Meibomian glands and ocular surface inflammation

Advances in artificial intelligence for meibomian gland evaluation: A comprehensive review

Meibomian gland dysfunction (MGD) is increasingly recognized as a critical contributor to evaporative dry eye, significantly impacting visual quality. With a global prevalence estimated at 35.8 %, it presents substantial challenges for clinicians. Conventional manual evaluation techniques for MGD face limitations characterized by inefficiencies, high subjectivity, limited big data processing capabilities, and a dearth of quantitative analytical tools. With rapidly advancing artificial intelligence (AI) techniques revolutionizing ophthalmology, studies are now leveraging sophisticated AI methodologies--including computer vision, unsupervised learning, and supervised learning--to facilitate comprehensive analyses of meibomian gland (MG) evaluations. These evaluations employ various techniques, including slit lamp examination, infrared imaging, confocal microscopy, and optical coherence tomography. This paradigm shift promises enhanced accuracy and consistency in disease evaluation and severity classification. While AI has achieved preliminary strides in meibomian gland evaluation, ongoing advancements in system development and clinical validation are imperative. We review the evolution of MG evaluation, juxtapose AI-driven methods with traditional approaches, elucidate the specific roles of diverse AI technologies, and explore their practical applications using various evaluation techniques. Moreover, we delve into critical considerations for the clinical deployment of AI technologies and envisages future prospects, providing novel insights into MG evaluation and fostering technological and clinical progress in this arena.

Dual Role of Cutibacterium acnes: Commensal Bacterium and Pathogen in Ocular Diseases

Microbiota present around the ocular surface, encompassing the eyelid skin, the conjunctival sac, and the meibomian glands, play a significant role in various inflammatory conditions associated with the ocular surface. Cutibacterium acnes (C. acnes), formerly, Propionibacterium acnes, is one of the most predominant commensal bacteria and its relative abundance declines with aging. However, it can act as both an infectious and an immunogenic pathogen. As an infectious pathogen, C. acnes has been reported to cause late onset endophthalmitis post-cataract surgery and infectious keratitis. On the other hand, it can trigger immune responses resulting in conditions such as phlyctenules in the cornea, chalazion in the meibomian glands, and granuloma formation in ocular sarcoidosis. This review explores the role of C. acnes in ocular inflammation, specifically highlighting its implications for diagnosis and 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.

Clinical features and management of keratoconjunctivitis associated with inadequate tear drainage

OBJECTIVE

To describe clinical features and management of toxic keratoconjunctivitis associated with punctal and (or) canaliculus stenosis (toxic soup syndrome).

DESIGN

Retrospective observational case series.

METHODS

Electronic medical record database search for the keywords "toxic soup syndrome" and retrospective chart review were performed. Thirty-five eyes of 25 patients were seen at a tertiary cornea clinic between January 2017 and December 2021. Sex, age, distance-corrected visual acuity, topical medications, symptoms, clinical signs, and outcomes after medical and surgical interventions were analyzed. The main outcome measured was improvement in ocular surface signs and symptoms after interventions.

RESULTS

Overall, 35 eyes of 25 patients with a mean age of 66.8 ± 12.8 years, of which 72% were female, were included. The primary complaint was hyperemia and epiphora in all patients. Rosacea or meibomian gland disease were present in all patients, 7 (28%) had glaucoma, and 7 (28%) developed limbal stem cell deficiency. Twenty-two patients (88%) were using topical medications on presentation. All eyes had either punctal plugs, cauterized puncta, or punctal and (or) canaliculus stenosis. Management of all patients consisted of suspension of all preserved topical medications and institution of some type of anti-inflammatory therapy. Nineteen patients (76%) improved after improvement of lacrimal drainage. One patient with severe resistance in the canaliculus required ongoing preservative-free topical steroids.

CONCLUSIONS

Chronic drug-induced or pooled inflammatory mediators causing toxic conjunctivitis may be aggravated by punctal and (or) canaliculus stenosis, leading to toxic soup syndrome. Clearance of punctal obstruction leads to improvement in most patients.

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.

Immunophenotypic profiles in chalazion and pyogenic granuloma associated with chalazion

PURPOSE

To evaluate immunophenotypic profiles of infiltrating cells in surgically excised tissues of chalazion and pyogenic granuloma associated with chalazion.

METHODS

Eighty-two surgical specimens from 74 consecutive patients newly diagnosed with chalazion or chalazion-associated pyogenic granuloma at Tokyo Medical University Hospital between 2016 and 2022 were studied. Sixty specimens were chalazion lesions and 22 specimens were pyogenic granuloma lesions (from 15 men and 7 women, mean age 36.6 ± 14.4 years). All patients were immunocompetent Asian Japanese adults. Specimens were analyzed by immunohistochemistry and flow cytometry. Flow cytometry was performed using the following antibodies: CD3, CD4, CD8, CD11b, CD11c, CD16, CD19, CD20, CD23, CD25, CD34, CD44, CD56, CD69, and CD138.

RESULTS

In flow cytometric analysis, the proportion of cells expressing the T cell marker CD3 was significantly higher compared with other immune cells expressing specific markers (p < 0.0001), and the proportion of CD4-positive T cells was significantly higher than that of CD8-positive T cells (p < 0.0001), in both chalazion and pyogenic granuloma specimens. The chalazion and pyogenic granuloma lesions shared similar immunophenotypic profile characterized by predominant T cell infiltration, and CD4 T cells dominating over CD8 cells. The pattern of expression of CD4 and CD8 in the specimens was confirmed by immunohistochemistry.

CONCLUSION

The present study demonstrates immunophenotypic features of chalazion and chalazion-associated pyogenic granuloma. Although various inflammatory cells are involved in the pathology of chalazion and pyogenic granuloma, a significantly higher proportion of CD4-positive T cells may be closely related to the pathological mechanisms of both lesions.

The Use of Venous Catheter and Irrigation with Povidone-Iodine 0.6% in Patients with Punctal and Proximal Canalicular Stenosis: Preliminary Report

Background: This study aimed to evaluate the safety and efficacy of povidone-iodine 0.6% (PVI) irrigation for preventing recurrence of stenosis after punctoplasty in patients with punctal and proximal canalicular stenosis treated using a venous catheter as a stent. Methods: Twenty patients were enrolled and divided into two groups. Group 1 received irrigation of 1 mL 0.6% PVI, while Group 2 received 1 mL of balanced salt solution (BSS). The patients underwent baseline, 15-, 30-, and 90-day assessments using the Ocular Surface Disease Index (OSDI) questionnaire, Symptoms Assessment in Dry Eye (SANDE), Schirmer I test, tear meniscus height (TMH), bulbar redness, meibography, and non-invasive breakup time (NIKBUT) through Keratograph 5M (Oculus, Germany). Results: At three months, both groups demonstrated statistically significant improvements in symptoms and ocular surface parameters. However, Group 1 showed statistically significant improvements in OSDI, SANDE scores, bulbar redness, and NIKBUT compared to Group 2. Additionally, no patients in Group 1 presented a recurrence of stenosis, while three patients in Group 2 demonstrated stenosis relapse at the end of the follow-up period. Conclusions: The application of a venous catheter and PVI 0.6% irrigations proved to be effective in treating proximal lacrimal duct stenosis, reducing the risk of recurrence and improving tear film stability, ocular discomfort symptoms, and ocular surface parameters.

