Schirmer Test Strips Research Articles

Tear Proteomics in Infants at Risk of Retinopathy of Prematurity: A Feasibility Study.

This feasibility study investigated the practicability of collecting and analyzing tear proteins from preterm infants at risk of retinopathy of prematurity (ROP). We sought to identify any tear proteins which might be implicated in the pathophysiology of ROP as well as prognostic markers. Schirmer's test was used to obtain tear samples from premature babies, scheduled for ROP screening, after parental informed consent. Mass spectrometry was used for proteomic analysis. Samples were collected from 12 infants, which were all adequate for protein analysis. Gestational age ranged from 25 + 6 to 31 + 1 weeks. Postnatal age at sampling ranged from 19 to 66 days. One infant developed self-limiting ROP. Seven hundred one proteins were identified; 261 proteins identified in the majority of tear samples, including several common tear proteins, were used for analyses. Increased risk of ROP as determined by the postnatal growth ROP (G-ROP) criteria was associated with an increase in lactate dehydrogenase B chain in tears. Older infants demonstrated increased concentration of immunoglobulin complexes within their tear samples and two sets of twins in the cohort showed exceptionally similar proteomes, supporting validity of the analysis. Tear sampling by Schirmer test strips and subsequent proteomic analysis by mass spectrometry in preterm infants is feasible. A larger study is required to investigate the potential use of tear proteomics in identification of ROP. Tear sampling and subsequent mass spectrometry in preterm infants is feasible. Investigation of the premature tear proteome may increase our understanding of retinal development and provide noninvasive biomarkers for identification of treatment-warranted ROP.

Prevalence, Patterns, and Predictors of SARS-CoV-2 RNA and Culturable Virus in Tears of a Case-Ascertained Household Cohort

To investigate the prevalence, patterns, and predictors of SARS-CoV-2 RNA and culturable virus in tears of a case-ascertained household cohort. Prospective, longitudinal case-ascertained household cohort identified through convenience sampling. This analysis was restricted to individuals who were non-hospitalized, symptomatic, and tested positive for SARS-CoV-2 by nasal RT-PCR. Tears and anterior nasal biospecimens were serially collected throughout the acute period. Tears specimens were collected by the study staff using Schirmer test strips, and nasal specimens were self-collected. For both, SARS-CoV-2 RNA was quantified using qRT-PCR, and culturable virus was detected using presence of cytopathic effect (CPE) in tissue culture; positive CPE was confirmed by a qRT-PCR step. A series of cross-sectional unadjusted analyses were performed investigating the relationship between different sociodemographic determinants and biological factors associated with tears RNA positivity. Among the 83 SARS-CoV-2 infected participants, 10 (12%) had at least one RNA-positive tears specimen. Amongst these 10, 5 (50%) had concurrent presence of culturable virus, at a median of 7 days postsymptom onset (IQR: 4-7 days) (absolute range: 4-8 days). In this longitudinal cohort, we found evidence of culturable virus in the tears of a small proportion of nonhospitalized SARS-CoV-2 infected individuals. Current public health infection precautions do not account for transmission via tears, so these findings may improve our understanding of potential sources of SARS-CoV-2 transmission and contribute to developing future guidelines.

Heritability of tear fluid cytokines in healthy twins

PurposeOcular surface disease is common and it is associated with elevated concentration levels of cytokines in tear fluid. Studies of the normal variation in tear fluid inflammatory markers are lacking. New knowledge may help guide research into ocular surface disease biomarkers and therapeutics. MethodsIn this prospective twin cohort study, healthy individuals were recruited from a population-based registry. Tear fluid was collected with the Schirmer test strips was submerged in phosphate buffered saline and stored at −80° before undergoing 27-cytokine multiplex immunoassay analysis. Broad-sense heritability (h2) of cytokine concentrations was analyzed. Results90 participants (23 monozygotic and 22 dizygotic twin pairs) were included. Data availability allowed for heritability analysis of 15 cytokines, and a h2 >50% was seen for 10 cytokines. A statistical power of >80% was achieved for heritability analyses of the cytokines interferon gamma induced protein 10 (h2 = 94.8%), eotaxin (89.8%), interleukin 7 (86.6%), interleukin 1β (82.2%) and monocyte chemoattractant protein 1 (68.2%). ConclusionsThe tear fluid concentration of several analyzed cytokines was found to be highly heritable. A considerable amount of the inter-individual variation observed for the concentration of certain tear fluid cytokines can be linked to hereditary factors that cannot easily be modified by changing factors in the environment of patients. This suggests that a higher success in ocular surface disease drug discovery may be anticipated for drugs that have targets in specific populations, and points to the importance of emphasizing known preventive measures of ocular surface disease and examinations of close relatives of patients with ocular surface disease, such as dry eye disease.

