Management of meibomian gland dysfunction: a review

Er-Dong-Xiao-Ke decoction regulates lipid metabolism via PPARG-mediated UCP2/AMPK signaling to alleviate diabetic meibomian gland dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Meibomian gland dysfunction (MGD), complicated by type 2 diabetes, is associated with a high incidence of ocular surface disease, and no effective drug treatment exists. Diabetes mellitus (DM) MGD shows a notable disturbance in lipid metabolism. Er-Dong-Xiao-Ke decoction (EDXKD) has important functions in nourishing yin, clearing heat, and removing blood stasis, which are effective in the treatment of DM MGD.

AIM OF THE STUDY

To observe the therapeutic effect of EDXKD on DM MGD and its underlying molecular mechanism.

MATERIALS AND METHODS

After establishing a type 2 DM (T2DM)-induced MGD rat model, different doses of EDXKD and T0070907 were administered. The chemical constituents of EDXKD were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the molecular mechanism of EDXKD in treating DM MGD was predicted using network pharmacology. Lipid metabolism in DM meibomian glands (MGs) was analyzed using LC-MS/MS, and lipid biomarkers were screened and identified. Histological changes and lipid accumulation in MGs were detected by staining, and Peroxisome proliferator-activated receptor gamma (PPARG) expression in MG acinar cells was detected by immunofluorescence. The expression of lipid metabolism-related factors was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) or western blotting.

RESULTS

EDXKD reduced lipid accumulation in the MGs and improved the ocular surface index in DM MGD rats. The main active components of EDXKD had advantages in lipid regulation. Additionally, the PPARG signaling pathway was the key pathway of EDXKD in the treatment of DM MGD. Twelve lipid metabolites were biomarkers of EDXKD in the treatment of DM MGD, and glycerophospholipid metabolism was the main pathway of lipid regulation. Moreover, EDXKD improved lipid deposition in the acini and upregulated the expression of PPARG. Further, EDXKD regulated the PPARG-mediated UCP2/AMPK signaling network, inhibited lipid production, and promoted lipid transport.

CONCLUSION

EDXKD is an effective treatment for MGD in patients with T2DM. EDXKD can regulate lipids by regulating the PPARG-mediated UCP2/AMPK signaling network, as it reduced lipid accumulation in the MGs of DM MGD rats, promoted lipid metabolism, and improved MG function and ocular surface indices.

Evidence-Based Strategies for Warm Compress Therapy in Meibomian Gland Dysfunction

AIM

Despite promising results from technological therapies like intense pulsed light application, warm compress therapy is a mainstay in meibomian gland dysfunction (MGD). However, applying warm compresses (WC) to the eyelids is palliative rather than curative and not always dispensed with specific instructions. The range of eyelid warming treatments available and lack of clear directives for use creates uncertainty for patients accustomed to explicit dosage information. This report examines data from clinical studies across the past 20 years to identify effective protocols for three types of WC-hot towel, microwavable eye mask, and self-heating eye mask (EM).

METHOD

Literature search for studies on WC and MGD published between 2004 and 2023 in English was conducted. Studies wherein hot towel, microwavable EM, and self-heating EM were used in a treatment arm were included and those wherein they served only as control or were used in conjunction with another intervention were excluded. 20 resulting studies were separated into 3 groups: 5 on temperature profiles of WC, 6 with single application of WC, and 9 with repeated applications. Study methods and outcomes were tabulated, and a qualitative review was performed, attending to WC protocol and efficacy, as indicated by measures of tear film, meibomian gland health, and dry eye questionnaires.

RESULTS

Data from the aforementioned studies revealed that each method can achieve target eyelid temperature of 40 °C. A single application of WC-ranging from 5 to 20 min-can significantly improve tear quality, while repeated applications significantly relieve symptoms associated with dry eyes from MGD and, in most studies, significantly improve meibomian gland health. Hot towels, however, require frequent reheating to maintain eyelid temperatures above 40 °C, rendering them relatively ineffective in longitudinal studies. Microwavable EM retain heat well across 10 min and were found to improve tear break-up time and/or meibomian gland score. Self-heating EM have variable activation times and were typically applied for longer periods, showing benefits akin to microwavable EM in short-term studies. Studies monitoring compliance indicate greater deviation from protocol with higher application frequencies or longer-term use. Evidence suggests superior heat retention and therapeutic effects on specific contributing factors in MGD (such as Demodex) with moist-heat compress.

CONCLUSION

Considering decreased patience adherence to therapy with increased usage frequencies, and balancing needs to provide succinct instructions for various compress types, an advisable strategy is for patients to apply a moist-heat generating EM (microwavable or self-heating) to each eye for at least 10 min, prepared according to manufacturer's instructions.

Effect of low-level light therapy in individuals with dry eye disease

INTRODUCTION

Low-level light therapy (LLLT) or photobiomodulation, the application of red light to the eye, is used for the treatment of dry eye. Limited studies have investigated the efficacy of LLLT as a stand-alone treatment. The investigation aimed to evaluate the effect of LLLT on signs and symptoms of dry eye.

METHODS

Participants with mild to moderate dry eye were recruited for this three-visit study. Visits were 7 (±3) days apart and all participants received 633 nm LLLT (eye-light®) for 15 min at each visit. Clinical measures including first and average non-invasive keratograph tear break-up time (NIKBUT), tear meniscus height (TMH), meibomian gland (MG) loss for upper and lower eyelids, ocular surface disease index (OSDI) score, tear film lipid layer thickness, meibum quality score, Schirmer's test, corneal fluorescein staining and eyelid temperature for external upper (EUL) and external lower (ELL) eyelids were measured from the right eye of participants before and after treatment.

RESULTS

Thirty participants (mean [SD] age: 31.1 [9.5] years) completed the study. Treatment with LLLT resulted in significant differences in first and average NIKBUT, TMH, tear film lipid layer thickness, OSDI score, Schirmer's test, meibum quality score and eyelid temperature over time (all p < 0.05). Compared to baseline, TMH, tear film lipid layer thickness and eyelid temperature significantly increased by 0.06 mm (95% CI: 0.01-0.11), 12.9 nm (95% CI: 1.18-24.55), and 7.0°C, respectively, for both EUL (95% CI: 6.17-7.84) and ELL (95% CI: 6.17-7.73). The respective decrease in the OSDI score and Schirmer's test was 10.2 (95% CI: -15.15 to -5.26) and 4.4 mm (95% CI: -7.31 to -1.42; all p < 0.05). There was no significant difference in corneal fluorescein staining and MG loss after LLLT.

CONCLUSION

Low-level light therapy treatment significantly improved signs and symptoms of dry eye in the early phases of treatment, suggesting its efficacy for dry eye management.

The photothermal effect of intense pulsed light and LipiFlow in eyelid related ocular surface diseases: Meibomian gland dysfunction, Demodex and blepharitis

The treatment and management of ocular surface diseases have shifted towards a co-treatment approach focusing on overall ocular surface homeostasis. When treating issues related to the eye, it is essential to not only focus on the damaged or disabled areas but also consider the larger picture. Meibomian gland dysfunction (MGD), Demodex infection, and blepharitis all interact at the eyelid site and can cause damage to the ocular surface to varying degrees. Palpebral lesions disrupt the balance of ocular surface homeostasis, leading to dry eye and keratitis. Traditional treatments, such as manual physical hot compress massage, have limited effectiveness due to the structure of the eyelid. However, intense pulsed light (IPL) technology uses penetrating light energy to generate heat energy, which can eliminate inflammation of capillaries or kill Demodex. Additionally, the LipiFlow thermal effect and physical compression provide a more vital and longer-lasting therapeutic effect on MGD by excluding other primary causes of ocular surface inflammation. Therefore, personalized treatment techniques based on photothermal effects may be effective. In the future, IPL and LipiFlow may potentially dismiss immune-inflammation factors causing ocular surface disease or block the delivery of systemic immune-related diseases.

Analysis of Factors Associated with Anterior Location of Marx's Line

PURPOSE

The study aimed to investigate the factors associated with anterior location of Marx's line in ocular surface and living habits, especially in tear film.

