Subjective versus objective dry eye disease in patients with moderate-severe thyroid eye disease

Ocular surface and meibomian gland evaluation in euthyroid Graves' ophthalmopathy

PURPOSE

Euthyroid Graves' ophthalmology (EGO) refers to the subgroup of thyroid eye disease patients with distinct clinical presentations. This study evaluated the ocular surface and meibomian gland changes in EGO patients.

METHODS

A cross-sectional study was conducted at The Chinese University of Hong Kong including 34 EGO patients and 34 age-and sex- matched healthy controls. Outcome measures include anterior segment examination, keratographic and meibographic imaging.

RESULTS

Between 34 EGO patients and 34 age and sex-matched healthy controls, EGO was associated with a higher ocular surface disease index (P < 0.01), higher severity of meibomian gland dropout (upper: P < 0.001, lower: P < 0.00001) and higher percentage of partial blinking (P = 0.0036). The worse affected eyes of the EGO patients were associated with corneal staining (P = 0.0019), eyelid telangiectasia (P = 0.0009), eyelid thickening (P = 0.0013), eyelid irregularity (P = 0.0054), meibomian gland plugging (P < 0.00001), expressibility (P < 0.00001), and meibum quality (P < 0.00001). When the two eyes of the same EGO patient were compared, the degree of meibomian gland dropout was higher among the worse affected eyes (upper: P < 0.00001, and lower: P < 0.00001). Tear meniscus height, lipid layer thickness, and noninvasive break-up time were comparable between the two eyes of EGO patients and also between EGO patients and healthy controls. TMH was positively correlated with the degree of exophthalmos (r = 0.383, P < 0.05).

CONCLUSION

EGO patients have more ocular surface complications and meibomian gland dropouts than healthy controls. Almost 60% of them had dry eye symptoms, but aqueous deficiency was not apparent. Further studies are warranted to clarify the mechanism of dry eye in EGO. (249 words).

Dysthyroid Optic Neuropathy

PURPOSE

Dysthyroid optic neuropathy (DON) is a sight-threatening complication of thyroid eye disease (TED). This review provides an overview of the epidemiology, pathogenesis, diagnosis, and current therapeutic options for DON.

METHODS

A literature review.

RESULTS

DON occurs in about 5% to 8% of TED patients. Compression of the optic nerve at the apex is the most widely accepted pathogenic mechanism. Excessive stretching of the nerve might play a role in a minority of cases. Increasing age, male gender, smoking, and diabetes mellitus have been identified as risk factors. Diagnosis of DON is based on a combination of ≥2 clinical findings, including decreased visual acuity, decreased color vision, relative afferent pupillary defect, visual field defects, or optic disc edema. Orbital imaging supports the diagnosis by confirming apical crowding or optic nerve stretching. DON should be promptly treated with high-dose intravenous glucocorticoids. Decompression surgery should be performed, but the response is incomplete. Radiotherapy might play a role in the prevention of DON development and may delay or avoid the need for surgery. The advent of new biologic-targeted agents provides an exciting new array of therapeutic options, though more research is needed to clarify the role of these medications in the management of DON.

CONCLUSIONS

Even with appropriate management, DON can result in irreversible loss of visual function. Prompt diagnosis and management are pivotal and require a multidisciplinary approach. Methylprednisolone infusions still represent first-line therapy, and surgical decompression is performed in cases of treatment failure. Biologics may play a role in the future.

Ocular Surface Disease Related to the Inflammatory and Non-Inflammatory Phases of Thyroid Eye Disease

Purpose

This study evaluated the ocular surface disease (OSD), especially dry eye disease (DED) parameters by combining qualitative and quantitative tools, including tear matrix metalloproteinase 9 (MMP-9), in patients with Graves' disease (GD) with and without Thyroid eye disease (TED).

Patients and Methods

A total of 17 active TED, 16 inactive TED, 16 GD without ophthalmopathy, and 16 healthy controls were included. All patients were assessed with CAS, ophthalmometry, qualitative tear MMP-9, Ocular Surface Disease Index (OSDI), ocular surface staining, Schirmer test, meibography, tear meniscus height, conjunctival hyperemia, and non-invasive tear film break-up time. Patients were classified into three subtypes of DED: aqueous tear deficiency, meibomian gland dysfunction (MGD) and mixed dry eye.

