The international workshop on meibomian gland dysfunction: report of the subcommittee on the epidemiology of, and associated risk factors for, MGD

Correlation between meibomian gland dysfunction and sebaceous adenitis in dogs

BACKGROUND

Sebaceous adenitis (SA) is an immune-mediated disease targeting the sebaceous glands. Meibomian gland dysfunction is a disease affecting meibomian glands with inflammatory features. Sebaceous and meibomian glands share anatomical, physiological and embryological similarities. The involvement of meibomian glands in dogs with SA is currently unknown.

OBJECTIVES

To evaluate meibomian glands in dogs affected by SA and compare them with healthy dogs.

ANIMALS

Eighteen dogs were enrolled. Nine dogs with SA were retrospectively identified from clinical records and represented the case group. Nine healthy, breed- and age-matched dogs were prospectively enrolled in the control group.

MATERIALS AND METHODS

Both groups underwent dermatological examination, Schirmer tear test-1 (STT-1), tear meniscus height (TMH), slit-lamp biomicroscopy, interferometry (INT) and noncontact infrared meibography (NIM).

RESULTS

One third of SA dogs presented subepithelial crystalline opacities. No significant difference between groups was observed in TMH (p = 0.944) and STT-1 values (p = 0.066). INT (p = 0.016) and NIM grades (p = 0.010) were significantly higher and lower in the SA group compared to the control group, respectively. INT values decreased with age (η = 0.930), while NIM scores (η = 0.935) increased.

CONCLUSIONS

Clinical Relevance: Subepithelial crystalline opacities in SA dogs might reflect a reduced tear film quality. In the absence of standardised methods, INT and NIM proved to be noninvasive and useful methods to examine meibomian glands. Dogs with SA showed a thinner lacrimal lipid layer and more severe meibomian gland abnormalities than control dogs, which seemed to progress with age.

Examining Tear Film Dynamics Using the Novel Tear Film Imager

PURPOSE

The purpose of this study was to examine Tear Film Imager (TFI, AdOM, Israel) generated parameters across controls and dry eye (DE) subgroups and examine the changes in TFI parameters with contact lens (CL) placement.

METHODS

The retrospective study (n = 48) was conducted at the Miami Veterans Hospital. Symptoms were assessed through validated questionnaires and signs of tear function by tear break-up time and Schirmer scores. Participants were grouped as 1) healthy, 2) evaporative, 3) aqueous deficient, and 4) mixed DE based on tear function. Seventeen individuals had a baseline scan and a repeat scan following CL placement. Descriptives were compared across groups and over time.

RESULTS

The median age was 27 years, 74% self-identified as White, 45% as male, and 51% as Hispanic. Subjects in the aqueous deficiency category had lower muco-aqueous layer thickness (MALT) (2672 vs. 3084 nm) but higher lipid layer thickness (47.5 vs. 38.3 nm), lipid break-up time (4.4 vs. 2 seconds), and interblink interval (13.9 vs. 5.4 seconds) compared with the evaporative group. Subjects in the evaporative group had the highest MALT values (3084 vs. 2988, 2672, 3053 nm) compared with healthy, aqueous-deficient, and mixed groups. Symptoms were not significantly correlated with TFI parameters. CL placement significantly decreased MALT values (2869 → 2175 nm, P = 0.001).

CONCLUSIONS

The TFI provides unique information regarding the dynamic function of the tear film not captured by clinical examination. TFI generated metrics demonstrate a thinner aqueous layer in individuals with aqueous deficiency but highlight a thicker aqueous layer in those with evaporative DE.

Is Meibomian Gland Dysfunction One Disease? Heterogeneity Among Phenotypes

PURPOSE

The purpose of this study was to examine ocular surface symptoms, tear metrics, and tear cytokines by Meibomian gland dysfunction (MGD) features.

METHODS

Symptom questionnaires and an ocular surface evaluation were performed on 40 individuals with varied MGD signs (Meibomian gland [MG] plugging, eyelid vascularity, meibum quality, and MG dropout). Tear proteins were extracted off Schirmer strips and analyzed for 23 human inflammation-related proteins. Statistical analysis was performed to examine associations between dry eye metrics inflammatory proteins and MGD features.

RESULTS

The study involved 40 South Florida veterans with a mean age of 61 ± 13 years; most individuals were male (95%), White (31%), and non-Hispanic (85%). MGD features differentially related to dry eye signs. Eyelid vascularity, meibum quality, and MG dropout, but not MG plugging, correlated with higher corneal staining and lower tear production. MGD features also differentially related to tear cytokines. Eyelid vascularity most closely related to inflammation with significant correlations for interferon-gamma-γ (r = 0.36, P = 0.02), interleukin-4 (IL-4) (r = 0.43, P = 0.006), IL-17A (r = 0.42, P = 0.007), matrix metalloproteinase-2 (r = 0.39, P = 0.01), C-X-C motif chemokine ligand 5 (Regulated upon Activation, Normal T-Cell Expressed and presumably Secreted [RANTES]) (r = 0.32, P = 0.04), and tumor necrosis factor α (r = 0.36, P = 0.02). The other 3 MGD signs were less related to inflammation. Multivariable models revealed IL-4 to be most closely related to eyelid vascularity (standardized β = 0.39, P < 0.0001).

CONCLUSIONS

Eyelid vascularity was the MGD sign most closely related to inflammatory cytokines, suggesting that different MGD features may be driven by different pathophysiological mechanisms.

Safety and Efficacy of Dry Eye Intelligent Therapeutic Device in the Treatment of Meibomian Gland Dysfunction in Rabbits

PURPOSE

To assess the safety and efficacy of the dry eye intelligent therapeutic device in rabbits with meibomian gland dysfunction.

METHODS

The meibomian gland dysfunction-afflicted rabbits were subjected to treatment using the dry eye intelligent therapeutic device. Various parameters, including eyelid margin, meibomian gland opening, redness, meibomian gland area, keratoconjunctival fluorescence staining, and intraocular pressure, were examined and analyzed using an ocular surface comprehensive examination instrument, slit lamp, and tonometer at corresponding times points. Hematoxylin and eosin staining was performed to examine the mucosal epithelium and meibomian gland.

RESULTS

In this study, eyelid margin congestion and meibomian gland opening obstruction were significantly improved after 3 weeks and 4 weeks of treatment, respectively (p < .01, p < .05). The treatment group showed a significant increase in tear meniscus height after 2 weeks, 3 weeks and 4 weeks of treatment (p < .001, p < .01, p < .05). No significant changes were noted in meibomian gland area, redness, intraocular pressure, and keratoconjunctival fluorescence staining of rabbits before and after treatment. Hematoxylin and eosin staining revealed a complete structure of mucosal epithelium and meibomian gland in the treatment group and that the expansion of the blocked meibomian gland duct was reduced.

CONCLUSION

The utilization of the dry eye intelligent therapeutic device in treating meibomian gland dysfunction-afflicted rabbits exhibits potential promising safety, efficacy, and overall benefits, thereby offering a novel alternative for managing meibomian gland dysfunction patients in clinical settings.

Comparison of manual versus automated thermal lid therapy with expression for meibomian gland dysfunction in patients with dry eye disease

To compare two types of lipid expression procedures to treat dry eye disease. Standardized treatment and evaluation methods were used in patients treated with either manual thermoelectric lipid expression (MiBoFlo) or automated lipid expression (Lipiflow) of the Meibomian glands. This was a contemporaneous, non-randomized study of both treatment methods. Treatment was per the manufacturers' recommendation. The primary outcome included two types of dry eye questionnaires as well as objective analysis of ocular surface including tear break up time, Schirmer testing, Osmolarity, and fluorescein staining. Baseline characteristics analyzed included floppy lid, conjunctivochalasis and lagophthalmos. Statistical analysis was performed correcting for baseline factors such as age and co existing pathology using multivariable analysis. Both treatments improved the results of the OSDI and SPEED dry eye questionnaire results. Both treatments resulted in improvement of many objective findings including SPK, lissamine green staining and tear break up time with the MiBoFlo showing more improvement than Lipiflow. OSDI was more sensitive to improvement of symptoms than the SPEED questionnaire. Manual expression with MiBoFlo device resulted in statistically more improvement in questionnaire scores than did automated expression with Lipiflow. Negative prognostic factors for symptomatic improvement included blepharitis, autoimmune disease and ocular allergies. Thermal lid therapy along with mechanical expression of lipids from the meibomian glands successfully treats dry eye symptoms and signs. Manual therapy with MiBoFlo resulted in more subjective and objective improvement scores than automated therapy with the Lipiflow device.