MATERIALS AND METHODS

This cross-sectional study enlisted 483 participants with meibomian gland dysfunction, who were divided into two groups: 160 participants with mild anterior location of Marx's line and 323 participants with moderate-to-severe anterior location. Participants completed a survey of demographic characteristics (sex, age, length of visual terminal use, sleep duration, skin property), and the Ocular Surface Disease Index and Standard Patient Evaluation of Eye Dryness questionnaires. They also underwent slit-lamp examinations of the lids, and measurements of non-invasive tear break up time, tear meniscus height, fluorescein tear break up time, lipid layer thickness, partial blink rate, lid wiper epitheliopathy, and meibomian gland dropout.

RESULTS

The tear meniscus height (mild:0.21(0.18-0.25), moderate-to-severe:0.19(0.16-0.23), p = 0.004), fluorescein tear break up time(mild:3(2-4),moderate to severe:2(1-3), p = 0.000), max LLT(mild:87(62-100), moderate-to-severe:99(69-100), p = 0.04), average LLT(mild:64.5(47.5-96.75), moderate-to-severe:74(53-100), p = 0.012), min LLT(mild:52(38-75), moderate-to-severe:59(41-85), p = 0.029) differed significantly between mild and moderate-to-severe anterior location of Marx's line, and associated to the anterior location of Marx's line(r=-0.134, p = 0.03; r=-0.194, p = 0.000; r = 0.093, p = 0.041; r = 0.119, p = 0.009; r = 0.105, p = 0.022) However, no statistical significance was observed in the OSDI, SPEED, partial blink rate, non-invasive tear breakup time, lipid layer thickness, meibomian gland dropout and lid wiper epitheliopathy(p > 0.05). Meanwhile, in the demographic characteristics, statistically significant correlations were associated with skin property(r = 0.154, p = 0.001) and sleep duration(r=-0.124, p = 0.006), but not with age, sex, and the length of visual terminal use (p > 0.05).

CONCLUSIONS

Lower TMH and shorter TBUT positively correlated with anterior location of the Marx's line, and were risk factors. Meanwhile, participants with oily skin and shorter sleep duration were more likely to exhibit anterior location of Marx's line.

Sutureless Dehydrated Amniotic Membrane (Omnigen) Application Using a Specialised Bandage Contact Lens (OmniLenz) for the Treatment of Dry Eye Disease: A 6-Month Randomised Control Trial

Background and Objectives: Dry Eye Disease (DED) is a chronic condition characterised by tear film instability and ocular surface disruption, significantly impacting patients' quality of life. This study aimed to provide top-level clinical evidence for the long-term efficacy of dehydrated amniotic membrane (dAM, Omnigen®) delivered via a specialised bandage contact lens (sBCL, OmniLenz) for managing moderate-to-severe DED. Materials and Methods: This randomised controlled trial (NCT04553432) involved 93 participants with moderate-to-severe DED, randomised to receive a 1-week bilateral treatment of either dAM (17 mm diameter with 6 mm central 'window') applied under a sBCL or sBCL alone. Participants were assessed at baseline and followed up at 1, 3, and 6 months post-treatment. Outcomes included changes in symptomatology, tear film and ocular surface measurements, and in vivo confocal microscopy imaging of corneal nerve parameters and corneal dendritic cell (CDC) counts. Results: The dAM-sBCL group demonstrated a 65% reduction in OSDI scores at 6 months (p < 0.001), with 88% of participants showing improvement at 1 month. Corneal staining was significantly reduced in both groups. dAM-sBCL provided significant improvements in corneal nerve parameters at 1 month, with sustained positive trends at 3 months. Additionally, dAM-sBCL significantly reduced mature CDC counts, suggesting an anti-inflammatory effect. Conclusions: Treatment with dAM-sBCL for just 1 week significantly and rapidly improved dry eye symptoms as well as ocular surface signs for at least 3 months. It also enhanced corneal nerve health while reducing activated/mature corneal inflammatory cell numbers, presenting a safe and promising new treatment for moderate-to-severe DED.

Trans-eyelid distribution of epinastine to the conjunctiva following eyelid application in rabbits

PURPOSE

To reveal the penetration of epinastine, an anti-allergic ophthalmic agent, into the eyelid and its distribution to the conjunctiva after administration of a cream formulation on rabbit eyelid skin.

STUDY DESIGN

Experimental study.

METHODS

Rabbits were treated with 0.5% epinastine cream on hair-shaved eyelids, followed by preparation of eyelid tissue slices to determine spatial tissue distribution of epinastine by liquid chromatography-tandem mass spectrometry (LC-MS/MS) quantification using laser-microdissected tissues and desorption electrospray ionization mass spectrometry imaging (DESI-MSI). In addition, following either eyelid application of 0.5% epinastine cream or ocular instillation of 0.1% epinastine eye drops, concentration-time profiles of epinastine in the palpebral conjunctiva and bulbar conjunctiva were determined using LC-MS/MS.

RESULTS

Laser microdissection coupled with LC-MS/MS analysis detected high concentrations of epinastine around the outermost layer of the eyelid at 0.5 h post-administration that gradually diffused deeper into the eyelid and was distributed in the conjunctival layer at 8 and 24 h post-administration. Similar time-dependent drug distribution was observed in high-spatial-resolution images obtained using DESI-MSI. Epinastine concentrations in the conjunctival tissues peaked at 4-8 h after administration of 0.5% epinastine cream and then decreased slowly over 72 h post-administration. In contrast, epinastine concentrations peaked quickly and decreased sharply after epinastine eye drop administration.

CONCLUSION

After the application of epinastine cream to the eyelid skin, epinastine gradually permeated the eyelid. The compound was retained in the conjunctiva for 8-24 h post-administration, indicating that epinastine cream is a promising long-acting formulation for treating allergic conjunctivitis.

Efficacy and safety of intense pulsed light delivered by the C.STIM® for treatment of Meibomian gland dysfunction

INTRODUCTION

Intense pulsed light (IPL) appears to be a promising treatment for Meibomian gland dysfunction (MGD), the most common cause of dry eye disease. C.STIM® is a new IPL device. We report the first safety and efficacy study in clinical practice.

MATERIALS AND METHODS

Patients with moderate MGD treated with C.STIM® were included. Three IPL sessions were performed at D0, D15 and D45 with 4 shots per side (fluence of 8J/cm2). Clinical evaluation was performed at D0, D45 and M3 with several parameters: BUT, OSDI and Oxford scales, meibomian gland evaluation (morphology, quality and expressibility of meibum). The Lacrydiag® imaging device was used for objective evaluation of interferometry, meibography, tear meniscus height and NIBUT. The primary endpoint was the change in NIBUT between D0 and M3. Data collection was retrospective. Longitudinal analysis and a non-parametric linear mixed-effects model (R software) were used for statistical analysis.

RESULTS

Thirty-five patients were included. NIBUT increased significantly between D0 and M3, with a mean difference of 2.6seconds (95% CI 2.0; 3.1, P<0.001). The other parameters studied also changed significantly, except for meibography (percentage of loss and morphology) and tear meniscus height. No adverse event was noted.

CONCLUSION

C.STIM® appears safe and effective in the treatment of MGD, although a randomized controlled trial is needed to validate these results.

Perfluorohexyloctane Ophthalmic Solution: A Review in Dry Eye Disease

Perfluorohexyloctane ophthalmic solution (Miebo®) is a single-entity, water-, steroid- and preservative-free, first-in-class semifluorinated alkane that is approved in the USA for the treatment of the signs and symptoms of dry eye disease (DED). DED is often linked with meibomian gland dysfunction (MGD), which causes an excessive evaporation of tears. Perfluorohexyloctane ophthalmic solution stabilizes the lipid layer of the tear film and inhibits tear evaporation by forming a monolayer at the air-liquid interface. In the phase III GOBI and MOJAVE trials in adults with DED associated with MGD, one drop of perfluorohexyloctane ophthalmic solution instilled in each eye four times daily over 8 weeks resulted in statistically significant and clinically meaningful improvements in the signs and symptoms of DED compared with hypotonic saline (0.6%). The agent was generally well tolerated, with most ocular adverse events being mild or moderate in severity. The efficacy and tolerability of perfluorohexyloctane ophthalmic solution was sustained for up to 52 weeks in an extension study (KALAHARI). As the first and currently the only prescription treatment approved in the USA directly addressing the pathophysiology of excessive tear evaporation, perfluorohexyloctane ophthalmic solution is a valuable emerging option for the management of DED.

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.