The Features and Treatment Effects on Keratoepitheliopathy for Meibomitis-Related Keratoconjunctivitis

Meibomitis-related keratoconjunctivitis (MRKC) is characterized by meibomitis with corneal epithelial abnormalities, and can be divided into two types: MRKC accompanied with phlyctenular keratitis, and MRKC accompanied with keratoepitheliopathy that is similar to superficial punctate keratopathy (SPK). The purpose of this retrospective study was to investigate the characteristic features of keratoepitheliopathy and treatment outcomes for MRKC. This study involved 27 eyes of 18 MRKC patients (3 males and 15 females). National Eye Institute (NEI) scores and visual acuity were compared at pre and post treatment. All subjects were treated with a small-dose administration of clarithromycin. Keratoepitheliopathy characteristic to MRKC, yet different in appearance from SPK, was noted in 24 of the 27 eyes. Fluorescein staining revealed granular epithelial lesions generally larger than SPK that coexisted with small dark spots. In 17 eyes, keratoepitheliopathy was located within the pupillary zone, and the visual acuity in 12 eyes was less than 1.0. Our findings showed significant improvement in the NEI score in MRKC (p < 0.0001) and in visual acuity (p = 0.0157) post treatment, and the characteristic features of keratoepitheliopathy in MRKC that are often associated with decreased visual acuity were elucidated. The treatment of clarithromycin was found to be effective for MRKC with keratoepitheliopathy.

Definition and Diagnostic Criteria for Pediatric Blepharokeratoconjunctivitis

Importance

Pediatric blepharokeratoconjunctivitis (PBKC) is a chronic, sight-threatening inflammatory ocular surface disease. Due to the lack of unified terminology and diagnostic criteria, nonspecific symptoms and signs, and the challenge of differentiation from similar ocular surface disorders, PBKC may be frequently unrecognized or diagnosed late.

Objective

To establish a consensus on the nomenclature, definition, and diagnostic criteria of PBKC.

Design, Setting, and Participants

This quality improvement study used expert panel and agreement applying the non-RAND modified Delphi method and open discussions to identify unified nomenclature, definition, and definitive diagnostic criteria for PBKC. The study was conducted between September 1, 2021, and August 14, 2022. Consensus activities were carried out through electronic surveys via email and online virtual meetings.

Results

Of 16 expert international panelists (pediatric ophthalmologists or cornea and external diseases specialists) chosen by specific inclusion criteria, including their contribution to scientific leadership and research in PBKC, 14 (87.5%) participated in the consensus. The name proposed was "pediatric blepharokeratoconjunctivitis," and the agreed-on definition was "Pediatric blepharokeratoconjunctivitis is a frequently underdiagnosed, sight-threatening, chronic, and recurrent inflammatory eyelid margin disease associated with ocular surface involvement affecting children and adolescents. Its clinical spectrum includes chronic blepharitis, meibomitis, conjunctivitis, and corneal involvement ranging from superficial punctate keratitis to corneal infiltrates with vascularization and scarring." The diagnostic criteria included 1 or more suggestive symptoms accompanied by clinical signs from 3 anatomical regions: the eyelid margin, conjunctiva, and cornea. For PBKC suspect, the same criteria were included except for corneal involvement.

Conclusions and Relevance

The agreements on the name, definition, and proposed diagnostic criteria of PBKC may help ophthalmologists avoid diagnostic confusion and recognize the disease early to establish adequate therapy and avoid sight-threatening complications. The diagnostic criteria rely on published evidence, analysis of simulated clinical cases, and the expert panel's clinical experience, requiring further validation with real patient data analysis.

Isolation and Culture of Human Meibomian Gland Ductal Cells

Purpose

Hyperkeratinization of meibomian gland (MG) ducts is currently recognized as the primary pathologic mechanism of meibomian gland dysfunction (MGD). This research figured out a method to isolate the MG ducts and established a novel system to culture the human meibomian gland ductal cells (HMGDCs) for investigating the process of MGD.

Methods

The MG ducts were obtained from the eyelids of recently deceased donors and subjected to enzymatic digestion. The acini were then removed to isolate independent ducts. These MG ducts were subsequently cultivated on Matrigel-coated wells and covered with a glass plate to obtain HMGDCs. The HMGDCs were further cultivated until passage 2, and when they reached 60% confluence, they were treated with IL-1β and rosiglitazone for a duration of 48 hours. Immunofluorescence staining and Western blot techniques were employed to identify ductal cells and analyze the effects of IL-1β on HMGDCs in an in vitro setting.

Results

Ophthalmic micro-forceps and insulin needles can be employed for the purpose of isolating ducts. Within this particular culture system, the rapid expansion of HMGDCs occurred in close proximity to the duct tissue. MG ducts specifically expressed keratin 6 (Krt6) and hardly synthesized lipids. Furthermore, the expression of Krt6 was significantly higher (P < 0.0001) in HMGDCs compared to human meibomian gland cells. Upon treatment with IL-1β, HMGDCs exhibited an overexpression of keratin 1, which was effectively blocked by the administration of rosiglitazone.

Conclusions

The present study successfully isolated human MG ducts and cultured HMGDCs, providing a valuable in vitro model for investigating the mechanism of MGD. Additionally, the potential therapeutic efficacy of rosiglitazone in treating hyperkeratinization of ducts in patients with MGD was identified.

The effects of chalazion and the excision surgery on the ocular surface

Purpose

To evaluate the effects of chalazion excision on the ocular surface, taking into account the subjective symptoms and the objective parameters of the tear film.

Methods

This prospective, interventional clinical study included 52 eyes from 26 patients with eyelid chalazion who underwent excision of the lesions between March and August 2022. Chalazion excision was performed on the patient's chalazion eye, and the contralateral eye served as the control. The following parameters were investigated both preoperatively and 1 week, 1 month, and 3 months postoperatively: the Ocular Surface Disease Index (OSDI), Schirmer I test, corneal fluorescein stain (CFS), tear meniscus height (TMH), noninvasive first breakup time (NifBUT), noninvasive average breakup time (NiaBUT), bulbar conjunctival redness score, the thickness of the lipid layer, and meibomian gland loss.

Results

Before surgery, the OSDI score of the chalazion eye was significantly higher than the contralateral eye. The bulbar conjunctival redness score (p = 0.043) and the OSDI score (p = 0.004) improved significantly in the first month after surgery. In the third month after surgery, the objective parameters showed significant improvements, including TMH (p = 0.032), NiaBUT (p = 0.028), bulbar conjunctival redness score (p < 0.001), the thickness of the lipid layer (p = 0.021), and meibomian gland loss (p = 0.005).

Conclusions

Our study revealed that chalazion excision can significantly improve the subjective symptoms and the objective tear film parameters of the ocular surface.

Efficacy of azithromycin hydrate ophthalmic solution for treatment of internal hordeolum and meibomitis with or without phlyctenular keratitis

PURPOSE

To evaluate the efficacy of azithromycin hydrate ophthalmic solution for the treatment of internal hordeolum and meibomitis with or without phlyctenular keratitis.

STUDY DESIGN

Retrospective study.

METHODS

Patients diagnosed with internal hordeolum or meibomitis were prescribed azithromycin hydrate ophthalmic solution twice daily for 2 days and then once daily for 12 days. Depending on the presence of meibomitis-related keratoconjunctivitis (MRKC), we further divided the patients with meibomitis into three subgroups: meibomitis alone (non-MRKC group), meibomitis with non-phlyctenular MRKC (non-phlyctenular group), and meibomitis with phlyctenular MRKC (phlyctenular group). Inflammatory findings (eyelid redness and conjunctival hyperemia) were scored before and after treatment. Some patients also underwent culture testing fluids discharged by the meibomian gland orifices.

RESULTS

Three patients (3 eyes) had internal hordeolum and 16 patients (16 eyes) had meibomitis. After treatment, the inflammatory findings disappeared in all eyes with internal hordeolum. Among the patients with meibomitis, three eyes were in the non-MRKC, six in the non-phlyctenular, and seven in the phlyctenular group. The inflammatory findings were significantly improved only in the phlyctenular group. Among seven eyes with positive culture results, Cutibacterium acnes was detected in five, and treatment improved the inflammatory findings in all of these eyes.

CONCLUSION

Azithromycin hydrate ophthalmic solution is effective for the treatment of inflammatory meibomian gland diseases, including internal hordeolum and meibomitis. In particular, the agent is highly efficient in patients with phlyctenular MRKC.

