Changes of meibomian glands in patients with type 2 diabetes mellitus

Association of peripheral neuropathy with dry eye disease and meibomian gland dysfunction in patients with type 1 diabetes

PURPOSE

To explore the relationship between dry eye disease and type 1 diabetes mellitus (DM) and also to identify whether diabetic peripheral neuropathy (DPN) was a significant predictor for the development of dry eye disease.

MATERIALS AND METHODS

This prospective cross sectional study involved patients with type 1 DM and aged- and sex-matched healthy controls. All of the participants underwent dry eye tests including meibomian gland function. Based on neurologic examination and electromyography findings, diabetic patients were grouped as DPN + and DPN-. All findings were compared and predictive factors for dry eye disease were identified.

RESULTS

Of the 97 patients with type 1 DM, 42 (43.3%) were diagnosed as DPN. In patients with DM, there was a significant increase in the ocular surface disease index, corneal surface staining, eyelid margin abnormality and meibomian gland dysfunction and a significant decrease in tear break-up time and Schirmer's I test (p < 0.05). Measurements of dry eye tests were more severe with the presence of DPN (p < 0.05). Age of the patients, duration of DM and HbA1c level were significantly correlated with ocular surface and meibomian gland dysfunction parameters (p < 0.05). Age of the patients (p < 0.001), duration of DM (p = 0.001), HbA1c level (p = 0.036) and presence of DPN (p < 0.001) were found to be the independent and significant predictors of dry eye disease.

CONCLUSION

Type 1 DM was found to be significantly associated with ocular surface abnormalities including meibomian gland dysfunction. Furthermore, age of the patients, duration of DM, HbA1c level and presence of DPN were predictive factors of dry eye disease in type 1 DM.

Improvement in signs and symptoms of severe dry eye disease after dual therapy with high-potency steroids and 0.05% cyclosporine

OBJECTIVE

To evaluate the effectiveness and safety of combining 0.05% cyclosporine A (CsA) with high-potency steroids for treating severe dry eye disease (DED).

MATERIALS AND METHODS

This retrospective comparative case series included 93 patients treated with 0.05% CsA for severe DED. Among them, we included data from 54 eyes of 27 patients who received high-potency steroids in the study group and from 132 eyes of 66 patients who did not receive high-potency steroids in the control group. Data on demographic characteristics, comorbidities, medications and intraocular pressure (IOP) were recorded. The primary outcomes were changes in symptom and sign scores. The ocular surface disease index was used as the symptom score, whereas tear break-up time, Schirmer I test without anaesthesia, ocular surface staining scores and presence of meibomian gland dysfunction were considered as sign scores. Repeated one-way ANOVA and generalized linear mixed models were used to evaluate differences.

RESULTS

In the control group, symptom scores decreased from 1 to 2 months and from 2 to 3 months after treatment (p = .002 and .049). In the high-potency steroid group, symptom scores improved during these intervals (p = .003 and .005). The sign score in the control group remained unchanged (all p > .05), while the high-potency steroid group exhibited progressive improvement in sign scores (all p < .05). The high-potency steroid group had more favourable symptom (p = .035) and sign (p < .001) scores than did the control group. However, multiple systemic diseases were associated with poor symptom (p = .025) and sign (p = .014) scores. The risks for glaucoma and cataract formation were similar between the two groups (all p > .05).

CONCLUSIONS

Dual therapy combining high-potency steroids and 0.05% CsA significantly improved the signs and symptoms of severe DED compared with 0.05% CsA monotherapy, without severe complications.

Inflammation mechanism and anti-inflammatory therapy of dry eye

Dry eye is a widespread chronic inflammatory disease that causes fatigue, tingling, burning, and other symptoms. Dry eye is attributed to rheumatic diseases, diabetes, hormone disorders, and contact lenses, which activate inflammatory pathways: mitogen-activated protein kinases (MAPK) and nuclear factor-B (NF-κB), promote macrophage inflammatory cell and T cell activation, and inflammation factors. Clinicians use a combination of anti-inflammatory drugs to manage different symptoms of dry eye; some of these anti-inflammatory drugs are being developed. This review introduces the dry eye inflammation mechanisms and the involved inflammatory factors. We also elucidate the anti-inflammatory drug mechanism and the detection limits.

Non-contact meibography changes according to disease activity in rheumatoid arthritis cases

PURPOSE

To measure dry eye disease (DED) activity in rheumatoid arthritis (RA) patients, correlate it with the activity and duration of RA, and objectively measure the degree extent of DED in RA active cases.