Results

Inactive TED was shown to be an associated factor with DED (odds ratio 14, confidence interval 2.24-87.24, p=0.0047), and presented more DED than healthy controls (87.5% versus 33.3%, p=0.0113). MGD was also more prevalent among these subjects than in healthy control (62.5% versus 6.7%; p=0.0273). No significant differences were found in other ophthalmological parameters, except for more intense conjunctival redness among active TED than GD without ophthalmopathy (p=0.0214). Qualitative MMP-9 test was more frequently positive in both eyes among active TED than in other groups (p < 0.0001).

Conclusion

Patients with GD were symptomatic and presented a high prevalence of ocular surface changes and DED, particularly the subgroup with inactive TED. Tear MMP-9 detection was associated with active TED suggesting a relationship between ocular surface changes and the initial inflammatory phase of ophthalmopathy.

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.

A clinical decision support system for diagnosing and determining severity of dry eye disease

INTRODUCTION

Dry eye and its related symptoms are the most common causes of referrals to the ophthalmology centers. Since people with dry eye may suffer from different levels of the disease severity, this study aimed to develop a clinical decision support system for diagnosing and determining severity of dry eye disease.

METHODS

This research was carried out in two phases in 2020. In the first phase, a questionnaire was designed to identify the most important diagnostic parameters from the cornea specialists' perspectives (n = 37). In the second phase of the research, a clinical decision support system was designed and implemented by using MATLAB software. Finally, the system was evaluated using patient data which were collected in a teaching hospital (n = 50).

RESULTS

The diagnostic parameters for dry eye disease were filamentary keratitis, meibomian gland dysfunction, score of ocular surface disease index, Schirmer's test result, tear meniscus height, tear breakup time, and fluorescein staining score. The system output variables were the diagnosis and severity of dry eye disease at four levels for the right and left eyes, separately. The results of the evaluation study showed that the accuracy, sensitivity and specificity of the system were 96.9%, 97.5%, and 93.7%, respectively.

CONCLUSION

It seems that the system designed in this study can help ophthalmologists to diagnose dry eye disease more accurately and quickly. However, it is recommended to conduct more evaluation studies and include more patients in the future research.

3% diquafosol sodium eye drops in Chinese patients with dry eye: a phase IV study

Introduction

The efficacy and safety of 3% diquafosol sodium eye drops in Chinese patients with dry eye in the real-world setting remains unclear.

Methods

3099 patients with dry eye symptoms were screened according to Asia Dry Eye Society latest recommendation. Among them, 3000 patients were enrolled for a phase IV study. We followed up with multiple clinical characteristics including corneal fluorescein staining, tear break up time, Schirmer's tests, visual acuity, intraocular pressure, and others. The follow ups were performed at baseline, 2 weeks and 4 weeks after treatment.

Results

Based on the results of corneal fluorescein staining and tear break up time, all age and gender subgroups exhibited obvious alleviation of the symptoms among the patients with dry eye, and the data in elderly group showed the most significant alleviation. All the adverse drug reactions (ADRs, 6.17%) were recorded, among which 6% local ocular ADRs were included. Meanwhile, mild ADRs (91.8%) accounted for the most. Most of the ADRs (89.75%) got a quick and full recovery, with an average time at 15.6 days. 1.37% of patients dropped out of the study due to ADRs.

Discussion

The use of 3% diquafosol sodium eye drop is effective and safe in the treatment of dry eye, with a low incidence of ADRs showing mild symptoms. This trial was registered at Chinese Clinical Trial Registry ID: ChiCTR1900021999 (Registration Date: 19/03/2019).

Analysis of diagnostic tests in patients with dry eye and hypothyroidism: an observational study

PURPOSE

Colombia is a country with a high prevalence of hypothyroidism, approximately 18.5% compared to the rest of Latin American countries, which is estimated at 10%. That is why in the ophthalmology consultation we find a large proportion of patients with this disease and who also present symptoms of dry eye. When conducting a search in the medical literature, most publications refer to the clinical presentation of dry eye in hyperthyroidism, which is why the main objective of this study is to evaluate tear function tests in the diagnosis of dry eye in patients with hypothyroidism.

METHODS

This is an observational, cross-sectional study carried out in the period between May and December 2019 in the ocular surface unit of the Ophthalmic Technology Center (CTO) in Bogotá. The tests of: OSDI test (Ocular Surface Disease Index), Schirmer type I, tear meniscus height, NiBUT, Osmolarity, Ferning test, Lisamine Green test of 59 patients with Dry Eye Disease (DED) and history of hypothyroidism.

