Ocular Surface Characteristics in Diabetic Children

Prevalence of dry eye syndrome in a South African diabetic paediatric population

BACKGROUND

Diabetes mellitus (DM) can be defined as a metabolic disorder that results from either the inability of insulin to perform its normal functions or decreased insulin secretion. Dry eye disease is a complex ailment of the tear film resulting in discomfort characterised by pain, a feeling of heavy eyes, grittiness, burning, dryness, itchiness, foreign body sensation, and visual disturbances. Patients with chronic conditions, i.e. DM, are more susceptible to developing dry eye due to various complications that may arise, such as, peripheral neuropathy, inflammatory alterations and reduced lacrimal gland function.

AIM

To identify the prevalence of dry eye syndrome in paediatric patients diagnosed with Diabetes Mellitus (Type 1/2).

METHOD

37 children with diabetes and 40 healthy, age group matched controls were enrolled in this study. Participants underwent a complete dry eye assessment in the following order: Ocular Surface Disease Index (OSDI) and McMonnies questionnaire, meibomian gland evaluation using white light, Tear Break-up Test (TBUT), Phenol Red Thread (PRT) test and Tear film Osmolarity test. Duration of diabetes was used as the parameter.

RESULTS

The incidence of dry eye syndrome was found to be higher among diabetics, with 15 (40.5 %) from the diabetic population compared to 4 (10.0 %) from the control group. TBUT and PRT test values were significantly reduced in children with diabetes (p < 0.001). TFO values were higher in the diabetics. No statistically significant differences were found the questionnaire scores, of the two groups, however the diabetic group appeared to be less symptomatic.

CONCLUSION

Dry eye is more common in the diabetic paediatric population. TBUT and PRT results were found to be lower in diabetics. Results showed a strong correlation between duration of diabetes and TBUT values. Healthcare practitioners, working with children diagnosed with diabetes, should raise awareness as well as encourage early dry eye screening and intervention.

CLINICAL SIGNIFICANCE

Due to the steady increase in the number of children and adolescents with diabetes, the characteristics and prevalence of dry eye syndrome in this population has become more valuable.

A Comparative Study of Ocular Surface Disease in Childhood Glaucoma

PURPOSE

To evaluate ocular surface disease (OSD) in patients with childhood glaucoma (CG).

METHODS

A multicenter, comparative, cross-sectional study of 41 eyes of 27 patients with CG and 42 eyes of 42 healthy age- and sex-matched controls was conducted between 2021 and 2022. Developmentally delayed children and those having a coexisting systemic illness that might affect the ocular surface were not enrolled. Data collected included glaucoma type, glaucoma medications and surgeries, anterior segment examination, symptom frequency and severity, and tear break-up time (TBUT). Dry eye disease (DED) symptoms were evaluated using an Arabic-language SPEED questionnaire.

RESULTS

The average number of glaucoma medications and surgeries among the 27 patients with CG was 1.17 and 1.4, respectively. TBUT was shorter in patients with CG compared with controls and even shorter when glaucoma medication usage was accounted for. Punctate epithelial erosions were more prevalent in patients with CG and of a higher grade. The severity of all DED parameters, and the prevalence of all DED parameters except for eye fatigue, were greater in patients with CG on the day of questionnaire intake. In addition, each additional glaucoma drop was associated with worse TBUT and ocular surface dryness. All analyses mentioned above were statistically significant (P < 0.05).

CONCLUSIONS

In this first study to comprehensively evaluate OSD in patients with CG, a significantly greater incidence of OSD signs and symptoms was found in patients with CG compared with a healthy population. Additional study by CG subtype is needed.

Evaluation of Dry Eye Disease Characteristics of Children With Type 1 and Type 2 Diabetes Mellitus and MODY

PURPOSE

To assess dry eye disease characteristics of pediatric patients with diabetes.

METHODS

Twenty-one patients with type-1 diabetes mellitus (DM), 20 with type-2 DM, 19 with maturity-onset diabetes of the young (MODY), and 20 control participants were included in the study. Ocular Surface Disease Index (OSDI) questionnaire, tear film break-up time (TBUT) analysis, Schirmer test with anesthesia, and conjunctival impression cytologic analysis were performed.