Expression of ATP-Binding Cassette Transporter A1 (ABCA1) in Eyelid Tissues and Meibomian Gland Epithelial Cells

Purpose

To validate the adenosine triphosphate (ATP)-binding cassette transporter A1 (ABCA1) expression and distribution in human eyelid tissues and meibomian gland epithelial cells.

Methods

Meibomian gland tissues from human eyelids were isolated by collagenase A digestion and cultured in defined keratinocyte serum-free medium (DKSFM). Infrared imaging was used to analyze the general morphology of meibomian glands. Hematoxylin and eosin (H&E) staining and Oil Red O staining were used to observe the morphological structure and lipid secretion in the human meibomian gland tissues. Quantitative real-time polymerase chain reaction, western blotting, and immunostaining were used to detect the mRNA and protein expression and cytolocalization of ABCA1 in the meibomian gland tissues and cultured cells.

Results

The degree of loss of human meibomian gland tissue was related to age. Meibomian gland lipid metabolism was also associated with age. Additionally, human meibomian gland tissues express ABCA1 mRNA and protein; glandular epithelial cells express more ABCA1 mRNA and protein than acinar cells, and their expression in acinar cells decreases with differentiation. Furthermore, the expression of ABCA1 was downregulated in abnormal meibomian gland tissues. ABCA1 was mainly localized on the cell membrane in primary human meibomian gland epithelial cells (pHMGECs), whereas it was localized in the cytoplasm of immortalized human meibomian gland epithelial cells (iHMGECs). The mRNA and protein levels of ABCA1 in pHMGECs were higher than those in iHMGECs.

Conclusions

Meibomian gland tissues of the human eyelid degenerate with age. ABCA1 expression in acinar cells decreases after differentiation and plays an important role in meibomian gland metabolism.

Evaluation of Dry Eye Severity and Ocular Surface Inflammation in Patients with Autoimmune Rheumatic Diseases

PURPOSE

To evaluate dry eye severity and ocular surface inflammation in autoimmune rheumatic diseases (ARDs).

METHODS

Seventy-nine patients with ARDs were enrolled, including 26 patients with rheumatoid arthritis (RA), 33 patients with systemic lupus erythematosus (SLE), and 20 patients with primary Sjögren's syndrome (pSS). All patients underwent ocular surface evaluations, including ocular surface symptoms, signs, conjunctival impression cytology, and tear multicytokine detection. Systemic conditions, including disease duration, disease activity, and serological parameters, were also noted.

RESULTS

SLE patients had the shortest disease duration, and nearly half of them had low disease activity, while RA patients and pSS patients had a relatively long disease duration, and approximately 90% of them had moderate or high disease activity. The incidence of dry eye and the levels of the proinflammatory tear cytokines in SLE were significantly lower than those in RA and pSS. However, ocular surface squamous metaplasia was more severe in SLE and pSS than in RA. Dry eye severity in all ARD patients was shown to be independent of disease activity, while Nelson's grades were positively correlated with disease duration in RA patients. Disease-related serological parameters were associated with tear proinflammatory cytokines in all ARD patients.

CONCLUSIONS

Variable degrees of dry eye and immune-mediated ocular surface inflammation persist in different ARD patients. In addition to a well-known association between dry eye and pSS, dry eye is also commonly observed in SLE and RA patients. Therefore, there is a definite need for regular ophthalmologic evaluations and topical medications in all patients with ARDs.

Hypochlorous acid hygiene solution in patients affected by blepharitis: a prospective randomised study

BACKGROUND/AIMS

To investigate the clinical outcomes and antimicrobial activity of an hypochlorous acid hygiene solution compared with hyaluronic acid wipes for blepharitis treatment in patients with dry eye disease (DED).

METHODS

This study involved 48 eyes of 48 patients affected by blepharitis with mild to moderate DED. 24 patients were treated with a hypochlorous acid hygiene solution (HOCL group) and 24 patients were treated with hyaluronic acid wipes (HYAL group) for a period of 4 weeks. The following clinical outcomes were assessed before (V0) and after the treatment period (V1): non-invasive keratograph break up time (NIK-BUT), tear film BUT (TF-BUT) tear meniscus height (TMH), Keratograph meibography, Meibomian Gland Yield Secretion Score (MGYSS), Corneal Staining Score (CSS), Schirmer test I, Keratograph conjunctival redness score and Ocular Surface Disease Index (OSDI). Moreover, microbiological analysis of upper and lower eyelid margins was performed at V0 both before and 5 min after treatment.

RESULTS

After 1-month NIK-BUT and TF-BUT significantly increased in HOCL group, while they did not show a statistically significant difference in HYAL group compared with baseline. OSDI, TMH and MGYSS showed a significant difference in both groups, while Schirmer test, meibography, CSS and conjunctival redness score did not significantly change in both groups. Bacterial load showed a significant reduction in both groups, more pronounced in HOCL group compared with HYAL group.

CONCLUSIONS

Hypochlorous acid hygiene solution can be securely employed in blepharitis treatment considering the satisfying clinical outcomes and antimicrobial activity compared with hyaluronic acid wipes.

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.

Comparison Between Optimal Pulsed Technology and Meibomian Gland Massage Treatment for Contact Lens-Related Meibomian Gland Dysfunction

Objective: The purpose of this study was to compare the effectiveness of optimal pulsed technology (OPT) and meibomian gland massage (MGM) in alleviating the signs and symptoms of contact lens-related meibomian gland dysfunction (CL-MGD). Methods: This prospective, randomized, controlled study included 90 patients (180 eyes) diagnosed with CL-MGD and were assigned to the OPT group (n = 60 eyes), MGM group (n = 60 eyes), and control group (n = 60 eyes). All participants were examined at baseline (D0), day 21 (D21), and day 42 (D42) for the ocular surface disease index (OSDI), noninvasive tear break-up time (NITBUT), noninvasive tear meniscus height (NITMH), meibomian gland score (MGS), meibomian gland score (MGYSS), best-corrected visual acuity, and intraocular pressure. Results: The OSDI scores and NITBUT improved after treatment in all the three groups. The OSDI scores in OPT and MGM groups were significantly lower compared with that in the control group at D21 and further decreased at D42. The NITBUT in OPT and MGM groups increased compared with the control group at D21 and further increased at D42, and the NITBUT in OPT group increased compared with the MGM group at D21 and D42. The MGYSS both improved after treatment in the OPT and MGM groups, The MGYSS in OPT and MGM groups decreased compared with the control group at D21 and further decreased at D42, and the MGYSS in the OPT group decreased compared with the MGM group at D21 and D42. The NITMH and MGS had no differences after treatment. Conclusions: Results imply that OPT or MGM treatment can be safely used to relieve symptoms of CL-MGD. In addition, OPT treatment was found to be more effective in improving the general stability of the tear-film in CL-MGD.

Antibiotic Delivery System for Treating Bacteria-Induced Anterior Blepharitis

The eyelid-related disease of blepharitis remains a tricky ocular disorder and affects patient compliance. However, there is no available and effective treatment, making it extremely challenging. Herein, an antibacterial system based on antibiotic delivery was developed and applied in a blepharitis model induced by bacteria. The antibacterial tests against Staphylococcus aureus both in vitro and in vivo demonstrated that the system shows a favorable bactericidal effect. Then, histological evaluation indicated that the system shows both antibacterial and anti-inflammatory effects. This facile design provided an effective ocular infection management, which displays a promising prospect while addressing other complex ocular disorders.

Meibomian Gland Dysfunction Is Associated with Low Levels of Immunoglobulin Chains and Cystatin-SN

Meibomian gland dysfunction (MGD) is a highly prevalent condition and the most common cause of evaporative dry eye disease. Studying the proteome of MGD can result in important advances in the management of the condition. Here, we collected tear film samples from treatment naïve patients with MGD (n = 10) and age-matched controls (n = 11) with Schirmer filtration paper. The samples were analyzed with label-free quantification nano liquid chromatography-tandem mass spectrometry. The proteins were considered differentially expressed if p < 0.05. A total of 88 proteins were significantly regulated. The largest change was observed in cystatin-SN, which was downregulated in MGD and correlated negatively with tear meniscus height. The downregulation of cystatin-SN was confirmed with targeted mass spectrometry by single reaction monitoring (SRM). Eighteen immunoglobulin components involved in B cell activation, phagocytosis, and complement activation were downregulated in MGD including Ig alpha-1 chain C region, immunoglobulin J chain, immunoglobulin heavy variable 3-15, and Ig mu chain C region. The changes in cystatin-SN and immunoglobulin chains are likely to result from the inflammatory changes related to tear film evaporation, and future studies may assess their association with the meibum quality.