RESULTS

Schirmer type I and NiBUT tests were the parameters that presented the highest percentage of severity, while lissamine green staining and meniscometry showed a tendency to normality.

CONCLUSIONS

The population of this study presents a mixed type dry eye without epithelial cell damage.

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.

Rear 4-min Schirmer test, a modified indicator of Schirmer test in diagnosing dry eye

This study aims to investigate the reliability and efficacy of rear 4-min Schirmer test, as a supplement indicator, in assessing tear secretion and diagnosing dry eye. 180 participants were enrolled in this study. Schirmer test I without anaesthesia was performed once on both eyes to determine the value of normal Schirmer test. The values of tear secretion were recorded at each minute. Other examinations included the following: the ocular surface disease index (OSDI), the standard patient evaluation of eye dryness (SPEED), fluorescein stain, tear film break-up time (BUT), and Meibomian gland (MG) secretion grading. The participants were divided into dry eye (DE) group and non-dry eye (ND) group. The values of the 2-min Schirmer test, rear 3-min Schirmer test, rear 4-min Schirmer test, and 5-min Schirmer test were 5.36 ± 4.63, 5.57 ± 2.11, 7.21 ± 4.13, and 10.93 ± 6.30, respectively, in the DE group. These indicators were 8.25 ± 6.80, 2.73 ± 2.31, 7.36 ± 3.42, and 11.84 ± 6.16, respectively, in the ND group. The rear 4-min Schirmer test had a significant correlation with OSDI and SPEED in the DE group (r =  − 0.242/ − 0.183) and in the ND group (r =  − 0.316/ − 0.373). Meanwhile, the rear 4-min Schirmer test had a stronger connection with fBUT (r = 0.159) and MG secretion (r =  − 0.162) in the DE group and also had higher accuracy in diagnosing severe DE and borderline DE. In conclusion, the rear 4-min Schirmer test may be a supplement indicator in assessing tear secretion and diagnosing DE.

Dry eye disease, a prominent manifestation of systemic autoimmune disorders

OBJECTIVES

Dry eye disease (DED) is arguably the most frequent ocular disease encountered in ophthalmic clinical practice. DED is frequently an underestimated condition causing a significant impact on visual function and quality of life. Many systemic autoimmune diseases (SAIDs) are related to moderate to severe DED. The main objective of this review is to enhance the awareness among ophthalmologists of the potential association of an underlying SAID in a high-risk patient with DED.

METHODS

An exhaustive literature search was performed in the National Library of Medicine's Pubmed, Scopus, Web of Science, and Google Scholar databases for all English language articles published until November 2021. The main keywords included "dry eye disease" associated with autoimmune, connective tissue, endocrine, gastrointestinal, hematopoietic, vascular, and pulmonary diseases. Case reports, series, letters to the editor, reviews, and original articles were included.

RESULTS

Although DED is frequently associated with SAIDs, its diagnosis is commonly delayed or missed, producing significant complications, including corneal ulceration, melting, scleritis, uveitis, and optic neuritis resulting in severe complications detrimental to visual function and quality of life. SAID should be suspected in a woman, 30 to 60 years old with a family history of autoimmunity, presenting with DED symptoms and extraocular manifestations including arthralgias, dry mouth, unexplained weight and hair loss, chronic fatigue, heat or cold intolerance, insomnia, and mood disorders.

CONCLUSIONS

Establishing the correct diagnosis and treatment of DED associated with SAIDs is crucial to avoid its significant burden and severe ocular complications.

Diffusion Tensor Imaging Technology to Quantitatively Assess Abnormal Changes in Patients With Thyroid-Associated Ophthalmopathy

Objective

We aim to investigate the feasibility of using diffusion tensor imaging (DTI) to evaluate changes in extraocular muscles (EOMs) and lacrimal gland (LG) in patients with thyroid-associated ophthalmopathy (TAO) and to evaluate disease severity.

Materials and Methods

A total of 74 participants, including 17 healthy controls (HCs), 22 patients with mild TAO, and 35 patients with moderate-severe TAO, underwent 3-Tesla DTI to measure fractional anisotropy (FA) and mean diffusivity (MD) of the EOMs and LG. Ophthalmological examinations, including visual acuity, exophthalmos, intraocular pressure, and fundoscopy, were performed. FA and MD values were compared among patients with different disease severity. Multiple linear regression was adopted to predict the impact of clinical variables on DTI parameters of orbital soft tissue.