Tear biomarkers.

An extensive exploration of lacrimal fluid molecular biomarkers in understanding and diagnosing a spectrum of ocular and systemic diseases is presented. The chapter provides an overview of lacrimal fluid composition, elucidating the roles of proteins, lipids, metabolites, and nucleic acids within the tear film. Pooled versus single-tear analysis is discussed to underline the benefits and challenges associated with both approaches, offering insights into optimal strategies for tear sample analysis. Subsequently, an in-depth analysis of tear collection methods is presented, with a focus on Schirmer's test strips and microcapillary tubes methods. Alternative tear collection techniques are also explored, shedding light on their applicability and advantages. Variability factors, including age, sex, and diurnal fluctuations, are examined in the context of their impact on tear biomarker analysis. The main body of the chapter is dedicated to discussing specific biomarkers associated with ocular discomfort and a wide array of ocular diseases. From dry eye disease and thyroid-associated ophthalmopathy to keratoconus, age-related macular degeneration, diabetic retinopathy, and glaucoma, the intricate relationship between molecular biomarkers and these conditions is thoroughly dissected. Expanding beyond ocular pathologies, the chapter explores the applicability of tear biomarkers in diagnosing systemic diseases such as multiple sclerosis, amyotrophic lateral sclerosis, Alzheimer's disease, Parkinson's disease, and cancer. This broader perspective underscores the potential of lacrimal fluid analysis in offering non-invasive diagnostic tools for conditions with far-reaching implications.

Tear Samples for Protein Extraction: Comparative Analysis of Schirmer's Test Strip and Microcapillary Tube Methods.

Tear sampling is an attractive option for collecting biological samples in ophthalmology clinics, as it offers a non-invasive alternative to other invasive techniques. However, there are many tear sampling methods still in consideration. This study explores the suitability of Schirmer's test strip and microcapillary tube as reliable and satisfactory methods for tear sampling. Tear samples were collected from eight healthy volunteers using the standard Schirmer's test strip method with or without anesthesia and microcapillary tubes. The total tear protein concentrations were analyzed via spectrophotometry and bicinchoninic acid (BCA) protein assay. The protein profile was determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal wetting length of Schirmer's strip and suitable buffer solutions were compared. Discomfort levels reported by participants and the ease of execution for ophthalmologists were also evaluated. Tear samples exhibited typical protein profiles as shown by SDS-PAGE.The mean total protein obtained from an optimum wetting length of 20 mm using Schirmer's strip without anesthesia in phosphate-buffered saline (PBS) yielded substantial quantities of protein as measured by nanophotometer (220.20 ± 67.43 µg) and the BCA protein assay (210.34 ± 59.46 µg). This method collected a significantly higher quantity of protein compared to the microcapillary tube method (p=0.004) which was much more difficult to standardize. The clinician found it harder to utilize microcapillary tubes, while participants experienced higher insecurity and less discomfort with the microcapillary tube method.PBS used during the tear protein extraction process eluted higher tear protein concentration than ammonium bicarbonate, although the difference was not statistically significant. Using anaesthesia did not ease the sampling procedure substantially and protein quantity was maintained. Good quality and quantity of protein from tear samples were extracted with the optimized procedure. Schirmer's strip test in the absence of local anesthesia provided a standard, convenient, and non-invasive method for tear collection.