Epidemiology and Risk Factors of Dry Eye Disease: Considerations for Clinical Management

Dry eye disease is a multifactorial condition characterised by tear film instability, hyperosmolarity and ocular surface inflammation. Understanding the epidemiology of dry eye disease and recognising both modifiable and non-modifiable risk factors can assist eye care practitioners in assessing, treating, and managing patients with the condition. This review considers current knowledge surrounding its incidence and prevalence, as well as associated demographic, systemic, ocular, and iatrogenic, and lifestyle-related modifiable risk factors. Population-based prevalence estimates vary according to the diagnostic criteria used to define dry eye disease, as well as severity and demographic characteristics of the population. Considering recent data and variable population demographics, conservative prevalence estimates suggest that 10-20% of the population over 40 years of age report moderate to severe symptoms and/or seek treatment for dry eye disease. Individuals with specific non-modifiable demographic risk factors may be at increased risk of developing dry eye disease. Advanced age, female sex and East Asian ethnicity have been identified as key non-modifiable demographic features predisposing individuals to dry eye disease. Systemic conditions that have been associated with an increased risk of dry eye disease include migraine, Sjögren syndrome, connective tissue disorders, mental health disorders, diabetes mellitus and androgen deficiency. Medications that may contribute to this risk include antidepressants, antihistamines, and hormone replacement therapy. Ocular and iatrogenic risk factors of dry eye disease include blepharitis, Demodex infestation, ocular surgery, blink completeness, contact lens wear, and topical ophthalmic medications. A range of modifiable lifestyle factors that can increase the risk of dry eye disease have also been identified, including low humidity environments, digital screen use, quality of sleep, diet, and eye cosmetic wear. Dry eye is a common disease affecting millions globally. Increasing knowledge regarding its associated risk factors can better prepare the eye care practitioner to successfully manage patients with this ocular surface disease.

Understanding Ocular Graft-versus-Host Disease to Facilitate an Integrated Multidisciplinary Approach

Ocular graft-versus-host disease (oGVHD) remains a challenging and potentially devastating complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although oGVHD significantly impacts the quality of life of affected survivors, it often goes unrecognized, particularly in the early stages. Targeting all providers in the HSCT community who see patients regularly and frequently for their post-allo-HSCT care, this review and opinion piece introduces the basic concepts of ocular surface pathophysiology, dissects the different stages of clinical presentation of oGVHD, explains why the current diagnostic criteria tend to capture the late disease stages, and highlights the warning signs of early disease development to facilitate prompt referral of oGVHD suspects for ocular specialist care. Along with introducing a comprehensive list of treatment options, this review emphasizes basic therapeutic strategy and options that can be safely and effectively initiated by any care provider. We believe in empowering patients as well as care providers beyond disciplinary boundaries to provide the most cohesive and integrated care in a multidisciplinary approach.

Eyelid margin disease (blepharitis and meibomian gland dysfunction): clinical review of evidence-based and emerging treatments

Blepharitis is a common ophthalmic condition with multiple etiologies and no definitive, universal treatment. The treatment modalities for managing lid margin diseases vary depending on the disease's cause, location, and severity. For anterior blepharitis, management options include eyelid hygiene with warm compresses, eyelid scrubs, baby shampoo, and over-the-counter eyelid cleansers. Topical antibiotics and antibiotic-steroid combination drops/ointments for the eye and eyelid may accompany these. For posterior blepharitis/meibomian gland dysfunction (MGD), at-home warm compress or in-office administration of heat therapy/thermal pulsation treatment that aims to clear obstruction in the meibomian glands and restore meibum secretions to maintain a healthy tear film is recommended. In addition to the above treatment strategies, various other compounds to manage lid margin diseases are in the late stages of development. This review summarizes the available treatment modalities or those in the pipeline for treating blepharitis and MGD.

BCLA CLEAR Presbyopia: Management with corneal techniques

Corneal techniques for enhancing near and intermediate vision to correct presbyopia include surgical and contact lens treatment modalities. Broad approaches used independently or in combination include correcting one eye for distant and the other for near or intermediate vision, (termed monovision or mini-monovision depending on the degree of anisometropia) and/or extending the eye's depth of focus [1]. This report reviews the evidence for the treatment profile, safety, and efficacy of the current range of corneal techniques for managing presbyopia. The visual needs and expectations of the patient, their ocular characteristics, and prior history of surgery are critical considerations for patient selection and preoperative evaluation. Contraindications to refractive surgery include unstable refraction, corneal abnormalities, inadequate corneal thickness for the proposed ablation depth, ocular and systemic co-morbidities, uncontrolled mental health issues and unrealistic patient expectations. Laser refractive options for monovision include surface/stromal ablation techniques and keratorefractive lenticule extraction. Alteration of spherical aberration and multifocal ablation profiles are the primary means for increasing ocular depth of focus, using surface and non-surface laser refractive techniques. Corneal inlays use either small aperture optics to increase depth of field or modify the anterior corneal curvature to induce corneal multifocality. In presbyopia correction by conductive keratoplasty, radiofrequency energy is applied to the mid-peripheral corneal stroma, leading to mid-peripheral corneal shrinkage and central corneal steepening. Hyperopic orthokeratology lens fitting can induce spherical aberration and correct some level of presbyopia. Postoperative management, and consideration of potential complications, varies according to technique applied and the time to restore corneal stability, but a minimum of 3 months of follow-up is recommended after corneal refractive procedures. Ongoing follow-up is important in orthokeratology and longer-term follow-up may be required in the event of late complications following corneal inlay surgery.

Demographic and lifestyle factors associated with dry eye disease in China: A cross-sectional multi-center study

PURPOSE

Associations were assessed between demographic/lifestyle factors and tear film breakup time (TBUT) defined dry eye disease (DED) in China.

METHODS

The cross-sectional study involved 50,280 subjects (54 ± 17 y) in 217 clinics (25 provinces). Data included sleep disorders; digital screen exposure; and use of cosmetics, contact lenses, and eye drops (for asthenopia). Clinical examinations included TBUT; Schirmer I test; meibomian gland plug status. TBUT-defined DED was TBUT <10 s, with TBUT ≤5 s also considered (i.e., short TBUT-type DED), either unilateral or bilateral.

RESULTS

TBUT-defined DED was present in 81.6 % overall. The highest rates were in those 71 years or older, living in the north, with chronic daily sleep disorder, or daily cosmetic application; or daily digital screen exposure for 5 years, contact lenses 4 h, or 3 months eye drops. Compared with those without TBUT-defined DED, those with TBUT-defined DED showed lower Schirmer I results and more severe meibomian gland plug status (each, P < 0.001). Independent risk factors of DED were: aging; living in the southwest; daily digital screen exposure ≥3 h; and occasional cosmetic use. Risk factors of DED TBUT ≤5 s were: living in the southwest; wearing contact lenses (>3 y); and using eye drops. Rates of unilateral and bilateral DED were comparable.

CONCLUSIONS

DED in China is more likely in the aged and those in the north/southwest. DED rates increase with digital screen exposure, and use of cosmetics, contact lenses, or eye drops for asthenopia. Unilateral DED should be treated as promptly as bilateral.

Safety and Efficacy of Topical Vitamin D in the Management of Dry Eye Disease Associated With Meibomian Gland Dysfunction: A Placebo-Controlled Double-Blind Randomized Controlled Trial

PURPOSE

The aim of this study was to investigate the safety and efficacy of topical vitamin D in the management of dry eye disease associated with meibomian gland dysfunction (MGD).

METHODS

In this randomized controlled trial, patients with symptomatic MGD were divided into 2 groups to receive topical vitamin D drops or placebo in their randomized eyes. The exclusion criteria consisted of patients with vitamin D deficiency, previous ocular surgery, and patients with ocular diseases affecting the tear film. Patients and researchers were masked to the study groups. The outcomes included the score of Dry Eye Questionnaire (DEQ) 5 and Ocular Surface Disease Index (OSDI), corneal and conjunctival staining score, tear breakup time (TBUT), Schirmer, and MG expressibility score evaluated at baseline and weeks 4 and 8.

RESULTS

Twenty-eight eyes of 28 patients were recruited in each group. In addition to the improvement of subjective parameters in both groups, there was a statistically significantly greater improvement in the vitamin D group compared with control for average scores of OSDI (13.38 ± 7.32 vs. 27.94 ± 7.49) and DEQ5 (9.67 ± 1.86 vs. 14.14 ± 2.45) at week 8 (Ps <0.001). In addition, a significant improvement in TBUT and Schirmer test was observed in both groups in weeks 4 and 8 ( P value <0.05). There was a significant difference between the treatment and control groups after 8 weeks for OSDI, DEQ5, Schirmer, TBUT, corneal fluorescein staining, and MG expressibility score ( P value <0.05).

CONCLUSIONS

The preliminary results of this randomized controlled trial suggested that use of topical vitamin D drops with a lipid vehicle could be safe and might significantly improve the symptoms and signs of dry eye associated with MGD.

Red filter meibography by smartphones in patients with meibomian gland dysfunction: a validity and reliability study

OBJECTIVE

The objective of this study is to determine the validity and reliability of the red filter meibography by smartphone compared with infrared in assessing meibomian gland drop-out.

METHODS AND ANALYSIS

An analytical cross-sectional study was done with a total of 35 subjects (68 eyes) with suspected MGD based on symptoms and lid morphological abnormalities. Meibomian glands were photographed using two smartphones (Samsung S9 and iPhone XR) on a slit-lamp with added red filter. Images were assessed subjectively using meiboscore by the two raters and drop-out percentages were assessed by ImageJ.

RESULTS

There was no agreement in meiboscore and a minimal level of agreement in drop-out percentages between red filter meibography and infrared. Inter-rater reliability showed no agreement between two raters. Intra-rater reliability demonstrated weak agreement in rater 1 and no agreement in rater 2.

