Search Results (196)

Background and Objectives: Tear film instability and corneal surface irregularity are important sources of variability in keratometric and corneal topographic measurements, particularly affecting astigmatic magnitude and axis. Accurate preoperative biometry is crucial for optimal refractive outcomes in cataract surgery. Dry eye disease (DED) may compromise the reproducibility of keratometric parameters, leading to errors in intraocular lens (IOL) power calculation. This study aimed to evaluate the impact of DED on the reproducibility of keratometric measurements and to assess the effect of a four-week treatment with lipid-containing artificial tears on these parameters in cataract patients. Materials and Methods: This cross-sectional study included 116 patients scheduled for cataract surgery, of whom 65 (56.0%) had DED and 51 (44.0%) served as controls. All patients underwent two preoperative keratometric measurements 10–20 min apart (IOL1 and IOL2). The control group proceeded to surgery the next day, while surgery in the DED group was postponed. Patients with DED received preoperative therapy with lipid-containing artificial tears. Follow-up assessments occurred one month after therapy (keratometric measurement named IOL3) and eight weeks postoperatively. Clinical evaluation included slit-lamp examination, dry eye testing according to Dry eye Workshop II (DEWS II) criteria: Ocular surface Disease Index (OSDI), Tear Break-Up Time (TBUT), Schirmer I, Oxford staining, and meibomian gland assessment), ocular biometry, and postoperative spherical equivalent measurement using an auto ref-keratometer. Nonparametric statistical analyses were applied to evaluate associations between parameters. Results: In the DED group, corneal astigmatism showed a significant difference between IOL1 and IOL2 (Wilcoxon signed-rank test {Z = 2.43; p = 0.015}). Significant changes in predicted IOL power were observed between pretreatment and posttreatment values (t = 2.57; p = 0.013) and between IOL2 and IOL3 (t = 2.23; p = 0.029), indicating improved keratometric stability following tear film therapy. No additional significant correlations were identified. Conclusions: DED adversely affects the reproducibility of keratometric measurements and may compromise IOL power selection. Preoperative identification and treatment of DED, followed by repeated biometry after tear film stabilization, are strongly recommended to enhance refractive accuracy and optimize surgical outcomes in cataract patients. Full article

Background/Objectives: Meibomian gland dysfunction (MGD) has been shown to be more prevalent in patients with keratoconus (KC) in Turkey, Egypt, and Israel but has not been examined in the Palestinian Authority (PA). Therefore, this study compared the prevalence and clinical features of MGD in patients with keratoconus versus healthy controls seen in an optometry clinic in the PA. Methods: Patients with KC and healthy controls who were non-contact lens wearers were recruited. Habitual visual acuity (VA), tear break-up time (TBUT), meibography, meibomian gland (MG) expressibility (MES) and quality score (MQS), and Schirmer test were evaluated. MGD was defined by an Ocular Surface Disease Index (OSDI) Questionnaire score ≥ 13, TBUT < 10 s, and MG loss > Grade 1. Outcomes were compared using Mann–Whitney U tests, Chi-Square tests and Spearman correlation. Results: The study included 33 eyes of 17 KC (mean age: 29.2 ± 7.7, range:19–50) and 27 right eyes of 27 control participants (mean age: 34.2 ± 11.7, range:18–56). MGD was prevalent in 67% of KC and 30% of control participants. VA was significantly worse (0.8 + 0.2 vs. 1.0 + 0.0, p < 0.001), with significantly greater MG loss in the lower eyelids (p = 0.002), and shorter TBUT (4.1 ± 1.5 s vs. 5.7 ± 1.7 s, p < 0.001) in the KC group. No significant differences were found in symptoms, MES, MQS, MG loss in the upper eyelids, or Schirmer test. Conclusions: KC patients exhibited a significantly higher prevalence and severity of MGD signs compared with controls. These findings highlight the importance of comprehensive ocular surface evaluation and management in this population. Full article

