Tear Film Dysfunction Research Articles

A COMPARATIVE STUDY OF PRE-CORNEAL TEAR FILM BETWEEN DIABETICS AND NON-DIABETICSUSING OCULAR SURFACE DISEASE INDEX

Purpose: To determine distinctive characteristics of pre-corneal tear film in eyes of diabetics and compare them with non-diabetics. Design: Hospitalbasedobservationalcross-sectional study. Methods: The study was done in thedepartmentofophthalmology from July2022-December2023. Patients presenting to outpatient department of ophthalmology who were of age>45 years, have a history of diabetes for more than three years and those without diabetes as control groups were chosen.300patients weretaken forthestudyand dividedinto two groups(150 diabetics and 150 non-diabetics). Sample size was decided based on a convenient sampling method.Ocular surface disease index(OSDI) questionnaire was used to assess symptoms and signs.Corneal sensitivity test, Tear film breakup time(TBUT) and Schirmer tests were done. The corneal and conjunctival stains were used. Chi-square test was used to examine outcomes. Other tests were applied accordingly. Results: Diabetic patients had poorer OSDI scores compared to Non-diabetic patients(p 0.001*). Patients with diabetes had reduced corneal sensitivity(p<0.05*). Schirmer II and TBUT values were significantly prolonged in Diabetics compared to Non-diabetcs(p<0.05*). Duration of diabetes significantly increased the severity of dry eye. Dry eye was more prevalent in diabetic retinopathy patients(p=0.02*). Strong association was found between HbA1C and severity of diabetic retinopathy with P<0.05*. Conclusion:The duration of diabetes and stage of retinopathy are closely linked to the occurrence and severity of tear film dysfunction. Early detection and treatment are vital for preventing dry eye syndrome and its potential progression to vision-threatening complications, through simple non-invasive methods.

A Comparative Study of Tear Film Dysfunction After Small Incision Cataract Surgery and Phacoemulsification

A Comparative Study of Tear Film Dysfunction After Small Incision Cataract Surgery and Phacoemulsification

OPPORTUNITIES FOR IMPROVING THE LONG-TERM MANAGEMENT OF KERATOCONUS PATIENTS

Background and Objective: This study determined whether practitioners specializing in keratoconus (KC) adhere to published guidelines for disease management and to what extent comorbid conditions of dry eye, contact lens tolerance, and psychological consequences of KC are formally assessed as part oflong-term management. Materials and Methods: This cross-sectional study used an IRB-approved, Internet-based, REDCap platform. Descriptive statistics are presented. Results: A total of 222 participants qualified for participation. Most 134 (60%) followed young and unstable patients every 6 months and less frequent follow-up examinations for patients with stable findings, with 142 (64%) recommending annual examinations. Scleral lenses were the preferred optical correction method (36%), followed by corneal gas-permeable lenses (21%). A total of 118 (55%, n=216) participants recommend crosslinking to any patient with documented disease progression regardless of age. Fewer than 25% of patients were referred for surgical correction of KC. Half of respondents, 114 (51%), reported testing for tear film dysfunction, while 108 (49%) never tested. No participants used a depression screening instrument. Conclusion: Practitioners managing patients with KC largely adhere to current consensus recommendations. This survey identified several potentially high-impact, low-cost improvements to current practice patterns, including screening for dry eye and depression.

Novel nanostructured lipid carriers loading Apigenin for anterior segment ocular pathologies

