Search Results (137)

Background/Objectives: Corneal epithelial thickness (CET) alterations reflect distinct mechanisms in aqueous-deficient and evaporative dry eye disease (DED) subtypes. In this study, we compare the CET profiles between patients with Sjögren’s syndrome (SS) and those with meibomian gland dysfunction (MGD) to elucidate the underlying mechanisms. Methods: We retrospectively analyzed 30 patients with SS and 30 age- and sex-matched with MGD. Assessments included corneal staining, Ocular Surface Disease Index (OSDI), tear meniscus height (TMH), non-invasive breakup time, lipid layer thickness (LLT), and anterior segment optical coherence tomography (AS-OCT) CET mapping. Regional CET and superior–inferior asymmetry were compared. Results: The SS group exhibited higher corneal staining scores (2.18 ± 1.23 vs. 1.03 ± 1.18, p = 0.001) and lower TMHs (0.14 ± 0.06 vs. 0.18 ± 0.07 mm, p = 0.013), while the MGD group reported greater OSDI scores (40.39 ± 22.49 vs. 31.25 ± 22.81, p = 0.029). A significantly thinner central epithelium (p = 0.043) and localized inferior paracentral thinning (2–5 mm zone, p = 0.008) were noted in SS. Corneal staining was identified as the primary independent predictor of central and inferior CET reduction in both groups. In the MGD group, LLT was associated with the preserved inferior CET (p = 0.045) and superior–inferior thickness difference (p = 0.015). Conclusions: Distinct structural signatures are observed between DED subtypes. SS features central/inferior thinning from aqueous deficiency-mediated friction, whereas MGD shows a relatively preserved epithelial thickness influenced by LLT. Regional CET analysis may provide mechanistic insights into DED subtyping. Full article

Background: Meibomian gland dysfunction (MGD) is a major contributor to evaporative dry eye disease, yet reported prevalence estimates vary widely across studies, largely due to differences in diagnostic criteria, study populations, and settings. We conducted a systematic review and meta-analysis to synthesize available evidence on the prevalence of MGD in adults aged ≥40 years and to examine sources of heterogeneity across studies. Methods: We systematically searched PubMed, Web of Science, Scopus, and Google Scholar from inception to November 2025 for observational studies reporting the prevalence of MGD in adult populations. Random-effects meta-analysis of proportions was performed. Subgroup analyses were conducted by study setting and diagnostic approach. Between-study heterogeneity was quantified using the I² statistic. Results: Eight observational studies from Singapore, Spain, Russia, Iran, China, Japan, and New Zealand, comprising 20,518 participants, met inclusion criteria. Reported prevalence of MGD varied substantially across studies. The pooled prevalence estimate was 87.08% (95% CI: 65.32–96.02%); however, heterogeneity was extreme (I² > 99%), indicating substantial variability across populations and study methods. This pooled estimate should be interpreted with caution and not as a single representative global prevalence. Studies using clinical signs alone tended to report higher prevalence than those incorporating both signs and symptoms. Differences in study setting and diagnostic definitions accounted for a significant proportion of heterogeneity. Conclusions: MGD appears to be commonly detected in adults aged ≥40 years; however, prevalence estimates vary markedly depending on diagnostic criteria and study design. Given the extreme heterogeneity, pooled prevalence estimates should be interpreted with caution and not as a single global prevalence value. Standardized diagnostic definitions and population-based studies using harmonized methodologies are needed to generate more comparable and clinically interpretable estimates of MGD burden. Full article

