In vivo confocal microscopy of bulbar conjunctiva in patients with Graves' ophthalmopathy

A review of the application of in-vivo confocal microscopy on conjunctival diseases

Over the past few decades, the expanded applications of in-vivo confocal microscopy (IVCM) have greatly enhanced the knowledge of a variety of conjunctival diseases. IVCM allows non-invasively detailed observation of tarsal, palpebral and bulbar conjunctiva, from the superficial to the substantia propria at the cellular level. IVCM has been shown as a powerful tool for the assessment of morphological changes in both physiological and pathological conditions. High-resolution images of different cellular phenotypes, together with quantifiable results, open new insights into understanding the mechanisms of conjunctival diseases, as well as provide valuable and longitudinal information for the diagnosis and therapeutic evaluation. This review aims to provide an overview of the current knowledge on the applications of IVCM on conjunctival disorders, including aging changes, dry eye-related morphological changes, glaucoma and glaucoma surgery-related morphological changes, conjunctival neoplasm, pterygium, allergic conjunctivitis, trachomatous scarring, and the conjunctiva-associated lymphoid tissue (CALT) changes. In this review, we highlight the key findings of previous studies and discusses the current limitations and challenges of IVCM in assessing the structural characteristics of the conjunctiva. Furthermore, we consider possible future directions for unlocking the full potential of IVCM applications. The insights presented here will contribute to a more comprehensive understanding of the applications of IVCM in conjunctival diseases.

Risk Factors for Ocular Surface Irritation Symptoms in Inactive Mild and Moderate-to-Severe Graves' Orbitopathy

INTRODUCTION

This study aims to analyze risk factors for ocular surface irritation symptoms in patients with non-corneal-damage inactive mild and moderate-to-severe Graves' orbitopathy (GO).

METHODS

This retrospective study enrolled 307 patients with non-corneal-damage inactive GO admitted to Sun Yat-sen Memorial Hospital from April 2017 to September 2023. The activity and severity of GO were evaluated using the Clinical Activity Score (CAS) and the European Group on Graves' Orbitopathy (EUGOGO) classification, respectively. Multivariate logistic regression analysis was performed to analyze risk factors for ocular surface irritation symptoms.

RESULTS

Among patients with inactive GO, for mild cases, CAS (P < 0.001), upper eyelid lag (P = 0.049), and extraocular muscle involvement (P = 0.019) in the symptomatic group were greater than those in the asymptomatic group, and multivariate logistic regression analysis demonstrated that upper eyelid lag (P = 0.048), CAS 1 (P < 0.001), CAS 2 (P = 0.005), and extraocular muscle involvement (P = 0.029) were risk factors for ocular surface irritation symptoms; for moderate-to-severe cases, CAS (P = 0.004), extraocular muscle involvement (P < 0.001), marginal reflex distance 1 (MRD1) (P = 0.030), and thyroid-stimulating hormone (TSH) (P = 0.034) in the symptomatic group were greater than those in the asymptomatic group, while multivariate logistic regression analysis indicated that extraocular muscle involvement (P = 0.018) and MRD1 (P = 0.012) were risk factors for ocular surface irritation symptoms.

CONCLUSION

In non-corneal-damage inactive mild and moderate-to-severe GO, eyelid malposition and periocular muscle inflammation are risk factors for ocular surface irritation symptoms.

Neurophysiology of corneal neuropathic pain and emerging pharmacotherapeutics

The altered activity generated by corneal neuronal injury can result in morphological and physiological changes in the architecture of synaptic connections in the nervous system. These changes can alter the sensitivity of neurons (both second-order and higher-order projection) projecting pain signals. A complex process involving different cell types, molecules, nerves, dendritic cells, neurokines, neuropeptides, and axon guidance molecules causes a high level of sensory rearrangement, which is germane to all the phases in the pathomechanism of corneal neuropathic pain. Immune cells migrating to the region of nerve injury assist in pain generation by secreting neurokines that ensure nerve depolarization. Furthermore, excitability in the central pain pathway is perpetuated by local activation of microglia in the trigeminal ganglion and alterations of the descending inhibitory modulation for corneal pain arriving from central nervous system. Corneal neuropathic pain may be facilitated by dysfunctional structures in the central somatosensory nervous system due to a lesion, altered synaptogenesis, or genetic abnormality. Understanding these important pathways will provide novel therapeutic insight.

Investigation of Conjunctival Goblet Cell and Tear MUC5AC Protein in Patients With Graves' Ophthalmopathy

Purpose

The aim of this study was to investigate conjunctival goblet cell density (GCD) and tear mucin-5AC (MUC5AC) protein levels in patients with Graves' ophthalmopathy (GO) and their association with dry eye indicators.

Methods

A total of 99 patients with GO (54 active, 45 inactive) and 40 healthy controls were recruited. Comprehensive ophthalmic examinations, including the external eye, ocular surface, GCD, and tear MUC5AC ELISA, were performed. The GCD examination was performed in temporal bulbar conjunctiva, including IVCM GCD by in vivo confocal microscopy (IVCM) and filled GCD of cytokeratin-7 and MUC5AC-positive co-immunomarkers by impression cytology. Tear MUC5AC protein was detected using samples extracted from Schirmer strips.