Living with Dry Eye Disease and its Effects on Quality of Life: Patient, Optometrist, and Ophthalmologist Perspectives

Dry eye disease is a very common condition, especially among aging women. People often think of it as a very mild and non-harmful issue, but the reality is that it has a huge deleterious effect on patients' quality of life. Most publications usually focus on the scientific aspects of this pathology: its epidemiology, diagnosis, or management. However, in this article we highlight the patient's perspective and the challenges of living with dry eye disease. With prior informed consent, we interviewed a patient whose life has drastically changed since she first got the diagnosis. We also asked healthcare professionals based in Miami who were involved in this patient's care for their opinions. We hope that the messages and commentaries resonate with patients and physicians involved in the care of dry eye disease worldwide.

Association of Treatment Duration and Clinical Outcomes in Dry Eye Treatment with Sutureless Cryopreserved Amniotic Membrane

Background

While sutureless, cryopreserved amniotic membrane (cAM) has been shown to significantly improve signs and symptoms of dry eye disease (DED), no studies have assessed the association of cAM treatment duration to the differential response in clinical outcomes.

Methods

A multi-center, retrospective study was conducted on patients with moderate-to-severe DED who were treated with self-retained cAM (Prokera® Slim) for 2 to 7 days. The primary outcome measure was DEWS severity score assessed at 1 week, 1 month, and 3 months. Secondary outcome measures included ocular discomfort, visual symptoms, corneal staining, and visual acuity.

Results

A total of 89 eyes (77 patients) with moderate-to-severe DED (DEWS severity 3.24 ± 0.56) received treatment with self-retained cAM for 2 days (n = 10), 3 days (n = 15), 4 days (n = 12), 5 days (n = 19), 6 days (n = 6), or 7 days (n = 27). DEWS scores significantly improved at 1 week, 1 month, and 3 months for all treatment duration groups, with no significant difference observed between groups at any timepoint. In addition to an improvement in DEWS severity scores, those receiving cAM treatment for 2 days demonstrated a significant improvement in corneal staining, visual symptoms, and ocular discomfort at 1 week, 1 month, and 3 months.

Conclusion

This retrospective study suggests that a single placement of self-retained cAM for 2 days can significantly improve signs and symptoms of DED with a lasting benefit observed for up to 3 months.

Toxicological effects of ocular acrolein exposure to eyelids in rabbits in vivo

Acrolein is a highly reactive volatile toxic chemical that injures the eyes and many organs. It has been used in wars and terrorism for wounding masses on multiple occasions and is readily accessible commercially. Our earlier studies revealed acrolein's toxicity to the cornea and witnessed damage to other ocular tissues. Eyelids play a vital role in keeping eyes mobile, moist, lubricated, and functional utilizing a range of diverse lipids produced by the Meibomian glands located in the upper and lower eyelids. This study sought to investigate acrolein's toxicity to eyelid tissues by studying the expression of inflammatory and lipid markers in rabbit eyes in vivo utilizing our reported vapor-cap model. The study was approved by the institutional animal care and use committees and followed ARVO guidelines. Twelve New Zealand White Rabbits were divided into 3 groups: Naïve (group 1), 1-min acrolein exposure (group 2), or 3-min acrolein exposure (group 3). The toxicological effects of acrolein on ocular health in live animals were monitored with regular clinical eye exams and intraocular pressure measurements and eyelid tissues post-euthanasia were subjected to H&E and Masson's trichrome histology and qRT-PCR analysis. Clinical eye examinations witnessed severely swollen eyelids, abnormal ocular discharge, chemosis, and elevated intraocular pressure (p < 0.001) in acrolein-exposed eyes. Histological studies supported clinical findings and exhibited noticeable changes in eyelid tissue morphology. Gene expression studies exhibited significantly increased expression of inflammatory and lipid mediators (LOX, PAF, Cox-2, and LTB4; p < 0.001) in acrolein-exposed eyelid tissues compared to naïve eyelid tissues. The results suggest that acrolein exposure to the eyes causes acute damage to eyelids by altering inflammatory and lipid mediators in vivo.

Dysregulation of Lipid Metabolism in Aging Meibomian Glands and Its Molecular Markers

The main function of exocrine Meibomian glands (MGs) is to produce a lipid-rich secretion called meibum which plays a critical role in maintaining the ocular surface homeostasis of humans and most mammals. The chemical composition of meibum, and its quantity produced by MGs, largely determine whether it can fulfill its role successfully. Aging was frequently associated with the onset of various MG-related pathologies. The goal of this study was to determine how aging affects the chemical composition and quantity of meibum in mice, and identify possible molecular markers of aging. Unbiased, untargeted and targeted lipidomic evaluation of mouse MG lipids was conducted using liquid chromatography-high-resolution mass spectrometry, and the results were analyzed using Principal Component, Orthogonal Projections to Latent Structures Discriminant, and Partial Least Square Discriminant Analyses. We found that aging leads to dysregulation of lipid metabolism in MGs, changing the ratios of major classes of MG lipids (such as wax esters, triacylglycerols, and phospholipids) in a progressive manner. Several lipid species that belong to these groups of MG lipids are proposed as clear markers of aging in a mouse model.

Aquaporin 5 in the eye: Expression, function, and roles in ocular diseases

As a water channel protein, aquaporin 5 (AQP5) is essential for the maintenance of the normal physiological functions of ocular tissues. This review provides an overview of the expression and function of AQP5 in the eye and discusses their role in related eye diseases. Although AQP5 plays a vital role in ocular functions, such as maintaining corneal and lens transparency, regulating water movement, and maintaining homeostasis, some of its functions in ocular tissues are still unclear. Based on the key role of AQP5 in eye function, this review suggests that in the future, eye diseases may be treated by regulating the expression of aquaporin.

Meibomian gland stem/progenitor cells: The hunt for gland renewal

Meibomian glands (MGs) secrete lipid (meibum) onto the ocular surface to form the outermost layer of the tear film. Proper meibum secretion is essential for stabilizing the tear film, reducing aqueous tear evaporation, and maintaining the homeostasis of the ocular surface. Atrophy of MG as occurs with aging, leads to reduction of meibum secretion, loss of ocular surface homeostasis and evaporative dry eye disease (EDED). Since MGs are holocrine glands, secretion of meibum requires continuous self-renewal of lipid-secreting acinar meibocytes by stem/progenitor cells, whose proliferative potential is dramatically reduced with age leading to MG atrophy and an age-related meibomian gland dysfunction (ARMGD). Understanding the cellular and molecular mechanisms regulating meibocyte stem/progenitor cell maintenance and renewal may provide novel approaches to regenerating MG and treating EDED. Towards that end, recent label retaining cell and lineage-tracing experiments as well as knock-out transgenic mouse studies have begun to identify the location and identities of meibocyte progenitor cells and potential growth and transcription factors that may regulate meibocyte renewal. In addition, recent reports have shown that ARMGD may be reversed by novel therapeutics in mice. Herein, we discuss our current understanding of meibocyte stem/progenitor cells and the hunt for gland renewal.

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.

Comparison of Light-Based Devices in the Treatment of Meibomian Gland Dysfunction

PURPOSE

To compare different light-based devices, namely, intense pulsed light (IPL) and IPL with low-level light therapy (LLLT), in the treatment of meibomian gland dysfunction (MGD).

METHODS

This was a prospective, observational study that included patients with MGD. Group 1 included 58 eyes treated with IPL (eye-light®, Espansione Marketing S.p.A., Bologna, Italy), followed by LLLT (my-mask®, Espansione Marketing S.p.A., Bologna, Italy); Group 2 included 60 eyes treated with IPL (E>Eye®, E-Swin, Houdan, France); and Group 3 included 58 eyes treated with IPL (Thermaeye Plus®, OptiMed, Sydney, Australia). The presence of symptoms (Ocular Surface Disease Index (OSDI)) and ocular surface changes were evaluated at baseline, three weeks, and six months after treatment.