CONCLUSION

Validity of the red filter meibography technique by smartphones is not yet satisfactory in evaluating drop-out. Further improvement on qualities of images must be done and research on subjective assessment was deemed necessary due to poor results of intrarater and inter-rater reliability.

The Yin and Yang of non-immune and immune responses in meibomian gland dysfunction

Meibomian gland dysfunction (MGD) is a leading cause of dry eye disease and one of the most common ophthalmic conditions encountered in eye clinics worldwide. These holocrine glands are situated in the eyelid, where they produce specialized lipids, or meibum, needed to lubricate the eye surface and slow tear film evaporation - functions which are critical to preserving high-resolution vision. MGD results in tear instability, rapid tear evaporation, changes in local microflora, and dry eye disease, amongst other pathological entities. While studies identifying the mechanisms of MGD have generally focused on gland obstruction, we now know that age is a major risk factor for MGD that is associated with abnormal cell differentiation and renewal. It is also now appreciated that immune-inflammatory disorders, such as certain autoimmune diseases and atopy, may trigger MGD, as demonstrated through a T cell-driven neutrophil response. Here, we independently discuss the underlying roles of gland and immune related factors in MGD, as well as the integration of these two distinct mechanisms into a unified perspective that may aid future studies. From this unique standpoint, we propose a revised model in which glandular dysfunction and immunopathogenic pathways are not primary versus secondary contributors in MGD, but are fluid, interactive, and dynamic, which we likened to the Yin and Yang of MGD.

Models for Meibomian gland dysfunction: In vivo and in vitro

Meibomian gland dysfunction (MGD) is a chronic abnormality of the Meibomian glands (MGs) that is recognized as the leading cause of evaporative dry eye worldwide. Despite its prevalence, however, the pathophysiology of MGD remains elusive, and effective disease management continues to be a challenge. In the past 50 years, different models have been developed to illustrate the pathophysiological nature of MGD and the underlying disease mechanisms. An understanding of these models is crucial if researchers are to select an appropriate model to address specific questions related to MGD and to develop new treatments. Here, we summarize the various models of MGD, discuss their applications and limitations, and provide perspectives for future studies in the field.

Efficacy of far infrared functional glasses in the treatment of meibomian gland dysfunction-related dry eye

Meibomian gland dysfunction (MGD)-related dry eye disease (DED) is a significant subtype of DED. In this research, we investigate the effectiveness of far infrared (FIR) functional glasses in the treatment of MGD-related DED. According to the TFO DEWS II diagnostic criteria, 61 eyes with MGD-related DED were included. All participants wore functional FIR glasses throughout the day for a period of 4 weeks and were followed up three times during the treatment. All subjects were followed up thoroughly in accordance with the DED clinical examination procedure. Ultimately, the treatment's impact was assessed. We found the Visual Analogue Scale and Ocular Surface Disease Index scores after FIR treatment were significantly lower than the baseline values (p < 0.05). Compared with the baseline, fluorescein tear breakup time and corneal fluorescein staining score after FIR treatment were significantly improved (p < 0.05). The eyelid margin signs, meibum quality, and meibomian gland expressibility after the 4-week treatment were significantly better than those at baseline (p < 0.05). We can see that wearing the FIR functional glasses significantly relieves the symptoms and signs of patients. We believe FIR therapy could be considered as a new method of MGD-related DED.

Higher incidence of meibomian gland dysfunction in postmenopausal women with primary acquired nasolacrimal duct obstruction

PURPOSE

This study aimed to investigate the incidence of meibomian gland dysfunction (MGD) in postmenopausal women with primary acquired nasolacrimal duct obstruction (PANDO) and enables ophthalmologists to pay attention to ocular surface damage before surgery.

METHODS

165 postmenopausal women with PANDO and 115 postmenopausal women with a normal lacrimal drainage system were enrolled in this prospective study. Based on the results of lacrimal duct irrigation and age, the participants were further subdivided. The incidence of different severities of MGD in different groups was calculated and analyzed by the chi-squared test.

RESULTS

The incidence of MGD in the PANDO group was 81.21%, and in the control group, it was 46.96%, which was significantly higher in the presence of PANDO (p < 0.001). The incidence of severe MGD in the complete and incomplete PANDO groups was higher than that in the control group (all p < 0.05), and no significant differences were observed between the complete and incomplete PANDO groups. The incidence of moderate MGD was significantly higher in the complete PANDO group than in the control group (p < 0.001). When age was considered an independent variable, the results revealed a significant value for patients aged < 70 years (p < 0.001).

CONCLUSIONS

Our study revealed a prodominantly high incidence of MGD in postmenopausal women with PANDO, especially in a complete PANDO or aged < 70 years. Ophthalmologists need to pay close attention to MGD in postmenopausal women with PANDO.

Leger AJ, Galor A. Living with your biome: how the bacterial microbiome impacts ocular surface health and disease

Introduction

Microbiome research has grown exponentially but the ocular surface microbiome (OSM) remains an area in need of further study. This review aims to explore its complexity, disease-related microbial changes, and immune interactions, and highlights the potential for its manipulation as a therapeutic for ocular surface diseases.

Areas Covered

We introduce the OSM by location and describe what constitutes a normal OSM. Second, we highlight aspects of the ocular immune system and discuss potential immune microbiome interactions in health and disease. Finally, we highlight how microbiome manipulation may have therapeutic potential for ocular surface diseases.

Expert Opinion

The ocular surface microbiome varies across its different regions, with a core phyla identified, but with genus variability. A few studies have linked microbiome composition to diseases like dry eye but more research is needed, including examining microbiome interactions with the host. Studies have noted that manipulating the microbiome may impact disease presentation. As such, microbiome manipulation via diet, oral and topical pre and probiotics, and hygienic measures may provide new therapeutic algorithms in ocular surface diseases.

Systemic antibiotic treatment for meibomian gland dysfunction-A systematic review and meta-analysis

PURPOSE

To review the efficacy and safety of oral doxycycline antibiotics versus macrolides in the treatment of meibomian gland dysfunction (MGD).

DESIGN

Systematic review and meta-analysis.

METHODS

We performed a systematic search of electronic databases for all peer-reviewed published studies which included clinical outcomes of oral antibiotic MGD treatment. Individual study data were extracted and evaluated in a weighted pooled analysis, including total sign and symptom scores, meibomian gland secretion score, tear break-up time (TBUT), fluorescein staining score and rate of complications.

RESULTS

Two thousand nine hundred and thirty-three studies were found, of which 54 were eligible for the systematic review, and six prospective studies were ultimately included for analysis, reporting on 563 cases from three countries. Age of affected patients ranged between 12 and 90 years. Overall, both treatment methods induced improvement in MGD signs and symptoms. In pooled analysis, macrolides were significantly superior in the total signs score (pooled standardized mean difference (SMD) -0.51, 95% confidence interval (CI): -0.99 to -0.03), meibomian gland secretion score (pooled SMD -0.25, 95%CI: [-0.48, -0.03]), TBUT (SMD -0.31, 95%CI: [-0.50, -0.13]) and fluorescein staining score (SMD -1.01, 95%CI: [-1.72, -0.29]). Moreover, while no severe complications were reported for both treatments, the macrolide group exhibited significantly less adverse events (pooled odds ratio 0.24 with a 95% CI of 0.16 to 0.34).

CONCLUSIONS

Both macrolides and tetracyclines are effective treatments for MGD. In this study, macrolides exhibited better efficacy and safety profile compared to tetracyclines.

Effects of climate factors and Demodex infestation on meibomian gland dysfunction-associated dry eye diseases

We examined the effects of climatic factors and Demodex infestations on meibomian gland dysfunction (MGD)-associated dry eye disease (DED) in a cross-sectional study. This study included 123 patients from Tianjin and Chengdu regions, and climate factors and the Air Quality Index (AQI) were recorded for one year. Ocular surface parameters and Demodex infestations were evaluated using various tests. Significant differences in all climatic factors and AQI were observed between Tianjin and Chengdu (P < 0.01), and ocular surface parameters also differed significantly between the two regions (P < 0.05). Temperature, relative humidity, and precipitation positively correlated with tear break-up time (BUT), meibum gland expressibility, and lid margin irregularity but negatively correlated with lissamine green staining scores (P < 0.05). Wind speed and atmospheric pressure positively correlated with corneal fluorescein staining and lissamine green staining but negatively correlated with BUT and lid margin irregularity (P < 0.05). AQI positively correlated with DED symptoms and corneal findings but negatively correlated with tear film stability and meibomian gland characteristics (P < 0.05). Demodex infestation was only positively correlated with meibum quality scores (P < 0.05). Our findings suggest that geographic climates influence ocular surface characteristics in MGD-associated DED, with daily precipitation potentially playing a significant role, and Demodex infestation contributes to meibum gland degeneration.