Integrated multi-omics and machine learning approach reveals lipid metabolic biomarkers and signaling in age-related meibomian gland dysfunction

Meibomian gland dysfunction (MGD) is a prevalent inflammatory disorder of the ocular surface that significantly impacts patients' vision and quality of life. The underlying mechanism of aging and MGD remains largely uncharacterized. The aim of this work is to investigate lipid metabolic alterations in age-related MGD (ARMGD) through integrated proteomics, lipidomics and machine learning (ML) approach. For this purpose, we collected samples of female mouse meibomian glands (MGs) dissected from eyelids at age two months (n = 9) and two years (n = 9) for proteomic and lipidomic profilings using the liquid chromatography with tandem mass spectrometry (LC-MS/MS) method. To further identify ARMGD-related lipid biomarkers, ML model was established using the least absolute shrinkage and selection operator (LASSO) algorithm. For proteomic profiling, 375 differentially expressed proteins were detected. Functional analyses indicated the leading role of cholesterol biosynthesis in the aging process of MGs. Several proteins were proposed as potential biomarkers, including lanosterol synthase (Lss), 24-dehydrocholesterol reductase (Dhcr24), and farnesyl diphosphate farnesyl transferase 1 (Fdft1). Concomitantly, lipidomic analysis unveiled 47 lipid species that were differentially expressed and clustered into four classes. The most notable age-related alterations involved a decline in cholesteryl esters (ChE) levels and an increase in triradylglycerols (TG) levels, accompanied by significant differences in their lipid unsaturation patterns. Through ML construction, it was confirmed that ChE(26:0), ChE(26:1), and ChE(30:1) represent the most promising diagnostic molecules. The present study identified essential proteins, lipids, and signaling pathways in age-related MGD (ARMGD), providing a reference landscape to facilitate novel strategies for the disease transformation.

Transitory alkali exposure on meibomian gland orifices induces meibomian gland dysfunction

PURPOSE

To determine pathological changes of meibomian glands (MGs) after transient exposure of the rat eyelid margin to alkali solution.

METHODS

Filter paper infiltrated with 1 N sodium hydroxide solution was applied to the eyelid margin of Sprague-Dawley rats for 30 s under general anesthesia, without touching the conjunctiva, after which the ocular surface and eyelid margin were examined by slit-lamp microscopy. In vivo confocal microscopy and stereomicroscopy were subsequently applied to observe MG morphology on day 5, day 10 and day 30 post alkali injury. Eyelid cross-sections were processed for H&E staining, Oil red O staining and immunofluorescent staining.

RESULTS

After alkali injury, there was marked plugging of MG orifices, telangiectasia and hypertrophy of the eyelid margin, while corneal epithelium was intact at post-injury days 5 and 10. However, 30 days after alkali injury, mild corneal epithelial damage was observed. Degeneration of MG acini was observed at days 5 and became aggravated at days 10 and 30, along with MG duct dilation and acini loss. Oil red O staining showed lipid accumulation in the dilated duct. Inflammatory cell infiltration and the presence of apoptotic cells was seen in the MG loci 5 days post injury, but diminished at days 10 and 30. Cytokeratin 10 expression was increased in dilated duct, while cytokeratin 14, PPAR-γ, Ki67 and LRIG1 expression were decreased in the acini of injured loci.

CONCLUSIONS

Transitory alkali exposure of the rat eyelid margin obstructs the MG orifice and induces pathological changes of MG dysfunction.

Cutibacterium (Formerly Propionibacterium ) acnes Keratitis: A Review

ABSTRACT

Infectious keratitis is a devastating cause of vision loss worldwide. Cutibacterium acnes ( C. acnes ), a commensal bacterium of the skin and ocular surface, is an underrecognized but important cause of bacterial keratitis. This review presents the most comprehensive and up-to-date information for clinicians regarding the risk factors, incidence, diagnosis, management, and prognosis of C. acnes keratitis (CAK). Risk factors are similar to those of general bacterial keratitis and include contact lens use, past ocular surgery, and trauma. The incidence of CAK may be approximately 10%, ranging from 5% to 25% in growth-positive cultures. Accurate diagnosis requires anaerobic blood agar and a long incubation period (≥7 days). Typical clinical presentation includes small (<2 mm) ulcerations with deep stromal infiltrate causing an anterior chamber cell reaction. Small, peripheral lesions are usually resolved, and patients recover a high visual acuity. Severe infections causing VA of 20/200 or worse are common and often do not significantly improve even after treatment. Vancomycin is considered the most potent antibiotic against CAK, although other antibiotics such as moxifloxacin and ceftazidime are more commonly used as first-line treatment.

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.

Dry Eye Disease: What Is the Role of Vitamin D?

Dry eye disease (DED) is a multifactorial condition resulting from reduced tear secretion from the lacrimal glands, increased tear water evaporation or the production of poor-quality tears. Such tear instability can lead to inflammation and damage of the ocular surface, as well as to abnormal nociception. Historically, tear substitutes and corticosteroids have been the bastion of DED therapy, but a substantial number of patients still suffer from residual symptoms even after being treated with traditional treatments. Aiming to find safe and effective alternative therapies, recent efforts have been focused on the role of vitamin D in the cellular physiology of the eye. Possibly because of its positive effect in modulating the immune and inflammatory responses, the systemic supplementation of vitamin D seems, indeed, to be an effective therapeutic strategy, especially, but not only, for patients affected by DED that does not respond to conventional treatments. In this context, this review focuses on the literature reporting on the pathogenesis and treatment of DED, with a special emphasis on the recent investigations reporting on the potential role of the systemic administration of vitamin D as a therapeutic approach in the management of such condition.

Impact of meibomian gland dysfunction on quality of life and mental health in a clinical sample in Ghana: a cross-sectional study

OBJECTIVES

This study aimed to determine the impact of meibomian gland dysfunction (MGD) on quality of life and psychosomatic conditions.

DESIGN

This was a clinic-based cross-sectional study.

SETTING

This study was conducted at the eye clinic of the University of Cape Coast, Ghana.

PARTICIPANTS

215 clinical subjects visiting the clinic for a comprehensive eye examination.

PRIMARY AND SECONDARY OUTCOME MEASURES

Symptomatic MGD, asymptomatic MGD, quality of life scores, depression, anxiety and stress.

RESULTS

215 clinical subjects consented to participate in the study, but 212 were included in the analysis. The mean age was 21.9 (± 3.8) years, 54 had MGD and 158 did not have MGD served as controls. There was no statistically significant difference in the mean quality of life scores between subjects with MGD and subjects without MGD (t=1.57, p=0.12). The quality of life scores (DEQS) (p=0.022) were significantly higher in the symptomatic MGD group compared with the asymptomatic MGD group. There was no significant difference in quality of life scores (DEQS) (p=0.251) in the asymptomatic MGD group compared with healthy controls. Using Pillai's trace in the MANOVA, there was a significant effect of MGD on depression, anxiety and stress (V=0.05, F(3,208)=3.76, p=0.012). Furthermore, Pillai's trace in the MANOVA showed a significant difference between asymptomatic and symptomatic MGDs for depression, anxiety and stress scores stress (V=0.24, F(3, 51)=5.24, p=0.003).

CONCLUSION

The study revealed no difference in the quality of life scores between MGD and non-MGD groups. However, the symptomatic MGD group had worse quality of life and psychosomatic symptoms than the asymptomatic MGD group and non-MGD group.

Topographical Distribution and Phenotype of Resident Meibomian Gland Orifice Immune Cells (MOICs) in Mice and the Effects of Topical Benzalkonium Chloride (BAK)

Meibomian gland orifices (MGOs) are located along the eyelid margin and secrete meibum into the tear film. The profile of resident innate immune cells (ICs) at this site is not well understood. The distribution and phenotype of resident ICs around MGOs in mice was investigated and herein defined as MGO-associated immune cells (MOICs). The effect of topical 0.1% benzalkonium chloride (BAK) on MOICs was also assessed. Eyelids from healthy CD11ceYFP and Cx3cr1gfp/gfp mice aged three or seven months were compared. ICs were identified as CD11c+, Cx3cr1+, and MHC-II+ using four-colour immunostaining and confocal microscopy. MOIC density was variable but clustered around MGOs. There were more CD11c+ MOICs in three-month-old compared with seven-month-old mice (three-month-old: 893 ± 449 cells/mm2 vs. seven-month-old: 593 ± 493 cells/mm2, p = 0.004). Along the eyelid margin, there was a decreasing gradient of CD11c+ MOIC density in three-month-old mice (nasal: 1003 ± 369 cells/mm2, vs. central: 946 ± 574 cells/mm2, vs. temporal: 731 ± 353 cells/mm2, p = 0.044). Cx3cr1-deficient mice had two-fold fewer MHC-II+ MOICs, suggesting a role for Cx3cr1 receptor signaling in meibomian gland surveillance. CD11c+ MOIC density was lower in BAK-exposed eyes compared to saline-treated controls, suggesting a change in homeostasis. This study provides novel insight into resident ICs located at MGOs, and their contribution to MG homeostasis.