RESULTS

In Group 1, the Schirmer test and TBUT values were lower than the control group. In groups 1 to 3, OSDI scores were higher than the control group. In Groups 1 and 2, the goblet cell density was lower than the control group.

CONCLUSIONS

Dry eye parameters of all three diabetic groups were adversely affected in favor of dry eye disease. Children with MODY have increased OSDI scores. Alterations in the conjunctival impression cytology were observed more prominently in patients with type-1 DM.

Dry eye disease in the young: A narrative review

Dry eye disease (DED), a multifactorial ocular disease that significantly impacts quality of life, is most commonly reported in adults. This review describes the prevalence, risk factors, diagnosis and management of DED in children. A literature search, conducted from January 2000-December 2022, identified 54 relevant publications. Using similar diagnostic criteria to those reported in adults, namely standardized questionnaires and evaluation of tear film homeostatic signs, the prevalence of DED in children ranged from 5.5% to 23.1 %. There was limited evidence for the influence of ethnicity in children, however some studies reported an effect of sex in older children. Factors independently associated with DED included digital device use, duration of digital device use, outdoor time and urban living, Rates of DED were higher in children with ocular allergy and underlying systemic diseases. Compared with similar studies in adults, the prevalence of a prior DED diagnosis or a diagnosis based on signs and symptoms was lower in children, but symptoms were commonly reported. Treatment options were similar to those in adults, including lifestyle modifications, blinking, management of lid disease and unpreserved lubricants in mild disease with escalating treatment with severity. Management requires careful exploration of symptoms, medical history and the diagnosis and management of ocular comorbidities such as allergy and anterior blepharitis. Appropriately powered population-based studies are required to understand the prevalence of and risk factors for DED in children. Development of age-appropriate thresholds for signs and symptoms of DED would support better diagnosis of disease and understanding of natural history.

The effect of a-Lipoic acid (ALA) on oxidative stress, inflammation, and apoptosis in high glucose-induced human corneal epithelial cells

PURPOSE

Oxidative stress and inflammation had been proved to play important role in the progression of diabetic keratopathy (DK). The excessive accumulation of AGEs and their bond to AGE receptor (RAGE) in corneas that cause the formation of oxygen radicals and the release of inflammatory cytokines, induce cell apoptosis. Our current study was aimed to evaluate the effect of ALA on AGEs accumulation as well as to study the molecular mechanism of ALA against AGE-RAGE axis mediated oxidative stress, apoptosis, and inflammation in HG-induced HCECs, so as to provide cytological basis for the treatment of DK.

METHODS

HCECs were cultured in a variety concentration of glucose medium (5.5, 10, 25, 30, 40, and 50 mM) for 48 h. The cell proliferation was evaluated by CCK-8 assay. Apoptosis was investigated with the Annexin V- fluorescein isothiocyanate (V-FITC)/PI kit, while, the apoptotic cells were determined by flow cytometer and TUNEL cells apoptosis Kit. According to the results of cell proliferation and cell apoptosis, 25 mM glucose medium was used in the following HG experiment. The effect of ALA on HG-induced HCECs was evaluated. The HCECs were treated with 5.5 mM glucose (normal glucose group, NG group), 5.5 mM glucose + 22.5 mM mannitol (osmotic pressure control group, OP group), 25 mM glucose (high glucose group, HG group) and 25 mM glucose + ALA (HG + ALA group) for 24 and 48 h. The accumulation of intracellular AGEs was detected by ELISA kit. The RAGE, catalase (CAT), superoxide dismutase 2 (SOD2), cleaved cysteine-aspartic acid protease-3 (Cleaved caspase-3), Toll-like receptors 4 (TLR4), Nod-like receptor protein 3 (NLRP3) inflammasome, interleukin 1 beta (IL-1 ß), and interleukin 18 (IL-18) were quantified by RT-PCR, Western blotting, and Immunofluorescence, respectively. Reactive oxygen species (ROS) production was evaluated by fluorescence microscope and fluorescence microplate reader.