Results

The GO group showed a significant decrease in IVCM GCD, filled GCD, and normalized tear MUC5AC protein compared to controls, with the active GO group showing the greatest decrease (all P < 0.05). Tear MUC5AC protein levels in GO correlated with those of IVCM GCD (r = 0.40, P < 0.001) and filled GCD (r = 0.54, P < 0.001, respectively). Higher ocular surface disease index (r = -0.22, P < 0.05; r = -0.20, P < 0.05; r = -0.21, P < 0.05) and lisamine green staining (r = -0.23, P < 0.05; r = -0.38, P < 0.001; r = -0.42, P < 0.001) were associated with lower tear MUC5AC protein levels, IVCM GCD, and filled GCD, respectively, which decreased with increasing clinical activity score (r = -0.24, P < 0.05; r = -0.28, P < 0.01; r = -0.27, P < 0.01) and conjunctival congestion score (r = -0.27, P < 0.01; r = -0.33, P < 0.001; r = -0.42, P < 0.001).

Conclusions

The goblet cell count and tear MUC5AC protein in GO eyes were decreased, possibly due to ocular surface inflammation.

Translational Relevance

This study observed the change of tear film mucin in GO patients.

Risk factors for development of superior limbic keratoconjunctivitis in thyroid eye disease in Japanese

PURPOSE

To analyse risk factors for the development of superior limbic keratoconjunctivitis (SLK) in thyroid eye disease (TED).

METHODS

This prospective, observational study included 638 eyes/sides from 319 patients with TED. The eyes were classified into two groups, based on the presence and absence of SLK. Multivariate logistic regression analysis was performed to evaluate potential risk factors, including sex, patient age, past treatment history (steroid, orbital radiotherapy and radioiodine therapy), smoking, clinical activity score, margin reflex distance (MRD)-1 and -2, Graefe sign/lid lag, Hertel exophthalmometric results, Schirmer's test results, tear break-up time (TBUT) and tear meniscus height (TMH).

RESULTS

SLK was found in 198 eyes (31.0%) from 121 patients. Young age (OR, 0.977; P = 0.006), smoker (OR, 1.785; P = 0.009), presence of Graefe sign (OR, 2.912; P < 0.001), absence of lid lag (OR, 0.485; P = 0.031), high Hertel exophthalmometric values (OR, 1.125; P = 0.002), shorter Schirmer's test results (OR, 0.962; P < 0.001), shorter TBUT (OR, 0.815; P = 0.002) and high upper TMH (OR, 1.003; P = 0.013) were associated with the development of SLK. A high MRD-1 measurement value also tended to be associated with a risk of SLK, with an OR of 1.187 (P = 0.056).

CONCLUSION

The present study proposed several risk factors in relation to the development of SLK in TED.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

A clinical study of topical treatment for thyroid-associated ophthalmopathy with dry eye syndrome

INTRODUCTION

Clinically, thyroid-associated ophthalmopathy (TAO) patients were suffered from dry eye syndrome. Only a few relevant studies were about this topic. Our study was determined to provide high-level evidence for the treatment of TAO with dry eye syndrome.

PURPOSE

To compare the clinical effects of vitamin A palmitate eye gel and sodium hyaluronate eye drop forTAO patients with dry eye syndrome.

METHODS

The study was conducted in the Ophthalmology Department of the Ninth People's Hospital Affiliated with the Medical College of Shanghai Jiao Tong University from May to October 2020. A total of 80 mild or moderate-to-severe TAO patients with dry eye syndrome were randomly divided into two groups. The disease stages of all subjects were inactive. Patients in group A were treated with vitamin A palmitate eye gel three times/day for one month and sodium hyaluronate eye drop in group B. The index including break-up time (BUT) and Schirmer I test (ST), corneal fluorescence staining (FL), ocular surface disease index (OSDI), and adverse reactions were recorded by the same clinician at baseline and 1 month after treatment. The data were analyzed by SPSS 24.0.

RESULTS

Finally, 65 subjects completed the treatment. The average age of the patients in Group A was 38.1 ± 11.4 years, and that in Group B was 37.26 ± 10.67 years. 82% of the subjects in group A were female and 74% in group B. There was no significant difference between the two groups at baseline, including the value of ST, BUT, OSDI, and FL grade. After the treatment, the effective rate was 91.2% in group A, of which the value of BUT and FL grade was significantly improved (P < 0.001). The effective rate in group B was 67.7%, of which the value of OSDI score and FL grade was significantly improved (P = 0.002). In addition, the BUT value of group A was significantly longer than that of group B (P = 0.009).

CONCLUSION

InTAO patients with dry eye syndrome, vitamin A palmitate gel and sodium hyaluronate eye drop improved the dry eye and promoted corneal epithelial repair. Vitamin A palmitate gel improves the stability of tear film, while sodium hyaluronate eye drop improves patients' subjective discomfort.