Purpose: The aim of this study was to investigate the association between obstructive sleep apnea (OSA) and the prevalence of dry eye disease (DED) and meibomian gland dysfunction (MGD) using the All-of-Us Research Program (AoURP) dataset from a large, demographically diverse U.S. population. Methods: In this cross-sectional, matched case–control study, participants with documented OSA were exactly matched 1:3 by age, gender, race, and ethnicity to controls without OSA. Associations between OSA and DED and MGD were evaluated using univariate and multivariate logistic regression models adjusted for obesity, diabetes, smoking, hypertension, hyperlipidemia, hypothyroidism, and cardiovascular disease at the time of enrollment. Results: Among the 628,649 AoURP participants, 59,804 individuals had OSA and 179,412 matched controls were identified with the same demographics (mean age 61.95 years; 54.0% female; 12.5% Hispanic; 62.3% non-Hispanic White; 15.5% non-Hispanic Black). Compared to controls, OSA participants had significantly higher rates of smoking (13.7% vs. 10.9%), obesity (68.4% vs. 13.2%), diabetes (43.3% vs. 11.7%), hypertension (76.4% vs. 28.2%), hyperlipidemia (74.5% vs. 27.5%), hypothyroidism (24.7% vs. 8.1%), and cardiovascular disease (43.1% vs. 12.8%) (all p < 0.001). Compared to matched controls, the prevalence of DED was significantly higher in the OSA group (19.4% vs. 5.8%), with an adjusted odds ratio (OR) of 1.76 (95% confidence interval (95% CI), 1.70–1.82; p < 0.001). MGD prevalence was also higher in the OSA group (2.6% vs. 1.0%), with an adjusted OR of 1.43 (95% CI, 1.32–1.55; p < 0.001). Conclusions: In this large, demographically diverse U.S. population, obstructive sleep apnea was independently associated with a higher prevalence of both dry eye disease and meibomian gland dysfunction. These findings provide large-scale U.S. evidence and suggest that screening for ocular surface disease may be warranted in patients with OSA to improve detection and management. Full article

Objectives: To compare the effects of two preoperative dry eye treatments—3% diquafosol sodium (DQS) and intense pulsed light with meibomian gland expression (IPL-MGX)—on refractive accuracy in cataract surgery and identify tear break-up time (TBUT) thresholds predictive of refractive success. Methods: In this prospective, paired-eye study, 62 patients (124 eyes) with meibomian gland dysfunction underwent bilateral cataract surgery with the same trifocal intraocular lens. One eye received DQS, while the fellow eye underwent four IPL-MGX sessions before biometry. Postoperative absolute prediction error (P-SE) was compared. TBUT and higher-order aberrations (HOAs) were evaluated. Logistic regression identified predictors of refractive accuracy, and receiver operating characteristic (ROC) analysis assessed the predictive value of TBUT for P-SE thresholds of <0.25 D and <0.50 D. Results: P-SE was significantly lower in IPL-MGX–treated eyes than in DQS-treated eyes (mean paired difference −0.11 D, p < 0.001). Success rates within <0.25 D and <0.50 D were higher with IPL-MGX (p < 0.01). TBUT and HOAs were predictors in univariate models, but only TBUT remained significant in the multivariable analysis (odds ratio, 4.90 per 1-s increase; 95% confidence interval, 1.92–12.51; p < 0.001). ROC analysis supported TBUT cutoffs of 7 s (<0.25 D) and 6 s (<0.50 D). Conclusions: IPL-MGX may improve refractive accuracy compared to DQS. TBUT appeared to be the most consistent predictor, and achieving ≥6 s was associated with higher likelihood of refractive success. Full article