RESULTS

When the glucose medium was higher than 25 mM, cell proliferation was significantly inhibited and apoptosis ratio was increased (P < 0.001). In HG environment, ALA treatment alleviated the inhibition of HCECs in a dose-dependent manner, 25 μM ALA was the minimum effective dose. ALA could significantly reduce the intracellular accumulation of AGEs (P < 0.001), activate protein and genes expression of CAT and SOD2 (P < 0.001), and therefore inhibited ROS-induced oxidative stress and cells apoptosis. Besides, ALA could effectively down-regulate the protein and gene level of RAGE, TLR4, NLRP3, IL-1B, IL-18 (P < 0.05), and therefore alleviated AGEs-RAGE-TLR4-NLRP3 pathway-induced inflammation in HG-induced HCECs.

CONCLUSION

Our study indicated that ALA could be a desired treatment for DK due to its potential capacity of reducing accumulation of advanced glycation end products (AGEs) and down-regulating AGE-RAGE axis-mediated oxidative stress, cell apoptosis, and inflammation in high glucose (HG)-induced human corneal epithelial cells (HCECs), which may provide cytological basis for therapeutic targets that are ultimately of clinical benefit.

Long-term changes in the ocular surface during orthokeratology lens wear and their correlations with ocular discomfort symptoms

PURPOSE

To evaluate the changes in ocular surface parameters during orthokeratology lens wear and determine their correlations with ocular discomfort symptoms.

METHODS

Fifty individuals were enrolled in this prospective pilot study. Clinical evaluation of the ocular surface included the ocular surface disease index, slit-lamp examination, Keratograph 5M, optical quality analysis system, and corneal staining. After baseline examinations, clinical tests were performed at 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months after orthokeratology lens wear. Correlations between ocular discomfort symptoms and signs of ocular discomfort were evaluated.

RESULTS

Overall ocular surface disease index score and two subscale scores (ocular symptoms and vision-related function) significantly increased at the 3-month visit (P < 0.05), and decreased to levels close to baseline at the12-month visit (P > 0.05). The basic objective scatter index and the mean tear film objective scatter index increased, peaking at 3-month visit (P < 0.05) and gradually decreased thereafter. The modulation transfer function cut-off significantly decreased at the 3-month visit (P < 0.05). During the 12-month study period, the overall ocular surface disease index score and vision-related function score were significantly and positively correlated with the basic objective scatter index and mean tear film objective scatter index (P < 0.05). After 1 week of lens wear, Grade 1 corneal staining increased to 16.4 %, mostly involving the central and inferior cornea.

CONCLUSIONS

Orthokeratology lens wear increased ocular discomfort symptoms and decreased the function of tear film, mainly within 3 months of lens wear. Tear-related visual function parameters were correlated with ocular discomfort. A new parameter, tear film objective scatter index, measured with the optical quality analysis system, was more sensitive in detecting the quality and stability of tear film than traditional indicators.

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.

Changes in Tear Meniscus Analysis of Children Who Have Type 1 Diabetes Mellitus, With and Without Vitamin D Deficiency

PURPOSE

The aim of this study was to quantitatively evaluate dry eye test parameters of pediatric patients with and without vitamin D deficiency (VDD) in type 1 diabetes mellitus.

METHODS

In this prospective cross-sectional study, the Ocular Surface Disease Index, Schirmer test, tear film breakup time, corneal staining score, and anterior segment optical coherence tomography were used to determine the dry eye test parameters of pediatric patients with type 1 diabetes mellitus (T1-DMPs) (group 1) and a healthy pediatric control group (group 2). Group 1 was divided into 2 subgroups based on their vitamin D status: group 1a, who had a VDD, and group 1b, who had vitamin D levels that were within the normal range.

RESULTS

This study compared 90 eyes of 90 pediatric T1-DMPs with 80 eyes of 80 healthy controls. The demographic characteristics of the groups were similar ( P > 0.05). The tear film breakup time, Schirmer test, corneal staining score, and values of the tear meniscus height and area were observed to have been lower in the patients in group 1a than the healthy pediatric control group, at P < 0.001. The same parameters were statistically significantly lower in the patients in group 1a when compared with group 1b ( P < 0.05 for both).