METHODS

The paper studied the meibomian gland of 30 RA cases referred by the Rheumatology Department, Sohag University Hospitals to Sohag Cornea and Refractive Center, Sohag, Egypt, by infrared non-contact meibography in the Scheimpflug topographer (Sirius, CSO, Italy) from July 2021 to July 2022. The cases fulfilled the RA classification criteria according to the 2010 American College of Rheumatology and European League and underwent full lab investigations. They were distributed to two groups based on the DAS-28 questionnaire. The patients were distributed into low to moderate activity (3.2 < score <  = 5.1) and high activity groups (score > 5.1).

RESULTS

This study included 60 eyes of 30 RA patients. They scored a mean age of (44 ± 10 years), number of swollen joints (3 ± 3), number of tender joints (5 ± 3), duration of disease (8 ± 4), activity of the disease measured by DAS-28 (4.4 ± 0.9), and sex (males were 9.7% vs females 90.3%). The number of swollen joints, tender joints, ESR and DAS-28 were more in the high activity group with the p-value of (0.018, 0.001, < 0.003 and < 0.004), respectively. There are no statistically significant differences between both groups as regards disease duration (p-value of 3.8). The high activity group showed significant affection regarding the mebioscore of the lower and upper lids, total mebioscore, percentage of meibomian glands in upper and lower lids, first non-invasive break-up time test (NIV-BUT) of the tear film, as well as average non-invasive break-up time test (NIavg-BUT). There were moderate correlations between the activity of the disease represented by (DAS-28) and different parameters evaluating eye dryness (meiboscore of the lower and upper lids, total meiboscore, percentage of meibomian glands in upper and lower lids, NIV-BUT of the tear film, and NIavg-BUT of the tear film).

CONCLUSION

There was no correlation with duration of RA but moderate correlations between the activity of the disease represented by (DAS-28) and different parameters evaluating eye dryness in RA patients with valuable use of noncontact Meibography to evaluate eye dryness in RA cases. Both Meiboscore and Meiboscale of Non-contact Meibography were found to be useful tools in grading of dry eye disease in different activity grades of Rheumatoid Arthritis.

Evaluation of central corneal epithelial thickness with anterior segment OCT in patients with type 2 diabetes mellitus

BACKGROUND

This study aimed to evaluate the central corneal thickness (CCT) and central corneal epithelial thickness (CCET) in patients with Type 2 diabetes mellitus (DM), and the effect of the duration of diabetes, the degree of diabetic retinopathy (DR), and HbA1c level.

METHODS

CCT and CCET values of 72 patients diagnosed with type 2 DM and 72 healthy individuals were measured by anterior segment optical coherence tomography. The eye tear function was evaluated with the Tear Break-up Time test (TBUT) and the Schirmer test. From the results of fundus examination, the diabetic patients were grouped as those without DR, non-proliferative DR, and proliferative DR. The disease duration and the HbA1c levels were recorded.

RESULTS

In the diabetic patients, the mean CCT was determined to be thicker (p = 0.025), the CCET was thinner (p = 0.003), and the TBUT and Schirmer values were lower (p <0.001, p <0.001, respectively). The duration of diabetes and the HbA1c level was not found to have any statistically significant effect on these parameters (p >0.05). The presence of retinopathy had no significant effect on CCT, TBUT, and Schirmer values. The CCET was determined to be thinner in patients with retinopathy (p <0.001).

CONCLUSIONS

As the corneal epithelial thickness is reduced in patients with advanced diabetic retinopathy, corneal epithelial pathologies can be seen more often. Therefore, early and effective treatment can be started by taking into consideration the complications which may develop associated with the corneal epithelium following surgical procedures, especially those applied to the cornea.

Tear film layers and meibomian gland assessment in patients with type 1 diabetes mellitus using a noninvasive ocular surface analyzer: a cross-sectional case–control study

Purpose

To assess the tear film layers and Meibomian glands by a noninvasive ocular surface analyzer in patients with and without type 1 diabetes mellitus (T1DM).

Methods

Eighty-eight participants were enrolled in this study: 44 patients with T1DM without diabetic retinopathy, and 44 patients as a control group, between 18 and 49 years old. Limbal and bulbar redness classification, lipid layer thickness (LLT), tear meniscus height (TMH), first and mean noninvasive tear break-up time (FNIBUT and MNIBUT, respectively), and Meibomian glands loss (MGL) were assessment through the ICP Ocular Surface Analyzer (OSA). Schirmer’s I test (SIT), the fluorescein tear break-up time test (TFBUT), OSDI and SPEED questionnaires, and percentage of glycosylated hemoglobin (HbA1c) were also tested.

Results

The T1DM group showed higher limbal and bulbar redness (p = 0.010) and lower LLT (p < 0.001), TMH (p < 0.001), FNIBUT (p < 0.001), MNIBUT (p < 0.001), SIT (p = 0.001), and TFBUT (p < 0.001) than the control group. A higher percentage of MGL was found in the T1DM group in the upper (p = 0.097) and lower (p < 0.001) eyelids. No significant differences were found in dry eye symptoms across the OSDI and SPEED questionnaires between the two groups.