A Water-Free Omega-3 Fatty Acid Eye Drop Formulation for the Treatment of Evaporative Dry Eye Disease: A Prospective, Multicenter Noninterventional Study

Purpose: NovaTears^®+Omega-3 is a water-free eye drop solution with non-animal-derived omega-3 fatty acids. It allows to supplement omega-3 fatty acids directly in the tear film of patients with dry eye disease (DED). This post-market clinical follow-up (PMCF) study evaluated for the first time the effects on clinical signs and patient symptoms of DED, and safety and tolerability of NovaTears+Omega-3 (0.2%) eye drops, when used in accordance with its approved label. Methods: A prospective, multicenter, single-arm, uncontrolled, open-label observational cohort study was performed in patients suffering from symptoms of evaporative DED. Patients were treated 4 times daily bilaterally according to the instructions for use for 8 weeks, and standard of care clinical end points were assessed at baseline and follow-up. The trial was conducted at 2 investigational sites in Germany, Europe. Results: Thirty-six patients were included and 33 completed the study. NovaTears+Omega-3 (0.2%) showed clinically and statistically significant improvements in various clinical signs, such as total corneal staining, tear film break-up time, and Meibomian gland dysfunction (MGD) score, as well as in symptoms measured by Ocular Surface Disease Index (OSDI^©) and visual analog scales over the 8-week treatment period with change from baseline P values all <0.0001. No worsening of any safety parameter (intraocular pressure, slit-lamp examination, visual acuity) was observed, and no adverse event was reported throughout the study. Conclusions: In this observational PMCF study, NovaTears+Omega-3 was safe and well tolerated. Treatment over an 8-week period resulted in significantly improved clinical signs and subjective symptoms in patients with evaporative dry eye. The study was registered at www.clinicaltrials.gov (NCT04521465).

Demodex folliculorum Infestation in Meibomian Gland Dysfunction Related Dry Eye Patients

Objective

To report the influence of Demodex folliculorum (D. folliculorum) infestation in patients with meibomian gland dysfunction (MGD) related dry eye and the associations of the infestation with MGD related dry eye.

Methods

Eyelashes (three from the upper eyelid and three from the lower eyelid) from 119 eyes of 119 patients diagnosed with MGD related dry eye were examined under a light microscope. There were 68 eyes of 68 patients with MGD related dry eye and D. folliculorum infestation (Demodex positive group) and 51 eyes of 51 patients without infestation (Demodex negative group). All patients completed an Ocular Surface Disease Index (OSDI) questionnaire and underwent tests for dry eye and MGD. The tests included fluorescein tear breakup time (TBUT), corneal fluorescein staining, Schirmer I test (SIT), lid margin abnormalities, meibum expression assessment, and meibomian gland dropout.

Results

The scores for OSDI, corneal fluorescein staining, lid margin abnormalities, meibum expression, and meibomian gland dropout were significantly higher (all P &lt; 0.05), while TBUT was significantly shorter in the Demodex positive group compared to the Demodex negative group (P = 0.020). The SIT values did not significantly differ between groups. Chalazion was significantly more prevalent in the Demodex positive group. The number of D. folliculorum was positively correlated with all three MGD parameters (P ≤ 0.035), OSDI; corneal fluorescein scores, and it was inversely correlated with BUT. The correlation for SIT was R2 = 0.075 (P = 0.064).

Conclusion

Demodex folliculorum infestation is possibly one of the key contributors in the pathogenesis of MGD related dry eye, and a higher prevalence of chalazion was found in D. folliculorum infected patients. The possible causal role of D. folliculorum infestation needs to be further studied.

Preferred practice patterns for photorefractive keratectomy surgery

Over the past two decades, excimer laser-based refractive surgery procedures have been successfully established for their safety and satisfactory visual outcomes. Surface ablation procedures or photorefractive keratectomy (PRK) are practised commonly for the correction of refractive errors including myopia, astigmatism and hyperopia. Satisfactory visual outcomes are achieved in majority of cases, although a very small percentage have issues related to corneal haze, regression, and its associated visual disturbances. To ensure optimal outcomes and to minimize complications, certain keys to success have been designed on the basis of the current review of literature on surface ablation procedures.

Dry eye: why artificial tears are not always the answer

Dry eye disease (DED) is a multifactorial disease that manifests in patients with a variety of symptoms and signs such as ocular pain, visual issues, rapid tear evaporation and/or decreased tear production. It is a global health problem and is the leading cause of optometry and ophthalmology clinic visits. The mainstay therapy for DED is artificial tears (ATs), which mimics tears and improves tear stability and properties. ATs have been found to improve symptoms and signs of disease in all DED subtypes, including aqueous deficient DED and evaporative DED. However, given the heterogeneity of DED, it is not surprising that ATs are not effective in all patients. When AT fails to relieve symptoms and/or signs of DED, it is critical to identify the underlying contributors to disease and escalate therapy appropriately. This includes underlying systemic diseases, meibomian gland dysfunction, anatomical abnormalities and neuropathic dysfunction. Thus, this review will discuss the benefits and limitations of ATs and review conditions when escalation of therapy should be considered in DED.

Ocular surface characteristics in acne vulgaris

Clinical relevance: Since acne vulgaris is a disease of the sebaceous glands, it may have potential effects on the ocular surface and tear homoeostasis, which are essential for good vision. Optometrists should be aware of ocular surface pathologies when prescribing glasses or contact lenses for the visual rehabilitation of these young patients.Background: To evaluate the ocular surface features, meibomian glands, and tear parameters of patients with acne vulgaris.Methods: The right eyes of 70 individuals (34 patients with acne vulgaris, 36 healthy volunteers) were evaluated. The tear break-up time of participants was measured, and the Schirmer test was performed. Then, to determine ocular surface characteristics, samples were taken from the conjunctiva for impression cytology. Finally, the loss rates of the upper and lower eyelid meibomian glands were determined by taking meibography (Sirius, CSO, Florence, Italy).Results: Tear break-up time was significantly lower in the study group compared to the control group (p < 0.001). No statistically significant difference was determined between the groups in respect of Nelson grade in the conjunctival impression cytology (p = 0.141). Grade 3 cytological changes were not observed in either group. The median value of the loss rate in the meibomian glands in the upper eyelid of patients with acne vulgaris was 19.10% (IQR: 18%), while it was 8.75% (IQR: 9.53%) in the control group (p = 0.001). The median value of the loss rate in the meibomian glands in the lower eyelid was 15.70% (IQR: 15.13%) and 7.70% (IQR: 6.53%) in the acne vulgaris and control groups, respectively (p < 0.001).Conclusion: Our study shows that patients with acne vulgaris may have a predisposition to meibomian gland damage and tear instability. Therefore, we consider that a more detailed ophthalmologic examination should be performed in patients with acne vulgaris.