Dry eye disease (DED) is a chronic multifactorial disorder of the ocular surface caused by tear film dysfunction and constitutes one of the most common ocular conditions worldwide. However, its treatment remains unsatisfactory. While artificial tears are commonly used to moisturize the ocular surface, they do not address the underlying causes of DED. Apigenin (APG) is a natural product with anti-inflammatory properties, but its low solubility and bioavailability limit its efficacy. Therefore, a novel formulation of APG loaded into biodegradable and biocompatible nanoparticles (APG-NLC) was developed to overcome the restricted APG stability, improve its therapeutic efficacy, and prolong its retention time on the ocular surface by extending its release. APG-NLC optimization, characterization, biopharmaceutical properties and therapeutic efficacy were evaluated. The optimized APG-NLC exhibited an average particle size below 200 nm, a positive surface charge, and an encapsulation efficiency over 99 %. APG-NLC exhibited sustained release of APG, and stability studies demonstrated that the formulation retained its integrity for over 25 months. In vitro and in vivo ocular tolerance studies indicated that APG-NLC did not cause any irritation, rendering them suitable for ocular topical administration. Furthermore, APG-NLC showed non-toxicity in an epithelial corneal cell line and exhibited fast cell internalization. Therapeutic benefits were demonstrated using an in vivo model of DED, where APG-NLC effectively reversed DED by reducing ocular surface cellular damage and increasing tear volume. Anti-inflammatory assays in vivo also showcased its potential to treat and prevent ocular inflammation, particularly relevant in DED patients. Hence, APG-NLC represent a promising system for the treatment and prevention of DED and its associated inflammation.

Impact of Dyslipidemia on Tear Film and Meibomian Gland Dysfunction: A Cross-Sectional Study of the Interplay between Serum Lipid Profile and Ocular Surface Health.

To determine the relationship between dyslipidemia and dry eye disease (DED), as well as its influence on tear film and meibomian glands. This cross-sectional study included 40 patients with a mean age of 35.2 ± 13.9 years without any history of dyslipidemia. DED and serum lipid profile were evaluated after 8 hours of fasting. Patients were classified according to serum lipid levels with the following cut-off values: total cholesterol (TC) (200 mg/dl), high-density lipoprotein (HDL) (40 mg/dl), low-density lipoprotein (LDL) (130 mg/dl), and triglycerides (TG) (150 mg/dl). The relationship between serum lipid levels and DED was analyzed with the following variables: dry eye questionnaire-5 (DEQ-5), first (F-NIBUT) and average (A-NIBUT) noninvasive breakup time, tear meniscus height (TMH), lipid layer grade (LLG), conjunctival bulbar redness (CBR), and upper (U-LAMG) and lower (L-LAMG) loss area of meibomian glands. Regarding tear film, patients with elevated TC and LDL levels reported significantly higher DEQ-5 scores and TMH (P < 0.05), while those with lower HDL levels showed significantly higher LLG (p < 0.05). Regarding MGD, patients with elevated TC, LDL, and TG, as well as lower HDL levels showed significantly higher L-LAMG (p < 0.05). HDL was correlated with LLG (p < 0.05), while TC was correlated with TMH (p < 0.05) and L-LAMG (p < 0.05), respectively. Disorders in TC, HDL, LDL, and TG levels were associated with DED, having an impact on the tear film and meibomian glands, specifically in DEQ-5 scores, LLG, and L-LAMG.

Post-Blink Blur Time-A Simple Test to Detect Dry Eye-Related Visual Disturbances.

Background: Dry eye disease (DED) stands out as one of the most common eye conditions encountered in clinical settings. This study aimed to determine the diagnostic ability and feasibility of post-blink blur time (PBBT) in detecting patients with DED symptoms. Methods: The study included 200 subjects, 100 with and 100 without DED symptoms defined by the Schein questionnaire, who underwent assessment of DED signs [visual acuity, PBBT, conjunctival hyperemia, lid-parallel conjunctival folds-LIPCOF, tear film break-up time-TBUT, fluorescein corneal staining, and meibum score]. Results: DED subjects had a lower PBBT than controls (p < 0.001), with subjective (6 (1-45) s vs. 8 (1-70) s) and objective (6 (2-33) s vs. 8 (2-50) s) PBBT measurements being similar between repeats. The correlations between subjective and objective PBBT measurements were significantly positive (R = 0.873, p < 0.001). Subjective PBBT was negatively related to the Schein questionnaire (R = -0.217, p = 0.002), conjunctival hyperemia (R = -0.105, p = 0.035), and corneal staining (R = -0.153, p = 0.031), while positively related to the TBUT (R = 0.382, p < 0.001) and meibum score (R = 0.106, p = 0.033). Logistic regression analysis showed DED symptoms were significantly associated with subjective PBBT (AOR 0.91, p = 0.001), TBUT (AOR 0.79, p < 0.001), meibum score (AOR 0.65, p = 0.008), LIPCOF (AOR 1.18, p = 0.002) and corneal staining (AOR 1.14, p = 0.028). Conclusions: Subjective self-reported PBBT is a reliable and non-invasive screening test for evaluating time-wise changes in visual acuity and detecting a tear film dysfunction.