Conclusion

Patients with T1DM without signs of retinopathy showed involvement of the mucoaqueous and lipid layers of the tear film, as well as a higher percentage of MGL, using a noninvasive analyzer. Dry eye disease in people with T1DM cannot be ruled out by anamnesis and subjective symptom questionnaires alone; therefore, these patients should undergo regular anterior pole examinations.

Meibomian gland morphological changes in ocular herpes zoster patients based on AI analysis

Varicella-zoster virus (VZV) infections result in a series of ophthalmic complications. Clinically, we also discover that the proportion of dry eye symptoms was significantly higher in patients with herpes zoster ophthalmicus (HZO) than in healthy individuals. Meibomian gland dysfunction (MGD) is one of the main reasons for dry eye. Therefore, we hypothesize that HZO may associate with MGD, affecting the morphology of meibomian gland (MG) because of immune response and inflammation. The purpose of this study is to retrospectively analyze the effect of HZO with craniofacial herpes zoster on dry eye and MG morphology based on an Artificial intelligence (AI) MG morphology analytic system. In this study, 26 patients were diagnosed as HZO based on a history of craniofacial herpes zoster accompanied by abnormal ocular signs. We found that the average height of all MGs of the upper eyelid and both eyelids were significantly lower in the research group than in the normal control group (p &lt; 0.05 for all). The average width and tortuosity of all MGs for both upper and lower eyelids were not significantly different between the two groups. The MG density of the upper eyelid and both eyelids were significantly lower in the HZO group than in the normal control group (p = 0.020 and p = 0.022). Therefore, HZO may lead to dry eye, coupled with the morphological changes of MGs, mainly including a reduction in MG density and height. Moreover, it is important to control HZO early and timely, which could prevent potential long-term severe ocular surface injury.

Dry eye disease and tear film assessment through a novel non-invasive ocular surface analyzer: The OSA protocol

We describe the role of OSA as a new instrument in the study of dry eye, and we recommend a protocol for conducting the tests as well as describe the advantages and disadvantages compared with other instruments. A comparison with other ocular surface devices (Tearscope Plus, Keratograph 5M, anterior-segment ocular coherence tomography, Easy Tear View-Plus, LipiView, IDRA, and LacryDiag) were presented due to manual or automatic procedure and objective or subjective measurements. The purpose of this study was to describe the OSA as new non-invasive dry eye disease diagnostic device. The OSA is a device that can provide accurate, non-invasive and easy-to-use parameters to specifically interpret distinct functions of the tear film. This OSA protocol proposed a lesser to higher non-invasive ocular surface dry eye disease tear film diagnostic methodology. A complete and exhaustive OSA and OSA Plus examination protocol was presented within the subjective questionnaire (Dry Eye Questionnaire 5, DEQ5), limbal and bulbar redness classification (within the Efron grade Scale, interferometry lipid layer thickness (LLT) (according to Guillon pattern), tear meniscus height (manually or automatic), first and mean non-invasive break up time (objective and automatic) and meibomian gland (MG) dysfunction grade and percentage (objective and automatic). The OSA and OSA Plus devices are novel and relevant dry eye disease diagnostic tools; however, the automatization and objectivity of the measurements can be increased in future software or device updates. The new non-invasive devices supposed represent a renewal in the dry eye disease diagnosis and introduce a tendency to replace the classic invasive techniques that supposed less reliability and reproducibility.

Meibomian Glands and Tear Film Findings in Type 2 Diabetic Patients: A Cross-Sectional Study

Background

The characteristics of the meibomian gland and tear film in patients with type 2 diabetes (T2D) with different glycemic control levels and diabetic durations remain largely unexplored. This study aimed to identify the association of dry eye and meibomian gland dysfunction (MGD) in T2D.

Materials and Methods

Ninety-nine patients with type 2 diabetes mellitus (DM group), 33 dry eye patients without diabetes mellitus (DE group), and 40 normal subjects (NC group) were recruited for this study. Participants were evaluated with an Ocular Surface Disease Index (OSDI) questionnaire, tear film breakup time (BUT), the Schirmer I test (SIT), corneal fluorescein staining (FL), lipid layer thickness (LLT), and MGD parameters. Glycosylated hemoglobin (HbA_1c) and duration of diabetes were recorded.

Results

The SIT value in the DM group was higher than that of the DE group (p < 0.05). The BUT and LLT were lower, and MGD parameters were higher in the DM group than those of the DE and NC groups (p < 0.05). In the DM group, 47 patients were diagnosed with dry eye (DM + DE group), whereas 40 patients without dry eye were categorized as the DM − DE group. The SIT, BUT, and LLT values in the DM − DE group were higher (p < 0.01), and MGD parameters were lower (p < 0.01) in the DM − DE group than those of the DM + DE group. The MGD parameters were higher in the DM − DE group than those in the NC group (p < 0.05). The HbA_1c levels were correlated with OSDI, BUT, LLT, FL, and MGD parameters (p < 0.001) in the DM group. However, in patients with low HbA_1c, normal SIT value, and low OSDI, the MGD parameters were higher than those in the NC group (p < 0.05). The duration of diabetes positively correlated with MGD parameters (p < 0.001).