Background/Objectives: To evaluate the relationships between meibomian gland dysfunction (MGD), ocular surface parameters, and matrix metalloproteinase-9 (MMP-9)-mediated inflammation in glaucoma patients, we specifically assessed the impact of prostaglandin analogue use, preservative exposure, and number of medications. Methods: This retrospective cross-sectional study included patients treated with topical antiglaucoma medications for at least six months. Meibomian gland expressibility, meibum quality, and MGD grade were assessed along with tear film break-up time (TBUT), Schirmer I test, and Oxford staining score. Tear MMP-9 levels were measured using a Point-of-Care immunoassay (InflammaDry^®) and graded on a 0 to 4 scale. Results: Elevated MMP-9 grades were significantly correlated with worsening meibum expressibility, meibum quality, and MGD grade (all p < 0.001), whereas no significant associations were found with traditional parameters such as TBUT and Schirmer I test. Prostaglandin analogue use was associated with worse meibomian gland parameters and higher MMP-9 levels compared to non-use. Patients receiving preservative-containing medications exhibited poorer meibomian gland parameters and MMP-9 levels, as well as worse corneal staining scores. An increased number of medications was associated with a stepwise deterioration in meibomian gland function and elevated MMP-9 levels. Conclusions: Prostaglandin analogue use, preservative exposure, and increased number of medications are significant factors associated with the exacerbation of MGD and ocular surface inflammation. Semi-quantitative grading of tear MMP-9 revealed a stepwise association with meibomian gland dysfunction severity that was not detected by conventional dry eye metrics, indicating that MMP-9 may be considered a potential indicator of subclinical ocular surface inflammation in glaucoma patients. Full article

Thyroid eye disease (TED) is an autoimmune inflammatory disorder primarily affecting orbital tissues, but ocular surface and adnexal involvement represent a frequent and clinically significant component of disease burden. Beyond mechanical exposure resulting from eyelid retraction and proptosis, TED-associated ocular surface disease arises from complex interactions between immune activation, epithelial stress, glandular dysfunction, and altered neuro-epithelial signaling. Increasing use of systemic immunomodulatory therapies, biologics, and orbital radiotherapy has improved control of orbital inflammation; however, their molecular and cellular effects on ocular surface homeostasis remain incompletely defined. This review summarizes current evidence on the cellular and molecular mechanisms underlying ocular surface dysfunction in TED and examines how disease-modifying therapies influence epithelial integrity, tear film stability, meibomian and lacrimal gland function, and local immune signaling. Key pathways discussed include cytokine-mediated inflammation, thyroid-stimulating hormone receptor and insulin-like growth factor-1 receptor crosstalk, pro-fibrotic signaling, neuro-inflammatory mechanisms, and epithelial stress responses involving mitogen-activated protein kinase and nuclear factor kappa B pathways. We further highlight the challenge of disentangling therapy-induced molecular effects from persistent exposure-related mechanical stress. Understanding how TED therapies modulate ocular surface and adnexal homeostasis is essential for optimizing integrated management strategies that address both orbital inflammation and long-term ocular surface stability. Full article

Background/Objectives: To investigate whether chronic cosmetics use near or directly on the eyelid margin contributes to tear film instability and meibomian gland dysfunction. Methods: Subjects were enrolled in one of three groups: those who rarely wear makeup (No-M), those who wear it frequently but only outside the eyelid margin (Min-M), and those who wear it frequently and directly on the eyelid margin (W-M). Subjects were assessed for dry eye signs and symptoms by a masked examiner. Lipid layer thickness (LLT), tear meniscus height, meibomian gland excreta grade, number of glands secreting, corneal and conjunctival staining and tear breakup time were assessed. Results: 10 No-M, 18 Min-M, and 21 W-M subjects completed the study. Average fluorescein breakup time was 4.6 s in each group (p = 0.839, 1-way ANOVA). There were higher scores (worse findings) in the marginal eyeliner sample for symptoms (modified Schein, OSDI, SPEED), Oxford and total NEI staining and lower lid meibomian secretions. The W-M group demonstrated a statistically significant increase in the meibomian gland excreta grade (a worsening) compared to the No-M group (mean grades 1.2 and 0.55 respectively; Tukey test, adjusted p < 0.05, 95% CI 0.055–1.187). LLT, tear breakup time, eyelid marginal signs, and meibomian gland dropout had no differences among groups. Conclusions: Eyeliner wear both outside and on the eyelid margin demonstrated increased ocular staining and decreased gland excretion quality, compared to non-makeup users. The meibomian gland excreta decrement may lead to worsening meibomian gland function and potentially glandular atrophy over time. Full article