RESULTS

At week three, there was an improvement in the OSDI in all groups (p<0.001), without differences among them (p=0.339). The lipid layer thickness (LLT) increased in Groups 1 and 2 (p<0.001), with a similar variation (p=0.144). Patients with superior OSDI and lower LLT at baseline had the greatest improvement in the respective parameters (p<0.001). The basal tear flow increased in Group 1 (p=0.012). Corneal staining (CS) significantly decreased in Groups 2 (p<0.001) and 3 (p<0.001). At six months, compared to three weeks, there was further improvement in the OSDI (p<0.001) and the LLT (p=0.007), in Group 1, and an increase in the presence of CS in Group 3 (p=0.011).

CONCLUSION

IPL treatment led to a sustained decrease in patients' symptoms, even after six months. Different IPL devices seem to have different beneficial effects. Adding LLLT to IPL appears to have an additional long-term beneficial effect as well as positive effects on the lacrimal gland.

The Multifold Etiologies of Limbal Stem Cell Deficiency: A Comprehensive Review on the Etiologies and Additional Treatment Options for Limbal Stem Cell Deficiency

Given the various ocular manifestations of limbal stem cell insufficiency, an awareness of the genetic, acquired, and immunological causes and associated additional treatments of limbal stem cell deficiency (LSCD) is essential for providers. We performed a comprehensive review of the literature on the various etiologies and specific therapies for LSCD. The resources utilized in this review included Medline (PubMed), Embase, and Google Scholar. All English-language articles and case reports published from November 1986 through to October 2022 were reviewed in this study. There were collectively 99 articles on these topics. No other exclusion criteria were applied. Depending on the etiology, ocular manifestations of limbal stem cell deficiency range from dry eye syndrome and redness to more severe outcomes, including corneal ulceration, ocular surface failure, and vision loss. Identifying the source of damage for LSCD is critical in the treatment process, given that therapy may extend beyond the scope of the standard protocol, including artificial tears, refractive surgery, and allogeneic stem cell transplants. This comprehensive review of the literature demonstrates the various genetic, acquired, and immunological causes of LSCD and the spectrum of supplemental therapies available.

Rosacea Meibomian Gland Dysfunction Posterior Blepharitis May Be a Marker for Earlier Associated Dyslipidaemia and Inflammation Detection and Treatment with Statins

Posterior blepharitis and dry eye are common disorders with meibomian gland dysfunction (MGD), a principal driver of their pathophysiology. Meibomian gland dysfunction is increasingly prevalent in older populations with contributory hormonal imbalances. The abnormal meibum in MGD has been documented to have an excess of cholesterol with a resultant disruption of the lipid layer of the tear film. This leads to tear film instability due to the inadequate trapping of the aqueous portion of the tear film with resultant evaporative dry eye. Significant morbidity may follow MGD with ocular surface inflammation disrupting both social and work function. Rosacea is a common chronic inflammatory condition of the central face but can have ocular and systemic inflammatory associations. It is especially prevalent in North European populations and can have onset at any age, but commonly presents between thirty and fifty years of age. In ocular rosacea, MGD is a recognised manifestation as is dyslipidaemia. Ocular rosacea can predate cutaneous disease. As yet, there is no directly reported evidence of the efficacy of the early identification and treatment of ocular rosacea with associated dyslipidaemia and systemic inflammation. We posit that MGD in ocular rosacea sufferers may be a marker for dysregulated cholesterol synthesis and inflammation, and that statins maybe a potential therapy. This article introduces potential strategies to utilise ocular rosacea MGD as a possible marker for ophthalmologists, cardiologists, and primary healthcare physicians to treat rosacea-associated dyslipidaemia and systemic inflammation. This could aid in overall cardiovascular morbidity and mortality control for rosacea sufferers, potentially at an earlier age, while also addressing their tear film de-stabilisation through cholesterol lowering and inflammation reduction.

A deep learning model established for evaluating lid margin signs with colour anterior segment photography

OBJECTIVES

To evaluate the feasibility of applying a deep learning model to identify lid margin signs from colour anterior segment photography.

METHODS

We collected a total of 832 colour anterior segment photographs from 428 dry eye patients. Eight lid margin signs were labelled by human ophthalmologists. Eight deep learning models were constructed based on VGGNet-13 and trained to identify lid margin signs. Sensitivity, specificity, receiver operative characteristic (ROC) curves and area under the curve (AUC) were applied to evaluate the models.

RESULTS

The AUC for rounding of posterior lid margin was 0.979 and was 0.977 and 0.980 for lid margin irregularity and vascularization. For hyperkeratinization, the AUC was 0.964. The AUCs for meibomian gland orifice (MGO) retroplacement and plugging were 0.963 and 0.968. For the mucocutaneous junction (MCJ) anteroplacement and retroplacement model, the AUCs were 0.950 and 0.978. The sensitivity and specificity for rounding of posterior lid margin were 0.974 and 0.921. For irregularity, the sensitivity and specificity were 0.930 and 0.938, and those for vascularization were 0.923 and 0.961. The hyperkeratinization model achieved a sensitivity and specificity of 0.889 and 0.948. The model identifying MGO plugging and retroplacement achieved a sensitivity of 0.979 and 0.909 with a specificity of 0.867 and 0.967. The sensitivity of MCJ anteroplacement and retroplacement were 0.875/0.969, with a specificity of 0.966/0.888.

CONCLUSIONS

The deep learning model could identify lid margin signs with high sensitivity and specificity. The study provided the potentiality of applying artificial intelligence in lid margin evaluation to assist dry eye decision-making.

Pulsed Oral Azithromycin vs 6-Week Oral Doxycycline for Moderate to Severe Meibomian Gland Dysfunction: A Randomized Clinical Trial

Importance

The treatment of moderate to severe meibomian gland dysfunction (MGD) with oral doxycycline requires a 6-week course of treatment and has frequent adverse effects (AEs), which may be associated with poor compliance.

Objective

To determine if the AEs of a 3-week course of oral azithromycin were equivalent to the AEs of a 6-week course of oral doxycycline.

Design, Setting, and Participants

This double-masked randomized clinical trial was conducted at a referral center in Thailand from September 2018 to May 2022. Participants with moderate to severe MGD judged unresponsive to conservative management were included.

Interventions

Patients were randomized 1:1 to receive oral azithromycin (1 g once per week for 3 weeks) or oral doxycycline (200 mg daily for 6 weeks).

Main Outcomes and Measures

After initiating therapy, the study team assessed the total MGD score and Ocular Surface Disease Index (OSDI) score at the initial visit, at 6 weeks, and at 8 weeks, and assessed AEs at 6 weeks and 8 weeks. The prespecified equivalence margins for MGD score and OSDI score were set at ±2 and ±9, respectively.

Results

A total of 137 eyes from 137 patients were randomized into groups, 68 eyes in the azithromycin group and 69 eyes in the doxycycline group (female, 66.4%; mean age, 62.0 [SD, 15.1] years). The adjusted mean difference of total MGD scores between groups at week 6 and week 8 were -0.33 (95% CI, -1.70 to 1.03; P for equivalence = .01) and 0.13 (95% CI, -1.59 to 1.84; P for equivalence = .02), respectively. The adjusted mean difference of OSDI between groups score at week 6 and week 8 was -1.20 (95% CI, -5.31 to 2.91; P for equivalence  < .001) and -1.59 (95% CI, -5.73 to 2.55; P for equivalence  < .001), respectively. In addition, patients treated with azithromycin had fewer gastrointestinal AEs (4.4% vs 15.9%; risk difference, 11.5%; 95% CI 1.6%-21.4%; P = .03).

Conclusions and Relevance

These data support an equivalency of effects of azithromycin as compared with doxycycline for MGD score and OSDI score at both follow-up times. The study did not show more gastrointestinal AEs in the azithromycin group. The reduced dosing and potentially fewer gastrointestinal AEs associated with azithromycin support its use as an alternative to doxycycline for at least 6 weeks.

Trial Registration

ThaiClinicalTrials.org Identifier: TCTR20180810001.

Ocular Surface Changes in Treatment-Naive Thyroid Eye Disease

OBJECTIVE

To investigate the association of meibomian gland dysfunction (MGD) and ocular surface exposure with tear film instability in untreated thyroid eye disease (TED) patients.

METHODS

A cross-sectional study of TED patients from September 2020 to September 2022 was conducted. Ocular surface parameters included ocular surface disease index (OSDI), tear meniscus height (TMH), non-invasive tear break-up time (NITBUT), partial blinking rate, lipid layer thickness (LLT), meibomian gland dropout (meiboscore), Schirmer's test, and corneal punctate epithelial erosions (PEE). Ocular surface exposure was assessed by the margin reflex distances of the upper and lower eyelid (MRD1 and MRD2), the amount of exophthalmos, lateral flare, and lagophthalmos.