Conclusion

Asymptomatic MGD may be an early sign of dry eye and ocular discomfort in T2D. The MGD parameters were associated with the HbA_1c level and diabetic duration.

Hyperglycemia Induces Meibomian Gland Dysfunction

Purpose

Patients diagnosed with diabetes are inclined to have abnormalities on stability of tear film and disorder of meibomian gland (MG). This study aims to explore the pathological change of MG induced by diabetes in a rat model.

Methods

Sprague-Dawley (SD) rats were intraperitoneally injected with streptozotocin (STZ) to establish a diabetic animal model. Lipid accumulation in MG was detected by Oil Red O staining and LipidTox staining. Cell proliferation status was determined by Ki67 and P63 immunostaining, whereas cell apoptosis was confirmed by TUNEL assay. Gene expression of inflammatory cytokines and adhesion molecules IL-1α, IL-1β, ELAM1, ICAM1, and VCAM1 were detected by RT-PCR. Activation of ERK, NF-κB, and AMPK signaling pathways was determined by Western Blot analysis. Oxidative stress-related factors NOX4, 4HNE, Nrf2, HO-1, and SOD2 were detected by immunostaining or Western Blot analysis. Tom20 and Tim23 immunostaining and transmission electron microscopy were performed to evaluate the mitochondria functional and structure change.

Results

Four months after STZ injection, there was acini dropout in MG of diabetic rats. Evident infiltration of inflammatory cells, increased expression of inflammatory factors, and adhesion molecules, as well as activated ERK and NF-κB signaling pathways were identified. Oxidative stress of MG was evident in 4-month diabetic rats. Phospho-AMPK was downregulated in MG of 2-month diabetic rats and more prominent in 4-month rats. After metformin treatment, phospho-AMPK was upregulated and the morphology of MG was well maintained. Moreover, inflammation and oxidative stress of MG were alleviated after metformin intervention.

Conclusions

Long-term diabetes may lead to Meibomian gland dysfunction (MGD). AMPK may be a therapeutic target of MGD induced by diabetes.

Mechanistic investigations of diabetic ocular surface diseases

With the global prevalence of diabetes mellitus over recent decades, more patients suffered from various diabetic complications, including diabetic ocular surface diseases that may seriously affect the quality of life and even vision sight. The major diabetic ocular surface diseases include diabetic keratopathy and dry eye. Diabetic keratopathy is characterized with the delayed corneal epithelial wound healing, reduced corneal nerve density, decreased corneal sensation and feeling of burning or dryness. Diabetic dry eye is manifested as the reduction of tear secretion accompanied with the ocular discomfort. The early clinical symptoms include dry eye and corneal nerve degeneration, suggesting the early diagnosis should be focused on the examination of confocal microscopy and dry eye symptoms. The pathogenesis of diabetic keratopathy involves the accumulation of advanced glycation end-products, impaired neurotrophic innervations and limbal stem cell function, and dysregulated growth factor signaling, and inflammation alterations. Diabetic dry eye may be associated with the abnormal mitochondrial metabolism of lacrimal gland caused by the overactivation of sympathetic nervous system. Considering the important roles of the dense innervations in the homeostatic maintenance of cornea and lacrimal gland, further studies on the neuroepithelial and neuroimmune interactions will reveal the predominant pathogenic mechanisms and develop the targeting intervention strategies of diabetic ocular surface complications.

Tear function in patients with diabetes mellitus: A systematic review and meta-analysis

PURPOSE

To examine tear function in patients with diabetes mellitus (DM).

DESIGN

Systematic review and meta-analysis.

METHOD

We searched Embase and PubMed from database inception to March 16, 2022. We included observational studies that compared tear function between patients with and without DM. Tear function was measured using invasive tear breakup time (ITBUT) and Schirmer's 1 test. Pooled results are presented as standard mean difference (SMD) with 95% confidence interval (CI) based on random-effects models.

RESULTS

We included 59 studies (7,234 eyes) comparing the tear function between patients with and without DM. This meta-analysis indicated that patients with DM had worse tear function than those without DM (ITBUT: SMD: -0.98, 95% CI: -1.27 to -0.69; Schirmer's 1 test: SMD: -0.45, 95% CI: -0.64 to -0.26), and the results remained consistent in patients with different types of DM (e.g., type 1 DM and type 2 DM) and from different ethnic backgrounds (e.g., Asian vs. non-Asian). Patients with DM under poor glycemic control had worse tear function than those of the non-DM group (ITBUT: SMD: -1.26, 95% CI: -1.86 to -0.66; Schirmer's 1 test: SMD: -0.25, 95% CI: -0.48 to -0.02), whereas there were no significant differences in tear function between patients with DM under optimal glycemic control and non-DM groups.