The Influence of Tear Film Quality on Visual Function.

The prevalence of dry eye disease (DED) is increasing globally, resulting in a variety of eye symptoms characterized by discomfort and visual disturbances. The accurate diagnosis of the disease is often challenging and complex, requiring specialized diagnostic tools. This study aimed to investigate the impact of tear film instability on visual function and to evaluate the value of post-blink blur time (PBBT) as an alternative method for assessing tear film stability. The study included 62 subjects: 31 with subjective symptoms of DED (Group A) and a control group consisting of 31 healthy participants (Group B). Symptoms were assessed using the standard Schein questionnaire, supplemented with additional questions. PBBT was measured using standard Snellen charts to investigate a potential association between PBBT and tear film dysfunction. Additional clinical assessments included tear film break-up time (TBUT). Statistically significant differences were observed in the average values of PBBT and TBUT between the examined groups. The average PBBT was 8.95 ± 5.38 s in the group with DED and 14.66 ± 10.50 s in the control group, p < 0.001. Group A exhibited an average TBUT of 4.77 ± 2.37 s, while Group B had a TBUT of 7.63 ± 3.25 s, p < 0.001. Additionally, a strong positive correlation was identified between PBBT and TBUT values (r = 0.455; p < 0.001). The research confirms that tear film stability has an important role in the refraction of light and the maintenance of optical quality of vision. PBBT could potentially function as an objective and clinically significant screening test for DED.

Atmospheric pollutant black carbon induces ocular surface damage in mice

The threats of air pollution to human health have been gradually discovered, including its effects on eyes. The purpose of the study is to investigate the potential correlation between ocular surface exposure to black carbon and ocular surface structural damage as well as tear film dysfunction. To achieve this goal, 60 6-8-week-aged male BALB/C mice were randomly divided into 4 groups (n = 15). 0.5 mg/ml (group A), 1 mg/ml (group B), 5 mg/ml (group C) black carbon suspension droplets and PBS solution (group D) were used in the right eyes, 4 μl per time of three times per day. Tear break-up time, corneal fluorescein staining scores, and tear volume were assessed before treatment (day 0) and on days 4, 7, 10, and 14 after treatment. On day 14, the mice were sacrificed, and corneal and conjunctival tissues were collected for histological analysis. As the exposure time increased, there were no significant changes in the measured parameters from PBS-treated group of mice (P > 0.05). However, in the black carbon-treated group, there were significant decreases in tear film break-up time, significant increases in corneal fluorescein staining scores, and significant reductions in tear secretion (all P < 0.05). After 14 days, H&E staining of the corneal epithelium showed that in the PBS-treated group of mice, the corneal epithelial cells were neatly arranged, with no inflammatory cell infiltration, while in the black carbon-treated group, the corneal epithelium was significantly thickened, the basal cell arrangement was disrupted, the number of cell layers increased, and there was evidence of inflammatory cell infiltration. In the ultrastructure of the corneal epithelium, it could be observed that the black carbon-treated group had an increased amount of corneal epithelial cell detachment compared to the PBS-treated group, at the same time, the intercellular connections were looser, and there was a decrease in the number of microvilli and desmosomes in the black carbon-treated group. The results indicate that the ocular surface exposure to black carbon can result in a decrease in tear film stability and tear secretion in mice. Moreover, it can induce alterations in the corneal structure.

Dry eye in Parkinson's disease: a narrative review.

In Parkinson's disease (PD) patients, a wide range of ocular and visual disorders are present. Tear film instability, inflammation and dysfunction of the ocular surface, and the presence of symptoms of visual disturbance characterize dry eye, a multifactorial disease of the ocular surface. Based on a literature search, we discuss the frequency, pathogenesis, and influence on the quality of life of patients with dry eye in Parkinson's disease. Furthermore, we review the available means of diagnosis and management of dry eye. An improvement in awareness and recognition of dry eye is needed to provide suitable, personalized therapeutic options for PD patients, aiming to improve their quality of life, independence, and safety.