Results

TAO patients’ EOMs and LG showed significantly lower FA values and higher MD compared to HCs’ (P < 0.05). Moderate-severe TAO patients’ EOMs and LG had dramatically lower FA and higher MD compared with HCs (P < 0.05). In addition, only the DTI parameters of the medial rectus were considerably different between mild and moderate-severe TAO patients (P = 0.017, P = 0.021). Multiple linear regression showed that disease severity had a significant impact on the DTI parameters of orbital soft tissue.

Conclusion

DTI is a useful tool for detecting microstructural changes in TAO patients’ orbital soft tissue. DTI findings, especially medial rectus DTI parameters, can help to indicate the disease severity in TAO patients.

Ocular surface disease in thyroid eye disease: A narrative review

Ocular surface disease (OSD) in the setting of thyroid eye disease (TED) is traditionally thought of as a natural consequence of anatomical changes such as proptosis and corneal exposure. However, a growing body of research suggests that ocular surface inflammation and multi-factorial changes to the homeostasis of the ocular surface contribute substantially to the OSD seen in TED patients. In this paper we review the existing literature which highlights the work and existing theories underlying this new paradigm shift.

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.

Systemic Conditions Associated with Severity of Dry Eye Signs and Symptoms in the Dry Eye Assessment and Management Study

PURPOSE

Certain systemic conditions are reported to be risk factors for dry eye disease (DED), but their associations with DED severity are not well studied. We evaluated whether systemic conditions reported to be DED risk factors are associated with severity of DED signs and symptoms.

DESIGN

Secondary analysis of data from the Dry Eye Assessment and Management Study, a large-scale multicenter randomized clinical trial of patients with moderate to severe DED.

PARTICIPANTS

Five hundred thirty-five adult patients with moderate to severe DED from 27 United States centers.

METHODS

Patients reported their medical history at baseline. They underwent ocular surface examinations and symptom evaluation using standardized protocols at baseline, 6 months, and 12 months. We analyzed the associations of systemic conditions (a systemic disease or smoking history) reported as potential DED risk factors with the severity of DED signs and symptoms using generalized linear regression models adjusted by age, gender, race, and visit.

MAIN OUTCOME MEASURES

Dry eye disease symptoms assessed using the Ocular Surface Disease Index (OSDI), 6 DED signs (tear film break-up time, anesthetized Schirmer testing, corneal fluorescein staining, conjunctival lissamine green staining, tear osmolarity, and meibomian gland dysfunction), and a composite signs severity score from 0 to 1 (1 = most severe).

RESULTS

The mean age was 58 years; 81% were women. More severe DED signs were associated significantly with Sjögren syndrome (mean composite signs severity score 0.52 with disease vs. 0.43 without disease; P < 0.001), facial rosacea (0.47 vs. 0.43; P = 0.002), rheumatoid arthritis (0.47 vs. 0.42; P = 0.002), peripheral artery disease (0.50 vs. 0.43; P < 0.001), and daily smoking history (0.45 vs. 0.43; P = 0.047). Thyroid dysfunction, osteoarthritis, diabetes, irritable bowel syndrome, hypercholesterolemia, hypertension, and hypertriglyceridemia were not associated significantly with DED signs. No conditions were associated significantly with OSDI.

CONCLUSIONS

In this large, well-characterized cohort of patients with DED assessed under standardized procedures, patients with certain systemic diseases and smoking history showed more severe DED signs compared with patients without the conditions. The profile of significant DED signs varied by systemic condition, reflecting different DED causes. Understanding the systemic conditions and underlying causes that predispose some patients to severe DED can improve management.