CONCLUSIONS

We found that patients with type 1 or type 2 DM had significantly reduced tear function. The level of tear function could be determined by glycemic control, and therefore, our findings suggest that glycemic control in patients with DM is critical for maintaining tear function.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero, identifier CRD42021250498.

The Association Between Risk Factors for Metabolic Syndrome and Meibomian Gland Disease in a Dry Eye Cohort

Purpose

Risk factors for metabolic syndrome include abdominal obesity, insulin resistance, hypertension, high triglycerides and/or low high-density lipoprotein cholesterol, and hyperglycemia. Risk factors for metabolic syndrome have been associated with dry eye disease; however, their association with meibomian gland disease (MGD), a subtype of dry eye, is unclear. In the present study, we investigated risk factors for metabolic syndrome in a dry eye cohort with and without MGD.

Methods

This retrospective case-control study evaluated electronic medical records at a major urban outpatient medical center to identify patients with a known diagnosis of dry eye disease with and without MGD. Males and females were matched for age, smoking status, race, ethnicity, and body mass index (BMI). Patient demographics, anthropometric measurements, medical history, clinical findings, and serologies were analyzed. A diagnosis of MGD was based on clinical signs noted in the medical record.

Results

MGD was not associated with BMI, smoking, type 2 diabetes mellitus, hypertension or hyperlipidemia in this dry eye cohort. MGD was associated with male sex and increasing age. While increasing age was weakly correlated with decreased low density lipoprotein cholesterol and non-high density lipoprotein cholesterol, serum lipid levels were not associated with MGD.

Conclusion

Importantly, we found that risk factors for metabolic syndrome are not specifically associated with an increase in MGD when compared to non-MGD dry eye subjects. While risk factors for metabolic syndrome are associated with dry eye disease, they likely reflect a chronic systemic state of low-grade inflammation that negatively impacts the function of both lacrimal and meibomian glands.

Alterations of Ocular Surface Parameters in Type 2 Diabetic Patients

OBJECTIVE

The purpose of the study was to evaluate the changes in the ocular surface parameters of type 2 diabetic patients.

METHODS

This study is a cross-sectional observational study. It included 76 eyes of 38 patients with type 2 diabetes and 183 eyes of 92 non-diabetic controls. The diabetic subjects were divided into two groups based on diabetic duration. Ocular surface parameters were assessed for all participants.

RESULTS

The diabetic group had a significantly thinner lipid layer thickness (LLT) (p = 0.008) than non-diabetic controls. LLT in the subgroup with diabetic duration ≥10 years was significantly thinner than that in the subgroup with diabetic duration <10 years (p = 0.006). Multivariate linear regression analysis showed that LLT was associated with the duration of diabetes (β = -1.497, p = 0.009) and Schirmer I test (SIT) score (β = 0.852, p = 0.04) in diabetic. Diabetic duration was significantly negatively associated with LLT (β = -0.062, p = 0.004) and significantly positively associated with ocular surface disease index (OSDI) (β = 0.087, p = 0.039).

CONCLUSION

Diabetic patients exhibit significantly reduced LLT and this trend becomes more pronounced with increased duration of diabetes.

To Find Out the Relationship Between Levels of Glycosylated Hemoglobin with Meibomian Gland Dysfunction in Patients with Type 2 Diabetes

Aim

The aim of this study was to investigate the relationship between levels of glycosylated hemoglobin (HbA1c) with meibomian gland dysfunction (MGD) in patients with type 2 diabetes mellitus (T2DM) and to further explore the related influencing factors.

Methods

Totally, 167 patients with T2DM and 68 non-diabetic subjects were selected. Further, T2DM patients were divided into 2 groups based on 7% HbA1c. Standard patient evaluation of eye dryness (SPEED), lipid layer thickness (LLT), partial blink (PB) ratio, percentage of partial glands (MGP), meibomian gland yielding liquid secretion (MGYLS), meibomian gland yielding secretion score (MGYSS), line of marx (LOM), tear break up time (TBUT), tear meniscus height (TMH) and Schirmer I test (SIT) were applied to evaluate meibomian gland function. Finally, the correlation between HbA1c and various indicators was also analyzed.