Dry eye disease (DED) is a complex, multifactorial, progressive disease that has consequences both for individuals and society. Symptoms reported by patients include discomfort in the eye and periodic blurred vision, while in the broader perspective, the disease is associated with economic burdens and challenges for healthcare systems. Globally, dry eye disease remains a growing problem observed in many countries. It is estimated that symptoms of dry eye syndrome occur in approximately 10 to 20 per cent of people over the age of 40. This prevalence is on the rise, which is associated with both the aging population and increased incidence among younger adults. In this group, factors such as contact lens wear and prolonged use of digital devices are considered to be contributing factors. Further epidemiological studies, conducted in different regions of the world, covering diverse populations and a wide range of age groups, with a particular focus on younger cohorts, may contribute to a more accurate understanding of the prevalence of dry eye disease. There are more and more methods of diagnosing DED. In addition to well-known procedures like the Schirmer test or tear break-up time, there are also methods that focus on the evaluation of the tear film or imaging of the ocular surface. Moreover, usage of artificial intelligence is also playing a significant role in it. However, the key issue in individual cases is introducing the most effective treatment based on combining available substances, including corticosteroids, antibiotics and supplements, which leads to a reduction in inflammation and improvement in visual comfort. Full article

Background/Objectives: Rosacea is a chronic inflammatory dermatosis that may involve the eye, causing surface and adnexal damage that can precede cutaneous signs. Detecting subclinical ocular changes is clinically important because early ocular surface dysfunction may be missed on routine examination yet progress to corneal complications, allowing earlier preventive management when identified. We prospectively evaluated subclinical ocular alterations in cutaneous rosacea using a combined, fully non-invasive high-tech imaging workflow—tear film interferometry, infrared meibography, and exploratory retinal optical coherence tomography angiography (OCT-A)—including patients without clinically evident ocular involvement. Methods: Sixteen patients with cutaneous rosacea (mean age 44.3 ± 11.2 years; 4 males, 12 females) were enrolled and divided into: Group 1—rosacea with clinically evident ocular involvement (n = 11); Group 2—rosacea without clinical ocular involvement (n = 5). Six age-matched healthy subjects served as controls (Group 3). All underwent LipiView II^® interferometry and meibography to quantify lipid-layer thickness (LLT, nm) and meibomian gland (MG) loss score (1 = normal–4 = severe), plus retinal OCT-A (Optovue Inc., Fremont, CA, USA). ANOVA with post hoc Tukey test assessed inter-group differences. Results: OCT-A showed no significant alterations in superficial or deep retinal plexuses across groups (p > 0.05). Conversely, LLT was significantly reduced in both rosacea groups vs. controls (OD: 45.5 ± 21.4 nm and 67.4 ± 10.1 nm vs. 92.7 ± 8.2 nm; OS: 40.4 ± 15.3 nm and 66.4 ± 10.1 nm vs. 96.0 ± 6.7 nm; p < 0.001). MG score was markedly higher (worse) in rosacea (OD: 3.63 ± 0.50 and 3.20 ± 0.83 vs. 1.83 ± 0.75; OS: 3.45 ± 0.68 and 3.40 ± 0.54 vs. 1.66 ± 0.81; p < 0.001). Ocular symptoms were reported by 85% of patients yet slit-lamp examination revealed surface alterations in 58% of asymptomatic cases. Conclusions: Tear film interferometry and meibography detect early ocular surface impairment in rosacea—even in the absence of clinical signs—while retinal microvasculature appears unaffected. Routine ophthalmologic screening of all rosacea patients could enable prompt treatment of subclinical dysfunction, potentially preventing corneal complications. Retinal OCTA metrics were not significantly different in this small pilot cohort, and these negative findings should be interpreted cautiously pending larger studies. Full article