Background/Objectives: Demodex mites are a common yet underdiagnosed cause of ocular surface diseases, including blepharitis and meibomian gland dysfunction (MGD). Traditional diagnosis via microscopic examination is labor-intensive and time-consuming. This study aimed to develop a deep learning-based system for the automated detection and quantification of Demodex mites from microscopic eyelash images. Methods: We collected 1610 microscopic images of eyelashes from patients clinically suspected to have ocular demodicosis. After quality screening, 665 images with visible Demodex features were annotated and processed. Two deep learning models, YOLOv11 and RT-DETR, were trained and evaluated using standard metrics. Grad-CAM visualization was applied to confirm model attention and feature localization. Results: Both YOLO and RT-DETR models were able to detect Demodex mites in our microscopic images. The YOLOv11 boxing model revealed an average precision of 0.9441, sensitivity of 0.9478, and F1-score of 0.9459 in our detection system, while the RT-DETR model showed an average precision of 0.7513, sensitivity of 0.9389, and F1-score of 0.8322. Moreover, Grad-CAM visualization confirmed the models’ focus on relevant mite features. Quantitative analysis enabled consistent mite counting across overlapping regions, with a confidence level of 0.4–0.8, confirming stable enumeration performance. Conclusions: The proposed artificial intelligence (AI)-based detection system demonstrates strong potential for assisting ophthalmologists in diagnosing ocular demodicosis efficiently and accurately, reducing reliance on manual microscopy and enabling faster clinical decision making. Full article

Purpose: This study investigates the association between obstructive sleep apnea (OSA), dry eye disease (DED), and glaucoma, focusing on the impact of positive airway pressure (PAP) usage and air leakage. Methods: This retrospective cross-sectional study included 57 adults with polysomnography-confirmed OSA between 2010 and 2023. Participants were grouped into PAP users (PAP+, n = 40) and non-users (PAP−, n = 17). Ocular assessments included tear film break-up time, Schirmer’s test, Oxford staining, meibomian gland evaluation, intraocular pressure, cup-to-disc (C/D) ratio, and retinal nerve fiber layer thickness. PAP device data (usage duration and air leak rate) and OSA severity metrics were recorded. Group comparisons used chi-square and Student’s t-test, and regression analyses identified associations between PAP leakage and ocular parameters. Results: Among the 57 OSA patients, PAP users showed a trend toward a higher risk of glaucoma (OR = 0.83) and DED (OR = 0.69) compared to non-users, but neither trend was statistically significant. PAP users had significantly more severe OSA, including longer N1 sleep stage (p = 0.0005), higher apnea-hypopnea index (AHI, p = 0.0001), and poorer oxygenation. PAP leakage: 95% (mean = 25.84 L/min) exceeded the 24 L/min threshold specified in ResMed’s clinical guidelines, suggesting suboptimal therapy. Higher PAP leak was significantly associated with a lower Schirmer’s test value (p = 0.031) and a higher C/D ratio (p = 0.040) on regression analysis. However, no significant differences were found in ophthalmic parameters between PAP+ and PAP− groups. Conclusions: Suboptimal PAP therapy as mask leakage or nocturnal hemodynamic changes may worsen evaporative dry eye and affect intraocular pressure. Our findings highlight the association between PAP mask leakage and reduced tear production, and suggest that OSA-related optic nerve stress may persist unless both hypoxia and nocturnal IOP fluctuations are properly managed. However, due to the relatively small sample size and retrospective cross-sectional design, future prospective studies with larger cohorts are needed to confirm these associations. Full article

Purpose: This study aims to investigate whether two stress keratins, KRT6A or KRT17, label self-renewing stem cells (SCs) in adult mouse Meibomian gland (MG), the palpebral conjunctiva (PC) homeostasis, and to explore the mechanisms regulating their expression. Methods: KRT6A and KRT17 expression in adult mouse MG and PC were examined by single-nucleus RNA sequencing and immunofluorescence (IF). Lineage-tracing experiments were performed using Krt6a-Cre^ERT2 and Krt17-Cre^ERT2 mice carrying the Rosa26R^nTnG or Rosa26R^mTmG reporter. As Hedgehog (Hh) signaling, the histone deacetylase HDAC3, and the transcription factor KLF4 regulate KRT6A and KRT17 in other contexts, IF was conducted to assess the in vivo effects of overexpression of the Hh pathway activator GLI2ΔN, and inducible epithelial deletion of Hdac3 or Klf4 on KRT6A and KRT17 expression in the MG and PC. Results: KRT6A and KRT17 are primarily expressed in the MG central duct and ductules. KRT6A also shows robust expression in PC. Lineage tracing indicated that Krt17 labels self-renewing SCs in the MG, whereas Krt6a labels SCs in the PC. GLI2ΔN overexpression induced ectopic KRT17 expression in MG acini and PC but did not affect KRT6A expression in either MG or PC. Hdac3 deficiency caused expanded expression of KRT6A and KRT17 in MG acini, ectopic KRT17 expression in PC, and increased KRT6A expression in PC basal layer. Klf4 deletion resulted in ectopic KRT17 expression in PC but did not influence KRT6A expression in MG or PC. Conclusions: Krt6a- and Krt17-expressing cells contribute to adult PC and MG homeostasis, respectively. KRT17 expression is enhanced by GLI2ΔN, and suppressed by HDAC3 and KLF4, whereas KRT6A expression is controlled only by HDAC3. These findings provide important biological insight into tissue-specific maintenance mechanisms and may inform future therapeutic strategies for regenerating MG and PC tissues affected by SC exhaustion or dysregulation. Full article