CONCLUSIONS

The tear measurements of the pediatric T1-DMPs were lower than those in the healthy pediatric control group. The accompanying VDD made this situation more pronounced.

Smartphone gaming induces dry eye symptoms and reduces blinking in school-aged children

Purpose

Smartphone use by children is rising rapidly, but its ocular surface impact is unknown. This study examined the effect of smartphone use on blinking, symptoms, and tear function in children.

Methods

Prospective intervention study where 36 children aged 6–15years (14 M:22 F) played games on a smartphone continuously for one hour. Symptoms (SANDE, IOSS, NRS) and tear film (lipid layer thickness, tear secretion, stability) were assessed before and after gaming. Blink rate and interblink interval were measured in situ using an eye tracking headset, before (during conversation) and continuously throughout gaming. Symptoms and tear film changes were examined using paired t-tests. Changes in blinking throughout one hour were examined using repeated measures ANOVA, post-hoc comparisons with Bonferroni correction. Associations examined using Pearson bivariate correlation. Significance level was 0.05.

Results

Symptoms worsened following one hour smartphone gaming (SANDE + 8.2units, p = 0.01; IOSS + 1.3units, p < 0.001; NRS-average +6.3units, p = 0.03; NRS-comfort +7.6units, p = 0.04; NRS-tiredness +10.1units, p = 0.01), but tear film remained unchanged. Blink rate reduced from 20.8 blinks/min to 8.9 blinks/min (p < 0.001) and interblink interval increased from 2.9 s to 8.7 s (p = 0.002) within the first minute of gaming relative to baseline conversation, and this effect remained unchanged throughout one hour of gaming.

Conclusions

Smartphone use in children results in dry eye symptoms and immediate and sustained slowing of blinking, with no change in tear function evident up to one hour. Given the ubiquitous use of smartphones by children, future work should examine whether effects reported herein persist or get worse over a longer term causing cumulative damage to the ocular surface.

A Cross-Sectional Study of Ocular Changes in Children and Adolescents with Diabetes Mellitus in Selected Health Facilities in Ghana

BACKGROUND

The main objective of the study was to determine the prevalence of diabetic retinopathy (DR), other diabetes-related ocular changes (e.g., cataracts, corneal ulceration), and non-diabetic ocular disease in Ghanaian children and adolescents. The second objective was to evaluate the relationship between these conditions and age at diagnosis, current age, diabetes mellitus (DM) duration, and participant's sex.

METHODS

A cross-sectional study, undertaken by a multidisciplinary team, included a cohort of children and adolescents (4-19 years) with DM recruited from selected health facilities in Ghana, from March 2016 to September 2019, after written informed consent or assent. The cohort will be followed up for 3 years to determine the natural course of the ocular changes, reported later. Participants were examined for all microvascular and macrovascular complications, non-diabetic ocular disease, anthropometric measurements, laboratory characteristics and quality of life issues. Full ocular examination was also undertaken. Statistical Package for Social Sciences (SPSS Version 25.0) was used for the data analysis. Continuous and categorical variables were presented as mean and standard deviation (SD), median (interquartile range) and as percentages (%), respectively. T-test and Mann-Whitney U test were used in establishing associations.

RESULTS

A total of 58 participants were recruited. DR was detected in only 1 out of 58 (1.7%) participants at baseline. Cataracts were the most common ocular finding, detected in 42 (72%) at baseline. Other anterior segment changes observed included blepharitis 46 (79.3%) and tear film instability 38 (65.5%). There was a significant positive association between duration of the DM and the risk of cataract (p = 0.027). Participants' age at diagnosis was significantly associated with the presence of prominent corneal nerves (p = 0.004).

CONCLUSIONS

DR was uncommon in this cohort of young persons with DM in Ghana. Cataracts, blepharitis and refractive errors were ocular changes commonly observed. All young persons with diabetes should undergo regular eye examination in all clinics where follow-up care is provided.