Evaluation of the Impact of Meibomian Gland Dysfunction Using a Novel Patient-Reported Outcome Instrument

Purpose: This study was intended to characterize the impact of meibomian gland dysfunction (MGD) on patients' quality of life. Methods: In this prospective, multicenter, noninterventional clinical study (NCT01979887), eligible individuals (age ≥40 years; absence of uncontrolled ocular/systemic disease) were categorized, based on composite grading of ocular symptoms, Schirmer score, and meibum quality, into (1) non-MGD, (2) mild/moderate MGD, or (3) severe MGD cohorts. The MGD Impact Questionnaire (MGD IQ), a 10-item patient-reported outcome measure, was self-administered at clinic visit on day 1, and readministered on day 22 to assess intervisit agreement regarding MGD IQ responses. Results: In total, 75 subjects were assigned to the study cohorts (25 per cohort). Across cohorts, MGD IQ item scores rose incrementally with increasing MGD severity. The severe MGD cohort experienced greater difficulty with reading and performance of leisure activities, greater time on eye care, and greater bother with eye care and eye appearance than the mild/moderate MGD cohort (all P < 0.05). Compared with the non-MGD cohort, the mild/moderate MGD cohort had greater difficulty working on computer, whereas the severe MGD cohort had greater difficulty reading, driving, and performing leisure activities, more frequent difficulty with outdoor activities, more time on eye care, and greater bother with eye care (all P < 0.05). Intervisit agreement between MGD IQ responses was fair to moderate (weighted kappa statistic 0.33‒0.58). Conclusions: Vision-related activities are negatively impacted by increasing severity of MGD. The MGD IQ instrument can help characterize disease severity and amplify the patient's voice in patient-centric clinical research. ClinicalTrials.gov NCT01979887.

Contact lens wear and follow-up and its association with signs and symptoms of meibomian gland dysfunction

INTRODUCTION

This study investigated the equivocal association between contact lens (CL) wear and meibomian gland dysfunction (MGD) by comparing the morphological, functional and subjective outcomes of CL wearers versus control, non-CL wearers. CL wearers were examined as two cohorts based on the annual attendance of follow-up visits (FLU-attended these visits, whereas non-FLU did not).

METHODS

Habitual logMAR visual acuity, invasive and non-invasive tear break-up time, Schirmer test, Efron grading scales, meibum quality score (MQS), meibum expressibility score (MES), meibomian gland (MG) loss, lid margin abnormalities and subjective dry eye (DE) symptoms were assessed.

RESULTS

Of the 128 participants, 31 were in the FLU cohort, 43 were in the non-FLU cohort and 54 were controls (mean ages: 22.2 ± 3.1, 23.0 ± 4.6 and 22.3 ± 3.5, respectively). Non-FLU CL wearers had more symptoms than controls (3.7 ± 2.4 vs. 2.3 ± 2.1, p < 0.01). Morphologically, FLU (16.9 ± 8.8%, p = 0.02) and non-FLU (18.6 ± 11.3%, p = 0.001) had more MG loss than controls (11.2 ± 6.8%). Functionally, FLU (0.6 ± 0.7, p = 0.01) and non-FLU (0.8 ± 0.9, p = 0.001) had worse MES than controls (0.2 ± 0.5). FLU and non-FLU were both associated with corneal staining (odds ratio [OR] = 3.42, 95% CI: 1.16-10.11, p = 0.03 and OR = 5.23, 95% CI: 1.89-14.48, p = 0.001, respectively) and MG loss (OR = 10.47, 95% CI: 1.14-96.29, p = 0.04 and OR = 16.63, 95% CI: 1.96-140.86, p = 0.01, respectively). Non-FLU CL wear was also associated with abnormal MQS (OR = 12.87, 95% CI: 1.12-148.41, p = 0.04), conjunctival staining (OR = 12.18, 95% CI: 3.66-40.51, p < 0.001) and lid margin telangiectasia (OR = 3.78, 95% CI: 1.55-9.21, p = 0.003). MGD was three times more prevalent in CL wearers (12%) than in controls (4%).

CONCLUSIONS

Both CL-wearing cohorts demonstrated significantly more MG abnormalities than controls though the difference was not clinically significant. Non-FLU CL wearers had more DE symptoms. Non-FLU CL wear is an independent predictor for more abnormalities than FLU CL wear, emphasising the importance of follow-ups.

Composition and diversity of meibum microbiota in meibomian gland dysfunction and the correlation with tear cytokine levels

Meibomian gland dysfunction (MGD) leads to meibum stasis and pathogenic bacteria proliferation. We determined meibum microbiota via next-generation sequencing (NGS) and examined their association with tear cytokine levels in patients with MGD. This cross-sectional study included 44 moderate-severe patients with MGD and 44 healthy controls (HCs). All volunteers underwent assessment with the ocular surface disease index questionnaire, Schirmer without anesthesia, tear break-up time, Oxford grading of ocular surface staining, and lid and meibum features. Sample collection included tears for cytokine detection and meibum for 16S rRNA NGS. No significant differences were observed in the α-diversity of patients with MGD compared with that in HCs. However, Simpson's index showed significantly decreased α-diversity for severe MGD than for moderate MGD (p = 0.045). Principal coordinate analysis showed no significant differences in β-diversity in meibum samples from patients with MGD and HCs. Patients with MGD had significantly higher relative abundances of Bacteroides (8.54% vs. 6.00%, p = 0.015) and Novosphingobium (0.14% vs. 0.004%, p = 0.012) than the HCs. Significantly higher interleukin (IL)-17A was detected in the MGD group than in the HC group, particularly for severe MGD (p = 0.008). Although Bacteroides was more abundant in the MGD group than in the HC group, it was not positively correlated with IL-17A. The relationship between core meibum microbiota and tear cytokine levels remains unclear. However, increased Bacteroides and Novosphingobium abundance may be critical in MGD pathophysiology.

Ocular Surface Evaluation in Immunoglobulin G4-Related Ophthalmic Disease

PURPOSE

To evaluate the functional and structural changes of the meibomian glands and ocular surface in immunoglobulin G4-related ophthalmic disease (IgG4-ROD) patients.

DESIGN

Cross-sectional, matched case-control comparison study.

METHODS

This study included 64 patients with biopsy-proven IgG4-ROD (aged 63.4 ± 12.2 years, 39 male) and 64 sex- and age-matched healthy controls. Patients were managed by hospitals covering the publicly funded ophthalmology service in Hong Kong. Outcome measures included anterior segment examination and keratographic and meibographic imagings.

RESULTS

A total of 64 worst-affected eyes of the 64 IgG4-ROD patients were analyzed. Corneal fluorescein staining (P = .0187), lid margin telangiectasia (P = .0360), lid-parallel conjunctival folds (P = .0112), papillae (P = .0393), meibomian gland plugging (P = .0001), meibomian gland expressibility (P = .0001), and meibum quality (P = .0001) were more significant in IgG4-ROD patients compared with healthy controls. Both upper and lower meibomian gland dropouts (P = .001 and .0003), and tear meniscus height (P = .0001) were higher in IgG4-ROD patients. Non-invasive tear break-up time (NITBUT) (P = .0166) and Schirmer test results (P = .0243) were lower in IgG4-ROD patients. Upper (r = 0.336, P = .0140) meibomian gland dropouts and NITBUT (r = -0.293, P = .0497) were positively and negatively correlated with the IgG4-ROD onset age, respectively. The number of extraocular organ involvement was negatively correlated with the Schirmer test(r = -0.341, P = .0167). Lower NITBUT was found in IgG4-ROD eyes with lacrimal gland enlargement than in IgG4-ROD eyes without lacrimal gland enlargement radiologically (P < .0001).

CONCLUSIONS

IgG4-ROD patients showed features of both aqueous tear deficiency and evaporative dry eye disease. We recommend ocular surface evaluation to all patients newly diagnosed with IgG4-ROD. Further studies are warranted to clarify the mechanism of IgG4-related dry eye disease.

Age related changes in hyaluronan expression leads to Meibomian gland dysfunction

The prevalence of dry eye disease (DED) ranges from ∼5 to 50 % and its associated symptoms decrease productivity and reduce the quality of life. Approximately 85 % of all DED cases are caused by Meibomian gland dysfunction (MGD). As humans and mice age, their Meibomian glands (MGs) undergo age-related changes resulting in age related-MGD (ARMGD). The precise cause of ARMGD remains elusive, which makes developing therapies extremely challenging. We previously demonstrated that a hyaluronan (HA)-rich matrix exists surrounding the MG, regulating MG morphogenesis and homeostasis. Herein, we investigated whether changes to the HA matrix in the MG throughout life contributes towards ARMGD, and whether altering this HA matrix can prevent ARMGD. For such, HA synthase (Has) knockout mice were aged and compared to age matched wild type (wt) mice. MG morphology, lipid production, PPARγ expression, basal cell proliferation, stem cells, presence of atrophic glands and MG dropout were analyzed at 8 weeks, 6 months, 1 year and 2 years of age and correlated with the composition of the HA matrix. We found that as mice age, there is a loss of HA expression in and surrounding the MGs of wt mice, while, in contrast, Has1-/-Has3-/- mice present a significant increase in HA expression through Has2 upregulation. At 1 year, Has1-/-Has3-/- mice present significantly enlarged MGs, compared to age-matched wt mice and compared to all adult mice. Thus, Has1-/-Has3-/- mice continue to develop new glandular tissue as they age, instead of suffering MG atrophy. At 2 years, Has1-/-Has3-/- mice continue to present significantly larger MGs compared to age-matched wt mice. Has1-/-Has3-/- mice present increased lipid production, increased PPARγ expression and an increase in the number of proliferating cells when compared to wt mice at all-time points analyzed. Taken together, our data shows that a loss of the HA matrix surrounding the MG as mice age contributes towards ARMGD, and increasing Has2 expression, and consequently HA levels, prevents ARMGD in mice.