Injectable bio-responsive hydrogel for therapy of inflammation related eyelid diseases

Eyelid plays a vital role in protecting the eye from injury or infection. Inflammation related eyelid diseases, such as blepharitis, are the most common ocular disorders that affect human's vision and quality of life. Due to the physiological barriers and anatomical structures of the eye, the bioavailability of topical administrated therapeutics is typically less than 5%. Herein, we developed a bio-responsive hydrogel drug delivery system using a generally recognized as safe compound, triglycerol monostearate (TG-18), for in-situ eyelid injection with sustained therapeutics release. In vitro, drug release and disassembly time of Rosiglitazone loaded hydrogel (Rosi-hydrogel) were estimated in the presence or absence of MMP-9, respectively. Moreover, the disassembly of TG-18 hydrogel was evaluated with 9-month-old and 12-month-old mice in vivo. Owing to the bio-responsive nature of Rosi-hydrogel, the on-demand Rosiglitazone release is achieved in response to local enzymes. These findings are proved by further evaluation in the age-related meibomian gland dysfunction mice model, and the bio-responsive hydrogel is used as an in-situ injection to treat eyelid diseases. Taken together, the in-situ eyelid injection with sustained drug release opens a window for the therapy of inflammation related eyelid diseases.

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This study is the first application of injectable bio-responsive hydrogel for therapy of inflammation related eyelid diseases.

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The enzyme response characteristic is extremely suitable for enhancing drug bioavailability in ocular drug delivery.

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In-situ release of rosiglitazone can effectively treat age-related meibomian gland dysfunction in the mice model.

Photorefractive keratectomy (PRK) Prediction, Examination, tReatment, Follow-up, Evaluation, Chronic Treatment (PERFECT) protocol - A new algorithmic approach for managing post PRK haze

Purpose

The aim of this study was to discuss the possible risk factors predisposing to post photorefractive keratectomy (PRK) haze formation and develop and validate a risk scoring system, so that this could be applied to our clinical practice as an algorithmic approach.

Methods

Study was divided into 2 arms, in the retrospective arm we looked at 238 eyes of patients undergoing PRK where certain presumed risk factors from literature and clinical experience were identified and statistical significance of association was studied in the development of corneal haze. The risk scoring system was applied to the 450 eyes in the prospective arm for validation. This was then used to formulate an algorithmic approach to manage post-PRK haze.

Results

22 out of 238 eyes in the retrospective arm developed haze where risk factors such as contact lens intolerance, altered tear film break up time, meibomian gland drop out and vitamin d levels were significantly associated with post-PRK haze (p < 0.05) and these factors were identified in the prospective arm. Treatment of these modifiable factors led to a significant reduction in post-PRK haze.

Conclusion

Thus identifying and treating risk factors of haze in patients undergoing PRK could improve surgical outcomes and patient satisfaction.

Meibomian gland dysfunction model induced with complete Freund's adjuvant in C57BL/6 mice

AIM

To establish a new inflammatory animal model of meibomian gland dysfunction (MGD) in C57BL/6 mice.

METHODS

C57BL/6 mice were randomly divided into complete Freund's adjuvant (CFA) group (14 animals, 14 eyes), naphthazolin hydrochloride (NH) group (14 animals, 14 eyes) and control group (14 animals, 14 eyes). In CFA group, CFA was used in eyelid conjunctiva injection; in NH group, NH eye drops were used twice a day; control group was injected with equal dose of saline at the same time point and same site with animals in CFA group. The meibomian gland orifices score (MGOS) was evaluated on a scale of 0 to 3 in the middle five meibomian gland orifices of the upper and lower eyelid using slit lamp. After the successful induction of each animal model, intense pulsed light (IPL) was introduced on each mouse in CFA and NH group. Oil red O (ORO), hematoxylin and eosin (H&E) staining were performed before and after successful induction of CFA, NH and control group.

RESULTS

At 12wk after CFA injection, inflammatory cell infiltration and fiber necrosis was observed, with acinar density and duct dilatation significantly lower compared with control group. In NH group, the meibomian gland acini were relatively smaller and deformed compared with control group, the number of meibomian gland acini was also slightly lower. No inflammatory cell or fiber necrosis was observed in NH group. After three times of IPL treatment (5/10 mice in each group, and the other 5 mice served as non-IPL control), MGOS was significantly lower in IPL-treated mice in NH group (P<0.01). After three times of IPL treatment, the MGOS of NH group was significantly lower than that in the CFA group (P<0.01).

CONCLUSION

We develop a novel animal model that studies the role of inflammation in the development of MGD and IPL treatment. This model indicates that persistent inflammatory state may be the cause of MGD and weaken the therapeutic effect of IPL.

Delineating a novel metabolic high triglycerides-low waxes syndrome that affects lipid homeostasis in meibomian and sebaceous glands

Meibomian glands that are embedded in tarsal plates of human eyelids, and sebaceous glands found in the skin, including that of eyelids, are two related types of holocrine glands that produce lipid-rich secretions called meibum and sebum. Pervasive ocular disorders, such as Meibomian gland dysfunction and dry eye, have been linked to changes in the lipid composition of meibum. However, in most described cases the changes were either small, or random, or insufficiently characterized on the molecular level. Here, we present results of comprehensive lipidomic analyses of meibum, tears and sebum of a patient whose secretions were highly abnormal (abnormal meibum, tears and sebum, or AMTS, patient). The lipidomes were characterized on the level of individual lipid species using ultra-high performance liquid chromatography and high resolution mass spectrometry. The major differences between the AMTS patient and normal age- and gender-matched subjects included, among others, severely diminished pools of normal meibomian lipids such as wax esters and cholesteryl esters in meibum and tears, a 2x increase in total cholesteryl esters to wax esters ratio, their skewed molecular profiles, a ~3x increase in free cholesterol to cholesteryl esters ratio, and, most importantly, a 20x to 30x increase in the triglicerides fraction over the norm. Sebum of the AMTS patient was also highly abnormal lacking major wax esters. Notably, the routine blood lipid panel test of the AMTS patient showed no abnormalities. The data imply that the AMTS patient had a severe, previously unreported, metabolic disorder that affected meibogenesis in Meibomian glands and sebogenesis in sebaceous glands. This is, to the best of our knowledge, a first observation of the condition that we have termed High Triglycerides/Low Waxes (HTLW) syndrome.

Corneal higher-order aberrations in phlyctenular keratitis

PURPOSE

To characterize tomographic patterns and quantify corneal higher-order aberrations (HOAs) in eyes with corneal scar due to phlyctenular keratitis.

STUDY DESIGN

Retrospective consecutive case series.

METHODS

This study included 51 eyes of 38 patients (24 women; 14 men) with corneal scar due to phlyctenular keratitis. HOAs of the total cornea, and of the anterior and posterior surfaces were measured using anterior segment optical coherence tomography (AS-OCT). Corneal tomographic patterns were classified into five types: increased regular astigmatism, ectasia, asymmetric, flattening and minimal change patterns. The correlation between corneal HOAs and visual acuity was evaluated.

RESULTS

Mean months from onset was 50.7 ± 74.7 and mean number of recurrences 2.1 ± 1.1 (1-5). Mean logarithm of the minimal angle of resolution (logMAR) was 0.19 ± 0.31. AS-OCT showed ectasia pattern in 16 eyes (31.4%), asymmetric pattern in 12 eyes (23.5%), increased regular astigmatism pattern in 9 eyes (17.6%), flattening pattern in 3 eyes (5.9%) and minimal change pattern in 11 eyes (21.6%). HOAs of the total cornea were 0.57 ± 0.44 μm and 1.16 ± 0.77 μm within a 4-mm and 6-mm diameter, significantly larger than in normal controls (P < 0.0001). LogMAR visual acuity was significantly correlated with corneal HOAs (4-mm: r = 0.558, P < 0.0001, 6-mm: r = 0.566, P < 0.0001), central corneal thickness (r = - 0.349, P = 0.016), and corneal astigmatism (r = 0.414, P = 0.004), but not with average keratometric value (r = - 0.092, P = 0.537).

CONCLUSIONS

The most common tomographic pattern was ectasia, followed by a asymmetric pattern in eyes with phlyctenular keratitis. Corneal HOAs were associated with decreased visual acuity in phlyctenular keratitis patients.

Characterization of Meibomian Gland Atrophy and the Potential Risk Factors for Middle Aged to Elderly Patients With Cataracts

Purpose

To explore the characteristics of meibomian gland (MG) atrophy and its potential risk factors in the age-related cataract population.