Results

Between HbA1c≥7% group and HbA1c<7% group, the differences in LLT (P=0.003), MGP (P<0.001), MGYLS (P=0.014) and TBUT (P=0.015) were all statistically significant. Compared with the non-diabetic group, LLT (P=0.020), MBP (P<0.001), MGYS (P< 0.001), TBUT (P<0.001), SIT (P=0.001), TMH (P=0.017) and LOM (P<0.001) were significantly different in HbA1c≥7% group, while the differences of MBP (P=0.031), MGYSS (P<0.001), SIT (P=0.001) and LOM (P<0.001) in HbA1c≤7% group were statistically significant. Besides, the prevalence of MGD in HbA1c≥7% group was evidently higher than that in non-diabetic group (P=0.002). Correlation analysis showed that HbA1c was significantly associated with the LTT and MGP.

Conclusion

HbA1c≥7% is likely to result in meibomian gland function dysfunctions in T2DM patients, especially related to LLT and MGP.

Correlation of the retinopathy degree with the change of ocular surface and corneal nerve in patients with type 2 diabetes mellitus

AIM

To investigate the change of ocular surface and corneal nerve and their correlation in patients suffering from type 2 diabetes mellitus under different degrees of retinopathy.

METHODS

Totally 129 type 2 diabetes mellitus patients (257 eyes) were included. They were divided into three groups: no diabetic retinopathy (NDR) group (33 cases, 66 eyes), non-proliferative diabetic retinopathy (NPDR) group (32 cases, 64 eyes), and proliferative diabetic retinopathy (PDR) group (34 cases, 67 eyes). Healthy normal individuals were enrolled as controls (30 cases, 60 eyes). Ocular Surface Disease Index (OSDI) questionnaire was completed by all subjects, and dry eye analyzer was applied to examine tear meniscus height (TMH), first tear break-up time (FTBUT), average tear break-up time (ATBUT), tear film lipid layer thickness classification, and meibomian gland loss (MGL) score. Corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), corneal nerve fiber length (CNFL), and corneal nerve fiber tortuosity (CNFT) were examined by in vivo confocal microscopy (IVCM). The differences and correlation among these parameters were analyzed.

RESULTS

Total OSDI score, TMH, FTBUT, ATBUT, tear film lipid layer thickness, MGL score, CNFD, CNBD, CNFL, and CNFT were statistically different among the four groups (P<0.05). In NDR group, CNFL was positively correlated with TMH (r=0.493, both P<0.01) and ATBUT (r=0.437, P<0.05). CNFL in NPDR group was positively correlated with TMH (r=0.642, P<0.01) and ATBUT (r=0.6, P<0.01). CNFL in PDR group was positively correlated with TMH (r=0.364, P<0.05) and ATBUT (r=0.589, P<0.01), with low negative correlation with MGL score (r=-0.331, P<0.05).

CONCLUSION

With the progression of diabetic retinopathy, TMH, BUT, lipid layer thickness, CNFL, CNFD, and CNBD gradually decreased, while total OSDI score, MGL score, and CNFT increased. CNFL is correlated with TMH and ATBUT in diabetic patients.

Analysis of Clinical and Regional Distribution Characteristics of Obstructive Meibomian Gland Dysfunction in China: A Multicenter Study

Purpose: To analyze the clinical and regional distribution characteristics of obstructive meibomian gland dysfunction (OMGD) in China. Methods: A total of 2900 patients (2900 eyes) diagnosed with OMGD were enrolled in this multicenter, cross-sectional, observational study. The Ocular Surface Disease Index (OSDI), tear film breakup time (FBUT), Schirmer test (SI), lipid layer thickness (LLT), OMGD grade, meibomian gland loss score (Meiboscore), meibum expressibility score (MES), meibum quality score (MQS), Lid margin abnormality score(LMS) and other tear film stability markers were evaluated. Results: The prevalence of dry eye in OMGD patients was 89%. There were gender differences among OMGD patients in the 30-39 and 50-59 years age groups (p < .05), and FBUT, Meiboscore, MES and MQS were significantly different among different OMGD grades (p < .05). There were significant differences in the detection indexes of OMGD patients in the six regions (p < .05), except LLT (p = .329). According to the Qinling-Huaihe River in China, OMGD patients were divided into the North Group (Shenyang and Beijing) and South Group (Wuhan, Changsha, Chongqing, and Chengdu). There was a significant difference in the detection indexes, except LLT (p = .600), between the two groups (p < .05). FBUT was significantly correlated with the OSDI (r = -0.131; p < .000). Meiboscore and LLT were significantly correlated with the OMGD grade (r = 0.299 and r = 0.106; p < .001). Age, LMS and MQS were significantly correlated with Meiboscore (r = 0.415, r = 0.256 and r = 0.328; p < .001). Conclusions: The prevalence of dry eye was high among OMGD patients. OMGD patients in different age groups may show different gender distributions. The symptoms of patients showed variation among subgroups with different OMGD grades and among different regions.

Ocular surface analysis and automatic non-invasive assessment of tear film breakup location, extension and progression in patients with glaucoma

Background

Tear film stability is the key event in ocular surface diseases. The purpose of this study is to evaluate spatial and temporal progression of the tear film breakup using an automatic non-invasive device.