Secondhand smoke exposure and ocular health: A systematic review

The toxicology of secondhand smoke (SHS), along with the harm of its exposure to human health, has been generally acknowledged; however, specific evidence is lacking on the association between SHS exposure and ocular health. In this systematic review (PROSPERO registration number: CRD42022247992), we included 55 original articles published by 12 May 2023, which dealt with SHS exposure and ocular disorders, such as eye irritation, conjunctivitis, dry eye diseases, uveitis, myopia, astigmatism, contact lens discomfort, age-related macular degeneration, glaucoma, and thyroid eye disease that addressed the ocular neurovascular structures of the macular, retinal nerve fiber layer, choroid, and corneal biomechanical parameters. We found compelling correlational evidence for eye irritation, conjunctivitis, and dry eye symptoms-supporting that SHS exposure was positively associated with inflammatory and allergic changes in the eyes. Yet, evidence about the associations between SHS exposure and other ocular disorders, structures, and parameters is still limited or controversial. Given the limitations of existing literature, more investigations with high quality and rigorous design are warranted to elucidate the potentially harmful effects of SHS exposure on ocular health.

Evaluation of the Tear Meniscus Using Optical Coherence Tomography in Meibomian Gland Dysfunction

INTRODUCTION

This study aimed to evaluate tear meniscus parameters in meibomian gland dysfunction (MGD) using optical coherence tomography and ImageJ software.

METHODS

We enrolled 66 eyes of 66 participants and measured tear meniscus parameters, including height, depth, turbidity, and percentage area occupied by particles (PAOP) in the meniscus in the MGD and control groups.

RESULTS

Tear meniscus turbidity and PAOP were significantly higher in the MGD group, but tear meniscus height (TMH) and depth (TMD) did not differ significantly between groups. Tear meniscus turbidity and PAOP were positively correlated with each other and ocular surface parameters, including OSDI and ocular surface staining scores.

CONCLUSION

Tear meniscus turbidity and PAOP were higher in the MGD group than in the control group; therefore, they can be used as significant non-invasive parameters in the prediction of MGD. TMH and TMD did not differ significantly between groups.

Research trends of worldwide ophthalmologic randomized controlled trials in the 21st century: A bibliometric study

Background

Randomized controlled trials (RCTs) are often considered the gold standard and the cornerstone for clinical practice. However, bibliometric studies on worldwide RCTs of ophthalmology published in the 21st century have not been reported in detail yet. This study aims to perform a bibliometric study and visualization analysis of worldwide ophthalmologic RCTs in the 21st century.

Methods

Global ophthalmologic RCTs from 2000 to 2022 were searched in the Web of Science Core Collection. The number of publications, country/region, institution, author, journal, and research hotspots of RCTs were analyzed using HistCite, VOSviewer, CiteSpace, and Excel software.

Results

2366 institutions and 90 journals from 83 countries/regions participated in the publication of 1769 global ophthalmologic RCTs, with the United States leading in the number of volumes and research field, and the Moorfields Eye Hospital contributing to the most publications. Ophthalmology received the greatest number of publications and co-citations. Jeffrey S. Heier owned the most publications and Jost B. Jonas owned the most co-citations. The knowledge foundations of global ophthalmologic RCTs were mainly retinopathy, glaucoma, dry eye disease (DED), and cataracts, and anti-vascular endothelial growth factor (VEGF) therapy (ranibizumab), topical ocular hypotensive medication, laser trabeculoplasty. Anti-VEGF therapy for age-related macular degeneration (AMD), DME (diabetic macular edema), and DED, the use of new diagnostic tools, and myopia were the hottest research highlights. Anti-VEGF therapy, prompt laser, triamcinolone, and verteporfin photodynamic therapy for AMD, DME, and CNV (choroidal neovascularization), DED, myopia, and open-angle glaucoma were the research hotspots with the longest duration. The future research hotspots might be DED and the prevention and control of myopia.

Conclusions

Overall, the number of global ophthalmologic RCTs in the 21st century was keeping growing, there was an imbalance between the regions and institutions, and more efforts are required to raise the quantity, quality, and global impact of high-quality clinical evidence in developing countries/regions.

Preoperative Treatment of Meibomian Gland Dysfunction with a Vectored Thermal Pulsation System Prior to Extended Depth of Focus IOL Implantation

INTRODUCTION

Patients implanted with a range-of-vision intraocular lens (IOL) (multifocal or extended depth of focus, EDOF) may be more susceptible to visual disturbances from poor tear film quality, and prophylactic treatment of meibomian gland dysfunction (MGD) has been recommended. The purpose was to evaluate whether vectored thermal pulsation (LipiFlow™) treatment prior to cataract surgery with a range-of-vision IOL safely improves postoperative outcomes.

METHODS

This is a prospective, randomized, open-label, crossover, multicenter study of patients with mild-to-moderate MGD and cataract. The test group underwent LipiFlow treatment prior to cataract surgery and implantation of an EDOF IOL, while the control group did not. Both groups were evaluated 3 months postoperatively, after which the control group received LipiFlow treatment (crossover). The control group was re-evaluated 4 months postoperatively.

RESULTS

A total of 121 subjects were randomized, with 117 eyes in the test group and 115 eyes in the control group. At 3 months after surgery, the test group had a significantly greater improvement from baseline in total meibomian gland score compared with the control group (P = 0.046). At 1 month after surgery, the test group had a significant decrease in corneal (P = 0.04) and conjunctival (P = 0.002) staining compared to the control group. At 3 months after surgery, the test group had significantly lower incidence of being bothered by halos compared with the control group (P = 0.019). The control group had a significantly lower incidence of being bothered by multiple or double vision compared with the test group (P = 0.016). After crossover, patients had significant improvement in vision (P = 0.03) and total meibomian gland score (P < 0.0001). No safety concerns or relevant safety findings were uncovered.

CONCLUSION

Presurgical LipiFlow treatment of patients implanted with range-of-vision IOLs improved meibomian gland function and postoperative ocular surface health. This supports guidelines recommending proactive diagnosis and management of MGD in patients with cataracts to improve patient experience.

TRIAL REGISTRATION

The study was registered on www.

CLINICALTRIALS

gov (NCT03708367).

Impact of Overnight Wear of Orthokeratology Lens on Thickness of Tear Film Lipid Layer in Children with Myopia

BACKGROUND

To elucidate the influence of overnight wear of orthokeratology (OOK) lenses on the thickness of the tear lipid layer (LLT).

METHODS

We conducted a retrospective cross-sectional study of children who visited The First Affiliated Hospital of USTC between July and September 2021. LLT and blinking dynamics were assessed. Diopters and corneal topography were also recorded.

RESULTS

The number of children enrolled in this program was 402 (804 eyes). One hundred and seventy-one children (342 eyes, 79 males and 92 females) aged 4 - 17 years (10.59 ± 2.54 years) who never wore OOK were included in the control group, while 231 children (462 eyes, 121 males and 110 females) aged 7 - 18 years (11.09 ± 2.24 years) who wore OOK for more than 1 week were included in the observation group. Compared to the control group with an LLT of 58.5 ± 18.19 nm, the OOK group exhibited a significant decrease in the LLT value to 54.42 ± 17.60 nm. In addition, the LLT in females was significantly thicker than that in males in both the control (male 54.78 ± 16.56 nm, female 61.70 ± 18.95 nm) and observation groups (male 51.88 ± 16.68 nm, female 57.21 ± 18.18 nm). It is worth noting that the influence of wearing OOK on the LLT value was only detected up to 18 months. Eighteen months later, there was almost no difference in LLT between the control and observation groups. We also noted that there was no change in LLT correlated to the surface regularity index/surface asymmetry index.

CONCLUSION

Wearing OOK can affect tear film LLT within the first 18 months after wear. More attention should be given to children wearing OOK for less than 18 months, especially males.

Recent advances in age-related meibomian gland dysfunction (ARMGD)

Meibomian glands (MGs), located within the tarsal plate of the eyelid, secrete meibum which is the lipid-rich secretion necessary for stabilizing the tear film and preventing tear evaporation. Changes in the quality and quantity of meibum produced causes MG dysfunction (MGD), the leading cause of evaporative dry eye disease (EDED). MGD is an underdiagnosed disease and it is estimated that, in the US, approximately 70 % of the population over 60 have MGD. Three forms of MGD occur based on their meibum secretion: hyposecretory, obstructive, and hypersecretory MGD. The pathophysiology of MGD remains poorly understood, however aging is the primary risk factor. With age, MGs undergo various age-related changes, including decreased acinar basal cell proliferation, hyperkeratinization, MG atrophy, and eventual MG drop-out, leading to age-related MGD (ARMGD). Additionally, studies have suggested that MGs can suffer inflammatory cell infiltration and changes innervation patterns with aging, which could also contribute towards ARMGD. This review focuses on how the aging process affects the MG, and more importantly, how age-related changes to the MG can lead to MG atrophy and MG drop-out, ultimately leading to ARMGD. This review also highlights the most recent developments in potential therapeutic interventions for ARMGD.