Methods

Patients who underwent cataract surgery at age 40 or older were enrolled in this study. Preoperative clinical measurement records were obtained, including lipid layer thickness, tear meniscus height, noninvasive breakup time, and meiboscore. The meibomian gland atrophy ratio (MGAR) was measured by the ImageJ software. Univariate regression analysis and multivariate regression analysis were used to analyze the risk factors for MG atrophy.

Results

Female patients had less atrophy of the MG compared with male patients. The MGAR, meiboscore, tear meniscus height (TMH), and lipid layer thickness (LLT) gradually increased with age. However, the noninvasive breakup time decreased with age. The multivariate regression analysis indicated that dyslipidemia and increased triglyceride levels were identified as independent protective factors for MG atrophy. We further stratified the model by sex, and the following results showed only in the female patients with dyslipidemia and increased triglyceride had decreased MG atrophy. No significant correlation was observed between MG atrophy and tear film parameters including TMH, noninvasive breakup time, and LLT.

Conclusions

Our study suggests that age, sex, and diabetes are potential risk factors for MG atrophy. In addition, dyslipidemia and increased triglyceride levels are independent protective factors for MG atrophy in the elderly female population.

Translational Relevance

MG atrophy is the leading cause of meibomian gland dysfunction. To study the characteristics and risk factors of MG atrophy in cataract patients would be helpful to predict and prevent postoperative development of MGD.

Dry anophthalmic socket syndrome - Standardized clinical evaluation of symptoms and signs

OBJECTIVES

To assess symptoms and signs of the dry anophthalmic socket syndrome (DASS) in a standardized manner.

METHODS

87 unilateral anophthalmic patients were evaluated using the Ocular Surface Disease Index (OSDI), the 5-Item Dry Eye Questionnaire (DEQ-5), and a modified version of Symptom Assessment iN Dry Eye (SANDE) questionnaire separately for the anophthalmic socket and for the healthy fellow eye. Conjunctival inflammation was semi-quantitatively graded and Schirmer I test with topical anesthesia was performed bilaterally. The correlations between scores of the dry eye questionnaires and the results of the Schirmer tests, conjunctival inflammation, and demographic data were examined.

RESULTS

Patients had significantly higher OSDI, DEQ-5 and SANDE scores at the anophthalmic side compared to the healthy eye (p ≤ 0.019, respectively). 63% of patients complained of anophthalmic socket dryness in at least one of the three questionnaires. Patients had higher inflammation (p < 0.001) and more tear volume in the Schirmer I test with topical anesthesia (p ≤ 0.024) on the anophthalmic side compared to the fellow eye.

CONCLUSIONS

Most anophthalmic patients have significantly more subjective dryness complaints on their anophthalmic side compared to the healthy fellow eye, even in absence of tear deficiency and clinical blepharitis. Eye care practitioners should consider the diagnosis criteria and the definition for DASS proposed in this study, when counseling anophthalmic patients. However, research should be undertaken to investigate the role and the interactions of causative etiological causes for DASS. Furthermore, there is a high priority to establish a standardized examination protocol and to develop an evidence-based treatment algorithm for DASS.

The Microbiome of the Meibum and Ocular Surface in Healthy Subjects

Purpose

The purpose of this study was to investigate the microbiome in the meibum, conjunctival sac, and eyelid skin in young and elderly healthy subjects, and analyze the effect that age, sex, and region have on microbiome composition.

Methods

This study involved 36 healthy subjects (young-age subjects: 9 men/9 women, age range: 20–35 years; elderly age subjects: 9 men/9 women, age range: 60–70 years). In all subjects, lower-eyelid meibum, lower conjunctival sac, and lower-eyelid skin specimens were collected from one eye, and then stored at –20°C. Taxonomic composition of the microbiome was obtained via 16S rRNA gene sequencing, and then analyzed.

Results

The meibum microbiome showed a high α-diversity (within-community diversity), particularly in the young subjects. However, in approximately 30% of the elderly subjects, a low-diversity microbiome dominated by Corynebacterium sp. or Neisseriaceae was observed. In the young subjects, the microbiome of the meibum resembled that of the conjunctival-sac, yet in the elderly subjects, the microbiome of the conjunctival-sac became more similar to that of the eyelid skin. The eyelid-skin microbiome was relatively simple, and was typically dominated by Propionibacterium acnes in the young subjects, or by Corynebacterium sp. or Neisseriaceae in the elderly subjects. In both age groups, no significant difference was seen between the men and women in regard to the meibum, conjunctival-sac, and eyelid-skin microbiome.

Conclusions

Our findings confirmed that the meibum of healthy adult-age subjects harbors highly diverse microbiota, and revealed that the meibum microbiome, especially the decrease of its diversity, alters with aging and may affect the homeostasis of the ocular surface.

Composition and Diversity of Bacterial Community on the Ocular Surface of Patients With Meibomian Gland Dysfunction

Purpose

To investigate the composition and diversity of bacterial community on the ocular surface of patients with meibomian gland dysfunction (MGD) via 16S rDNA sequencing.

Methods

Forty-seven patients with MGD, who were divided into groups of mild, moderate, and severe MGD, and 42 sex- and age-matched participants without MGD (control group) were enrolled. Samples were collected from the upper and lower conjunctival sac of one randomly chosen eye of each participant. Through sequencing the hypervariable region of 16S rDNA gene obtained from samples, differences in the taxonomy and diversity between groups were compared.

Results

Principle coordinate analysis showed significantly distinct clustering of the conjunctival sac bacterial community between the severe MGD group and the other groups. At the phylum level, the relative abundances of Firmicutes (31.70% vs. 19.67%) and Proteobacteria (27.46% vs. 14.66%) were significantly higher (P < 0.05, Mann-Whitney U), and the abundance of Actinobacteria (34.17% vs. 56.98%) was lower in MGD than controls (P < 0.05, Mann-Whitney U). At the genus level, the abundances of Staphylococcus (20.71% vs. 7.88%) and Sphingomonas (5.73% vs. 0.79%) in patients with MGD were significantly higher than the controls (P < 0.05, Mann-Whitney U), while the abundance of Corynebacterium (20.22% vs. 46.43%) was significantly lower (P < 0.05, Mann-Whitney U). The abundance of Staphylococcus was positively correlated with the meiboscores in patients with MGD (r = 0.650, P < 0.001, Spearman).

Conclusions

Patients with MGD can have various degrees of bacterial microbiota imbalance in the conjunctival sac. Staphylococcus, Corynebacterium, and Sphingomonas may play roles in the pathophysiology of MGD.

Tear Film Instability and Meibomian Gland Dysfunction Correlate with the Pterygium Size and Thickness Pre- and Postexcision in Patients with Pterygium

Purpose

This study aimed to evaluate the effects of excision on dry eye and meibomian gland dysfunction (MGD) in individuals with pterygium, before and after surgery. It also aimed to investigate how these effects correlate with the size and thickness of the pterygium.

Subjects and Methods

63 eyes from 63 patients with primary nasal pterygium and 45 eyes from 45 healthy volunteers without ocular pathologies were enrolled in this study. 63 eyes from 63 patients underwent pterygium surgery. ImageJ software was used to calculate the pterygium size based on images of the anterior segments. Anterior segment spectral domain optical coherence tomography (SD-OCT) was performed preoperatively to measure the thickness of the pterygium 1 mm anterior to the nasal scleral spur. The ocular surface disease index (OSDI), Schirmer I Test (SIT), and MGD grade were used to evaluate the eyes, and the eyes were imaged using the noninvasive keratograph average tear film breakup time (NIBUTav), tear meniscus height (TMH), meiboscore, and lipid layer grading tools of the Oculus® Keratograph 5M, preoperatively and at 1, 3, and 6 months postoperatively.