Tear film dysfunction after clear corneal phacoemulsification in diabetics and non-diabetics.

A prospective cohort study was conducted in a tertiary eye care centre to study the incidence of tear film dysfunction and its recovery in diabetics and non-diabetics after clear corneal phacoemulsification. A total of 50 diabetics and 50 non-diabetics underwent clear corneal phacoemuslfication. Schirmer's I test (SIT), tear film break-up time (TBUT), corneal staining, tear meniscus height (TMH), and ocular surface disease index (OSDI) assessment were done preoperatively, postoperatively at 7 days, 1 month, and 3 months in both groups to assess tear film function. Both groups showed decreased SIT and TBUT values on postoperative Day 7, after which they gradually improved. SIT and TBUT values in diabetics were significantly lower than that in non-diabetics postoperatively (P < 0.001). SIT in non-diabetics reached baseline levels at postoperative 3 months. OSDI scores reached peak levels in both groups on postoperative Day 7, but were higher in diabetics than non-diabetics (P < 0.001). OSDI scores gradually improved over 3 months but remained over baseline levels in both groups. Corneal staining was positive in 22% diabetics and 8% non-diabetics at postoperative Day 7. However, none of the patients had corneal staining at 3 months. Tear meniscus height (TMH) did not reveal any significant difference between the two groups at any time interval. We concluded that tear film dysfunction after clear corneal incision occurs in both groups, but is more severe and recovers more slowly in diabetics than non-diabetics.

Evaluation of changes in ocular surface disease index score and meibomian gland parameters in primary pterygium.

Pterygium is a commonly occurring ocular pathology, characterized by a benign proliferation of conjunctiva which extends onto the corneal surface. Abnormal tear film and meibomian gland (MG) dysfunction have been linked to pterygium development. This study was done to evaluate the changes taking place in the Ocular Surface Disease Index (OSDI) score and other tear film parameters with MG parameters in patients of primary pterygium as well as evaluation of the relation between them in pterygium. This was a case-control study, done in a tertiary care hospital in North India. Patients presenting to the ophthalmology outpatient department with a diagnosis of pterygium were enrolled in the pterygium study group along with their gender- and age-matched controls. Both groups were evaluated for OSDI score and other tear films and MG parameters were compared. The results were analyzed using SPSS version 24.0. A P < 0.05 was considered statistically significant. The OSDI score was significant among the study groups with a P = 0.006 and the MG parameters of MG expression score, lid margin abnormality, and meiboscore were also significant with a P = 0.002, 0.002, and < 0.01, respectively. There is a positive association between pterygium, tear film abnormality, and MG disease (MGD). A strong association was also established between MGD and dry eye. Any alteration in one will aggravate the other.

Variability of autonomic nerve activity in dry eye with decreased tear stability

The autonomic nervous system plays a crucial role in the maintenance of homeostasis. Neurogenic inflammation due to decreased stability of tear film may induce changes in autonomic nerve activity, which could be associated with symptom expression.This study aimed to measure biological parameters that represent autonomic nerve activity in dry eye (DE)s caused by tear film dysfunction and investigate their relationship with symptom intensity. This prospective, cross-sectional, comparative study evaluated 34 eyes of 34 participants (mean age: 52.5 ± 13.4 years; range: 20-81 years) without keratoconjunctival damage. Nineteen eyes in the DE group showed DE symptoms and tear break-up time (TBUT) of ≤5 seconds (short TBUT DE); the 15 eyes in the non-DE group showed no DE symptoms. Autonomic nerve activity was measured for 10 minutes-starting and ending 5 minutes before and after instilling ophthalmic solution-and evaluated using the low-frequency component (LF) to the high-frequency component (HF) ratio of heart rate variability (autonomic balance). The pre-ophthalmic solution administration LF/HF ratio was not significantly different (P = 0.59) between the two groups, however, the standard deviation of the LF/HF ratio (LF/HF-SD) tended to be higher in the DE group than that in the non-DE group (P = 0.086). The DE symptom intensity was significantly related to LF/HF-SD (P = 0.005), which significantly decreased after ophthalmic solution administration in the DE group (P = 0.04). The large fluctuations in autonomic balance may be key for the understanding of the mechanism underlying DE symptoms.