Efficacy of Topical Azithromycin versus Systemic Doxycycline in Treatment of Meibomian Gland Dysfunction

Background

Ocular surface disease (OSD) is a multifactorial and highly frequent problem. Inadequate or unstable tear film is the main cause, which leads to visual impairments. One of the primary causes of OSD is meibomian gland dysfunction (MGD), with a prevalence of 3.5 to 70%. The aim of this work was to compare the efficacy of azithromycin topical eye drops versus oral doxycycline in MGD individuals.

Methods

This prospective comparative cohort research was carried out on 56 patients of both sexes of any age with symptomatic MGD. Randomly, patients were classified into two equal groups: Group 1 was treated twice daily for 4 weeks with topical azithromycin 1% eye drops, while group 2 received oral doxycycline 100 mg capsules twice daily for 4 weeks.

Results

In the 1st follow-up, there was a significant difference between the studied groups in pain and discomfort degree (P value = 0.024) as group 1 showed a higher number of patients with a mild pain degree (P value = 0.013) while group 2 showed a higher number of patients with a severe pain degree (P value = 0.022). There was an insignificant difference between the studied groups in moderate pain degree and lid margin telangiectasia. Conjunctivitis, frothy discharge, and meniscus floaters were significantly higher in group 2 than in group 1 (P value = 0.013, 0.028, and 0.031, respectively). In group 1, the break-up time test was significantly higher than in group 2 (P value = 0.023). In the 2nd follow up, in group 2 only meniscus floaters were significantly higher than in group 1 (P value = 0.044), while in group 1 break-up time test was significantly higher than in group 2 (P value = 0.029). Otherwise, there is no significant difference between both the groups.

Conclusions

Meibomian gland dysfunction (MGD) could be treated effectively with oral doxycycline and topical azithromycin by improving symptoms, clinical signs, and stabilization of tear film. Moreover, the topical azithromycin group seemed to be superior over the oral doxycycline group in improving the quality of tear film in the short term, having fewer side effects, more compliance, and better tolerability.

The Effect of Oral Isotretinoin Therapy on Meibomian Gland Characteristics in Patients with Acne Vulgaris

INTRODUCTION

The aim of the study was to determine the effect of oral isotretinoin therapy on the functional and morphological condition of the anterior segment of the eye, with particular emphasis on the meibomian glands.

METHODS

Twenty-four patients (48 eyes) with a diagnosis of acne vulgaris were involved in the survey. All patients underwent a thorough ophthalmological examination at three time points: before therapy, 3 months after the start of therapy, and 1 month after the completion of isotretinoin therapy. The physical examination included the following elements: blink rate, analysis of the lid margin abnormality score (LAS), tear film break-up time (TFBUT) and Schirmer's test, meibomian gland loss (MGL), and the evaluation of the meibum quality score (MQS) and meibum expressibility score (MES). Additionally, the total score of an ocular surface disease index (OSDI) questionnaire was analysed.

RESULTS

In comparison with pretreatment values, significant increases in OSDI during and after the treatment (p = 0.003 and p = 0.004, respectively) were observed. Substantial deterioration during the treatment was observed for MGL (p < 0.0001), MQS (p < 0.001) and LAS (p < 0.0001), while an improvement in those parameters after isotretinoin cessation was observed (p = 0.006, p = 0.02 and p = 0.0003, respectively). The frequency of using artificial eye drops was positively associated with MGL during (Spearman's rank correlation coefficient (Rs) =  + 0.31; p = 0.03) and after the cessation of the therapy (Rs =  + 0.28; p = 0.04). Meibomian gland atrophy correlated significantly with MQS during (Rs =  + 0.29; p = 0.04) and after treatment (Rs =  + 0.38; p = 0.008). The decrease in TFBUT values correlated with increased LAS (Rs = - 0.31; p = 0.03) during the course of isotretinoin usage. We found no changes in Schirmer's test or blink rates.

CONCLUSION

Isotretinoin therapy leads to increased ocular complaints related to lipid tear film component dysfunction. This is due to reversible changes in meibomian gland morphology and function observed during drug usage.

Tear Film Lipid Layer Changes Following Combined Effect of Heated Eye Mask with Intense Pulsed Light Therapy for Evaporative Dry Eye: A Randomized Control Study

Background: Dry eye disease (DED) is a complex ocular surface inflammatory disorder with a multifactorial etiology. Therapies such as intense pulsed light (IPL) and heated eye mask (HEM) have been reported to improve the tear film lipid layer (TFLL) and signs and symptoms of DED. Methods: This randomized study aimed to compare the effects of IPL combined with HEM (IPL+HEM) group, IPL group, and control group in participants with evaporative DED. All participants were examined at baseline (D0), day 21 (D21), day 42 (D42), and day 84 (D84) for noninvasive tear breakup time (NITBUT), TFLL, corneal conjunctival staining (CS), meibomian gland quality (MGQ), meibomian gland expressibility (MGEx), and Ocular Surface Disease Index (OSDI). Results: The mean age of participants was IPL+HEM: 28.06 ± 3.88 years, IPL: 29.88 ± 4.68 years, and control: 28.52 ± 3.77 years. At D84, significant improvements in TFLL (p < 0.05), noninvasive tear breakup time (NITBUT) (p < 0.05), corneoconjunctival staining (CS) (p < 0.05), MGQ (p < 0.05), MGEx (p < 0.05), and OSDI (p < 0.05) were found in the IPL+HEM and IPL groups, whereas the control group had no significant improvements. Furthermore, ΔTFLL significantly correlated with ΔNITBUT (r = -0.678, p < 0.001), ΔCS (r = 0.321, p < 0.001), ΔMGQ (r = 0.669, p < 0.001), ΔMGEx (r = 0.598, p < 0.001), and ΔOSDI score (r = 0.649, p < 0.001). Conclusions: IPL therapy in combination with HEM and IPL therapy only can significantly improve the quality of TFLL and clinically reduce the sign and symptoms of evaporative DED. However, IPL therapy in combination with HEM was found to be more effective than IPL therapy alone.

Meibomian gland development: Where, when and how?

The Meibomian gland (MG) is an indispensable adnexal structure of eye that produces meibum, an important defensive component for maintaining ocular homeostasis. Normal development and maintenance of the MGs is required for ocular health since atrophic MGs and disturbances in composition and/or secretion of meibum result in major ocular pathologies, collectively termed as Meibomian gland dysfunction (MGD). Currently available therapies for MGD merely provide symptomatic relief and do not treat the underlying deficiency of the MGs. Hence, a thorough understanding of the timeline of MG development, maturation and aging is required for regenerative purposes along with signaling molecules & pathways controlling proper differentiation of MG lineage in mammalian eye. Understanding the factors that contribute to the development of MGs, developmental abnormalities of MGs, and changes in the quality & quantity of meibum with developing phases of MGs are essential for developing potential treatments for MGD. In this review, we compiled a timeline of events and the factors involved in the structural and functional development of MGs and the associated developmental defects of MGs during development, maturation and aging.

Meibomian gland dysfunction and blepharitis: A common and still unsolved ophthalmic problem

Blepharitis and meibomian gland dysfunction (MGD) are very common, usually underdiagnosed and underappreciated diseases. More than 50% of patients seeking ophthalmologic consultations have symptoms and signs indicating one or both entities. We summarize the key points of diagnosis and management of both diseases, comparing the work of Dry Eye Workshop II (2017) with the dry eye blepharitis syndrome unification theory. The impact of MGD/blepharitis on ocular surgery also is described. Although MGD and blepharitis seem to be uncurable, most of the time they can be successfully controlled. Different management options are available, but the key to success remains simple-routine eyelid hygiene and moisturizing with the use of preservative-free lubricants.

Efficacy and safety of AZR-MD-001 selenium sulfide ophthalmic ointment in adults with meibomian gland dysfunction: A vehicle-controlled, randomized clinical trial

PURPOSE

Meibomian gland dysfunction (MGD) is a chronic progressive disease with downstream effects on ocular signs and symptoms. AZR-MD-001 is a selenium sulfide ophthalmic ointment that was investigated as a potential treatment option for patients with MGD.

METHODS

A Phase 2, multi-center, double-masked, parallel group study was conducted across 29 sites, with 245 patients randomized 1:1:1 to AZR-MD-001 0.5%, AZR-MD-001 1.0% or vehicle applied to the lower eyelid, twice weekly. Patients were eligible for the trial if they presented with signs and symptoms of MGD. Co-primary efficacy endpoints were the changes from baseline in number of open glands (Meibomian Glands Yielding Liquid Secretion [MGYLS] score) and patient-reported ocular surface symptoms (Ocular Surface Disease Index [OSDI] total score) at Month 3. Efficacy outcomes were captured at Day 14, Month 1.5 and Month 3. Safety and tolerability were assessed for treatment-emergent adverse events (TEAEs).

RESULTS

AZR-MD-001 0.5% (n = 82 patients) treatment resulted in significant improvements in MGYLS score, with patients experiencing an average increase from baseline of 4.2 and 2.4 open glands secreting meibum for the drug and vehicle, respectively (p < 0.001) and from baseline a mean OSDI total score improvement of 7.3 and 3.8 for the drug and vehicle, respectively (p < 0.05). Most TEAEs were mild and transient, with 3 serious adverse events (SAEs) reported with AZR-MD-001 (none related to study drug).