RESULTS

In total, 152 eyes from 76 TED patients (64 females and 12 males, age 42.99 ± 12.28 years) and 93 eyes from 61 healthy controls (51 females and 10 males, age 43.52 ± 17.93 years) were examined. Compared with control eyes, TED eyes had higher OSDI, TMH, LLT, and PEE; shorter NITBUT; and worse meiboscore (all p < 0.05). They also had larger amounts of exophthalmos, longer MRD1, more lateral flare, and lagophthalmos. Multivariate analysis identified an association of the tear film instability with lagophthalmos (β = -1.13, 95%CI: -2.08, -0.18) and severe MGD in the lower eyelid (β = -5.01, 95%CI = -7.59, -2.43).

CONCLUSIONS

Dry eye in TED is mainly manifested as evaporative dry eye disease. Severe lower eyelid MGD and worse lagophthalmos were significantly associated with tear film instability in treatment-naive TED patients.

The inhibition of p38 MAPK blocked inflammation to restore the functions of rat meibomian gland epithelial cells

Meibomian glands (MGs) are vital for ocular surface health. However, the roles of inflammation in the progression of meibomian gland dysfunction (MGD) are largely unknown. In this study, the roles of the inflammation factor interleukin-1β (IL-1β) via the p38 mitogen-activated protein kinases (MAPK) signaling pathway on rat meibomian gland epithelial cells (RMGECs) were explored. Eyelids from adult rat mice at 2 months and 2 years of age were stained with specific antibodies against IL-1β to identify inflammation levels. RMGECs were exposed to IL-1β and/or SB203580, a specific inhibitor of p38 MAPK signaling pathway, for 3 days. Cell proliferation, keratinization, lipid accumulation, and matrix metalloproteinases 9 (MMP9) expression were evaluated by MTT assay, polymerase chain reaction (PCR), immunofluorescence staining, apoptosis assay, lipid staining, and Western blot analyses. We found that IL-1β was significantly higher in the terminal ducts of MGs in rats with age-related MGD than in young rats. IL-1β inhibited cell proliferation, suppressed lipid accumulation and peroxisome proliferator activator receptor γ (PPARγ) expression, and promoted apoptosis while activating the p38 MAPK signaling pathway. Cytokeratin 1 (CK1), a marker for complete keratinization, and MMP9 in RMGECs were also up-regulated by IL-1β. SB203580 effectively diminished the effects of IL-1β on differentiation, keratinization, and MMP9 expression by blocking IL-1β-induced p38 MAPK activation, although it also inhibited cell proliferation. The inhibition of the p38 MAPK signaling pathway blocked IL-1β-induced differentiation reduction, hyperkeratinization, and MMP9 overexpression of RMGECs, which provides a potential therapy for MGD.

Efficacy of vector thermal pulsation treatment in reducing postcataract surgery dry eye disease in patients affected by meibomian gland dysfunction

PURPOSE

To evaluate the effect of a single LipiFlow vector thermal pulsation treatment performed before cataract surgery in reducing signs and symptoms of postoperative dry eye disease (DED) in patients with mild-moderate meibomian gland dysfunction (MGD).

SETTING

Eye Clinic, Careggi Hospital, University of Florence, Florence, Italy.

DESIGN

Prospective unmasked randomized controlled clinical trial.

METHODS

This study included patients affected by age-related cataract and mild-moderate MGD, who were randomized into 2 groups: (1) a single LipiFlow treatment performed at 5 preoperative weeks and (2) warm compresses and eyelid massages twice a day for 1 preoperative month (control group). Noninvasive break-up time (NI-BUT), Schirmer test, Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire, and MG functionality parameters were evaluated at visit 0 (5 preoperative weeks), visit 1 (1 preoperative week), and visit 2 (1 postoperative month). Confocal microscopy of the MG of lower eyelids was performed at visit 0 and visit 2.

RESULTS

A total of 46 patients (46 eyes) were enrolled. In the LipiFlow group (n = 23), NI-BUT, SPEED questionnaire, and MG functionality parameters significantly improved at visit 1 ( P < .05) and visit 2 ( P < .05) compared with baseline and remained stable postoperatively. In the control group (n = 23), they did not significantly improve after treatment, while worsened postoperatively. Moreover, the changes in all parameters from baseline were significantly different between the 2 groups. Confocal microscopy imaging highlighted lower postoperative MG alterations in the LipiFlow group.

CONCLUSIONS

A single preoperative LipiFlow treatment was effective in preventing postcataract surgery DED in patients with mild-moderate MGD. Postoperatively, treated patients displayed a better ocular surface status compared with warm compresses.

Impact of Thermal Pulsation System Therapy on Pre-Operative Intraocular Lens Calculations before Cataract Surgery in Patients with Meibomian Gland Disfunction

In patients with eye surface disorders such as dry eye syndrome or Meibomian gland dysfunction (MGD) it is necessary to improve the tear film condition in order to obtain visual system measurements before cataract surgery. The aim of the project was to analyze the Thermal Pulsation System (TPS) impact on the visual system parameters used in cataract surgery qualification. The study included six patients (11 eyes) with MGD diagnosis. All patients were treated with TPS. The obtained results were compared and used to calculate the power and type of the intraocular lens (IOL). As a treatment result, the power of astigmatism has changed in 64% of the eyes. Planned surgical treatment type has changed in 27% of cases. TPS also affected the cylinder axis in three eyes, which was 27% of cases. Based on the calculations, power of the recommended IOL has changed in five eyes (46%). Stabilization of visual system parameters after TPS allowed to improve the accuracy of the results. It also ensured the proper astigmatism treating method during cataract surgery and allowed selection of the proper IOL power and type.

High-fat intake reshapes the circadian transcriptome profile and metabolism in murine meibomian glands

Background

Nutritional and food components reshape the peripheral clock and metabolism. However, whether food challenges affect the circadian clock and metabolism of meibomian glands (MGs) has not been fully explored. This study was designed to analyze alterations in the rhythmic transcriptome and metabolism of MGs of murine fed a balanced diet or a high-fat diet (HFD).

Methods

Male C57BL/6J mice were maintained on a 12/12 h light/dark cycle and fed ad libitum on normal chow (NC) or HFD for 4 weeks. MGs were collected from sacrificed animals at 3-h intervals throughout a 24-h circadian cycle. The circadian transcriptome of MGs was analyzed via bioinformatics approaches using high-throughput RNA sequencing (RNA-seq). In addition, circadian oscillations of lipid components in MGs were analyzed.

Results

Meibomian glands displayed robust transcriptome rhythmicity. HFD feeding significantly altered the circadian transcriptome profile of MGs—including composition and phase—and spatiotemporally affected the enriched signaling pathways. In addition, HFD feeding significantly altered the normal rhythmic oscillations of lipid components in MGs.

Conclusion

Our data show that HFD significantly affects MGs’ rhythmicity, which reveals a high sensitivity of MGs’ clocks to lipid composition in food.

Correlation Between Air Quality Index and Tear Film Lipid Layer Thickness: Comparison Between Patients with Sjogren's Syndrome and with Meibomian Gland Dysfunction

Purpose: To evaluate the effect of air pollution on the tear film stability by analyzing the correlation between Air Quality Index (AQI) and Lipid Layer thickness (LLT) in Xuzhou.Methods: As a prospective descriptive observational study, 284 patients with meibomian gland dysfunction (MGD), 157 patients with Sjögren's syndrome (SS), and 264 healthy volunteers were included. The tear film lipid layer thickness of the three groups of subjects was measured weekly and compared with the air quality index to analyze the correlation between the two indicators. Logistic regression analysis and linear regression analysis were used to analyze the effect of AQI on the thickness of the tear film lipid layer. The change of LLT with air pollution at different AQI levels was also analyzed.Results: There are obvious seasonal differences in the changes of air pollution index in Xuzhou. Significant differences could be observed in the thickness of the lipid layer of the tear film among the three groups. LLT in the MGD group and SS group decreased with the aggravation of air pollution, while remained unchanged in the control group. There was strong evidence of correlation between LLT of the MGD group (F = 353.494, p < 0.01, adjusted R2 = 0.695) and the SS group (F = 502.404, p < 0.01, adjusted R2 = 0.764) with AQI, while there was minor correlation between LLT with AQI in control group (F = 8.525, p < 0.01, adjusted R2 = 0.046).Conclusions: Air pollution can cause a decrease in the thickness of the tear film lipid layer, thereby affecting tear film stability, leading to the occurrence of dry eye.