Immunobiologicals and ocular surface disease.

Immunobiologicals have surfaced to become a new cornerstone of treatment for a wide spectrum of inflammatory disorders with an immune basis. The targets have ranged from autoimmune conditions to transplantation, and now more into atopic inflammatory disorders with primary targets of asthma and atopic dermatitis. The clinical information garnered from these studies have provided an initial snapshot on the potential adverse effects of the immunobiologicals on the ocular surface as well as providing a potential opening of their use in the treatment of various chronic ocular surface and intraocular inflammatory disorders that have previously been relegated to limited therapeutic options primarily to the broad anti-inflammatory use of glucocorticosteroids. The use of immunobiologicals provides a more directed therapeutic approach to many of the ocular inflammatory disorders, as we continue to appreciate more of their underlying immunopathophysiology of ocular surface disorder,s including ocular allergy and tear film dysfunction.

Difference of Schirmer Test Results Before and After Using Smartphones with Various Screen Brightness Levels

Background : The use of smartphones and other digital devices such as laptops and tablets is familiar in Indonesian society. Excessive uses of the devices are associated with dry eye syndrome and tear film dysfunction. The intensity of blue light when penetrating the eye is believed to affect tear film stability. Thus it will encourage tear evaporation which proved by Schirmer test.Objective : To find out the difference of Schirmer test results before and after using a smartphone with various screen brightness levels.Methods : This study used pretest-posttest quasi-experimental study. The research subjects were students of the Faculty of Medicine, Diponegoro University (n = 30) who were selected by purposive sampling. In this study, the research subjects used smartphones for an hour with a predetermined screen brightness level, with the same room lighting. Before and after treatment the subject was measured the quantity of tears using the Schirmer test. Data were analyzed using the Wilcoxon test, Mann Whitney U test, and Kruskal Wallis test.Results : The average pretest result on low brightness was 25,60 ± 9,44 and the post-test result was 17,60 ± 8,45. The pre-test result on medium brightness was 27,90 ± 9,46 and the post-test result was 24,80 ± 10,46. The pre-test result on high brightness was 23,60 ± 6,80 and the post-test result was 19,10 ± 7,95. The Schirmer test results before and after using smartphones with low brightness showed a significant different (P&lt;0.05) and there was no significant difference for the pre-post test using smartphones with medium and high brightness. Comparison of Schirmer test results on low, medium and high screen brightness did not show a significant difference.Conclusion : There is no significant difference between the Schirmer test results among low, medium and high screen brightness after one hour of smartphone usage.

A study of meibomian gland and tear film changes in patients with pterygium in a tertiary care centre

To find out the correlation of Meibomian gland and Tear film dysfunction with pterygium. Institution based prospective cross sectional study. 70 (seventy) patients with unilateral primary progressive nasal Pterygium and 70 healthy adults without any ocular pathology were selected as comparison group from the Ophthalmology outpatient department of Calcutta National Medical College and hospital, Kolkata for a duration of 6 months from January 2020 to June 2020. Meibomian gland dysfunction was measured by meibomian gland expression score and lid margin abnormality score. Tear film changes were measured by Ocular Surface Disease Index (OSDI) Score , Tear break up time (TBUT), Tear meniscus height(TMH), Schirmer’s test 1 (ST1) and Corneal flourescein staining in both pterygium and control group and comparisons were done to find out the significance in differences. The Categorical variables were analyzed with the help of Pearson Chi square test, Spearman rho Correlation, Man Whitney U Test and the continuous variables were analyzed with the help of Independent T test and Pearson Correlation coefficient. The level of significance was considered as 95% of confidence interval i.e. P value &amp;#60;0.05. OSDI score, TBUT, meibomian gland expression score, lid margin abnormality score and corneal fluoresce in staining were significantly higher in pterygium group than others (p&amp;#60;0.05) whereas TMH values although showed differences between the two groups but were not statistically significant. ST1 were normal in pterygium group though had significant difference with control. Meibomian gland function was altered in patient with Pterygium which is also associated with uncomfortable ocular symptoms due to tear film abnormalities.