Methods

Non-invasive tear breakup time (NITBUT) parameters, such as First NITBUT (F-NITBUT) and Average NITBUT (A-NITBUT), were evaluated in 132 glaucoma and 87 control eyes with the Keratograph 5 M device. Further analysis of this data was used to determine size, location and progression of tear film breakup with automatically identified breakup areas (BUA). The progression from First BUA (F-BUA) to total BUA (T-BUA) was expressed as Dry Area Growth Rate (DAGR). Differences between both groups were analysed using Student t-test for parametric data and Mann-Whitney U test for non-parametric data. Pearson’s correlation coefficient was used to assess the relationship between parametric variables and Spearman in the case of non-parametric variables.

Results

F-NITBUT was 11.43 ± 7.83 s in the control group and 8.17 ± 5.73 in the glaucoma group (P = 0.010). A-NITBUT was 14.04 ± 7.21 and 11.82 ± 6.09 s in control and glaucoma groups, respectively (P = 0.028). F-BUA was higher in the glaucoma group than in the control group (2.73 and 2.28; P = 0.022) and was more frequently located at the centre of the cornea in the glaucoma group (P = 0.039). T-BUA was also higher in the glaucoma group than in the control group (13.24 and 9.76%; P = 0.012) and the DAGR was steeper in the glaucoma group than in the control group (34.38° and 27.15°; P = 0.009).

Conclusions

Shorter NITBUT values and bigger, more central tear film breakup locations were observed in the glaucoma group than in the control group. The DAGR indicates that tear film rupture is bigger and increases faster in glaucomatous eyes than in normal eyes.

Morphological and cytological changes of meibomian glands in patients with type 2 diabetes mellitus

AIM

To observe the changes of microcellular structure of meibomian glands (MGs) in type 2 diabetes mellitus (DM), and to explore its correlation with the duration of diabetes.

METHODS

The study assessed 132 eyes of 132 patients with type 2 diabetes mellitus (DM group) and 100 eyes of 100 non-diabetic participants (NDM group). All patients underwent the examination of the Keratograph 5M system to obtain the meibography which were used to evaluate the structure dropout of the MGs. And then laser scanning confocal microscopy (LSCM) was performed for observing the acinar cells and ducts of the MGs to obtain the following parameters: the MG acinar unit density (MGAUD), MG acinar longest diameter (MGALD) and MG acinar shortest diameter (MGASD). The examination results of the right eye were selected for analysis.

RESULTS

Compared with that in NDM group, the meiboscore was significantly higher (Z=-4.057, P<0.001), and there were more MGs dropout in DM group. With the prolongation of the course of diabetes, the absence of MGs aggravated and the MGs dropout score increased (r=0.596; P<0.001). LSCM showed that there were various cytological alterations in acinar cells of MGs with the progress of diabetes duration, such as expansion, atrophy or fibrosis of MG acinar units, decreased density of MG acinar units, deposition of lipid substances, infiltration of inflammatory cells, proliferation of fibrous tissues, etc. And the opening of the glandular duct changed from smooth at the beginning to narrow, blocked, fibrotic and so on. Compared with that in NDM group, the MGAUD in DM group was significantly lower (Z=-9.713; P<0.001), the MGALD and MGASD were significantly larger (Z=-9.751, -6.416; P<0.001). With the duration of diabetes, the MGAUD reduced, the MGASD increased (r=0.860, 0.364, P<0.001); but the MGALD had no correlation with diabetic duration (r=0.133, P=0.151).

CONCLUSION

With the progress of diabetes, the meibomian glandular acinar cells of diabetic patients show various manifestations. Those changes may result in the dysfuction of the MGs, tear film instability and dry eye symptoms in patients with type 2 DM.

Racial and Ethnic Differences in the Association Between Diabetes Mellitus and Dry Eye Disease

Purpose:To examine the association between dry eye and diabetes mellitus among a large North Carolina patient population. Methods:A retrospective cross-sectional study of patients seen within the University of North Carolina medical system between July 1, 2008, and September 1, 2017, was performed. De-identified medical records contained within the Carolina Data Warehouse of adult patients who have had an ocular evaluation were studied. Four categories of disease states were identified by ICD-9 and ICD-10 codes. Patients were grouped based on being diagnosed with Dry Eye Disease (ICD-9: 375.15, 370.33, and ICD-10: H04.12, H16.221), Diabetes Mellitus (ICD-9: 250.00-250.93 and ICD-10: E08-E11, E13), neither, or both diseases. Odds ratios of the association between diabetes and dry eye were calculated for the following racial/ethnic groups: Non-Hispanic White, Non-Hispanic Black/African American, Asian, and Hispanic. Results:A total of 81,480 patients were included in the analysis; of those, 8978 patients had dry eye disease and 18,361 patients had diabetes. The remaining 54,141 patients had neither disease. Dry eye prevalence among patients with diabetes was 14.39% (95% CI: 13.89-14.91%) and 10.11% (95%CI: 9.88-10.35%) among patients without diabetes. The odds of a patient with diabetes having dry eye are 1.15 (95% CI: 1.09-1.21) times that of a patient without diabetes. Asian patients with diabetes demonstrated the highest odds of having dry eye at 1.49 (95% CI: 1.12-1.98). Conclusions:Dry eye is common among patients with diabetes, and the association between these diseases is strongest among Asian patients. Race and ethnicity are important demographic factors that may guide providers in the diagnosis and treatment of dry eye in the setting of diabetes.