Analysis of Tear Function Outcomes following Collagen Cross-Linking Treatment in Ectatic Corneas

Purpose

To analyze tear function outcomes following collagen cross-linking (CXL) treatment in ectatic corneas.

Methods

Fifty-seven eyes of 34 patients were included, and patients with keratoconus who underwent epithelium-on (epi-on) or epithelium-off (epi-off) CXL were evaluated. The following tests were performed preoperatively and at 1, 3, 6, and 12 months postoperatively: best-corrected visual acuity (BCVA), maximum keratometry value (Kmax), ocular surface disease index (OSDI) questionnaire, slit-lamp examination, tear meniscus height, first noninvasive Keratograph breakup time (1st NIKBUT), average NIKBUT, and bulbar redness.

Results

BCVA improved in both epi-on and epi-off groups at most follow-up points, but was not significantly different between groups. At 12-month follow-up, Kmax in the epi-on and epi-off groups improved after CXL, but there was no significant difference between the groups. The OSDI in both groups decreased after operation compared with before surgery, and there was no significant difference between the two groups. Comparing the two groups, only the change in the tear meniscus height at 6 months postoperatively was statistically significant, and the pre- and postoperative values of the two groups were within the normal range (>0.20 mm). The change was small and had no clinical significance. There was no change in the 1st NIKBUT and average NIKBUT between the epi-on and epi-off groups. A change in bulbar redness was significantly better in the epi-off group than in the epi-on group at 3 months postoperatively. Comparing the effects at 1 year postoperatively, both groups had positive results in OSDI, NIKBUT, tear meniscus height, and bulbar redness.

Conclusion

Both epi-on and epi-off CXL can control the progression of keratoconus, although epi-off CXL is more effective. Both methods have a positive effect on dry eye, which can improve the condition of the tear film and reduce dry eye symptoms in patients with keratoconus.

Ocular surface alterations and changes of meibomian glands with meibography in type 1 diabetic children

PURPOSE

To observe the changes of the ocular surface and meibomian glands by non-contact meibography in patients with type 1 diabetic children.

METHODS

A total of forty-three patients with type 1 diabetic children and 43 age-matched healthy subjects were included in the study. The ocular surface disease index (OSDI) questionnaire, invasive tear film break-up time (TF-BUT), fluorescein staining of the ocular surface and Schirmer II test were performed for all participants. Ocular surface and lid margins were evaluated by slit lamp. Non-contact meibography was performed with the Phoenix-Meibography module in Sirius corneal topographic device.

RESULTS

Both groups consisted of 25 (58.1%) female and 18 (41.9%) male children and the mean age was 14.4 ± 2.5 years. In the T1DM group, the mean disease duration was 6.8 ± 3.1 years. The mean TF-BUT (p = 0.002) and Schirmer II test (p = 0.007) measurements were lower in the diabetic group than those of in controls. Total eyelid score (p = 0.027) and meibomian gland (MG) secretion score (p = 0.007) were significantly high in diabetic children. MG area loss was also significantly high in both lower and upper eyelid (p < 0.001). In morphological analyses of meibomian glands thinning, shortening and presence of ghost areas (p = 0.05, p = 0.027 and p = 0.000, respectively) were more common in the diabetic group. There was no correlation between both lower and upper eyelid meiboscores and disease duration (p = 0.51 and p = 0.61), BMI (p = 0.08 and p = 0.51), serum HbA1c level (p = 0.06 and p = 0.49) and IGF-1 SDS (p = 0.38 and p = 0.68).

CONCLUSION

The study revealed that the MG loss area increases and morphological alterations of meibomian glands occur in type 1 diabetic children. Disease duration and metabolic control of diabetes do not affect meibography measurements.

CLINICAL TRIALS REGISTRATION

The study was organized in accordance with the ethical standards settled by the Ethics Committee of Faculty of Medicine, Afyonkarahisar Health Sciences University.

TRIAL REGISTRATION NUMBER

2011-KAEK-2, 2021/106.

TRIAL REGISTRATION DATE

02.05.2021.

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.