Reduced tear fluid production in neurological diseases: a cohort study in 708 patients

BackgroundTear fluid (TF) production is an important component of normal ocular function. It is regulated by parasympathetic and sympathetic innervation. Because parasympathetic nerve fibers originate in the brainstem, pathology in this brain region may affect TF production. For example, a reduction in TF production has been described in patients with Parkinson’s disease (PD).MethodsTF was collected at one center from 772 individuals, 708 of which were patients with different neurological diseases, and 64 healthy controls. Wetting lengths (WL) were recorded using Schirmer test strips with a collection time of 10 min.ResultsWL correlated negatively with age and was significantly reduced in subgroups of patients with neurodegenerative diseases (NDDs) (PD, Amyotrophic lateral sclerosis (ALS), other motor neuron diseases (MNDs)), as well as inflammatory/autoimmune/infectious central nervous system (CNS) diseases and vascular CNS diseases (VCDs), even if corrected for age or sex. While temperature had a significant negative effect on TF production, other environmental factors, such as hours of sunlight and humidity, did not.ConclusionWL was altered in many neurological diseases compared to healthy controls. Most importantly, we observed a reduction of WL in NDDs, independent of age or sex. This study highlights the potential of WL as an easily obtainable parameter and suggests functional alterations in the autonomic innervation in various neurological disorders.

Evaluating Moisture Migration in Schirmer Test Strips: Exploring Brand-Specific Variations and Introducing Calibration and Conversion Methods.

Schirmer test results are widely used for ocular surface disease assessment, but Schirmer strips are not standardized. We compare the characteristics and tear volume with millimeter moisture migration in different brands of Schirmer strips and introduce methods for volume-based, brand-independent calibration. Physical parameters of Haag-Streit, EagleVision, TearFlo, Contacare, and MIPL/A6 Schirmer strip brands were compared. Schirmer strip millimeter moisture migration distances were assessed 5 minutes after application of incremental microliter volumes of human tears. Linear regression analysis of data points from each Schirmer strip brand was performed, and the root-mean-square deviation of data points to the best-fit linear regression was calculated. Calibration correction was performed by converting migration distance to the corresponding tear volume. A reference table and calibration method formulas were created. Schirmer strips differed in design, shape, and manufacturing precision. Strip width, weight, and length were different between the 5 brands ( P < 0.05). A wide range of Schirmer strip moisture migration values for identical tear volumes was observed among brands. Statistical measurement resulted in a root-mean-square deviation of 2.9 mm for all data points from all brands. Millimeter to volume and weight to volume-based calibration correction methods resulted in a 2.2- and 3.1-fold measurement error reduction, respectively. Our findings highlight the lack of standardization among different brands of Schirmer strips, raising concerns about potential sources of unintentional measurement errors. We propose volume-based Schirmer strip calibration methods and conversion of millimeter to microliter results to achieve brand-independent results and improve Schirmer test accuracy.

Investigation of Inter- and Intra-Day Variability of Tear Fluid Regarding Flow Rate, Protein Concentration as well as Protein Composition.

The purpose of this study was to present the determination of inter- and intra-day variations in tear flow rate, and tear fluid protein concentration, as well as protein composition regarding their impact for future biomarker studies. Tear fluid was collected noninvasively from 18 healthy subjects by performing Schirmer tests at 4 different time points repetitive in a period of 2days. The tear flow rate on the Schirmer test strips was measured. Proteins were extracted from strips and quantified using amino acid analysis. Protein composition was analyzed by the strips data-independent (DIA) based mass spectrometry. To exclude any impairments to health, volunteers underwent a detailed neurological as well as an ophthalmological examination. Whether tear fluid was collected from oculus sinister or oculus dexter did not affect the tear flow rate (P ≈ 0.63) or protein concentration (P ≈ 0.97) of individual subjects. Moreover, protein concentration was independent from the tear volume, so that a change in volume may only influence the total protein amount. When the examination days were compared, investigation of tear flow rate (P ≈ 0.001) and protein concentration (P ≈ 0.0003) indicated significant differences. Further, mass spectrometric analysis of tear fluid revealed 11 differentially regulated proteins when comparing both examination days. Our findings provide evidence of inter-day variation in tear flow rate, tear proteome concentration, and composition in healthy subjects, suggesting that inter-day variation needs to be taken into consideration in biomarker research of tear fluid. Identified proteins were assigned to functions in the immune response, oxidative and reducing processes, as well as mannose metabolism.