Ocular surface and the upper eyelid contour after surgical treatment of upper eyelid retraction in thyroid eye disease

BACKGROUND: Most of the thyroid eye disease (TED) patients have dry eye syndrome. Upper eyelid retraction (UER) is the most common TED symptom and one of dry eye causes. There are two groups of UER surgical treatment methods: transconjunctival and transcutaneous, which can influence on upper eyelid contour, tear film and ocular surface. AIM: To evaluate the influence of different methods of UER surgery on upper eyelid contour and ocular surface. MATERIALS AND METHODS: 12 patients (19 eyes) were included in the study. Visual acuity test, measurements of UER and palpebral fissure height, Shirmer 1 test, LIPCOF-test and tear break-up time test, Meibomian gland dysfunction staging, corneal and conjunctival fluorescein staining and determination of the ocular surface disease index (OSDI) were performed before surgery and 1 week, 1 and 3 months after. Patients were divided into two groups. Patients of group 1 had UER less than 4 mm and they underwent an upper tarsal muscle extirpation. Patients of group 2 had UER 4 mm and more and they underwent a recession of the levator palpebrae superioris muscle apouneurosis. RESULTS: In all patients UER and the height of the palpebral fissure decreased 7 days after surgery and increased again after 3 months, and the dynamics of this change was more pronounced in group 2. There was one patient (both sides) with poor upper eyelid contour after surgery in both groups. BCVA and OSDI improved, while other parameters had a large scatter of data. CONCLUSIONS: We have found that surgical treatment of UER caused by TED improves the contour of the eyelid, increases visual acuity and leads to a subjective improvement in the condition of the ocular surface.

Changes in Dry Eye Status after Steroid Pulse and Orbital Radiation Therapies in Active Thyroid Eye Disease

This prospective, observational study examined changes in dry eye status after steroid pulse and orbital radiation therapies in 16 patients (32 eyes) with active thyroid eye disease (TED). TED status was evaluated through clinical activity score (CAS), margin reflex distance (MRD)-1 and 2, presence or absence of Graefe’s sign/lid lag, and Hertel exophthalmometric value. Dry eye status was quantified through presence or absence of superior limbic keratoconjunctivitis, corneal fluorescein staining (AD score), tear break-up time, Schirmer test I results, tear meniscus height, and dry eye-related quality of life score. Meibomian gland dysfunction (MGD) was evaluated through Marx line score, eyelid abnormalities (MGD score), meibum expression score, and meibomian gland loss score. Those items were measured before and 6 months after treatment, and the results were statistically compared. Consequently, CAS significantly improved, and MRD-1 significantly decreased after treatment (p < 0.050). Although a part of MGD status improved (p < 0.050), all items regarding dry eye status did not change significantly after treatment (p > 0.050). Steroid pulse and orbital radiation therapies did not largely alter most items regarding dry eye and MGD status.

Improvement of Ocular Surface Disease by Lateral Tarsoconjunctival Flap in Thyroid-Associated Orbitopathy Patients with Lid Retraction

There is a high incidence of ocular surface disease (OSD) in thyroid-associated orbitopathy (TAO) patients as a result of incomplete eyelid closure and chronic inflammatory eyelid status. This study was performed to evaluate the efficacy of a lateral tarsoconjunctival flap (LTF) in improving OSD in TAO patients from the perspective of correcting eyelid closures. As a study design, TAO patients were enrolled in this study to evaluate OSD perioperatively before they were scheduled for LTF surgery. Additional lid surgery was also recorded. The outcome was evaluated with perioperative OSD measurements and tear inflammatory mediators at baseline and one month and three months postoperatively. As a result, 42 patients (5 male, 37 female) underwent LTF surgery, and 13 patients received medial pretarsal support with collagen grafts. Eleven patients underwent blepharotomy, and 6 patients received Botox injections for upper lid retraction. The mean age of the participants was 46.4 years old, and the mean follow-up period was 10.6 months. Their clinical activity score (CAS) at the time of the operation was 2.1. Dry eye parameters, such as ocular surface disease index, tear breakup time, Schirmer’s I test score, and meibomian gland dropout were all significantly improved 3 months postoperatively. Tear osmolarity and inflammatory mediators in tear fluid, such as IL-6, IL-8, IL-18 and MCP-1, were also significantly improved after the procedures. After the surgery, all complications were mild and temporary. As a conclusion, LTF could provide TAO patients with both lid retraction correction and improvement of ocular surface disorders. Dry eye parameters significantly improved 3 months postoperatively. This method can serve as an alternative treatment option for lid correction in TAO patients.

Ocular manifestations of endocrine disorders

Endocrinopathies are prevalent diseases that typically affect multiple organs, and the eye and orbital tissues are often involved in endocrine disorders. Some conditions, such as diabetes and thyroid gland dysfunction, may cause serious eye pathology and even blindness. A clear insight into the pathogenesis of endocrinopathies and their ocular manifestations would enhance preventive and therapeutic measures and reduce the incidence of sight-threatening complications. This review discusses the ocular manifestations of several endocrine disorders that eye care providers are likely to encounter in clinical practice.

Evaluation of Meibomian Gland Loss and Ocular Surface Changes in Patients with Mild and Moderate-to-Severe Graves' Ophthalmopathy

OBJECTIVES

To evaluate the association of Graves' Ophthalmopathy (GO) with the meibomian glands and investigate the relation of ocular surface changes with meibomian gland parameters in patients with GO.