Incidence and Risk Factors of Dry Eye in Children and Adolescents With Diabetes Mellitus: A 3-Year Follow-Up Study

Purpose: To investigate the incidence and risk factors of dry eye in children with diabetes mellitus (DM) over a period of 3 years. Methods: Children and adolescents with DM (age: 3-14 years) from the Shanghai Children and Adolescent Diabetes Eye (SCADE) study cohort who did not have dry eye in January 2018 were followed-up for 3 years and re-examined in January 2021, and the incidence rate and risk factors for dry eye were calculated. Results: Forty children and adolescents with DM came for follow-up in 2021. Nine of them were diagnosed with dry eye, resulting in a 3-year incidence rate of 22.5% and an annual mean incidence rate of 7.5% for dry eye. Univariate regression analysis confirmed that decreased corneal sensation (OR [Odds Ratio] = 25.60; 95%CI [Confidence Interval] = 1.31~501.69; P = 0.03) was the risk factor for dry eye incidence. Long course of DM (OR = 1.80; 95%CI = 0.96~3.38; P = 0.07), eye pain (OR = 12.27; 95%CI = 0.65~231.48; P = 0.09), and dry eye in parents (OR = 15.99; 95%CI = 0.76~337.75; P = 0.08) may interfere with the incidence of dry eye in them. Conclusions: The incidence of dry eye in children and adolescents with DM is high.

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.

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.

Dry eye symptoms in children: can we reliably measure them?

PURPOSE

Many dry eye questionnaires are available, but these may not be suitable for paediatric eye care. The feasibility of use and repeatability of symptom questionnaires administered to children was examined.

METHODS

Participants aged 6-15 years (n = 62; 25M:37F; 40% male) completed six questionnaires twice in random order at a single visit: Symptoms assessment in dry eye (SANDE), ocular surface disease index (OSDI), numerical rating scale (NRS), ocular comfort index (OCI, n = 30), dry eye questionnaire 5 (DEQ-5) and the instant ocular symptoms survey (IOSS). Completion time and need for assistance were recorded and relationships with age examined (Pearson correlation, independent t-test). The number of participants requiring assistance and with which items were compared (linear mixed model, pairwise test). Repeatability (coefficient of repeatability (CoR), limit of agreement, bias) and intraclass correlation coefficient (ICC) were examined.

RESULTS

Completion time was ≤2 min for each individual questionnaire. Younger participants took longer to complete (r = -0.43 to -0.60, p ≤ 0.01), and required more assistance (p ≤ 0.001). Forty-eight participants required assistance with at least one questionnaire. Older children (13-15 years) only required assistance with OSDI (p ≤ 0.004) and NRS (p ≤ 0.003). Participants required more assistance with SANDE, OSDI and NRS than with DEQ-5 and IOSS (p ≤ 0.02) and with gritty (OSDI, 77% of participants; OCI, 100%) and foreign body sensation (NRS, 92%) items. CoR was similar for all questionnaires with no evidence of a learning effect (p > 0.05). ICC was moderate to excellent.

CONCLUSIONS

Dry eye questionnaires can be used reliably in paediatric eye care; more time and assistance may be required for younger children. The DEQ-5 and IOSS are recommended for use in younger age children.

The Effect of 0.01% Atropine Eye Drops on the Ocular Surface in Children for the Control of Myopia-The Primary Results from a Six-Month Prospective Study

Purpose

To evaluate the effect of 0.01% atropine eye drops on the ocular surface in children for the control of myopia.

Methods

A total of 72 participants were recruited for this prospective study. Prior to and after 1, 3, and 6 months of 0.01% atropine administration, an ocular surface disease index (OSDI) questionnaire was obtained, Keratograph 5M was used for the measurement of the tear meniscus height (TMH), noninvasive keratographic tear film break-up time (NK-BUT, the first keratographic break-up time, [NK-BUT_first] and the average keratographic break-up time, [NK-BUT_ave]), bulbar redness (BR), meiboscore (MS), and anterior segment optical coherence tomography (AS-OCT) was used to calculate the inferior tear meniscus area (TMA).