Comparative Evaluation of Tear Film Parameters Following Cataract Surgery in Diabetic Patients.

Purpose: To compare the propensity of manual small incision and phacoemulsification cataract surgery in causing tear film dysfunction and dry eye syndrome in diabetic patients. Methods: Diabetic patients in group A underwent manual small Incision Cataract surgery whereas in group B underwent phacoemulsification with similar post-operative regimes. The primary outcome measures were the Ocular Surface Disease Index (OSDI), a Subjective questionnaire. The secondary outcome measures were the Subjective Dry Eye (DE) questionnaire, Corneal Fluorescein staining, Tear meniscus height, Schirmer’s II test, and Tear film break-up time. All parameters were measured pre and then postoperatively. Result: 126 patients were divided into group A (undergoing small incision cataract surgery) and group B (undergoing phacoemulsification). The OSDI and subjective DE scores continued to be worse for Group A until the first month after which they became similar to group B with no statistically significant difference (p-value of 0.726 and 0.347 respectively). The OSDI and subjective DES at 3 months were better in both groups as compared to baseline (p &lt;0.0001). The objective tear film parameters (Schirmer’s, TBUT, TMH, and fluorescein staining scores) showed statistically significant changes from the baseline in both groups but the scores remained in the normal range clinically. Schirmer’s test scores were different between the two groups at three months (p=0.007) in SICS group being higher. Conclusion: Manual Small Incision Cataract Surgery (SICS) causes subjective dry eye symptoms more than phacoemulsification until 1 month of surgery in diabetic patients after which the subjective symptoms become similar to phacoemulsification at 3 months.

Dexamethasone-Loaded Nanostructured Lipid Carriers for the Treatment of Dry Eye Disease.

Dry eye disease (DED) or keratoconjunctivitis sicca is a chronic multifactorial disorder of the ocular surface caused by tear film dysfunction. Symptoms include dryness, irritation, discomfort and visual disturbance, and standard treatment includes the use of lubricants and topical steroids. Secondary inflammation plays a prominent role in the development and propagation of this debilitating condition. To address this we have investigated the pilot scale development of an innovative drug delivery system using a dexamethasone-encapsulated cholesterol-Labrafac™ lipophile nanostructured lipid carrier (NLC)-based ophthalmic formulation, which could be developed as an eye drop to treat DED and any associated acute exacerbations. After rapid screening of a range of laboratory scale pre-formulations, the chosen formulation was prepared at pilot scale with a particle size of 19.51 ± 0.5 nm, an encapsulation efficiency of 99.6 ± 0.5%, a PDI of 0.08, and an extended stability of 6 months at 4 °C. This potential ophthalmic formulation was observed to have high tolerability and internalization capacity for human corneal epithelial cells, with similar behavior demonstrated on ex vivo porcine cornea studies, suggesting suitable distribution on the ocular surface. Further, ELISA was used to study the impact of the pilot scale formulation on a range of inflammatory biomarkers. The most successful dexamethasone-loaded NLC showed a 5-fold reduction of TNF-α production over dexamethasone solution alone, with comparable results for MMP-9 and IL-6. The ease of formulation, scalability, performance and biomarker assays suggest that this NLC formulation could be a viable option for the topical treatment of DED.

Tear proteomic profile in three distinct ocular surface diseases: keratoconus, pterygium, and dry eye related to graft-versus-host disease