Correlation of Blood Glucose Level and Tear Production Among Young Adult Women

Blood glucose monitoring is a way of testing the concentration of glucose in the blood. Tears are clear, salty, slightly alkaline and watery substance which helps in seeing clearly and maintaining the health of the eyes. This study was carried out to determine the correlation of blood glucose level and tear production among young adult women. A total of 108 subjects were part of this study. The Accu Chek glucometer was used to measure the blood glucose level and the Schirmer test strips were used to measure the tear production of the subjects. Results showed that the mean FBG level was 98.86±12.21; the mean RBG was 114±39.39, and the mean tear production was 18.37±11.63. SPSS version 23 data analysis using the Pearson Product Moment Correlation Coefficient at 0.05 level of significance and 95% confidence interval revealed that there were no significant correlations of both fasting and random blood glucose levels (P˃0.05) with tear production among young adult women. It was therefore concluded from the study that there was no correlation between blood glucose level and tear production among adult women. Further research in a wider geographical area was recommended. Keywords: Fasting Blood Glucose, Random Blood Glucose, Tear production, Schirmer Test, Dry Eye Syndrome, Diabetes Mellitus

Maximal tear secretion evoked by controlled stimulation of corneal sensory nerves in healthy individuals and dry eye subjects.

To measure, the tear flow changes evoked in healthy subjects and dry eye disease (DED) patients by controlled sensory stimulation of the eye surface with i-Onion™, a new stimulation device. Sensory corneal nerves were stimulated with an instrument (i-Onion™) that ejects puffs of CO2 gas (99.9%) at 200 ml.min-1 for 3s, delivered 5 mm from the cornea. Using Schirmer test strips, tear volumes were measured over 3 min in the cornea of one eye before (basal tear volume -BTV) and in the other eye after stimulation of the sensory nerves with CO2 (stimulated tear volume -STV). These measurements were obtained from a control group of adults of either sex (17 students aged 20-30 and 29 subjects without signs of dry eye aged 25-61), a cohort of DED patients (aged 34-75) that included 12 asymptomatic, suspected DED subjects (Schirmer <7 mm and/or TBUT <10s), and 30 Sjögren's syndrome (SS) patients. CO2 stimulation significantly increased the tear volume (BTV = 14.6 ± 1.0 mm, STV = 19.0 ± 1.1 mm: n = 46) in 78% of control subjects, reflecting a mean tear reserve volume (TRV = STV-BTV) of 4.4 ± 0.8 mm. Individual differences were wide, and while no increase in reflex tearing was evoked in 30% of subjects with a BTV >10 mm, the remaining 70% responded vigorously to stimulation, even those with a BTV >18 mm. Asymptomatic DED subjects displayed weaker responses to CO2 stimulation, with lower STVs. Both the BTV and STV of SS patients were low, significantly below those of the healthy controls. Measuring the rise in reflex tearing volume evoked by controlled corneal stimulation provides objective information about the tear glands' secretory capacity in health and disease.

ITEARS: a novel platform for using tears as potential disease biomarkers.

