9-25. The increase in [Ca2+]i caused by AnxA1 and its N-terminal peptides in goblet cells was measured to determine the formyl peptide receptors used by the compounds and the action of the peptides on histamine stimulation. Changes in [Ca2+]i were determined by using a fluorescent Ca2+ indicator. AnxA1 and its peptides each activated formyl peptide receptors in goblet cells. AnxA1 and Ac2-26 at 10-12 mol/L and Ac2-12 at 10-9 mol/L inhibited the histamine-stimulated increase in [Ca2+]i, as did resolvin D1 and lipoxin A4 at 10-12 mol/L, whereas Ac9-25 did not. AnxA1 and Ac2-26 counter-regulated the H1 receptor through the p42/p44 mitogen-activated protein kinase/extracellular regulated kinase 1/2, ß-adrenergic receptor kinase, and protein kinase C pathways, whereas Ac2-12 counter-regulated only through ß-adrenergic receptor kinase. In conclusion, current data show that the N-terminal peptides Ac2-26 and Ac2-12, but not Ac9-25, share multiple functions with the full-length AnxA1 in goblet cells, including inhibition of histamine-stimulated increase in [Ca2+]i and counter-regulation of the H1 receptor. These actions suggest a potential pharmaceutical application of the AnxA1 N-terminal peptides Ac2-26 and Ac2-12 in homeostasis and ocular inflammatory diseases.

Prevalence of Dry Eye Disease Among Individuals Scheduled for Cataract Surgery in a Norwegian Cataract Clinic.

Purpose: To determine the prevalence of dry eye disease (DED) in patients scheduled for cataract surgery in a Norwegian eye clinic. Patients and Methods: 218 patients scheduled for cataract surgery were examined for DED in one randomly selected eye and questioned regarding symptoms and risk factors. Patients were diagnosed with DED if they fulfilled the DEWS II criteria with symptom score >12/100 with Ocular Surface Disease Index (OSDI) questionnaire, and the presence of any of the three signs: tear osmolarity >307 mOsm/L in either eye or a difference in osmolarity between the two eyes of >8 mOsm/L, corneal fluorescein staining (CSF) ≥ grade 2 and non-invasive tear film breakup time (NIKBUT) of <10 seconds. Additional tests were the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, tear meniscus height (TMH), Schirmer 1, tear film thickness (TFT), corneal sensitivity and meibography (meiboscore). Dry eye test outcomes were correlated with risk factors for DED. Results: The prevalence of DED was 55.5% according to the DEWS II criteria. The abnormal osmolarity percentage was 66.5, while 29.8% had shortened NIKBUT and 19.7% exhibited CFS ≥2. 57% had Schirmer 1 ≤ 10 mm/5 min, and 81.1% had a meiboscore of ≥1. 71.2% of subjects scored positive for DED symptoms using the OSDI questionnaire and 69.3% using SPEED. Logistic regression analysis showed that higher age correlated with a lower OSDI symptom score, reduced corneal sensitivity and increased meibomian gland atrophy. Female sex was associated with higher odds of having DED, abnormal NIKBUT and abnormal CFS. Ocular tests for DED did not correlate with OSDI symptom scores when assessed with Spearman`s rank analysis. Conclusion: The prevalence of DED in an elderly Norwegian population scheduled for cataract surgery is high and associated with female sex. There was a lack of correlation between signs and symptoms of DED.

Future directions in managing aniridia-associated keratopathy.

Congenital aniridia is a panocular disorder that is typically characterized by iris hypoplasia and aniridia-associated keratopathy (AAK). AAK results in the progressive loss of corneal transparency and thereby loss of vision. Currently, there is no approved therapy to delay or prevent its progression, and clinical management is challenging because of phenotypic variability and high risk of complications after interventions; however, new insights into the molecular pathogenesis of AAK may help improve its management. Here, we review the current understanding about the pathogenesis and management of AAK. We highlight the biological mechanisms involved in AAK development with the aim to develop future treatment options, including surgical, pharmacological, cell therapies, and gene therapies.

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).

Rod and Cone Dark Adaptation in Congenital Aniridia and Its Association With Retinal Structure.

Purpose: To characterize the association between dark-adapted rod and cone sensitivity and retinal structure in PAX6-related aniridia. Methods: Dark-adaptation curves were measured after a 5-minute exposure to bright light with red (625 nm) and green (527 nm) 2° circular light stimuli presented at ≈20° temporal retinal eccentricity in 27 participants with aniridia (nine males; 11-66 years old) and 38 age-matched healthy controls. A two-stage exponential model was fitted to each participant's responses to determine their cone and rod thresholds over time. The thicknesses of macular inner and outer retinal layers were obtained from optical coherence tomography images in 20 patients with aniridia and the 38 healthy controls. Aniridia-associated keratopathy (AAK) grade (0-3) and lens opacities were quantified by clinical examination of the anterior segment. Results: The rod-cone break time was similar between patients with aniridia and healthy controls. Dark-adapted cone and the rod thresholds were higher in aniridia compared with healthy controls. In aniridia, foveal outer retinal layer thickness correlated with both final cone and rod thresholds. A multiple regression model indicated that foveal outer retinal layer thickness and age were the main explanatory variables to predict both final cone and rod thresholds in aniridia when the AAK grade was 2 or less. Conclusions: The results show that both rod- and cone-related functions are affected in PAX6-related aniridia and suggest that retinal anatomical and physiological changes extend beyond the area commonly studied in this condition: the central macula.