METHODS

This prospective study included 44 eyes of 44 mild and moderate-to-severe GO patients and 38 eyes of 38 control subjects. After a complete ophthalmologic examination, patients were assessed according to the Clinical Activity Score (CAS). The area of meibomian gland loss and meibography score was evaluated using meibography (Sirius; CSO, Florence, Italy). Schirmer test, tear break-up time (TBUT) and Ocular Surface Disease Index (OSDI) scores were evaluated.

RESULTS

Mean meibomian gland dropout area was 26.29 ± 1.58% in the GO group and 14.46 ± 1.52% in the healthy controls (p < .001). Mean meibography score in the GO group was 2.61 ± 0.15 while it was 1.32 ± 0.25 in the healthy controls (p < .001). Meibomian gland dropout area was positively correlated with CAS and OSDI questionnaire results (p = .015, r = 0.391; p < .001, r = 0.662, respectively) and negatively correlated with TBUT and Schirmer test scores (p < .001, r = -0.635; p = .003, r = -0.474, respectively). Meibography score was positively correlated with CAS and OSDI questionnaire results (p = .012, r = 0.383; p = .007, r = 0.419, respectively) and negatively correlated with TBUT and Schirmer test scores (p = .002, r = -0.467; p = .023, r = -0.359, respectively).

CONCLUSION

Meibomian glands are quantitatively decreased in patients with GO. The decrease of meibomian glands is correlated with objective and subjective dry eye findings. Dry eye treatment in GO patients should include meibomian gland deficiency as well.

In vivo confocal microscopy assessment of meibomian glands microstructure in patients with Graves' orbitopathy

BACKGROUND

To evaluate microstructural changes in the meibomian glands (MGs) in patients with active and inactive Graves' orbitopathy (GO), using in vivo confocal microscopy (IVCM), and to investigate the correlations between clinical and confocal findings.

METHODS

Forty patients (80 eyes) with GO (34 eyes with active GO, 46 eyes with inactive GO), and 31 age- and sex-matched control participants (62 eyes) were enrolled consecutively. A researcher recorded the clinical activity score (CAS) for each patient. A complete ophthalmic examination was then performed, including external eye, ocular surface and MGs. IVCM of the MGs was performed to determine the MG acinar density (MAD), MG longest and shortest diameters (MALD and MASD), MG orifice area (MOA), MG acinar irregularity (MAI), meibum secretion reflectivity (MSR), acinar wall inhomogeneity (AWI), acinar periglandular interstices inhomogeneity (API), and severity of MG fibrosis (MF).

RESULTS

All confocal microscopy assessments of MGs significantly differed among groups (all P = 0.000). Compared to controls, GO groups showed lower MOA (1985.82 ± 1325.30 μm2 in active GO and 2021.59 ± 1367.45 μm2 in inactive GO vs. 3896.63 ± 891.90 μm2 in controls, all P = 0.000) and MAD (87.21 ± 32.69 /mm2 in active GO and 80.72 ± 35.54 /mm2 in inactive GO vs. 114.69 ± 34.90 /mm2 in controls, P = 0.001 and 0.000, respectively); greater MALD (118.11 ± 30.23 μm in active GO and 120.58 ± 27.64 μm in inactive GO vs. 58.68 ± 20.28 μm in controls, all P = 0.000) and MASD (44.77 ± 19.16 μm in active GO and 46.02 ± 20.70 μm in inactive GO vs. 27.80 ± 9.90 μm in controls, all P = 0.000); and higher degrees of MAI, MSR, and MF (all P<0.05). Eyes with active GO had higher degrees of MAI (P = 0.015), AWI (P = 0.000), and API (P = 0.000), while eyes with inactive GO had higher degrees of MSR (P = 0.000) and MF (P = 0.017). In GO groups, AWI and API were positively correlated with CAS (r = 0.640, P = 0.000; r = 0.683, P = 0.000, respectively), and MF was negatively correlated with CAS (r = - 0.228, P = 0.042).

CONCLUSIONS

IVCM effectively revealed microstructural changes of MGs in eyes with GO and provided strong in vivo evidence for the roles of obstruction and inflammation in the ocular surface disease process. Furthermore, it revealed discernible patterns of MG abnormalities in eyes with active GO and inactive GO, which are not easily distinguishable by typical clinical examinations.

Ocular Surface Changes in Patients with Thyroid Eye Disease: An Observational Clinical Study

Background

This study aimed to compare ocular surface parameter changes in active and inactive thyroid eye disease (TED) patients and controls.

Methods

This is an observational clinical study that included 60 eyes divided into three groups following clinical activity score (CAS) assessment. The first group (Group A) comprised 20 eyes with active TED (CAS score ≥3/7), while the second group (Group B) comprised 20 eyes with inactive TED (CAS score <3/7) and the third group (Group C) comprised 20 eyes of controls without dry eye manifestations. The palpebral fissure height, degree of proptosis, degree of lagophthalmos, ocular surface disease index (OSDI), Schirmer test without anesthesia, corneal fluorescein staining (CFS), non-invasive tear break-up time (NITBUT), tear meniscus height (TMH), lipid layer thickness (LLT), meiboscore, meibomian gland dysfunction (MGD), and thyroid antibodies were assessed and data were compared between study participants.