Dear Editor, Exosomes are double-membrane lipid bilayer nanoparticles secreted into extracellular spaces by various cells of the body1. They can be found in several body fluids such as serum, breast milk, saliva, cerebrospinal fluid, semen, and urine in both physiological and pathological conditions2. They have been indicated to have diagnostic applications in terms of both their morphology and miRNA expression. Exosome extraction and assessment are made efficient by the identification of various transport proteins, CD9, CD81, and heat shock protein, all of which are an integral part of exosome composition3. Around 4400 distinct proteins have been identified in exosomes using mass spectrophotometry4. Much research is being conducted, which focuses on the employment of these vesicles as innovative biomarkers for diagnosis, prognosis, and management of cancer and other diseases2. In comparison with other biofluids, tears, because of their less protein and debris content as compared to blood and its noninvasive collection, are the most appropriate source for exosome isolation. Their easy accessibility for biomarker analysis using the Schirmer test strip greatly boasts its importance5. To gain access to the gateway of a multitude of diseases in a drop of tear, successful approaches have been adopted to isolate tear components such as glucose, lactoferrin, lysozyme, and alcohol, for depicting the pathological states including dry eye symptoms, infections, diabetes, cardiovascular disease, endothelial dysfunction, coagulopathies, and polycystic ovary syndrome6. They have also been applied in testing breast cancer further suggesting the noninvasive diagnostic potential of tear exosomes7. However, due to practical constraints in the isolation and handling of tear exosomes, despite their attractive potential, limited progress has been made in intensely acknowledging the clinical value of tear exosomes. Isolation is usually done on the principles relying on the size and particle density of exosomes. Tear exosomes isolation is commonly achieved by ultracentrifugation and size exclusion chromatography8. Ultracentrifugations’ efficiency is limited by its long processing time, large sample requirement, and low recovery while size exclusion chromatography lacks a proficient enrichment facility thus hampering the use of tear exosomes as diagnostic tools and discouraging further studies. Since the volume of tears samples collected from patients is usually scarce and the extraction procedure is complex, novel procedures are needed to be developed for paving new dimensions of disease deciphering by using tear as a sample. Recently a team of researchers developed an incorporated tear-exosome analysis via a rapid-isolation system (iTEARS) platform to better comprehend exosome study and enhance exosome extraction9. iTEARS is a microstructure-based device containing a dual nanoporous membrane installed in a reservoir with two outlets operating on basis of a negative-pressure-oscillation strategy and on-device immunodetection. To ensure fast exosome isolation, alternate negative pressure switching is applied on both sides, and in this way, large particle exosomes get captured while small fragments (eg, proteins, sugars) are separated. This experiment exhibits that exosome can be enriched positively in under 5 minutes. The separated exosomes can then be utilized for different diagnostic analyses like PCR, sequencing, and proteomics. For practical utility of iTEARS, laboratory analysis of these exosomes was performed to distinguish a healthy control from Diabetes Mellitus and Diabetic Retinopathy. It was also used to identify different dry eye diseases thus emphasizing the important role of iTEARS and a hope for it discovering various other clinical conditions and their molecular diagnosis. In the field of medicine, there is an ever occurring need to explore and identify new techniques for the diagnosis of disease and progression of pathology. Studies around human tear analysis have shown the potential to be a reliable and efficient method to present biomarkers for various pathological conditions of the human body. iTEARS technique not only produces results but is cost-effective and time friendly as well. Mega-scale clinical trials are needed to verify its potential for the diagnosis of disease. Tear sampling via iTEARS is feasible, noninvasive, easy to conduct, and effective. Ethical approval Not applicable. Sources of funding None. Author's contribution All authors equally contributed. Conflicts of interest disclosure The authors declare that they have no financial conflict of interest with regard to the content of this report. Research registration Unique Identifying number (UIN) None. Guarantor Syeda Shahnoor.

IgA-Based Secretory Response in Tears of COVID-19 Patients: A Potential Biomarker of Pro-Inflammatory State in Course of SARS-CoV-2 Infection.

Mucosal immunity, including secretory IgA (sIgA), plays an important role in the early defence against SARS-CoV-2 infection. However, a comprehensive evaluation of the local immune response in tears in relation to blood antibody reservoirs has not yet been conducted. A total of 179 symptomatic laboratory-confirmed COVID-19 patients were included in this single-centre study. Conjunctival swabs were analysed by a reverse transcription polymerase chain reaction for the detection of SARS-CoV-2 RNA. In parallel, tear samples collected by Schirmer test strips and plasma samples were analysed by ELISA to detect anti-S1 IgA levels. The concentrations of selected inflammatory cytokines in tears were determined by a magnetic bead assay. Anti-SARS-CoV-2 sIgA was present in the tears of 81 (45.25%) confirmed COVID-19 patients, and the tear IgA levels were correlated with the plasma IgA levels (Rs = +0.29, p = 0.0003). SARS-CoV-2 RNA in the conjunctival sac was identified in 18 COVID-19 patients (10%). Positive correlations between the tear IgA level and the concentrations of several cytokines TNF-α (Rs = +0.23, p = 0.002), IL-1β (Rs = +0.25, p < 0.001), IL-2 (Rs = +0.20, p = 0.007), IL-4 (Rs = +0.16, p = 0.04), IL-5 (Rs = +0.36, p < 0.001), IL-6 (Rs = +0.32, p < 0.001), IL-8 (Rs = +0.31, p < 0.001), VEGF (Rs = +0.25, p < 0.001) and GM-CSF (Rs = +0.27, p < 0.001) were also found. Quantitative tear film-based sIgA could potentially serve as a rapid and easily accessible biomarker of external mucosal immunity to SARS-CoV-2. The concentration of sIgA is directly related to individual host immune responses to SARS-CoV-2 infection.