Sebaceous glands (SGs) and their specialized subtype, Meibomian glands (MGs), play essential roles in skin and ocular surface homeostasis by producing lipids that maintain barrier integrity and stabilize the tear film. Dysregulation of SG and MG biology contributes to a spectrum of disorders, ranging from benign hyperplasia to sebaceous carcinoma and age-related MG dysfunction. Accumulating evidence highlights the importance of epigenetic regulation, including histone modifications, DNA methylation, and non-coding RNAs (ncRNAs), in controlling SG and MG development, homeostasis, and disease susceptibility. Notably, histone modifiers and ncRNAs modulate acinar differentiation, lipid synthesis, and progenitor cell function. Despite these advances, many epigenetic mechanisms, such as histone lactylation, sumoylation, and phosphorylation, remain underexplored, and several common SG/MG disorders, including chalazion and seborrhea, lack mechanistic studies at the epigenetic level. This review synthesizes current knowledge on SG and MG biology, emphasizing epigenetic regulation, and highlights critical gaps to guide future research aimed at improving the understanding and treatment of SG- and MG-related disorders. Full article

PAX6 haploinsufficiency-related congenital aniridia is frequently associated with ocular surface disease, including meibomian gland dysfunction (MGD), dry eye, limbal stem cell deficiency (LSCD), aniridia-associated keratopathy (AAK), and inflammation. This study measured ocular surface temperature (OST) at the corneal center and four paracentral points (2 mm from center) in patients with congenital aniridia and examined factors influencing OST. Forty-five eyes from 26 aniridia patients (55.6% female; 26.29 ± 17.78 years) with PAX6 pathogenic variants and 47 eyes from 25 controls (68.1% female; 24.81 ± 4.73 years; p = 0.1639) were included. Body temperature, OSDI, and OST (TG-1000) were recorded; clinical assessment evaluated MGD, LSCD, AAK, iris malformation, epithelial defects, Salzmann nodules, glaucoma and previous ocular surgery. Body temperature and OSDI did not differ in aniridia and controls (p ≥ 0.606). LSCD was mainly Grade 2 (46.7%) or Grade 4 (40.0%), and AAK Grade 1 (33.3%) or Grade 2 (31.1%). MGD affected 51.1%, Salzmann nodules 22.2%, epithelial defects 2.2%, glaucoma 60.0%, and previous ocular surgery 35.5%. Superior OST was higher in aniridia (34.98 ± 0.55 °C vs. 34.75 ± 0.47 °C; p = 0.012). Exploratory univariate analyses identified that higher AAK grade correlated with lower inferior OST (p = 0.030), iris malformation with reduced central/paracentral OST (p ≤ 0.029), and Salzmann nodules with lower OST overall (p ≤ 0.011). However, in a multivariate model, age, Salzmann nodular degeneration, and prior ocular surgery emerged as key determinants of OST. OST may serve as a noninvasive biomarker in congenital aniridia. Full article

Meibomian gland dysfunction (MGD) is a leading cause of dry eye disease, assessable through gland atrophy degree. While deep learning (DL) has advanced meibomian gland (MG) segmentation and MGD classification, existing methods treat these tasks independently and suffer from domain shift across multi-center imaging devices. We propose ADAM-Net, an attention-guided unsupervised domain adaptation multi-task framework that jointly models MG segmentation and MGD classification. Our model introduces structure-aware multi-task learning and anatomy-guided attention to enhance feature sharing, suppress background noise, and improve glandular region perception. For the cross-domain tasks MGD-1K→{K5M, CR-2, LV II}, this study systematically evaluates the overall performance of ADAM-Net from multiple perspectives. The experimental results show that ADAM-Net achieves classification accuracies of 77.93%, 74.86%, and 81.77% on the target domains, significantly outperforming current mainstream unsupervised domain adaptation (UDA) methods. The F1-score and the Matthews correlation coefficient (MCC-score) indicate that the model maintains robust discriminative capability even under class-imbalanced scenarios. t-SNE visualizations further validate its cross-domain feature alignment capability. These demonstrate that ADAM-Net exhibits strong robustness and interpretability in multi-center scenarios and provide an effective solution for automated MGD assessment. 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

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