CONCLUSIONS

Co-primary endpoints were met for AZR-MD-001 0.5% at Month 3, with a statistically significant improvement in the signs and symptoms of MGD. AZR-MD-001 was safe and well tolerated.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03652051, ANZCTR Registration Number: AZ201801.

Effect of Treatment with Topical Azithromycin or Oral Doxycycline on Tear Film Thickness in Patients with Meibomian Gland Dysfunction: A Randomized Controlled Trial

Purpose: This prospective, randomized, observer-masked, parallel-group study aimed to compare the effect of topical azithromycin and oral doxycycline on tear film thickness (TFT) and signs and symptoms of ocular surface disease (OSD) in patients with meibomian gland dysfunction (MGD). Methods: Patients were randomized to either receive topical azithromycin or oral doxycycline. After a baseline visit, three follow-up visits at intervals of 2 weeks were scheduled. Main outcome of the study was change in TFT as measured with ultrahigh resolution optical coherence tomography. Results: Twenty patients were included in the analysis. TFT significantly increased in both groups (P = 0.028 vs. baseline) with no difference between the groups (P = 0.096). As secondary outcomes, ocular surface disease index (OSDI) score and composite signs of OSD significantly decreased in both groups (P = 0.023 for OSDI and P = 0.016 for OSD signs vs. baseline). While eye-related adverse events (AEs) occurred more frequently in the azithromycin group, systemic AEs were more common in the doxycycline group. Conclusions: Both treatments improved signs and symptoms of OSD in patients with MGD with no difference between the groups. Due to the higher frequency of systemic side effects of doxycycline, azithromycin eye drops seem to be an alternative with comparable efficacy. Clinical Trial Registration number: NCT03162497.

Impacts of gender and age on meibomian gland in aged people using artificial intelligence

Purpose: To evaluate the effects of age and gender on meibomian gland (MG) parameters and the associations among MG parameters in aged people using a deep-learning based artificial intelligence (AI). Methods: A total of 119 subjects aged ≥60 were enrolled. Subjects completed an ocular surface disease index (OSDI) questionnaire, received ocular surface examinations including Meibography images captured by Keratograph 5M, diagnosis of meibomian gland dysfunction (MGD) and assessment of lid margin and meibum. Images were analyzed using an AI system to evaluate the MG area, density, number, height, width and tortuosity. Results: The mean age of the subjects was 71.61 ± 7.36 years. The prevalence of severe MGD and meibomian gland loss (MGL) increased with age, as well as the lid margin abnormities. Gender differences of MG morphological parameters were most significant in subjects less than 70 years old. The MG morphological parameters detected by AI system had strong relationship with the traditional manual evaluation of MGL and lid margin parameters. Lid margin abnormities were significantly correlated with MG height and MGL. OSDI was related to MGL, MG area, MG height, plugging and lipid extrusion test (LET). Male subjects, especially the ones who smoke or drink, had severe lid margin abnormities, and significantly decreased MG number, height, and area than the females. Conclusion: The AI system is a reliable and high-efficient method for evaluating MG morphology and function. MG morphological abnormities developed with age and were worse in the aging males, and smoking and drinking were risk factors.

How Can We Best Diagnose Severity Levels of Dry Eye Disease: Current Perspectives

Dry eye disease (DED) is a common ocular condition, but the diagnosis relative to other ocular conditions and the evaluation of severity of the condition has often been difficult. This challenge can be due to clinical signs and symptoms not always correlating with each other. An understanding of the various components which create the condition, as well as the diagnostic measures used to evaluate these components, is useful to the clinician working with DED patients. This review paper will discuss traditional diagnostic options, diagnostic imaging, and Advanced Point of Care testing capabilities to determine the severity level of dry eye disease more adequately.

Meandered and muddled: a systematic review on the impact of air pollution on ocular health

From the years 1970-2023, a systematic overview of the diverse consequences of particulate matter on eye health and a disease classification according to acute, chronic, and genetic are presented using the PubMed, Research Gate, Google Scholar, and Science Direct databases. Various studies on medical aspects correlate with the eye and health. However, from an application perspective, there is limited research on the ocular surface and air pollution. The main objective of the study is to uncover the relationship between eye health and air pollution, particularly particulate matter, along with other external factors acting as aggravators. The secondary goal of the work is to examine the existing models for mimicking human eyes. The study is followed by a questionnaire survey in a workshop, in which the exposure-based investigation was tagged based on their activity. This paper establishes a relationship between particulate matter and its influence on human health, leading to numerous eye diseases like dry eyes, conjunctivitis, myopia, glaucoma, and trachoma. The results of the questionnaire survey indicate that about 68% of the people working in the workshop are symptomatic with tears, blurred vision, and mood swings, while 32% of the people were asymptomatic. Although there are approaches for conducting experiments, the evaluation is not well defined; empirical and numerical solutions for particle deposition on the eye are needed. There prevails a broad gap in the arena of ocular deposition modeling.

TFOS lifestyle: Impact of societal challenges on the ocular surface

Societal factors associated with ocular surface diseases were mapped using a framework to characterize the relationship between the individual, their health and environment. The impact of the COVID-19 pandemic and mitigating factors on ocular surface diseases were considered in a systematic review. Age and sex effects were generally well-characterized for inflammatory, infectious, autoimmune and trauma-related conditions. Sex and gender, through biological, socio-economic, and cultural factors impact the prevalence and severity of disease, access to, and use of, care. Genetic factors, race, smoking and co-morbidities are generally well characterized, with interdependencies with geographical, employment and socioeconomic factors. Living and working conditions include employment, education, water and sanitation, poverty and socioeconomic class. Employment type and hobbies are associated with eye trauma and burns. Regional, global socio-economic, cultural and environmental conditions, include remoteness, geography, seasonality, availability of and access to services. Violence associated with war, acid attacks and domestic violence are associated with traumatic injuries. The impacts of conflict, pandemic and climate are exacerbated by decreased food security, access to health services and workers. Digital technology can impact diseases through physical and mental health effects and access to health information and services. The COVID-19 pandemic and related mitigating strategies are mostly associated with an increased risk of developing new or worsening existing ocular surface diseases. Societal factors impact the type and severity of ocular surface diseases, although there is considerable interdependence between factors. The overlay of the digital environment, natural disasters, conflict and the pandemic have modified access to services in some regions.

Hot towels: The bedrock of Meibomian gland dysfunction treatment - A review

BACKGROUND

Meibomian gland dysfunction (MGD) reduces quality-of-life and hinders work productivity of millions of patients, with high direct and indirect societal costs. Thickened meibum obstructs the glands and disrupts ocular surface health. Heating the eyelids to soften and express meibum from the glands can be beneficial. The most accessible method for eyelid warming uses heated, wet towels. However, the efficacy of this treatment is reliant on the methodology, and evidence-based best-practice recommendations are needed.

PURPOSE

To evaluate the literature on hot towels in MGD treatment and recommend a best-practice protocol for future research and patient treatment.

METHODS

Studies were identified through PubMed on the May 28, 2021, with the search terms: (warm* OR heat* OR thermal* OR towel OR wet towel) AND (meibomian OR MGD OR eyelid OR "dry eye" OR DED). All relevant original articles with English full-text were included.

RESULTS

The search yielded 903 results, of which 22 met the inclusion criteria. Across studies, hot towels were found to be effective at reducing ocular symptoms. However, without reheating, the temperature quickly fell below the therapeutic range, which was deemed to be between 40 °C and 47 °C. Towels heated to around 45 °C and reheated every-two minutes were most effective at increasing eyelid temperature, comparable or better than several commercially available eyelid warming devices. No adverse effects were reported in the studies.

CONCLUSION

Hot towel treatment effectively warms the eyelids and reduces ocular symptoms, but must be standardized, and towels reheated to achieve maximum benefit. Future research should assess patient satisfaction with different hot towel treatment methods that reheat or replace the towel at least every-two minutes, to establish which methods yield the greatest compliance. Guidelines or clinical recommendations that do not mention the need for regular reheating during hot towel compress treatment should be updated to include this.

Symptoms and signs of dry eye in children with Graves' ophthalmopathy

PURPOSE

The purpose of this study is to evaluate the tear secretion and ocular surface properties in children with Graves' ophthalmopathy (GO) and to compare the results with those of healthy children.

METHODS

This was a cross-sectional study. Forty-three patients with GO (Group 1) and 41 healthy children without any ocular and/or systemic disorder (Group 2) were examined clinically and underwent tests for dry eye. We performed analyses including the Ocular Surface Disease Index (OSDI) questionnaire, Schirmer's test under topical anesthesia (<5 mm was abnormal), slit-lamp biomicroscopy (corneal fluorescein staining and tear breakup time (TBUT) under blue-light illumination), and fundoscopic evaluation.