Putative Biomarkers in Tears for Diabetic Retinopathy Diagnosis.

PurposeTear fluid biomarkers may offer a non-invasive strategy for detecting diabetic patients with increased risk of developing diabetic retinopathy (DR) or increased disease progression, thus helping both improving diagnostic accuracy and understanding the pathophysiology of the disease. Here, we assessed the tear fluid of nondiabetic individuals, diabetic patients with no DR, and diabetic patients with nonproliferative DR (NPDR) or with proliferative DR (PDR) to find putative biomarkers for the diagnosis and staging of DR.MethodsTear fluid samples were collected using Schirmer test strips from a cohort with 12 controls and 54 Type 2 Diabetes (T2D) patients, and then analyzed using mass spectrometry (MS)-based shotgun proteomics and bead-based multiplex assay. Tear fluid-derived small extracellular vesicles (EVs) were analyzed by transmission electron microscopy, Western Blotting, and nano tracking.ResultsProteomics analysis revealed that among the 682 reliably quantified proteins in tear fluid, 42 and 26 were differentially expressed in NPDR and PDR, respectively, comparing to the control group. Data are available via ProteomeXchange with identifier PXD033101. By multicomparison analyses, we also found significant changes in 32 proteins. Gene ontology (GO) annotations showed that most of these proteins are associated with oxidative stress and small EVs. Indeed, we also found that tear fluid is particularly enriched in small EVs. T2D patients with NPDR have higher IL-2/-5/-18, TNF, MMP-2/-3/-9 concentrations than the controls. In the PDR group, IL-5/-18 and MMP-3/-9 concentrations were significantly higher, whereas IL-13 was lower, compared to the controls.ConclusionsOverall, the results show alterations in tear fluid proteins profile in diabetic patients with retinopathy. Promising candidate biomarkers identified need to be validated in a large sample cohort.

SARS-COV-2 viral load in tears of patients with COVID-19 in the early symptomatic stages: comparison of two different tear sampling methods.

PurposeTo evaluate the presence of SARS-CoV-2 virus in tears of patients with COVID-19 in the early symptomatic stages and to compare two different sampling methods.Materials and methodIn this cross-sectional study, tears sampling was performed in COVID-19 patients admitted within the first 7 days of symptom onset. The samples were collected with both conjunctival swabs and Schirmer strips. Each specimen was analyzed via RT-PCR. The viral load was evaluated in terms of the cycle threshold value. Ocular and systemic symptoms and comorbidities of the patients were also recorded.ResultsForty patients were included. The average time from the initiation of symptoms was 3.15 days. Unilateral conjunctivitis has been observed in 5% of patients and foreign body sensation in 7.5% of patients. No viral RNA was detected in the tear samples of the patients with ocular findings. The positivity rate for SARS-CoV-2 in tears was 2.5% (n = 1). None of the samples collected by Schirmer test strips yielded positive polymerase chain reaction result for SARS-COV-2. The Ct value of the positive conjunctival swab was 36.03 and the nasopharyngeal Ct value of the same patient was 25.68.ConclusionThe SARS-CoV-2 viral shedding rate has been determined as 2.5% in the tears of early symptomatic stage COVID-19 patients. The viral load of the tears was lower than the naso-oropharynx. The conjunctival swab method is recommended in tear collection to evaluate the presence of SARS-CoV-2 by RT-PCR analysis in low viral load tears.