Results

The OSDI, NIBUTav, lid margin abnormality, meiboscore, and lipid layer grading values differed significantly in the pterygium patients in comparison with the controls (p < 0.01 for all scores). However, the SIT and TMH values were unchanged between the two groups (all p > 0.05). Multivariate regression analysis demonstrated that the NIBUTav, meiboscore, and lipid layer grading score was significantly correlated with the pterygium parameters, such as size and thickness. The postoperative OSDI, NIBUTav, lid margin abnormality, and lipid layer grading values improved significantly (p < 0.05 for all scores). The SIT, TMH, and meiboscore results did not differ significantly between the pre- and postoperative values (p > 0.05). Among the conventional and automated indexes, at 1 month postoperatively, SIT and TMH were significantly correlated with the pterygium parameters, but no correlation was observed at 3 and 6 months postoperatively. The OSDI, NIBUTav, meiboscore, and lipid layer grading values at 1, 3, and 6 months postoperatively were significantly correlated with the pterygium parameters.

Conclusion

Abnormal tear film and meibomian gland (MG) function improved following pterygium excision in the patients with primary pterygium, which was associated with uncomfortable ocular symptoms. Pterygium parameters, such as size and thickness, correlated with the dry eye and MGD indexes in patients pre- and postoperatively, potentially offering a novel strategy for clinical implementation of pterygium excision surgery.

Cyclic Change of Fatty Acid Composition in Meibum During the Menstrual Cycle

Purpose

To evaluate the fatty acid (FA) composition in the meibum of pre- and postmenopausal women and age-matched men.

Methods

This prospective study involved 24 healthy subjects; six premenopausal women in their 30s with a regular menstrual cycle (young-female [yF] group), six postmenopausal women in their 60s (elderly-female [eF] group), and 12 age-matched men (i.e., young-male [yM] and elderly-male [eM] groups, respectively). The menstrual cycle was divided into six phases (phase I–VI). Meibum was obtained from the meibomian gland orifices via a Daviel spoon, and its FA composition was then analyzed via gas chromatography mass spectrometry (GC-MS). Principal component analysis (PCA) was performed on the GC-MS results.

Results

The mean FA composition of all subjects was 40% saturated FAs (SFA) and 60% unsaturated FAs (UFAs). The PCA results of all groups indicated two categories (PC1 [77.5%] and PC2 [12.4%]); one consisting of yF-group samples of mainly phase II and III and the other consisting of the yF-group samples of the rest of the cycle, as well as from eF-group, yM-group, and eM-group samples. Each group had a distinctive nature. The FAs that most contributed to PC1 were C_14:0, C_16:0, and C_18:0 in a positive correlation, and C_18:1n9 in a negative correlation.

Conclusions

FA composition noticeably changes during the menstrual cycle and is somewhat affected by sex and age. The ratio of SFAs (C_16:0, C_18:0) to mono-UFAs (C_18:1n9) in the FA composition might have an impact on the lipid quality of meibum, thus suggesting alteration of its melting temperature and viscosity.

A Novel Automated Approach for Infrared-Based Assessment of Meibomian Gland Morphology

Purpose

We present and validate a new methodology for analyzing, in an automated and objective fashion, infrared images of the meibomian glands (MG).

Methods

The developed algorithm consists of three main steps: selection of the region of interest, detection of MG, and analysis of MG morphometric parameters and dropout area (DOA). Additionally, a new approach to quantify the irregularity of MG is introduced. We recruited 149 adults from a general population. Infrared meibography, using Keratograph 5M, was performed. Images were assessed and graded subjectively (Meiboscore) by two experienced clinicians and objectively with the proposed automated method.

Results

The correlation of subjective DOA assessment between the two clinicians was poor and the average percentage of DOA estimated objectively for each Meiboscore group did not lie within their limits. The objective assessment showed lower variability of meibography grading than that obtained subjectively. Additionally, a new grading scale of MG DOA that reduces intraclass variation is proposed. Reported values of MG length and width were inversely proportional to the DOA. Gland irregularity was objectively quantified.

Conclusions

The proposed automatic and objective method provides accurate estimates of the DOA as well as additional morphologic parameters that could add valuable information in MG dysfunction understanding and diagnosis.

Translational Relevance

This approach highlights the shortcomings of currently used subjective methods, and provides the clinicians with an objective, quantitative and less variable alternative for assessing MG in a noninvasive and automated fashion. It provides a viable alternative to more time-consuming subjective methods.

Evaluation of ocular surface impairment in meibomian gland dysfunction of varying severity using a comprehensive grading scale

This study aimed to propose a comprehensive grading scale to evaluate different clinical manifestations in patients with varying severity of meibomian gland dysfunction (MGD) and analyze the correlations between the parameters of ocular surface impairment in MGD.A total of 63 patients with MGD were enrolled. Ten specific symptoms were evaluated each with a subjective score and total score was applied to grade the severity of MGD. Thirty-seven patients were diagnosed with mild, 19 with moderate, and 7 with severe MGD. Slit-lamp and keratography were used to assess the signs of ocular surface and meibomian gland (MG). In vivo confocal microscopy (IVCM) was performed to evaluate the corneal nerves and dendritic cells. The differences and correlations between symptoms, signs, and IVCM parameters were analyzed.Dryness, foreign body sensation, asthenopia, and photophobia were the most common and severe symptoms in our patients. The severe MGD group showed worse MG expressibility, Meibum score, Meiboscore, MG score, and higher nerve reflectivity (P < .05). The mild MGD group showed higher nerve density (P < .05). Total symptom score was negatively correlated with nerve density (r = -0.374, P < .05), while positively correlated with nerve reflectivity and dendritic cell density (r = 0.332 and 0.288, respectively, P < .05). MG score was correlated with nerve reflectivity (r = 0.265, P < .05).The comprehensive grading scale was suitable for evaluating clinical manifestations in MGD of varying severity. The relationship between the specific symptoms, signs, and IVCM results concerning whole ocular surface impairment could help elucidate MGD pathophysiology and benefit evaluation or treatment in the future.

Clinically Relevant Immune-Cellular Metrics of Inflammation in Meibomian Gland Dysfunction

Purpose

To determine the reliability and clinical relevance of in vivo confocal microscopy (IVCM)-based immune-cellular metrics of palpebral conjunctival inflammation in meibomian gland dysfunction (MGD).

Methods

Sixteen MGD patients and 13 reference controls included in this cross-sectional, retrospective study, had an ocular surface exam, symptom assessment (Ocular Surface Disease Index questionnaire [OSDI]), and palpebral conjunctival IVCM imaging. Bland-Altman analyses, intraclass correlation coefficient (ICC_a), Lin's concordance correlation coefficient (ρ_c), receiver operating characteristic (ROC) analyses, and correlations were performed. Clinical outcome measures were symptom severity (OSDI scores), tear break-up time (TBUT), and corneal fluorescein staining (CFS grade).

Results

Compared to controls, patients with MGD had variable symptom severity (average OSDI score: 48.3 ± 7.6, P = 0.0008, range: 8.3–85.42), shorter TBUT (6.8 ± 0.9 seconds, P = 0.002), comparable corneal staining (0.31 ± 0.19, P = 0.20), and greater conjunctival inflammation (epithelial immune cells [EIC]: 477.8 ± 54.2 vs. 123.3 ± 17.2 cells/mm², P < 0.0001; intraglandular immune cells [IGIC]: 41.9 ± 3.3% vs. 20.33 ± 7.3%, P < 0.01). Immune-cellular metrics had high inter- and intraobserver agreement (ρ_c: 0.86–0.94; ICC_a and Cronbach's α: 0.85–0.97, P < 0.0001). EIC correlated positively with OSDI (r_s: 0.49, P = 0.03), while both EIC and IGIC correlated inversely with TBUT (r_s: −0.47, −0.45, P < 0.05), and had high accuracy in detecting inflammation (ROC area under the curve [AUC]: 0.97 and 0.89, P ≤ 0.001).

Conclusions

EIC and IGIC are increased in highly symptomatic patients with MGD that have minimal corneal staining, and correlate with symptoms and clinical signs. EIC and IGIC may provide reliable and clinically relevant metrics of inflammation.