A Review of Applications and Intracellular Mechanisms of Intense Pulsed Light in Eyelid Inflammatory Diseases

Objective: To evaluate relevant clinical outcomes and conclude possible mechanisms of intense pulsed light (IPL) in eyelid inflammation. Background: IPL devices were primarily applied in cutaneous vascular malformations and have been used in ocular diseases for about 20 years, mostly including meibomian gland dysfunction (MGD), blepharitis, and ocular rosacea. Recent findings: Seventy-two original clinical researches were included, 57 for MGD, 4 for blepharitis or blepharitis-related keratoconjunctivitis, and 11 for rosacea. Dry eye symptoms, (tear) break-up time (BUT), and meibomian structure and/or functions were improved in most patients, but production of reactive oxygen species is an important link in the photobiomodulation mediated by IPL, which can influence numerous signal pathways to achieve anti-inflammatory, anti-infective, and prodifferentiation effects. Conclusions: The evidence suggests that IPL is an effective therapeutic tool for most patients with MGD, but more clinical evidence is needed for other indications.

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.

Eye drops of human origin-Current status and future needs: Report on the workshop organized by the ISBT Working Party for Cellular Therapies

BACKGROUND AND OBJECTIVES

Serum eye drops (SEDs) are used to treat ocular surface disease (OSD) and to promote ocular surface renewal. However, their use and production are not standardized, and several new forms of human eye drops have been developed.

MATERIALS AND METHODS

The International Society for Blood Transfusion Working Party (ISBT WP) for Cellular Therapies held a workshop to review the current types of eye drops of human origin (EDHO) status and provide guidance.

RESULTS

The ISBT WP for Cellular Therapies introduced the new terminology 'EDHO' to emphasize that these products are analogous to 'medical products of human origin'. This concept encompasses their source (serum, platelet lysate, and cord blood) and the increasingly diverse spectrum of clinical usage in ophthalmology and the need for traceability. The workshop identified the wide variability in EDHO manufacturing, lack of harmonized quality and production standards, distribution issues, reimbursement schemes and regulations. EDHO use and efficacy is established for the treatment of OSD, especially for those refractory to conventional treatments.

CONCLUSION

Production and distribution of single-donor donations are cumbersome and complex. The workshop participants agreed that allogeneic EDHO have advantages over autologous EDHO although more data on clinical efficacy and safety are needed. Allogeneic EDHOs enable more efficient production and, when pooled, can provide enhanced standardization for clinical consistency, provided optimal margin of virus safety is ensured. Newer products, including platelet-lysate- and cord-blood-derived EDHO, show promise and benefits over SED, but their safety and efficacy are yet to be fully established. This workshop highlighted the need for harmonization of EDHO standards and guidelines.

Low-Level Light Therapy Versus Intense Pulsed Light for the Treatment of Meibomian Gland Dysfunction: Preliminary Results From a Prospective Randomized Comparative Study

PURPOSE

The purpose of this study was to evaluate and compare the safety and efficacy of low-level light therapy (LLLT) and intense pulsed light (IPL) for the treatment of meibomian gland dysfunction (MGD).

METHODS

Forty eyes of 40 patients with MGD were randomized to receive either LLLT or IPL. Four weekly sessions of LLLT (MY MASK-E, Espansione Marketing S.p.A., Bologna, Italy) and IPL (Eye-light device, Espansione Marketing S.p.A., Bologna, Italy) were performed. The following parameters were evaluated before and 2 weeks after the last session for each treatment: Standard Patient Evaluation of Eye Dryness questionnaire, noninvasive break-up time, tear meniscus height, redness score, meiboscore, and meibomian gland loss.

RESULTS

All patients completed regularly all the scheduled sessions, and no adverse events were reported in any of the groups. The Standard Patient Evaluation of Eye Dryness score significantly decreased after both LLLT and IPL (P < 0.001) although the improvement was significantly greater in the LLLT compared with the IPL group (-9.9 ± 3.2 vs. -6.75 ± 4.5; P = 0.014). Patients in the LLLT group showed a significantly higher increase in tear meniscus height compared with those in the IPL group (0.06 ± 0.10 mm vs. -0.01 ± 0.014; P = 0.040). In both groups, the noninvasive break-up time, redness score, meiboscore, and meibomian gland loss did not vary significantly after treatment (all P > 0.05).

CONCLUSIONS

Both LLLT and IPL were safe and effective in improving ocular discomfort symptoms in patients with MGD; however, the former determined a greater improvement in symptoms and an improvement of tear volume.

Effects of Serial Sessions of Activa Mask for the Treatment of Meibomian Gland Dysfunction

INTRODUCTION

To analyze outcomes on objective ocular surface parameters and subjective symptoms of serial weekly sessions using the Activa mask in patients with meibomian gland dysfunction (MGD).

METHODS

This is a prospective study including patients with symptomatic MGD who were treated with four weekly sessions using the Activa mask (SBM Sistemi, Turin, Italy). Noninvasive ocular surface examination was carried out before (T0) and 2 weeks after the last mask session (T1) using Idra (SBM Sistemi, Turin, Italy) for the measurement of: (1) noninvasive break-up time (NIBUT); (2) lipid layer thickness (LLT); (3) tear meniscus height (TMH); (4) meibomian gland loss (MGL) of upper and lower eyelids. The I-Pen tear osmolarity system (I-Med Pharma Inc, Dollard-des Ormeaux, Quebec, Canada) was used to measure tear osmolarity values. Ocular discomfort symptoms were ascertained by means of the ocular surface disease index (OSDI) questionnaire.

RESULTS

All 25 patients (11 males, 14 females; mean age 57.1 ± 11.9 years) regularly completed the cycle of four mask sessions. No patients used prohibited medications, and no device-related adverse events were noted. At T1, mean values of NIBUT and LLT increased significantly compared to T0 (respectively from 6.0 ± 1.4 to 6.6 ± 1.2 s, P = 0.043, and from 53.2 ± 17.4 to 65.3 ± 16.3 nm, P < 0.001), while mean values of MGL and tear osmolarity decreased significantly (respectively from 17.1 ± 9.3 to 15.1 ± 8.0%, P = 0.014, and from 307.3 ± 12.2 to 301.5 ± 6.8 mOsm/l, P = 0.005). In parallel, OSDI score reduced significantly from 62.4 ± 11.7 at T0 to 34.5 ± 11.2 at T1 (P < 0.001).

CONCLUSION

Weekly serial sessions using the Activa mask significantly improved objective parameters of the ocular surface as well as subjective ocular discomfort symptoms in patients with recalcitrant MGD. As a further benefit from the treatment, patients were able to avoid the use of concomitant medications, apart from tear substitutes, throughout the study.

Artificial intelligence-assisted diagnosis of ocular surface diseases

With the rapid development of computer technology, the application of artificial intelligence (AI) in ophthalmology research has gained prominence in modern medicine. Artificial intelligence-related research in ophthalmology previously focused on the screening and diagnosis of fundus diseases, particularly diabetic retinopathy, age-related macular degeneration, and glaucoma. Since fundus images are relatively fixed, their standards are easy to unify. Artificial intelligence research related to ocular surface diseases has also increased. The main issue with research on ocular surface diseases is that the images involved are complex, with many modalities. Therefore, this review aims to summarize current artificial intelligence research and technologies used to diagnose ocular surface diseases such as pterygium, keratoconus, infectious keratitis, and dry eye to identify mature artificial intelligence models that are suitable for research of ocular surface diseases and potential algorithms that may be used in the future.

Factors affecting the prevalence, severity, and characteristics of ocular surface pain

Introduction

Ocular surface pain has been traditionally lumped under the umbrella term "dry eye" (DE) but is now understood as its own entity and can occur in the absence or presence of tear dysfunction. Identifying patients at risk for the development of chronic ocular surface pain, and factors contributing to its severity are important in providing precision medicine to patients.