RESULTS

Dry eye symptoms and the mean OSDI score were significantly (P < 0.02) higher (15.6 ± 18.7) in patients with GO compared with controls (5.67 ± 3.6). The mean Schirmer's (basal tear secretion) tests value was significantly reduced in Group 1 (5.25 ± 3.1 mm) compared with Group 2 (17.1 ± 5.2), respectively. The difference was statistically significant (p < 0.005), suggesting inadequate tear production. The mean tear film breakup time in children was lower in patients with GO (8.3 ± 3.42 s,) compared with controls (13.2 ± 4.74 s), (P < 0.001) suggesting an unstable tear film. Decrease of corneal sensitivity (23.3%) was noted in patients with GO compared with controls. GO patients showed a significant increase of the frequency of corneal fluorescein staining (6.9%) in patients with GO compared with controls.

CONCLUSION

Patients with GO had a statistically significant higher incidence of dry eye symptoms and the increase of OSDI score. Significantly lower Schirmer's and TBUT tests results were seen in the study group when compared with the controls. These findings may indicate a tendency for dry eye in pediatric GO patients.

Meibomitis. Clinical cases

Meibomitis (M) is an inflammation of the meibomian gland (MG) with the involvement of the surrounding tissue. One of the causes of M is an obstructed outflow of fat secretion, complicated by an accompanying infection. The authors propose a new algorithm for the treatment of M (complex conservative therapy, probing of the meibomian gland with an eyelash, and dissection) and offer a classification of meibomitis, which provides a better understanding of the various forms and stages of the disease. Practical application of the proposed treatment algorithm and the classification of M are illustrated by four clinical cases, which reveal the possible causes of M, unusual forms of its manifestation, and open new possibilities of eyelash probing of the meibomian gland.

Primary cilia control cellular patterning of Meibomian glands during morphogenesis but not lipid composition

Meibomian glands (MGs) are modified sebaceous glands producing the tear film's lipids. Despite their critical role in maintaining clear vision, the mechanisms underlying MG morphogenesis in development and disease remain obscure. Cilia-mediate signals are critical for the development of skin adnexa, including sebaceous glands. Thus, we investigated the role of cilia in MG morphogenesis during development. Most cells were ciliated during early MG development, followed by cilia disassembly during differentiation. In mature glands, ciliated cells were primarily restricted to the basal layer of the proximal gland central duct. Cilia ablation in keratine14-expressing tissue disrupted the accumulation of proliferative cells at the distal tip but did not affect the overall rate of proliferation or apoptosis. Moreover, impaired cellular patterning during elongation resulted in hypertrophy of mature MGs with increased meibum volume without altering its lipid composition. Thus, cilia signaling networks provide a new platform to design therapeutic treatments for MG dysfunction.

Association between Dyslipidemia and Meibomian Gland Dysfunction: A Systematic Review and Meta-Analysis

PURPOSE

This study aimed to use meta-analysis to estimate the association between dyslipidemia and meibomian gland dysfunction.

METHODS

The following databases were searched: PubMed, Google Scholar, and Scopus. Case-control and cohort studies assessing the association between dyslipidemia and meibomian gland dysfunction were included. The association was assessed using odds ratios. Heterogeneity between studies was assessed with the χ2 statistic and degree of inconsistency. The quality of studies was assessed using the Newcastle-Ottawa Scale. The systematic review was registered on PROSPERO (ID: CRD42022347982).

RESULTS

The systematic review included three case-control and two cohort studies. The odds of hypercholesterolemia and hypertriglyceridemia in meibomian gland dysfunction were 5.45 (95% confidence interval [CI], 1.65 to 17.95) and 3.28 (95% CI, 1.25 to 8.62), respectively. The odds of elevated serum low-density lipoprotein and reduced high-density lipoprotein in meibomian gland dysfunction were 2.72 (95% CI, 1.24 to 5.98) and 1.15 (95% CI, 0.74 to 1.79), respectively. The current study's limitation is that the effects of sex, age, and meibomian gland dysfunction severity on the association between dyslipidemia and meibomian gland dysfunction were not assessed.

CONCLUSIONS

The current study suggests a significant association between dyslipidemia and meibomian gland dysfunction. This finding suggests that meibomian gland dysfunction diagnosis may call for dyslipidemia screening.

Is Corneal Subbasal Nerve Loss Associated With Meibomian Gland Loss in Inactive Mild and Moderate-to-Severe Graves' Ophthalmopathy?

PURPOSE

To evaluate meibomian gland and subbasal nerve plexus parameters in Graves' Ophthalmopathy (GO) and association of meibomian gland loss with corneal subbasal nerve plexus loss.

METHODS

Fifty-two eyes of 52 mild and moderate-to-severe GO patients and 32 eyes of 32 healthy controls were enrolled. The meibomian gland dropout area (MGDA) and meibography scores were evaluated using noncontact meibography. In vivo confocal microscopy of corneal subbasal nerve plexus were conducted. ACCMetrics was used to obtain corneal parameters.

RESULTS

Compared with healthy subjects, GO patients had worse upper and lower eyelid MGDA ( p < 0.001, for all) and upper, lower and total meibography scores ( p < 0.001, p = 0.001, and p < 0.001, respectively). Eyelid margin scores were worse in the GO group ( p < 0.001) and showed correlation with all noncontact meibography parameters ( p < 0.001 for all). All corneal subbasal nerve parameters were significantly lower in the GO group compared with the controls ( p < 0.05 for all). Subbasal nerve parameters of GO patients did not reveal a correlation with MGDA and meibography scores but showed correlations with ocular surface disease index score and Schirmer I test (r = -0.304; p = 0.042 and r = 0.336; p = 0.021, respectively).

CONCLUSION

Meibomian gland and corneal nerve loss could be observed even in the inactive phase and mild GO. The lack of a correlation between meibomian gland loss and subbasal nerve loss suggests that meibomian gland loss is not a significant additional component in the pathogenesis of subbasal nerve damage in GO. Furthermore, our study revealed new evidence regarding the use of eyelid margin score to represent meibomian gland loss in GO.

Dry Eye Disease Associated with Meibomian Gland Dysfunction: Focus on Tear Film Characteristics and the Therapeutic Landscape

Meibomian gland dysfunction (MGD) is highly prevalent and is the leading cause of evaporative dry eye disease (DED). MGD is characterized by a reduction in meibum secretion and/or a change in meibum composition that results in the disruption of the tear film lipid layer and an increase in the tear film evaporation rate. Excessive evaporation causes tear film instability, desiccation, tear hyperosmolarity, inflammation, and apoptosis of ocular surface cells, resulting in a continuous cycle of DED. The primary treatment goal for DED associated with MGD is to restore the tear film lipid layer and decrease evaporation, thereby reducing ocular signs and symptoms. The management of MGD includes home care options (eyelid hygiene, warming eye masks, ocular lubricants) and office-based treatments (manual expression, microblepharoexfoliation, thermal pulsation, intense pulsed light, intraductal probing). Topical ophthalmic prescription medications attempt to alter various factors that may contribute to DED (e.g., inflammation, bacterial growth, inadequate tear production). In this review, clinical evidence regarding available treatments and emerging therapies from randomized studies in patients with DED associated with MGD is summarized. Although some treatment modalities have been evaluated specifically for DED patients with MGD, large-scale randomized controlled trials are needed to confirm efficacy and safety in this patient population. Currently, there are no approved prescription pharmacologic treatments specifically indicated for DED associated with MGD, and those medications approved for the treatment of DED do not target the key driver of the disease (i.e., excessive evaporation). NOV03 (perfluorohexyloctane; under review with the US Food and Drug Administration) is the most advanced emerging therapy for DED associated with MGD and has demonstrated statistically significant improvements in both signs and symptoms in randomized controlled trials. Development of novel pharmacotherapies will improve therapeutic options and allow for a more individualized approach for patients with DED associated with MGD.

Meibomian Gland Dysfunction: A Route of Ocular Graft-Versus-Host Disease Progression That Drives a Vicious Cycle of Ocular Surface Inflammatory Damage

PURPOSE

To investigate the role of aggressive meibomian gland dysfunction (MGD) in the immune pathogenesis of ocular graft-vs-host disease (GVHD).

METHODS

In mice, an allogeneic GVHD model was established by transferring bone marrow (BM) and purified splenic T cells from C57BL/6J mice into irradiated C3-SW.H2b mice (BM+T). Control groups received BM only. Mice were scored clinically across the post-transplantation period. MGD severity was categorized using the degree of atrophy on harvested lids. Immune disease was analyzed using flow cytometry of tissues along with fluorescent tracking of BM cells onto the ocular surface. In humans, parameters from 57 patients with ocular GVHD presenting to the Duke Eye Center were retrospectively reviewed. MGD was categorized using the degree of atrophy on meibographs. Immune analysis was done using high-parameter flow cytometry on tear samples.

RESULTS

Compared with BM only, BM+T mice had higher systemic disease scores that correlated with tear fluid loss and eyelid edema. BM+T had higher immune cell infiltration in the ocular tissues and higher CD4+-cell cytokine expression in draining lymph nodes. BM+T mice with worse MGD scores had significantly worse corneal staining. In patients with ocular GVHD, 96% had other organs affected. Patients with ocular GVHD had abnormal parameters on dry eye testing, high matrix metalloproteinase-9 positivity (92%), and abundance of immune cells in tear samples. Ocular surface disease signs were worse in patients with higher MGD severity scores.

CONCLUSIONS

Ocular GVHD is driven by a systemic, T-cell-dependent process that causes meibomian gland damage and induces a robust form of ocular surface disease that correlates with MGD severity. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.