Prediction of potential drugs and targets based on meibomian gland dysfunction module classification to guide individualized treatment

Meibomian gland dysfunction (MGD) is an epidemic chronic ocular inflammation. However, little is known about its effective treatment. Here, this study identified important MGD-related genes, core regulators, and potential drugs and their targets though integrating a series of bioinformational analyses. First, there were 665 differentially expression genes (DEGs) were identified. Then, 56 coexpression modules were exacted based on the expression of DEGs and their interactors. Moreover, core transcription factors (TF) significantly regulated modules were identified, including RELA, HIF1A, SIRT1, and MYC, which related to variety of eye diseases. Finally, the prediction of potential drugs and the identification of their target were performed. The results showed that artenimol, copper, and glutathione may have the remarkable curative effect or the toxicology to MGD. Moreover, their targets module gene LDHA (lactate dehydrogenase A), ENO1 (enolase 1), ALB (albumin), and PKM (pyruvate kinase M) are play important role in eye diseases. It suggests that these potential drugs may be useful for the treatment of MGD by acting on their targets. It provides valuable references for drug redirection and new drug development for drug developers, and provides individualized treatment strategies for tarsal gland dysfunction.

Inflamed Obstructive Meibomian Gland Dysfunction Causes Ocular Surface Inflammation

Meibomian gland dysfunction (MGD) is one of the primary causes of evaporative dry eye. Stagnation of meibum induces an unstable tear film, thus resulting in shortened tear film breakup time and superficial punctate keratopathy (SPK) in the lower cornea and punctate staining of lower bulbar conjunctiva. MGD is sometimes accompanied with inflammation (termed "meibomitis") via the proliferation of bacteria in the meibomian gland and eyelash area. Meibomitis is strongly related to ocular surface inflammation such as corneal cellular infiltrates and neovascularization, SPK, and conjunctivitis. It is difficult to differentiate SPK caused by dry eye from that caused by meibomitis. When clinicians are unaware of the existence of meibomitis, and only aware of SPK on the cornea, they often try to treat SPK as it is caused by dry eye using dry eye-specific eyedrops or even using punctual plugs when conservative therapy is ineffective. However, even when intensive dry eye therapy is applied, it may be unsuccessful until SPK caused by meibomitis is recognized and treated with systemic antimicrobial agents. Hence, the tear secreting glands, including the meibomian glands, and the ocular surface should be clinically considered as one unit (i.e., the meibomian gland and ocular surface [MOS]) when considering the pathophysiology and treatment of ocular surface inflammatory diseases (i.e., corneal epithelial damage). Following this clinical pathway, a treatment focusing on meibomian gland inflammation may be a more reasonable approach for meibomitis-related or associated keratoconjunctivitis to more effectively treat this ocular surface disease.

Evaluation of the ocular surface characteristics and Demodex infestation in paediatric and adult blepharokeratoconjunctivitis

BACKGROUND

To evaluate the ocular surface characteristics and the infestation of Demodex in Chinese paediatric and adult blepharokeratoconjunctivitis (BKC).

METHODS

Fifty consecutive patients with BKC and 50 age- and sex-matched healthy subjects were enrolled. Lid margin characteristics and corneal disorders were evaluated under slit-lamp illumination. Four eyelashes were collected from each eye to examine Demodex infestation by light microscopy.

RESULTS

Corneal neovascularization (P = 0.001) and scarring (P = 0.040) were significantly worse in children than in adults with BKC, whereas meibum quality was worse in adults (P = 0.008). Diagnosis delay was longer in children with BKC than in adults (2.2 vs 1.2 years, P = 0.022). Demodex infestation was more frequent in subjects with BKC than in healthy subjects (56% vs 26%, P = 0.002). The lid margin inflammation and meibomian gland dysfunction were worse in Demodex-positive subjects than in Demodex-negative subjects with BKC.

CONCLUSIONS

Children with BKC had severer corneal disorders compared with adult BKC patients, which may be caused by a long-delayed diagnosis. Ocular demodicosis was more common in subjects with BKC. Ocular Demodex infestation was associated with worse lid margin inflammation and meibomian gland dysfunction.

Ocular surface pathogenesis associated with precocious eyelid opening and necrotic autologous tissue in mouse with disruption of Prickle 1 gene

Ocular surface disease is one major type of eye diseases. Different etiologies trigger distinct pathological responses of the ocular surface. We previously reported that genetically engineered mice with ablation of Prickle 1 manifested precocious eyelid opening with ensuing cornea dysplasia. The current study aimed to characterize the molecular traits and the direct cause of ocular pathology associated with precocious eyelid opening in the Prickle 1 mutant mouse. Prickle 1 mutant mice exhibited a slew of ocular surface pathology including cell proliferation, cell fate transformation and inflammatory infiltration coinciding with the timing of the precocious eyelid opening. Forced eyelid opening in wild type mice did not induce cornea pathology comparable to that of the Prickle 1 mutants. Necrotic tissue debris was found associated with the lesioned cornea. RNAseq analysis of the mutant cornea revealed an expression profile shared by a range of dermatological diseases involving immune responses and cancer. Taken together, the data suggest that the necrotic eyelid debris plays an important role in ocular pathogenesis of the Prickle 1 mutant mouse, which may represent a type of non-infectious keratoconjunctivitis caused by damaged autologous tissues. Additionally, Prickle 1 mutant cornea pathogenesis may offer molecular insights into other types of epithelial pathogenesis.

Assessment of Ocular Surface Damage during the Course of Type 2 Diabetes Mellitus

Purpose

To investigate the impact of disease duration on the ocular surface during the course of type 2 diabetes mellitus compared with nondiabetic controls.

Methods

One hundred twenty diabetic patients were divided into three groups according to disease duration: less than 5 years, 5–10 years, and over 10 years. All eyes were imaged using a corneal topographer (Oculus Keratograph 5M). Tear film measurements and meibography were also recorded. Meibomian gland changes were scored from 0 to 6 (meiboscore).

Results

The noninvasive breakup time first (NIKBUT-1st) and noninvasive breakup time average (NIKBUT-avg) were significantly shorter in the over 10 years diabetic group compared with the control group (P=0.0056  and  P=0.010, resp.). Tear meniscus height (TMH) was significantly lower in the over 10 years diabetic group compared with the control group (P=0.0016) and the 5 years group (P=0.0061). We also found that more patients in the over 10 years diabetic group showed bulbar and limbal hyperemia compared with the control group (bulbar hyperemia: P=0.049; limbal hyperemia: P=0.026). The meiboscore in the over 10 years diabetic group was significantly higher compared with the other three groups (P < 0.05). Bulbar hyperemia showed a significant negative correlation with NIKBUT-1st in the over 10 years diabetic group (r=−0.35  and  P < 0.05).

Conclusion

Ocular surface damage in long-term type 2 diabetes is more severe than that in patients with shorter disease duration.

Topical Tacrolimus 0.03% for Maintenance Therapy in Steroid-Dependent, Recurrent Phlyctenular Keratoconjunctivitis

PURPOSE

To evaluate the efficacy of topical tacrolimus 0.03% as steroid-free maintenance therapy in young patients with severe, recurrent phlyctenular keratoconjunctivitis (PKC).

METHODS

The medical records of 6 eyes of 5 patients (4 children and 1 young adult) with recurrent, steroid-dependent PKC were reviewed. The patients were treated with combined application of topical steroids and tacrolimus 0.03% in the active phase and maintained on topical tacrolimus alone after remission.

RESULTS

The clinical signs, symptoms, and visual acuities resolved in all patients after 25.2 ± 16.9 days of combined treatment with steroids and tacrolimus. After disease remission, the patients were maintained on topical tacrolimus 0.03% once daily alone for 8.4 ± 4.7 months, and no recurrence occurred during 10.6 ± 1.9 months of follow-up. Tacrolimus was successfully discontinued in 2 patients without further recurrence. There were no ocular side effects related to the use of topical tacrolimus.

CONCLUSIONS

Topical tacrolimus 0.03% was effective in maintaining long-term remission in patients with recurrent, steroid-dependent PKC.