Areas covered

In this review, we discuss factors linked to the presence and severity of ocular surface pain, including eye related features, systemic characteristics, and environmental findings. We discuss corneal nerves, whose anatomic and functional integrity can be characterized through in vivo confocal microscopy images and testing of corneal sensitivity. We review systemic diseases that are co-morbid with ocular surface pain, including physical and mental health diagnoses. Finally, we identify environmental contributors, including air pollution, previous surgeries, and medications, associated with ocular surface pain.

Expert opinion

Intrinsic and extrinsic factors contribute to ocular surface pain and must be considered when evaluating an individual patient. These factors can inform the suspected etiology of the pain, and guide management decisions such as tear replacement or medications targeting nerve pain.

The Role of Ectodysplasin A on the Ocular Surface Homeostasis

Ectodysplasin A (EDA), a ligand of the TNF family, plays an important role in maintaining the homeostasis of the ocular surface. EDA is necessary for the development of the meibomian gland, the lacrimal gland, as well as the proliferation and barrier function of the corneal epithelium. The mutation of EDA can induce the destruction of the ocular surface resulting in keratopathy, abnormality of the meibomian gland and maturation of the lacrimal gland. Experimental animal studies showed that a prenatal ultrasound-guided intra-amniotic injection or postnatal intravenous administration of soluble recombinant EDA protein can efficiently prevent the development of ocular surface abnormalities in EDA mutant animals. Furthermore, local application of EDA could restore the damaged ocular surface to some extent. Hence, a recombinant EDA-based therapy may serve as a novel paradigm to treat ocular surface disorders, such as meibomian gland dysfunction and corneal epithelium abnormalities.

Therapeutic Potential of d-MAPPS™ for Ocular Inflammatory Diseases and Regeneration of Injured Corneal and Retinal Tissue

The invasion of microbial pathogens and/or sterile inflammation caused by physical/chemical injuries, increased ocular pressure, oxidative stress, and ischemia could lead to the generation of detrimental immune responses in the eyes, which result in excessive tissue injury and vision loss. The bioavailability of eye drops that are enriched with immunoregulatory and trophic factors which may concurrently suppress intraocular inflammation and promote tissue repair and regeneration is generally low. We recently developed “derived- Multiple Allogeneic Proteins Paracrine Signaling regenerative biologics platform technology d-MAPPS™”, a bioengineered biological product which is enriched with immunomodulatory and trophic factors that can efficiently suppress detrimental immune responses in the eye and promote the repair and regeneration of injured corneal and retinal tissues. The results obtained in preclinical and clinical studies showed that d-MAPPS™ increased the viability of injured corneal cells, inhibited the production of inflammatory cytokines in immune cells, alleviated inflammation, and restored vision loss in patients suffering from meibomian gland dysfunction and dry eye disease. Herewith, we emphasized molecular mechanisms responsible for the therapeutic efficacy of d-MAPPS™ and we presented the main beneficial effects of d-MAPPS™ in clinical settings, indicating that the topical administration of d-MAPPS™ could be considered a new therapeutic approach for the treatment of ocular inflammatory diseases and for the repair and regeneration of injured corneal and retinal tissues.

Systane iLux Thermal Pulsation System in the Treatment of Meibomian Gland Dysfunction: A Post-Hoc Analysis of a 12-Month, Randomized, Multicenter Study

Purpose

This study aimed to demonstrate the effectiveness of Systane iLux, a thermal pulsation device, in patients with MGD, over 12 months post-single treatment.

Methods

This is a post-hoc analysis of a previous prospective, assessor-masked, parallel-group, multicenter study (NCT03956225) that compared the effectiveness and safety of iLux with LipiFlow in subjects with MGD. The original study included subjects with meibomian gland score (MGS) ≤12 in lower eyelids, Impact of Dry Eye on Everyday Life-Symptom Bother (IDEEL-SB) module score &gt;16, and non-invasive tear break-up time (NITBUT) &lt;10 seconds. Subjects were randomized (1:1) to receive a single bilateral treatment of iLux or LipiFlow. In this post-hoc analysis, mean changes in MGS, NITBUT (first break-up; seconds), IDEEL-SB module score, and corneal staining, from baseline to 12 months were analyzed post-single treatment with iLux.

Results

Data from 119 patients (n=238 eyes) treated with iLux were analyzed. The mean±SD age of the subjects was 58.4±13.4 years, with majority being female (79.0%). MGS (mean±SD) for both eyes improved significantly from baseline to 12 months (OD [baseline: 6.9±3.69; month 12: 22.8±11.31; change: 15.9±11.57, p&lt;0.0001]; OS [baseline: 6.4±3.66; month 12: 23.0±11.33; change: 16.7±11.40, p&lt;0.0001]). Similarly, significant improvements were observed in NITBUT (OD [baseline: 5.2±1.97; month 12: 7.0±3.68; change: 1.9±3.69, p&lt;0.0001]; OS [baseline: 5.6±1.96; month 12: 7.9±4.58; change: 2.3±4.59, p&lt;0.0001]) and IDEEL-SB score (p&lt;0.0001). Corneal staining reduced significantly from baseline to 12 months (OD [baseline: 2.1±2.96; month 12: 0.7±1.56; change: -1.4±2.65, p&lt;0.0001]; OS [baseline: 2.1±2.94; month 12: 0.7±1.44; change: -1.4±2.75, p&lt;0.0001]). Improvements in MGS, NITBUT, IDEEL-SB module score, and corneal staining were seen as early as week 2, and at months 1, 3, 6, and 9 (all p&lt;0.001).

Conclusion

A single treatment with iLux significantly improved clinical parameters of MGS, NITBUT, and corneal staining, and patient-reported symptom assessment with IDEEL-SB in patients with MGD over 12 months.

Case report: Immune-mediated meibomian gland dysfunction following pembrolizumab therapy for advanced urothelial carcinoma

Ocular immune-related adverse events are a relatively rare complication of immune checkpoint inhibitors. Common ocular toxicities range from dry eyes to inflammatory uveitis and ocular myasthenia gravis. Here, we present the case of a 55-year-old woman with recurrent urothelial carcinoma of the ureter after initially being managed with neoadjuvant cisplatin-based chemotherapy and surgical resection. She was treated with pembrolizumab which was complicated by immune-mediated pneumonitis after the eighth cycle, which was managed with a prolonged steroid course. The patient also developed red eyes along with recurrent styes. Eye examination revealed decreased tear breakup time, expression of thick and turbid meibum, and meibomian gland atrophy on infrared meibography. The patient was diagnosed with suspected immune-mediated meibomian gland dysfunction (MGD) as a result of pembrolizumab, a previously unreported complication of immunotherapy. The goal of MGD therapy is to stabilize the tear film and minimize evaporation with lipid-based lubricants and other conservative treatments.

Spontaneous acinar and ductal regrowth after meibomian gland atrophy induced by deletion of FGFR2 in a mouse model

PURPOSE

We have demonstrated that deletion of fibroblast growth factor receptor 2 gene (Fgfr2) leads to Meibomian gland (MG) atrophy in an inducible conditional knockout mouse model, referred as Fgfr2^CKO. Herein, we investigated whether MG spontaneously recovers after atrophy in this model.

METHODS

Two months old Fgfr2^CKO mice were injected peritoneally once or twice of doxycycline (Dox) at 80 μg/gm of body weight to induce MG atrophy of various severities via Fgfr2 deletion. Recovery of acinar and ductal tissues was monitored by meibography, lipid staining and immunofluorescence against keratin-6a in MG whole-mount. Biomarkers for acinar and ductal differentiation and proliferation were also examined by immunostaining.

RESULTS

Single Dox injection in Fgfr2^CKO mice caused severe acinar and moderate ductal atrophy. Severe ductal shortening or loss occurred after second Dox injection, presumably related to the reported slower cycling of the ductal epithelia. Spontaneous acinar regrowth after atrophy was observed over a period of 60 days in both injection regimens. However, less robust acinar recovery was associated with more disrupted ductal structures in twice injected Fgfr2^CKO mice.

CONCLUSIONS

Our current findings further substantiate the role of FGFR2 in MG homeostasis, and suggest that FGFR2-signaling may provide a potential strategy for regenerating acini from age-related MG dysfunction in humans. Our data demonstrated that spontaneous MG recovery depends on the extent of ductal atrophy, suggesting that ductal epithelia may provide the progenitor cells for acinar regeneration. Nonetheless, the role of ductal tissue as the source of acinar progenitors awaits further investigation.