Results

The mean OSDI was 40.0 ±5.80 in Group A, which significantly differed from Group B with a mean of 26.5 ±5.10 (p=0.02). There were significant differences between the two groups regarding palpebral fissure height (p=0.02), amount of proptosis (p=0.008), and degree of lagophthalmos (p=0.001). Similarly, active TED patients had more decreased tear secretion than inactive TED patients (p=0.012). Moreover, active TED patients showed a significant increase in Meibomian gland loss areas in both upper and lower eyelids compared with inactive TED patients (p=0.001). Corneal fluorescein staining also revealed a statistically significant difference between the studied groups (p=0.0001).

Conclusion

This study showed differences regarding ocular surface parameter changes between both active and inactive TED and compared to controls. Further studies are needed to confirm these results.

Ocular surface changes in Graves' ophthalmopathy

Many patients with Graves' ophthalmopathy (GO) suffer from dry eye syndrome (DES), and this is one of the most common reasons of eye discomfort in patients with GO. The prevalence of DES in patients with GO is significantly higher than normal subjects. The ocular surface changes involving changes in tears, cornea, conjunctiva and glands occur in GO patients. However, the mechanism of how DES occurs in GO still remains unclear. In this review, the ocular surface changes were illustrated and analyzed the reasons for high prevalence of DES in GO patients.

Critical role of mass spectrometry proteomics in tear biomarker discovery for multifactorial ocular diseases (Review)

The tear film is a layer of body fluid that maintains the homeostasis of the ocular surface. The superior accessibility of tears and the presence of a high concentration of functional proteins make tears a potential medium for the discovery of non-invasive biomarkers in ocular diseases. Recent advances in mass spectrometry (MS) have enabled determination of an in-depth proteome profile, improved sensitivity, faster acquisition speed, proven variety of acquisition methods, and identification of disease biomarkers previously lacking in the field of ophthalmology. The use of MS allows efficient discovery of tear proteins, generation of reproducible results, and, more importantly, determines changes of protein quantity and post-translation modifications in microliter samples. The present review compared techniques for tear collection, sample preparation, and acquisition applied for the discovery of tear protein markers in normal subjects and multifactorial conditions, including dry eye syndrome, diabetic retinopathy, thyroid eye disease and primary open-angle glaucoma, which require an early diagnosis for treatment. It also summarized the contribution of MS to early discovery by means of disease-related protein markers in tear fluid and the potential for transformation of the tear MS-based proteome to antibody-based assay for future clinical application.

Bulbar Conjunctival Microvascular Alterations in Thyroid-Associated Ophthalmopathy Patients with Different Activities

Purpose: To evaluate the morphologic and hemodynamic changes of bulbar conjunctival vessels in thyroid-associated ophthalmopathy (TAO) patients and the correlations with the activity.Methods: Patients diagnosed as TAO with different clinical activity scores (CAS) and healthy participants were recruited. All subjects underwent a complete ophthalmic examination and functional slit-lamp biomicroscope. Vascular variables including the vessel density, vessel complexity, average diameter, blood flow velocity and blood flow rate in microvascular networks were measured. The correlations among microvascular parameters, CAS and exophthalmos were analyzed. Areas under the receiver operating characteristic curves (AUROCs) were applied to evaluate the diagnostic accuracy of microvascular alterations for active TAO.Results: A total of 46 eyes were enrolled in our study. The vessel complexity and blood flow velocity increased in the active TAO group significantly compared with the inactive group and healthy controls (P < .05). Meanwhile, the vessel complexity and blood flow rate were positively correlated with CAS (r = 0.641 and r = 0.526). Bulbar conjunctival microvascular parameters performed a good ability in distinguishing the active stage of TAO (AUROC = 0.793).Conclusions: Increasing bulbar conjunctival vessel complexity and blood flow were evident in TAO with severe inflammation. The measurements of bulbar conjunctival microvasculature could be a reference to evaluate activity in TAO.

Prevalence of thyroid eye disease in Graves' disease: A meta-analysis and systematic review

OBJECTIVE

Thyroid eye disease (TED) is a debilitating condition that frequently manifests in patients suffering from Graves' disease (GD). This study aims to analyse the prevalence of TED among GD patients, with a focus on geographical region-specific rates.

METHODS

Medline and Embase were searched for articles examining TED prevalence on April 2020, and articles were retrieved and sieved. Statistical analysis was performed after Freeman-Tukey double arcsine transformation. Thereafter, results were pooled with random effects by DerSimonian and Laird model.