Results

After using the 0.01% atropine eye drops for 1 month, 9 subjects complained of discomfort immediately after administration, but this quickly subsided, and 1 subject was temporarily dazzled. All the ocular surface symptoms were mild and occurred rarely. After 3 months, these complaints no longer occurred. Compared with the baseline values, the OSDI scores (0.08 ± 0.28), values of TMH (0.23 ± 0.04 mm), TMA (0.0420 ± 0.0444 mm²), NK-BUT_first (9.39 ± 5.25 s), NK-BUT_ave (10.49 ± 4.94 s), BR (0.63 ± 0.37), and MS (0.89 ± 0.70) did not change significantly after 6 months of 0.01% atropine eye drop administration (P > 0.05).

Conclusion

In this 6-month prospective study, no side effects were observed on the ocular surface after using 0.01% atropine in children.

The role of meibography in ocular surface diagnostics: A review

The meibomian glands are lipid-secreting glands located in the tarsal plates, whose secretory products cover the tear film, thereby reducing evaporation as well as ensuring lubrication of the ocular surface. The meibomian glands can be visualized at different levels of magnification by infrared meibography, laser confocal microscopy, and optical coherence tomography. These imaging modalities have been subject to much research and progress in clinical practice and have shaped our current understanding of meibomian glands in health and disease. In this review, we explore the evolution of meibography over the past decades, the major contributions of various meibographic modalities, and discuss their clinical significance.

Alterations of Tear Film and Ocular Surface in Children with Type 1 Diabetes Mellitus

Purpose: To investigate whether diabetes mellitus (DM) affects ocular surface of children with well-controlled type 1 DM.Methods: Sixty-five diabetic patients and 55 age-matched controls enrolled to study. Detailed ocular surface assessment including, ocular surface disease index (OSDI) questionnaire, tear film break-up time (TBUT) analysis, Schirmer test, and conjunctival impression cytologic analysis were performed.Results: Schirmer test and TBUT results were significantly lower in DM group than controls (p = 0.001, for all). OSDI scores of all participants were within normal range. Impression cytology analysis showed grade 0 changes in all participants and there was no difference between groups for goblet cell density (p > 0.05). The TBUT results were significantly associated with duration of DM (r = -0.309, p = 0.036).Conclusion: Diabetic children without symptoms, signs, and definite diagnosis of dry eye still had lower TBUT and Schirmer test results than controls; however, impression cytology analysis was similar in both groups.

Diabetes mellitus is associated with dry eye syndrome: a meta-analysis

BACKGROUND

Dry eye is the most common eye disorder of tears and ocular surface. However, the extent to which diabetes mellitus may confer risk of dry eye remains uncertain. The aim of this study was to perform a meta-analysis that synthesizes the association between diabetes mellitus and dry eye.

METHODS

Case-control studies were selected from the Medline, Embase, Cochrane database from January 2000 to March 2018. Two reviewers screened potential studies, and eligible studies were included according to keywords and predefined criteria. We calculated the overall risk estimates by using a fixed-effect model or a random-effects model in relation to heterogeneity.

RESULTS

A total of four studies were included in our meta-analysis consisting of 2,504,794 persons. Our study showed a significant association between diabetes mellitus and the risk of dry eye syndrome (OR 1.30; 95% CI 1.08-1.57; P value = 0.006). However, the heterogeneity was observed (P value < 0.001, I² = 95.2%).

CONCLUSION

Our meta-analysis suggests that diabetes mellitus has a significant association with the risk of dry eye. However, this result is limited by heterogeneity. Further prospective and concise studies are needed to confirm the association between diabetes mellitus and dry eye.

The Influence of Overnight Orthokeratology on Ocular Surface and Meibomian Gland Dysfunction in Teenagers with Myopia

Purpose

The aim of this study was to investigate the effect of overnight orthokeratology (OOK) on ocular surface and meibomian gland dysfunction in teenagers with myopia.

Methods

A total of 59 subjects were recruited in this prospective study. The following tests were performed before and after 1, 3, 6, 12, and 24 months of OOK lens wear, including ocular surface disease index (OSDI) questionnaire, slit-lamp examination, and Keratograph 5M.