Comparison of Dry eye in pre and post menopause

The aspire of the study was to perceive the frequency of dry eyes in pre and post menopause. Methods: Women of age 45 to 70 were involved. Schirmer test was performed, the normal production level was considered over 10mm.The level under 10mm was categorized as moderate and &lt;5mm was severe. It was a comparative cross-sectional study that was performed between January 2010 and May 2016.The study was performed at University of Lahore Teaching Hospital. The study included a total 326 female patients comprised of 126 premenopausal and 126 postmenopausal. The women aged between 40 to 70 years were agreed to participate .There is a questionnaire containing the questions about status of menopause i.e pre and post and symptoms of dry eyes were used. Schirmer test 2 was performed and dry eye was evaluated on the basis of scoring of dry eyes symptoms. Schirmer test with anesthesia was performed. In this study alkane drops were used and the whole procedure was well explained to the patient before performing. Schirmer test readings were noted in questionnaire as OD and OS and the symptoms of dry eyes like itching, watering, redness, burning sensation were noted as yes and no. Schirmer test strips were used with reading from 0 to 35mm.Patients with corneal disease or ulcer or having any such disease that can disturb the tear film and cause dry eye was excluded. Moreover the pregnant women, smokers, diabetic, thyroid disorders or patients with systemic disease were not included in the study. It is performed in such a way that the in a confined room the patient was seated comfortably with fan off. Alkane drops were applied to the eye. The test was performed on both eyes at the same time and standardized schirmer strips were inserted into conjunctival sac of lateral part of lower eyelid. The strips were removed after 5 minutes .We kept the standard that was:&#x0D; Abnormal if &lt;10mm/5min&#x0D; Moderate if 10-15mm/5min&#x0D; Normal if &gt;5mm/5min&#x0D; Results:&#x0D; In our study 87.8% among premenopausal were mild,11.6% moderate and 0.6% severe. Among postmenopausal 7.4% were mild,43.8%moderate and 48.8% severe. It was discovered that out of 164 premenopausal women 71.3% were facing watering and out of 162 postmenopausal women, 46.9% were facing watering. Among 164 premenopausal 72.6% were having eye redness and out of 162 postmenopausal 46.9%. Among 164 premenopausal 15.9% were facing difficulty in wearing contact lens and among postmenopausal were 48.1%.Prevelance of participants facing difficulty in night time driving among 164 premenopausal women was 10.4% and among postmenopausal was 33.3%.Among 164 premenopausal women 70.1% had dryness in areas like mouth, nose and vagina and among postmenopausal 92.0%. Hot flashes among 164 premenopausal women was 73.8% and among postmenopausal women 82.1%.Among 164 premenopausal women 97.6% were facing mood swings and among 162 postmenopausal women was 96.3%. The participants suffering from sleeplessness among premenopausal women was 81.1% and among postmenopausal women was 92.0%. Conclusion: It was discovered that the dry eye is more customary in postmenopausal women. The Schirmer test showed that dry eye is more prevalent in postmenopausal women.

A COMPARATIVE STUDY ON TEARING PATTERN OF PRETERM AND TERM NEONATES IN A TERTIARY CARE CENTRE AT EASTERN INDIA

Background: The preterm and term neonates secret basal and reex tear. The tear deciency can cause various ocular and systemic effects of drugs, used topically. If there is any reduced reex and basal tear secretion then it may mask the diagnosis of nasolacrimal duct obstruction. Aims And Objectives: To evaluate basal and reex tear production in preterm (post-conceptional age &lt;37 weeks) and term (post conceptional age ≥37 weeks) neonates. Methods: 60 preterm and 60 term neonates were examined. Tear secretion was evaluated by applying Schirmer test strips at inferior fornix for 5 minutes before (reex plus basal secretion) and after (basal secretion) applying topical anesthetic agent. Results: Mean (± SD) basal tear secretion was 5.76 (±1.44) mm in preterm and 7.73 (±1.87) mm in term neonates. Mean (± SD) reex tear secretion was 7.01 (±1.34) mm in preterm and 12.45 (± 2.28) mm in term neonates. Conclusions: Preterm neonates have reduced reex and basal tear secretion than term neonates. In term neonates tear production is similar to that in adults.