RESULTS

Fifty-seven articles involving 26,804 patients were included in the review. The overall pooled prevalence of TED was 40% (CI: 0.32 to 0.48) and by continent was 38% (CI: 0.31 to 0.46) for Europe, 44% (CI: 0.32 to 0.56) for Asia, 27% (CI: 0.06 to 0.56) for North America and 58% (CI: 0.55 to 0.61) for Oceania. The prevalence of TED in Southeast Asia was 35% (CI: 0.24 to 0.47) and Middle East 48% (CI: 0.19 to 0.78). Subgroup analysis showed regions with predominantly Caucasians (37%; CI: 0.28 to 0.46) had a lower prevalence of TED compared to Asians (45%; CI: 0.33 to 0.58). The pooled prevalence of lid retraction was 57% (CI: 0.39 to 0.74), proptosis 57% (CI: 0.48 to 0.65), diplopia 36% (CI: 0.24 to 0.48) and ocular hypertension 13% (CI: 0.06 to 0.19).

CONCLUSION

A substantial proportion of patients with GD have TED and often manifest as lid retraction, proptosis and diplopia. Early detection through active screening might help to mitigate the progression of TED and its associated complications.

Tear inflammatory cytokines and ocular surface changes in patients with active thyroid eye disease treated with high-dose intravenous glucocorticoids

PURPOSE

To evaluate high-dose intravenous glucocorticoid treatment on tear inflammatory cytokines and ocular surface parameters in patients with active TED. Correlations between tear inflammatory cytokines and clinical parameters were also investigated.

METHODS

This prospective pilot study included 15 moderate-to-severe and active TED patients. Control group consist of 15 sex and age-matched healthy subjects. All TED patients were treated with high-dose intravenous methylprednisolone with cumulative dose of 4.5 g during the therapy subdivided into 12 weekly infusions. Tear concentrations of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-17A, tumor necrosis factor (TNF)-α, and vascular endothelial growth factor (VEGF) were measured by multiplex bead analysis in TED patients at baseline and 12 weeks after treatment. Ocular surface disease index (OSDI), tear break-up time (TBUT), corneal fluorescent staining, and Schirmer's test were obtained from TED and controls.

RESULTS

All baseline cytokine levels except for IL-17A were significantly elevated in active TED patients compared with controls. Concentrations of IL-1β, IL-6, IL-8, TNF-α, and VEGF were significantly decreased at 12 weeks compared with baseline. OSDI and TBUT showed significant improvement at 6 and 12 weeks. There were significant positive correlations between IL-6, IL-8, and CAS, and negative correlation was found between IL-6 level and TED duration before methylprednisolone treatment. The reduction of IL-6, IL-8, and VEGF were positive correlated with the reduction in CAS at 12 weeks.

CONCLUSIONS

High-dose glucocorticoids treatment improved ocular surface symptom, increased the tear film stability, and decreased tear inflammatory cytokines in active TED. The reduction of the inflammatory cytokines is consistent with the improvement of clinical parameters.

In Vivo Confocal Microscopy Morphometric Analysis of Meibomian Glands in Patients With Graves Ophthalmopathy

PURPOSE

To characterize meibomian glands (MGs) features in patients with Graves ophthalmopathy (GO) by in vivo confocal microscopy (IVCM) and to further investigate possible correlations with ocular surface characteristics.

METHODS

Consecutive patients with GO and controls were enrolled. The following ocular surface parameters were measured: tear break-up time, Schirmer test, and corneal fluorescein staining (Oxford score) were performed on each subject. IVCM of MGs was performed, and the scans were analyzed with ImageJ software for the calculation of the following: acinar unit density, total gland area, total lumen area (TLA), acinar longest diameter, and acinar shortest diameter. A nonparametric Mann-Whitney U test was used to compare variables between patients with GO and controls. The Spearman correlation analysis was used to evaluate the correlations between ocular surface and IVCM parameters.

RESULTS

Twenty-one patients with GO and 24 sex- and age-matched healthy controls were included. Acinar unit density was significantly lower in patients with GO compared with controls (24.5 ± 8.1 vs. 34.2 ± 7.5 U/mm; P < 0.001). In addition, patients with GO showed significantly higher values of TLA, acinar longest diameter, and acinar shortest diameter compared with controls (respectively, 3104.7 ± 1713.3 vs. 1393.8 ± 448.0 μm, 94.4 ± 21.2 vs. 64.3 ± 10.1 µm and 56.6 ± 15.3 vs. 42.2 ± 12.3 μm; always P < 0.05). In patients with GO, TLA showed a significant inverse correlation with Schirmer test (Rs = -0.467; P = 0.038).

CONCLUSIONS

IVCM allowed to detect distinctive features of MGs in patients with GO and could represent a surrogate tool for the assessment of MG status in these patients.

On the in vivo assessment of goblet cells of the human bulbar conjunctiva by confocal microscopy - A review

BACKGROUND

In vivo confocal microscopy (IVCM) has been used for over 10 years to assess the goblet cell density (GCD) within the human conjunctiva, but the reported values have been variable with no obvious indications as to why.

METHODS

From publications between 2008 and 2019, representative GCD values were extracted, as well as on the image sampling strategy used.

RESULTS

Average GCD values for any particular group of individuals ranged from 7 to 979 goblet cells / sq. mm, and with one notable outlier removed, an overall group-mean value for GCD (+/- SD) from single site locations was 207 +/- 143 goblet cells / sq. mm from 15 data sets for those usually designated as control subjects, with a value of 190 +/- 161 goblet cells / sq. mm calculated from 20 single site data sets from other (patient) groups. An overall analysis indicated that the reported average values for GCD from different groups of individuals increased according to the number of images assessed / individual (Spearman rho = 0.304), on the number of individuals evaluated to generate an averaged value for each group (rho = 0.367), and the total number of images assessed (rho = 0.346, multivariate analysis partial r = greater or = to 0.522).