Dry Anophthalmic Socket Syndrome (DASS) is a multifactorial condition that affects roughly half of all prosthetic eye wearers and remains frequently underrecognized. It is characterised by symptoms such as dryness, discomfort, discharge, and inflammation of the socket surface. Diagnostic criteria include validated symptom questionnaires (e.g., OSDI, DEQ-5, SANDE) and at least one clinical sign such as conjunctival staining, blepharitis, or reduced tear meniscus height. This review describes the anatomical, cellular, and molecular changes associated with DASS. Meibomian gland dysfunction is common, with a significant reduction in gland density and structure. Goblet cell density is also often decreased, particularly in the tarsal and bulbar conjunctiva, although findings may be affected by topical treatments. Increased conjunctival inflammation—evidenced by immune cell infiltration and elevated markers such as MMP-9 and ICAM-1—is frequently observed, particularly in the posterior socket lining. Oxidative stress, mediated by dysregulated NOX4, KEAP1, and NRF2 expression, appears to play a contributory role. Additional factors influencing DASS include eyelid malpositions such as entropion and ectropion, prosthesis smoothness and amount of tear film production. Poor hygiene practices and environmental factors may exacerbate symptoms. Given its multifactorial aetiology, DASS requires a complex management strategy targeting inflammation, tear film instability, mechanical irritation, eyelid position and patient education. Increased awareness, standardised diagnostics, and evidence-based care protocols are critical to improving outcomes for prosthetic eye wearers. Full article

Background: Type 2 diabetes mellitus (T2DM) is increasingly recognized as affecting not only the retina but also the ocular surface. Chronic hyperglycemia can disrupt meibomian gland function, reduce tear secretion, and impair corneal sensitivity, leading to tear film instability and symptoms of dry eye disease. However, previous studies have reported variable findings, and the extent of these alterations remains uncertain. Methods: Following PRISMA guidelines, this systematic review and meta-analysis evaluated observational studies that compared tear film parameters between adults with T2DM and non-diabetic controls. Eligible studies assessed one or more of the following: invasive or non-invasive tear break-up time, Schirmer test, tear meniscus height, or Ocular Surface Disease Index (OSDI). Results: Twenty-four studies involving approximately 3500 eyes were included. Most reported significantly reduced tear stability and secretion in diabetic participants compared with controls. Tear break-up times were consistently shorter in T2DM, indicating a less stable tear film. Schirmer test results demonstrated lower tear production correlated with diabetes duration and poor glycemic control. Tear meniscus height was modestly reduced in T2DM, reflecting decreased tear reservoir volume. Subjective symptoms, as measured by OSDI, were generally higher among patients with T2DM, suggesting greater ocular surface discomfort. Conclusions: T2DM is strongly associated with tear film instability, reduced tear secretion, and increased dry eye symptoms. These findings suggest that diabetic care should include routine ocular surface assessment and highlight the need for standardized, longitudinal investigations. Full article