Contact lens wear and the diabetic corneal epithelium: A happy or disastrous marriage?

Diabetes mellitus is an epidemic in the US and abroad. With the advent of new contact lens technology, the use of contact lenses as glucose sensors in lieu of the traditional finger stick is quickly becoming realized. This has the potential to rapidly expand the contact lens market into this growing patient population. The independent cellular and physiological effects of contact lens wear and diabetes on the corneal epithelium have been described. However, little evidence exists to date to support whether there is increased risk associated with contact lens wear in diabetes. The focus of this review is to discuss what is known about the cellular effects of contact lenses on the corneal epithelium, the pathophysiological changes in the corneal epithelium that occur in diabetes, and whether an increased risk for corneal epithelial damage and/or infection may negatively impact safety in diabetic contact lens wearers. Available data indicates that there are inherent risks associated with contact lens wear in diabetics. Importantly, eye care practitioners fitting contact lenses in the diabetic patient need to carefully consider the duration of disease, the level of glycemic control, the presence of retinopathy, and the patient's overall health.

Evaluation of a new artificial tear formulation for the management of tear film stability and visual function in patients with dry eye

Purpose

Artificial tears are the first line of therapy for dry eye disease (DED) and are also the most frequently used treatment approach for this common condition. Despite this, there are few published studies that directly compare the effectiveness of different drop preparations, especially those formulated specifically for dry eye. In this study, we tested a new artificial tear product, Rohto^® Dry-Aid™, for its ability to relieve the signs and symptoms of DED. The study used a second drop, Systane^® Ultra, as a positive comparator.

Materials and methods

This was a prospective, single-center, open-label, parallel-group study comparing the effects of the two products when used continuously over ~30 days (Clinical Trials registration number NCT03183089). Subjects were randomly assigned to one of the two test groups and were monitored 2 and 4 weeks after enrollment. Efficacy endpoints included ocular staining, visual function, and ocular discomfort.

Results

Treatment groups had similar ocular staining and ocular comfort scores, and both showed statistically significant ocular discomfort score improvement. Subjects in the Rohto group reported significant improvements in visual tasking activities such as watching television and driving at night. There was also a tendency for diary symptom scores to worsen from morning to evening in the Systane group, but not in the Rohto group; this trend was not significant, but warrants further study.

Conclusion

The two products, Rohto Dry-Aid and Systane Ultra, elicited comparable effects on the signs and symptoms of DED. While both products are designed to provide long-lasting relief, subjects in the Rohto group experienced a superior relief from discomfort associated with visual tasking activities and daily diaries, indicating that the Rohto drops may provide a longer duration of symptomatic relief over the course of the day.

Recovery of Corneal Sensitivity and Increase in Nerve Density and Wound Healing in Diabetic Mice After PEDF Plus DHA Treatment

Diabetic keratopathy decreases corneal sensation and tear secretion and delays wound healing after injury. In the current study, we tested the effect of treatment with pigment epithelium-derived factor (PEDF) in combination with docosahexaenoic acid (DHA) on corneal nerve regeneration in a mouse model of diabetes with or without corneal injury. The study was performed in streptozotocin-induced diabetic mice (C57BL/6). Ten weeks after streptozotocin injection, diabetic mice showed significant decreases of corneal sensitivity, tear production, and epithelial subbasal nerve density when compared with age-matched normal mice. After diabetic mice were wounded in the right eye and treated in both eyes with PEDF+DHA for 2 weeks, there was a significant increase in corneal epithelial nerve regeneration and substance P-positive nerve density in both wounded and unwounded eyes compared with vehicle-treated corneas. There also was elevated corneal sensitivity and tear production in the treated corneas compared with vehicle. In addition, PEDF+DHA accelerated corneal wound healing, selectively recruited type 2 macrophages, and prevented neutrophil infiltration in diabetic wounded corneas. These results suggest that topical treatment with PEDF+DHA promotes corneal nerve regeneration and wound healing in diabetic mice and could potentially be exploited as a therapeutic option for the treatment of diabetic keratopathy.