CONCLUSIONS

In the use of confocal microscopy to assess the number of goblet cells in the human bulbar conjunctiva, the substantial differences reported appear to be linked to the protocols used for image selection, and some type of standardization needs to be developed.

Local Ocular Surface Alterations in Children with Hashimoto's Thyroiditis

PURPOSE

To evaluate the ocular surface characteristics based on Schirmer's test, tear break-up time (TBUT), and conjunctival impression cytology (CIC) in children with Hashimoto's thyroiditis (HT).

METHODS

This study included 51 children with HT and 53 control subjects. The ocular surface characteristics of participants were assessed via Schirmer's test, TBUT, and CIC. Conjunctival samples were examined cytologically according to the Nelson grading system.

RESULTS

Schirmer's and TBUT results were significantly lower in HT group (p < .05). All samples in both the study and control groups were evaluated as grade 0 according to the Nelson classification (p = .841), however, goblet cell density (GCD) was significantly lower in HT group (p = .001). Schirmer test results were significantly associated with the duration of HT (p = .025, r = -0.311).

CONCLUSION

Hashimoto's thyroiditis without any ocular complaints may cause ocular surface changes with TBUT and Schirmer's. Although CIC analysis showed similar grading results, GCD was significantly decreased in HT group.

Goblet cell density estimate differences in impression cytology samples varies with different magnification of images

PURPOSE

To assess the impact of using different microscope magnifications for the goblet cell density (GCD) estimates from conjunctival impression cytology (CIC) samples from healthy individuals METHODS: In a prospective study, CIC specimens were collected from the superior bulbar conjunctiva (12 o'clock, 5mm from limbus) of 20 adult subjects (average age 22 years) onto Millicell-CM membranes and Giemsa stained. A region from each CIC filter containing reasonably high numbers of goblet cells was imaged by light microscopy at a final magnification of 400X and then the same region assessed at 200X and then 100X. The images were enlarged, the goblet cells marked and counted and GCD values/sq mm calculated.

RESULTS

The mean GCD estimates at 400X magnification, 200X and 100X were 644±180, 405±72 and 365±81 cells/sq mm respectively, and these values were statistically different (p<0.001).

CONCLUSIONS

As a result of non-uniform distribution, a strategy to select a 400X high power microscope field (HPF) that appears to include a moderate number of goblet cells will have a probability (by at least 20:1) that the GCD estimates will likely be higher compared to those at 200X or 100X, and the probability for higher GCD values is at least 15:1 comparing assessments made at 200X to 100X. Investigators should use only one magnification, with that of a medium power field (200X final magnification) likely being the most useful.

Biomarkers of ocular surface disease using impression cytology

Impression cytology (IC) is a technique which permits the retrieval of the outermost layer of ocular surface cells via the use of various types of filters. It is a minimally invasive method of evaluating human conjunctival epithelial cell morphology in the diagnosis of dry eye disease, a common and distressing disorder associated with ageing, contact lens wear, autoimmune disorders and refractive (LASIK) surgery. IC may also be utilized in the diagnosis of other ocular diseases, such as keratoconus and thyroid orbitopathy. More recently, IC has been utilized for the subsequent investigation of gene and protein expression of conjunctival cells in order to identify novel diagnostic biomarkers and to further our understanding of the mechanisms underlying ocular surface disease. This review will therefore examine the literature concerning the role of IC in identifying cellular markers of eye disease, systemic diseases with ocular involvement and potential novel therapeutic targets.

Automatic analysis of corneal nerves imaged using in vivo confocal microscopy

Interest has grown over the past decade in using in vivo confocal microscopy to analyse the morphology of corneal nerves and their changes over time. Advances in computational modelling techniques have been applied to automate the estimation of sub-basal nerve structure. These objective methods have the potential to quantify nerve density (and length), tortuosity, variations in nerve thickness, as well as temporal changes in nerve fibres such as migration patterns. Different approaches to automated nerve analysis, methods proposed and how they were validated in previous literature are reviewed. Improved understanding of these approaches and their limitations will help improve the diagnostic leverage of emerging developments for monitoring the onset and progression of a broad class of systemic diseases, including diabetes.

Comparative proteomic analysis of tear fluid in Graves' disease with and without orbitopathy

BACKGROUND

Graves' orbitopathy (GO) is a severe organ-specific autoimmune inflammatory ocular complication most often associated with Graves' disease (GD). Besides the cosmetic problems these patients develop, GO may also cause severe, sight-threatening complications. Additionally, GO complicates the treatment of patients with GD, making the identification of Graves patients at risk for eye disease before they develop symptoms a critical step in the clinical management and quality of life of these patients. The high concentration of proteins in tear fluid makes it an important source for studying potential protein biomarkers for GO.