Background: Urban air pollution, particularly fine particulate matter (PM2.5 and PM10), poses health risks, including damage to the ocular surface. This pilot study (BIKE-EYE) aimed to assess ocular exposure to airborne pollutants during bicycle commuting and to evaluate particle presence in human tear fluid. Methods: Fifteen healthy volunteers wore portable sensors measuring PM2.5 and PM10 during daily bike commutes over six months. Exposure was calculated as time-weighted integrals over the ten days preceding an ophthalmologic exam assessing conjunctival hyperemia, epithelial damage, tear film quality, and meibomian gland function. Ocular symptoms were assessed via the Ocular Surface Disease Index (OSDI). Tear samples were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Results: Higher pollutant exposure was significantly associated with conjunctival hyperemia and corneal epithelial damage, while temperature and humidity showed no effect. OSDI scores moderately correlated with PM levels. SEM/EDS analysis confirmed airborne particles in post-exposure tear samples, including carbonaceous material, aluminosilicates, iron, and sulfur compounds. Conclusions: Ocular surface alterations and conjunctival hyperemia were significantly associated with air pollution exposure, while subjective symptoms showed weaker trends. The detection of particulate matter in human tear fluid supports the use of the ocular surface as a sensitive, non-invasive tool for biomonitoring. These findings highlight its potential role in early warning systems for pollution-related health effects, with implications for public health surveillance and urban planning. Full article

The eyelid skin represents a unique anatomical and immunological interface between the external environment and the ocular surface. Due to its structural delicacy, dense vascularization, and continuous exposure to microbial and environmental antigens, it is a primary target of inflammatory and autoimmune processes. This review aims to synthesize current molecular insights into eyelid skin inflammation, with particular emphasis on autoimmune mechanisms. We discuss autoimmune diseases such as ocular cicatricial pemphigoid, pemphigus, discoid and systemic lupus erythematosus, and thyroid-associated orbitopathy, focusing on the roles of T helper cell subsets, pro-inflammatory cytokines (IL-1β, IL-6, IL-17, TNF-α), and autoantibody-mediated complement activation. We further address the contribution of the periocular microbiome and meibomian gland dysfunction. Diagnostic advances, including confocal microscopy, in vivo molecular imaging, and tear proteomics, are highlighted alongside emerging targeted therapies such as biologics and small molecules directed at IL-17, TNF-α, and B-cell activity. Finally, we propose future perspectives for precision medicine approaches, integrating omics technologies and microbiome-based therapies to advance personalized management of eyelid skin inflammation. Full article

Objectives: To compare the safety and efficacy of a prototype electronic heating device, Meiboleyes^®, with the BRUDER Moist Heat Eye Compress for the treatment of Meibomian Gland Dysfunction (MGD). Methods: Adults with evidence of active MGD (Ocular Surface Disease Index [OSDI] score ≥ 13, fluorescein tear break-up time [TBUT] < 10 s and meibomian gland secretion score ≤ 12 for 15 glands of the lower lid) were enrolled in this prospective, randomised, parallel group, investigator-masked dispensing study (Australian New Zealand Clinical Trials Registry–ACTRN12624000175572). Meibomian gland secretion (MGS) score and number of meibomian glands yielding liquid secretion (MGYLS), lipid layer thickness, TBUT, ocular physiology and subjective symptoms were measured at baseline, and 2 weeks and 6 weeks following treatment. Linear mixed model analysis was conducted to compare the two groups and changes over time. Results: Ten participants (average age 38.7 ± 14.5 years) in the Meiboleyes^® test group, and 10 participants (average age 38.9 ± 14.8 years) in the BRUDER control group completed the study. MGS and MGYLS significantly improved in both treatment groups from baseline to the 2-week and 6-week follow-up visits (p ≤ 0.006). Significant improvements in TBUT (5.5 ± 1.8 vs. 8.3 ± 2.1 s, p = 0.044), OSDI scores (45.2 ± 15.1 vs. 27.4 ± 12.9, p = 0.027) and visual analogue scale dryness (55.3 ± 27.2 vs. 28.0 ± 23.9, p = 0.023) were observed in the Meiboleyes^® group only after 6 weeks of treatment. No other significant differences were observed over time or between groups. Eight treatment-related adverse events were reported in the Meiboleyes^® group compared to seven in the BRUDER group. All resolved without sequalae. Conclusions: The prototype Meiboleyes^® device was safe and effective for use as an at-home treatment for MGD when used twice daily for six weeks. Improvements in meibomian gland function were comparable to the BRUDER Moist Heat Eye Compress, but significant improvements in tear film stability and subjective comfort after 6 weeks of treatment were observed in the Meiboleyes^® group only. Full article