Systemic diseases and the cornea

There is a number of systemic diseases affecting the cornea. These include endocrine disorders (diabetes, Graves' disease, Addison's disease, hyperparathyroidism), infections with viruses (SARS-CoV-2, herpes simplex, varicella zoster, HTLV-1, Epstein-Barr virus) and bacteria (tuberculosis, syphilis and Pseudomonas aeruginosa), autoimmune and inflammatory diseases (rheumatoid arthritis, Sjögren's syndrome, lupus erythematosus, gout, atopic and vernal keratoconjunctivitis, multiple sclerosis, granulomatosis with polyangiitis, sarcoidosis, Cogan's syndrome, immunobullous diseases), corneal deposit disorders (Wilson's disease, cystinosis, Fabry disease, Meretoja's syndrome, mucopolysaccharidosis, hyperlipoproteinemia), and genetic disorders (aniridia, Ehlers-Danlos syndromes, Marfan syndrome). Corneal manifestations often provide an insight to underlying systemic diseases and can act as the first indicator of an undiagnosed systemic condition. Routine eye exams can bring attention to potentially life-threatening illnesses. In this review, we provide a fairly detailed overview of the pathologic changes in the cornea described in various systemic diseases and also discuss underlying molecular mechanisms, as well as current and emerging treatments.

Changes in ocular biomechanics after treatment for active Graves' orbitopathy

PURPOSE

To evaluate the changes in ocular biomechanical properties in active moderate-to-severe Graves' orbitopathy (GO) after intravenous glucocorticoids (IVGCs), and to clarify correlations between clinical findings and ocular biomechanical properties.

METHODS

A prospective study. A total of 20 consecutive GO patients and 20 age- and sex-matched healthy control subjects were included. GO was diagnosed on the basis of the recommendation by the European Group on Graves' Orbitopathy (EUGOGO), and disease activity was assessed by the clinical activity score (CAS). Patients were assigned to receive once weekly IVGCs (0.5 g, then 0.25 g, 6 weeks each). All participants received a full ophthalmic examination and biomechanical evaluation was performed with dynamic Scheimpflug analyzer (Corvis ST) at baseline and 12th weeks after therapy.

RESULTS

The biomechanically corrected intraocular pressure (bIOP) in GO patients was significantly higher than that in healthy subjects. In contrast, the whole eye movement (WEM) in GO patients was significantly lower than in healthy subjects after adjusting for bIOP. The CAS, NOSPECS score, and exophthalmos were significantly positively correlated with the bIOP and negatively correlated with the WEM after adjusting for bIOP, CCT and age. The WEM significantly increased, whereas bIOP significantly decreased after IVGCs (P < 0.001, P = 0.001 respectively). The overall response rate at the 12th week was 85% (17 of 20).

CONCLUSIONS

The changes of ocular biomechanical properties measured by Corvis ST were an objective indicator of inflammatory activity and severity of GO. Combining CAS and ocular biomechanical properties could better evaluate the therapeutic outcome of active moderate-to-severe GO.

Ocular Surface Changes in Hashimoto's Thyroiditis Without Thyroid Ophthalmopathy

OBJECTIVE

We sought to evaluate ocular surface changes in patients with Hashimoto's thyroiditis without thyroid ophthalmopathy and elucidate the relationship between dry eye syndrome and meibomian gland dysfunction (MGD) in cases of Hashimoto's thyroiditis.

METHODS

This prospective study included 105 patients with Hashimoto's thyroiditis and 105 age- and sex-matched controls. The 12-item Ocular Surface Disease Index (OSDI) questionnaire was administered to all patients. Both eyes affected by Hashimoto's thyroiditis and normal eyes were evaluated and compared with regard to the following parameters: Hertel exophthalmometry, palpebral fissure height, tear-film breakup time (TBUT), Schirmer 1 test, area and density scores for corneal fluorescein staining, eyelid abnormality, meibomian gland expression, meibography scores, and areas of meibomian gland loss.

RESULTS

The eyes affected by Hashimoto's thyroiditis demonstrated significantly lower TBUTs (P<0.001), Schirmer 1 test scores (P<0.001), and meibomian gland expression (P<0.05) and significantly higher OSDI scores (P<0.001), corneal fluorescein staining results (P<0.05), eyelid abnormality scores (P<0.05), meibography scores (P<0.05), and areas of meibomian gland loss (P<0.05). Ocular Surface Disease Index scores were significantly positively correlated with eyelid abnormality scores (P=0.025), meibography scores (P<0.05), and areas of meibomian gland loss (P<0.05) and negatively correlated with meibomian gland expression (P<0.05). The duration of Hashimoto's thyroiditis was significantly positively correlated with MGD (P<0.05).

CONCLUSION

Dry eye syndrome and ocular discomfort symptoms are significantly more common among patients with Hashimoto's thyroiditis, even in the absence of thyroid ophthalmopathy. Dry eye syndrome in patients with Hashimoto's thyroiditis is believed to result from MGD and is correlated with the duration of the thyroid disease.

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.