PATIENTS AND METHODS

The aim of this study was to quantitatively compare tear fluid from GD patients with moderate/severe GO (GO) and patients with GD without GO (controls) using untargeted quantitative proteomics based on dimethyl labelling in combination with two-dimensional liquid chromatography-mass spectrometry.

RESULTS

Among the 1212 proteins identified, 16 showed significant alterations in abundance between the two groups. Thus, in this study, we reveal a number of novel dysregulated proteins in GO which may contribute to a better understanding of the disease. In particular, upregulation of lacrimal gland proteins such as lysozyme C, lacritin, antileukoproteinase and zinc-alpha-2-glycoprotein 1 suggests involvement of the lacrimal gland in the pathogenesis of GO.

CONCLUSIONS

It remains to be elucidated whether some of these proteins can be used as markers for patients at risk for developing GO as well as useful indicators for disease activity.

Observation of Corneal Langerhans Cells by In Vivo Confocal Microscopy in Thyroid-Associated Ophthalmopathy

PURPOSE

To examine the density and morphology of Langerhans cells (LCs) in the cornea of patients with thyroid-associated ophthalmopathy (TAO).

METHODS

Forty patients with TAO and 20 healthy volunteers were studied. All subjects underwent a thorough ophthalmic examination of both eyes. The ocular surface status was assessed by Ocular Surface Disease Index (OSDI) symptom questionnaires, tear break-up time (BUT), fluorescein staining and the Schirmer test. Laser scanning in vivo confocal microscopy was applied to evaluate the LC density and morphology in both central and peripheral cornea. The correlations between confocal microscopy data and clinical data were also analyzed.

RESULTS

The OSDI and fluorescein staining values were significantly higher, while BUT and Schirmer test scores were lower in both active and inactive TAO patients compared to the controls. Central LC densities of patients with active TAO (76.38 ± 67.77 cell/mm(2)) and inactive TAO (47.49 ± 38.58 cell/mm(2)) were both significantly higher than those of the controls (21.46 ± 21.74 cell/mm(2)). The number of LCs in the peripheral cornea was also significantly increased in the active TAO group (131.53 ± 74.18 cell/mm(2)) compared to the control group (70.21 ± 37.76 cell/mm(2)). Central LC morphology (LCM) values were significantly higher in both active (1.77 ± 0.63) and inactive (1.51 ± 0.63) TAO groups compared to the control group (1.01 ± 0.80), whereas peripheral LCM scores of the two TAO groups were increased without statistical significance. There were significant correlations between both central LC density and central LCM scores and clinical data, including clinical activity score, OSDI and Schirmer test scores, and between peripheral LC density and OSDI and Schirmer test scores. No significant correlations were found between peripheral LCM scores and clinical data.

CONCLUSIONS

The increase of corneal LCs in density and maturation in patients with TAO reflects an activated state of the local immune system, which indicates an inflammatory process in the cornea of TAO.

Changes of Ocular Surface and the Inflammatory Response in a Rabbit Model of Short-Term Exposure Keratopathy

Purpose

To evaluate the ocular surface change and the inflammatory response in a rabbit model of short-term exposure keratopathy.

Methods

Short term exposure keratopathy by continuous eyelid opening was induced in New Zealand white rabbits for up to 4 hours. Ultrasound pachymetry was used to detect central total corneal thickness. In vivo confocal microscopy and impression cytology were performed to evaluate the morphology of ocular surface epithelium and the infiltration of inflammatory cells. Immunohistochemistry for macrophage,neutrophil, CD4(+) T cells, and CD8(+) T cells were performed to classify the inflammatory cells. Scanning electron microscopy(SEM) was performed to detect ocular surface change.The concentrations of IL-8, IL-17, Line and TNF-αwere analyzed by multiplex immunobead assay. TUNEL staining was performed to detect cellular apoptosis.

Results

Significant decrease ofcentral total cornealthickness were found within the first 5 minutes and remained stable thereafter, while there were no changes of corneal epithelial thickness.No significant change of corneal, limbal and conjunctival epithelial morphology was found by in vivo confocal microscopy except the time dependent increase of superficial cellular defects in the central cornea. Impression cytology also demonstrated time dependent increase of sloughing superficial cells of the central cornea. Aggregations ofinflammatory cells were found at 1 hour in the limbal epithelium, 2 hours in the perilimbal conjunctival epithelium, and 3 hours in the peripheral corneal epithelium.In eyes receiving exposure for 4 hours, the infiltration of the inflammatory cells can still be detected at 8 hours after closing eyes.Immunohistochemical study demonstrated the cells to be macrophages, neutrophils, CD4-T cells and CD-8 T cells.SEM demonstrated time-depending increase of intercellular border and sloughing of superficial epithelial cells in corneal surface. Time dependent increase of IL-8, IL-17 and TNF-α in tear was found.TUNEL staining revealed some apoptotic cells in the corneal epithelium and superficial stroma at 3 hours after exposure.

Conclusions

Short term exposure keratopathy can cause significant changes to the ocular surface and inflammatory response. Decrease of central total corneal thickness, aggregation of inflammatory cells, and cornea epithelial cell and superficial keratocyte apoptosis were found no less than 4 hours following the insult.