Development of a HPLC-MS/MS method for assessment of thiol redox status in human tear fluids

Oxidative stress is reported to be part of the pathology of many ocular diseases. For the diagnosis of ocular diseases, tear fluid has unique advantages. Although numerous analytical methods exist for the measurement of different types of biomolecules in tear fluid, few have been reported for comprehensive understanding of oxidative stress-related thiol redox signaling. In this study, a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed to determine a panel of twelve metabolites that systematically covered several thiol metabolic pathways. With optimization of MS/MS parameters and HPLC mobile phases, this method was sensitive (LOQ as low as 0.01 ng/ml), accurate (80–125% spike recovery) and precise (<10% RSD). This LC-MS/MS method combined with a simple tear fluid collection with Schirmer test strip followed by ultrafiltration allowed the high-throughput analysis for efficient determination of metabolites associated with thiol redox signaling in human tear fluids. The method was then applied to a small cohort of tear fluids obtained from healthy individuals. The method presented here provides a new technique to facilitate future work aiming to determine the complex thiol redox signaling in tear fluids for accurate assessment and diagnosis of ocular diseases.

SARS-CoV-2 RNA and antibodies in tear fluid

Background/aimsSARS-CoV-2 is highly contagious. More evidence concerning extrapulmonary transmission routes such as the eyes is urgently needed. Although the humoral immune response is important in the viral containment, the local...

Tear protein analysis in patients with primary acquired nasolacrimal duct obstruction treated with lacrimal passage intubation.

The pathophysiology of nasolacrimal duct obstruction (NLDO) may involve quantitative as well as qualitative changes in tears. We measured tear protein concentrations in patients with primary acquired NLDO and compared them with the tear proteins in healthy individuals and patients with dry eye disease. Case-control study. Twenty-four patients diagnosed with primary acquired NLDO who underwent endoscopic lacrimal passage intubation were included in the study. Tear fluid was collected with Schirmer's test strips three times: before intubation, after intubation while the nasolacrimal tube was in place, and after extubation. At the same time, 24 age-matched normal controls and 24 patients with dry eye were selected from subjects whose tears were collected during the same study period. We measured the following components of tear fluid: total protein, lactoferrin, albumin, and interleukin 6 (IL-6) levels. Total proteins and albumin levels in tears of the NLDO group were significantly lower than those of the control group (P < 0.001 and P = 0.014, respectively, Mann-Whitney U test). Total proteins, albumin, and lactoferrin levels were significantly increased after extubation of nasolacrimal tube (P < 0.001, P = 0.004, and P = 0.029, respectively, Wilcoxon matched-pairs signed-rank test). There were no statistically significant differences in total protein, albumin, lactoferrin and IL-6 levels between patients with NLDO after lacrimal passage extubation and controls. Our study shows distinct differences in protein composition of tear fluid in NLDO eyes and demonstrates that these can be normalized by nasolacrimal tube placement.

Predictive biomarkers for the progression of ocular complications in chronic Stevens-Johnson syndrome and toxic Eeidermal necrolysis

This study aimed to clarify predictive biomarkers of mild and severe ocular complications of Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) by examining the cytokines in tears. In 121 chronic-phase SJS/TEN eyes, cytokines in tear samples collected using Schirmer test strips were measured, and ocular sequelae severity was evaluated using an Ocular Surface Grading Score (OSGS) involving 7 components (conjunctivalization, neovascularization, opacification, keratinization, symblepharon, and upper/lower conjunctival-sac shortening), with findings categorized into grades 0–3 (maximum total OSGS: 21). Changes in cytokines between the mild and severe groups (mild: total OSGS of 10 or less, severe: total OSGS of 11 or more), and changes between SJS/TEN cases with and without each of the 7 components, were compared. In the severe group, there was significant upregulation of interleukin (IL)-8 (P < 0.01) and Granzyme B (GrzB) (P < 0.05). IL-8 was significantly upregulated in eyes with conjunctivalization, neovascularization, or opacification, GrzB was upregulated in eyes with keratinization, interferon-γ-inducible protein 10 (IP-10) was downregulated in eyes with conjunctivalization or neovascularization, and IL-1α was upregulated in eyes with opacification (all: P < 0.05). IL-8 and IP-10 was involved in conjunctivalization and neovascularization, while GrzB was involved in keratinization. IL-8 and GrzB in tears may reflect SJS/TEN-related ocular sequelae severity.