Background: The use of preservative agents in eye drop solutions may worsen symptoms of ocular surface disease, which is a highly prevalent syndrome worldwide. Preservatives are often used in pharmacotherapy of glaucoma, another disease concerning tens of millions of people around the globe. These numbers are predicted by the World Health Organization and are predicted to increase with time due to constant aging of populations. Methods: PubMed and Scopus databases were searched for articles investigating the topic of ocular surface disease in relation with glaucoma pharmacotherapy, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The aim of this review is to summarize the effect of various solvents used in drug formulations and ways to quantify their impact on the ocular surface. Discussion and Conclusions: Topical ophthalmic preservative-free formulations are better tolerated and less burdensome for all patients. They should be considered especially for glaucoma patients, who are expected to take medications for years, up to decades or a lifetime in many cases. Due to the chronicity of dry eye disease and the lack of reliable ways for lacrimal and meibomian gland renewal, primary prophylaxis is of uttermost importance. Unfortunately, despite the development of many measuring devices, the standardization of diagnostic methods poses a challenge due to high variability of results which are influenced by a myriad of factors—local, internal, and external. Full article

Background/Objectives: This study aimed to assess the effectiveness of a combination therapy comprising eyelid hygiene, intense pulsed light (IPL), and meibomian gland expression in patients with meibomian gland dysfunction (MGD). Methods: This retrospective study included MGD patients who completed at least three sessions of combination therapy administered at 4-week intervals, with a minimum follow-up period of 6 months. Ocular surface parameters were evaluated at baseline and at 1, 3, and 6 months after treatment initiation. Based on the clinical response following the initial three sessions, patients were categorized into either the standard treatment group (3 sessions) or the extended treatment group, who received three additional sessions of the same combination therapy. Results: A total of 107 patients (77 females; 30 males) were enrolled. 74 patients received standard treatment, and 33 received extended treatment. In the standard group, significant improvements compared with baseline were observed in the Ocular Surface Disease Index score, non-invasive tear break-up time, corneal staining, lid margin plugging, telangiectasia, and the meibomian gland expressibility score. Conversely, in the extended group, only the meibomian gland expressibility score showed significant improvements at the 3-month follow-up. Conclusions: The standard combination therapy resulted in significant and durable improvements in approximately 70% of MGD patients, with effects persisting for at least 3 months post-treatment. These findings support the clinical utility of this multimodal approach and highlight the need for biomarkers to predict treatment response. Full article

Meibum—a lipid-rich secretion produced by holocrine Meibomian glands (MG)—plays a central role in maintaining ocular surface homeostasis in humans. Previously, changes in MG lipidomes induced by inactivation of critical genes of meibogenesis, such as Elovl3, Soat1, Awat2, Sdr16c5/Sdr16c6, and others were shown to cause MG dysfunction (MGD) and dry eye in experimental animals. Here, we describe the impact of the changes in the lipid composition of meibum on its protective properties, specifically physiologically relevant thermotropic characteristics, using various mutant and wild-type animal models, and comparing them with healthy human subjects and patients with MGD. Meibum samples were analyzed using liquid chromatography/mass spectrometry (LC/MS) and differential scanning microcalorimetry (DSC). We found that any change in the balance between major lipid classes in meibum—wax esters, cholesteryl esters, triacylglycerols, and free cholesterol—cause detrimental changes in its thermotropic properties, loss of cohesiveness, and abnormal expressibility from MG, resulting in MGD-like phenotypes of the eyes and adnexa. We conclude that tested knockout mice can be valuable models for modeling and studying MGD. A combination of LC/MS and DSC can be a powerful diagnostic tool and may help to diagnose MGD and other pathologies, as well as determine their molecular mechanisms. Full article