Results

No infectious keratitis occurred during the study. OSDI scores increased gradually and reached the maximum at 6 months of OOK wear (P < 0.001). The meniscus height was significantly increased at 1 and 3 months after the initiation of OOK (P=0.006, P=0.035). The corneal fluorescein staining at 1, 3, 6, 12, and 24 months after wearing OOK were all increased than the prewearing level with significant difference (P=0.014, P=0.036, P < 0.001, P < 0.001, and P=0.008, respectively). The first and the average tear film NIKBUT were all higher than the prewearing level, but there was no significant difference between every follow-up time points (P > 0.05). The lid margin abnormalities were significantly increased (P=0.003, P=0.038, and P=0.015) at 6, 12, and 24 months after the initiation of OOK. There was no significant difference in the meibomian gland orifice scores at each follow-up time points compared to the prewearing level (P > 0.05). The meibomian gland lipid secretion scores after wearing OOK were higher than those of the prewearing level, however, without statistically significant difference (P > 0.05). No significant differences of the degree of difficulty of lipid excretions were detected after the initiation of OOK (P > 0.05). There was no significant difference in meibomian gland dropout scores between all follow-up time points and the prewearing level (P=1.000).

Conclusion

OOK increased the symptoms of dry eye and decreased the function of tear film by affecting the meniscus height and BUT. OOK did not affect the function of meibomian glands.Clinical Study registration number: ChiCTR18000185708.

The ocular surface in children: A review of current knowledge and meta-analysis of tear film stability and tear secretion in children

PURPOSE

A review of ocular surface and meta-analysis of tear stability (tear break up time, TBUT) and tear secretion (Schirmer test) values in healthy children was conducted.

METHODS

Articles published between 1996 and 2017 indexed on MEDLINE, PubMed, Embase, Scopus and Google Scholar were retrieved using defined search terms. Statistical analysis (including sensitivity analysis and meta-regression) was performed.

RESULTS

23 studies were summarised (5,291 participants; neonates (0-29 days), infants (1 month - 1 year) or children (1-18 years) and a meta-analysis conducted using 15 eligible studies (1,077 participants). The combined mean TBUT in children was 14.64 seconds (s) (95% CI, 11.64, 17.64) and 21.76 s (95% CI, 20.43, 23.09) for sodium fluorescein TBUT and non-invasive TBUT respectively (NIBUT). The combined mean NIBUT was 32.5 s (95% CI, 31.78-33.22) in neonates. The combined mean Schirmer I with and without anesthesia were 16.26 mm/5 min (95% CI, 13.17, 19.36) and 29.30 mm/5 min (95% CI, 27.65, 30.96) in children and 9.36 mm/5 min (95% CI, 6.54, 12.18) and 17.63 mm/5 min (95% CI, 12.03, 23.23) in neonates. Meta-regression showed a significantly lower TBUT in children from studies conducted in Asia (p = 0.004).

CONCLUSION

There is paucity of data on ocular surface variables in healthy children, making it difficult to draw valid comparisons with adult values.

Diabetic complications in the cornea

Diabetic corneal alterations, such as delayed epithelial wound healing, edema, recurrent erosions, neuropathy/loss of sensitivity, and tear film changes are frequent but underdiagnosed complications of both type 1 (insulin-dependent) and type 2 (non-insulin-dependent) diabetes mellitus. The disease affects corneal epithelium, corneal nerves, tear film, and to a lesser extent, endothelium, and also conjunctiva. These abnormalities may appear or become exacerbated following trauma, as well as various surgeries including retinal, cataract or refractive. The focus of the review is on mechanisms of diabetic corneal abnormalities, available animal, tissue and organ culture models, and emerging treatments. Changes of basement membrane structure and wound healing rates, the role of various proteinases, advanced glycation end products (AGEs), abnormal growth and motility factors (including opioid, epidermal, and hepatocyte growth factors) are analyzed. Experimental therapeutics under development, including topical naltrexone, insulin, inhibitors of aldose reductase, and AGEs, as well as emerging gene and cell therapies are discussed in detail.