BackgroundDiseases of the anterior segment of the eye may present different mechanisms, intensity of symptoms, and impact on the patients’ quality of life and vision. The tear film is in direct contact with the ocular surface and cornea and can be easily accessed for sample collection, figuring as a promising source of potential biomarkers for diagnosis and treatment control. This study aimed to evaluate tear proteomic profile in 3 distinct ocular diseases: keratoconus (corneal ectasia), severe dry eye related to graft-versus-host-disease (tear film dysfunction and ocular inflammatory condition) and pterygium (conjunctival fibrovascular degenerative disease).MethodsTear samples were collected from patients of each condition and a control group. By using mass spectrometric analysis combined with statistics and bioinformatics tools, a detailed comparison of protein profile was performed.ResultsAfter Student’s t-test analyses comparing each condition to the control group, we found the following number of differentially expressed proteins: 7 in keratoconus group, 29 in pterygium group, and 79 in GVHD group. Following multivariate analyses, we also report potential candidates as biomarkers for each disease.ConclusionsWe demonstrated herein that mass spectrometry-based proteomics was able to indicate proteins that differentiate three distinct ocular conditions, which is a promising tool for the diagnosis of ocular diseases.

Allergic inflammation of the anterior surface of the eye.

Background: Ocular allergies affect an estimated 40% of the population, 98% of which are because of allergic conjunctivitis and includes tear film dysfunction. With the current advent of both repurposed drugs for ocular allergies, as well as novel drugs, lubricants and methods of administration, there is a need to update new treatments to optimize the care of ocular allergy patients. Methods: An overview of mediators, clinical characteristics and management is provided in a summary format. Results: Lubricants (best when refrigerated provide immediate relief that is short lived (several minutes) due to its dilutional effect on mediators and pollen in the tear film. Immediate and longer-term benefit occurs from different topical and oral medications - primarily histamine receptor agonists. Conclusion: The newest prescription topical ophthalmic histamine H1 receptor antagonist (an inverse agonist) to be approved by the U.S. Food and Drug Administration in the past 10 years (U.S. NDA approved May 30, 2017) is cetirizine ophthalmic solution for the treatment of ocular itching with allergic conjunctivitis in adults and in children more than 2 years old.

Tear film assessment in sudanese diabetic patients attending Jabir Abu Eliz Diabetic Center, Khartoum, Sudan

Background: Several local and systemic conditions predispose the eye to the development of dry eye disorders due to tear film dysfunction, which is presented in variable degrees of eye irritations and inflammation. Diabetes mellitus (DM) is among the most common risk factors of dry eye disease (DED). It is more common in older females than males. Tear film assessment can be tested with some simple tests such as Schirmer's test (ST), fluorescein strip (FS) (breakup time [BUT]) test, and lissamine green strip (LGS) test. Objective: The aim of this study is to assess the tear film dysfunction in diabetic patients with ST, FS papers, and LGS papers and compare their diagnostic values. Materials and Methods: In a cross-sectional hospital-based study, consecutive 126 diabetic patients were examined at Jabir Abu Eliz Diabetic Center in Khartoum for their tear film dysfunction. All selected patients had simultaneously undergone ST, FS (BUT) test, and LGS test in the same order and equal definite intervals in all patients over a 2-month period (September 1, 2013–November 1, 2013). Clinical and personal information was obtained by direct patients and chart review before complete ophthalmic examinations. Results: The mean age of the study group was 53 ± 12.1 years (30–78 years). Fifty-seven patients (45.2%) were female and 69 (54.8%) were male. In the age group, 11 (8.7%) patients were of type I DM, whereas 115 (91.3%) of type II DM. Forty-four (34.9%) patients had good DM control and 82 (65.1%) had poor DM control. The ST results of the current study demonstrated the presence of 142 patients (56.3%) in the “normal Schirmer's grade,” 49 patients (19.4%) in “mild-to-moderate Schirmer's grade,” and 61 patients (24.2%) in “severe Schirmer's grade.” In the BUT “FS” test, 165 patients (65.5%) gave normal results, whereas 87 patients (34.5%) showed severe tear dysfunction results, with a highly significant difference with P = 0.001. Whereas, in the LGS test, 201 patients (79.8%) were of “normal grade” results and 51 patients (20.2%) were “mild-to-moderate” grade. Conclusion: DED is an important feature of poorly controlled DM, which can be easily detected by performing a variety of simple quick tests such as the ST, fluorescein tear BUT test, and LGS test. There is notable variation among these three tears; therefore, a combination of any two tests is necessary. There is a strong correlation between qualities of the DM control, duration of DM, and severity of DED.