Diseases associated with ocular surface abnormalities: the importance of reflex tearing

Efficacy and Safety of Plasma Rich in Growth Factor in Patients with Congenital Aniridia and Dry Eye Disease

Congenital aniridia is a rare bilateral ocular malformation characterized by the partial or complete absence of the iris and is frequently associated with various anomalies, including keratopathy, cataract, glaucoma, and foveal and optic nerve hypoplasia. Additionally, nearly 50% of individuals with congenital aniridia experience symptoms of ocular dryness. Traditional treatment encompasses artificial tears and autologous serum. This study aimed to assess the effectiveness and safety of using platelet rich in growth factors (PRGF) plasma in patients with congenital aniridia and ocular dryness symptoms.

METHODS

The included patients underwent two cycles of a 3-month PRGF treatment. At 6 months, symptomatology was evaluated using the OSDI and SANDE questionnaires, and ocular surface parameters were analyzed.

RESULTS

The OSDI and SANDE values for frequency and severity demonstrated statistically significant improvements (p < 0.05). Ocular redness, corneal damage (corneal staining), and tear volume (Schirmer test) also exhibited statistically significant improvements (p < 0.05). No significant changes were observed in visual acuity or in the grade of meibomian gland loss.

CONCLUSION

The use of PRGF in patients with congenital aniridia and ocular dryness symptoms led to significant improvements in symptomatology, ocular redness, and ocular damage. No adverse effects were observed during the use of PRGF.

How Can We Best Diagnose Severity Levels of Dry Eye Disease: Current Perspectives

Dry eye disease (DED) is a common ocular condition, but the diagnosis relative to other ocular conditions and the evaluation of severity of the condition has often been difficult. This challenge can be due to clinical signs and symptoms not always correlating with each other. An understanding of the various components which create the condition, as well as the diagnostic measures used to evaluate these components, is useful to the clinician working with DED patients. This review paper will discuss traditional diagnostic options, diagnostic imaging, and Advanced Point of Care testing capabilities to determine the severity level of dry eye disease more adequately.

Impact of Plasma Rich in Growth Factors (PRGF) Eye Drops on Ocular Redness and Symptomatology in Patients with Dry Eye Disease

Background and Objectives: Dry eye disease (DED) is a common and very symptomatic pathology that affects normal daily activity. The aim of the study was to evaluate the efficacy of plasma rich in growth factors (PRGF) added to one routine treatment protocol for DED (artificial tears substitutes, lid hygiene, and anti-inflammatory therapy). Materials and Methods: Patients were divided into two groups of treatment: standard treatment group (n = 43 eyes) and PRGF group (n = 59). Patients' symptomatology (inferred from OSDI and SANDE questionnaires), ocular inflammation, tear stability, and ocular surface damage were analyzed at baseline and after 3 months of treatment. Results: OSDI test scores were significantly lower in both groups (p < 0.001). SANDE frequency test scores also improved statistically, with differences between groups (p = 0.0089 SANDE frequency and p < 0.0119 SANDE severity). There was a greater reduction in ocular redness (ocular inflammation) in the PRGF group (p < 0.0001) and fluorescein tear break-up time was significantly improved in the PRGF group (p = 0.0006). No significant changes were found in terms of ocular surface damage. No adverse events were obtained in either group. Conclusions: The addition of PRGF to the standard treatment of DED, according to the results obtained, proved to be safe and produced an improvement in ocular symptomatology and signs of inflammation, particularly in moderate and severe cases, when compared to standard treatment.

Recovery of Corneal Innervation after Treatment in Dry Eye Disease: A Confocal Microscopy Study

PURPOSE

To analyze the changes in corneal innervation by means of in vivo corneal confocal microscopy (IVCM) in patients diagnosed with Evaporative (EDE) and Aqueous Deficient Dry Eye (ADDE) and treated with a standard treatment for Dry Eye Disease (DED) in combination with Plasma Rich in Growth Factors (PRGF).

METHODS

Eighty-three patients diagnosed with DED were enrolled in this study and included in the EDE or ADDE subtype. The primary variables analyzed were the length, density and number of nerve branches, and the secondary variables were those related to the quantity and stability of the tear film and the subjective response of the patients measured with psychometric questionnaires.

RESULTS

The combined treatment therapy with PRGF outperforms the standard treatment therapy in terms of subbasal nerve plexus regeneration, significantly increasing length, number of branches and nerve density, as well as significantly improving the stability of the tear film (p < 0.05 for all of them), and the most significant changes were located in the ADDE subtype.

CONCLUSIONS

the corneal reinnervation process responds in a different way depending on the treatment prescribed and the subtype of dry eye disease. In vivo confocal microscopy is presented as a powerful technique in the diagnosis and management of neurosensory abnormalities in DED.

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

PURPOSE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

A New Approach for Dry Eye Management By Mucoadhesive In situ Gel of Vitamin B12: Formulation, In vitro and In vivo Assessment

The commitment of the existent study was to develop a mucoadhesive in situ gel systems of vitamin B12 for the management of dry eye disease. The gels were prepared using pluronic F-127 and either of chitosan, carbapol 971P, sodium alginate, or hydroxy propyl methyl cellulose. Drug-excipients compatibility was investigated by means of differential scanning calorimetry and Fourier transform infrared spectroscopy. The gels were characterized for pH, clarity, gelling capacity, viscosity, and adhesion. In vitro release of vitamin B12 from the selected gels was investigated. In vivo effectiveness of the selected gel was determined in rabbit models using Schirmer's and fluorescein tests. The compatibility studies revealed the possibility of incidence of drug/polymer interaction in some formulations. F2-containing pluronic F127 and hydroxypropyl methyl cellulose showed the most appropriate physical characterization and in vitro release profile. The prepared gels showed prolonged drug release with drug release mechanism of combined diffusion and erosion. The in vivo study revealed good effectiveness of the prepared mucoadhesive in situ gel system of vitamin B12 in the treatment of dry eye disease that was comparable to that of the marketed drops.

Diagnosis of Dry Eye Disease Using Principal Component Analysis: A Study in Animal Models of the Disease

PURPOSE

To evaluate whether principal component analysis (PCA) can assess various diagnostic tests of dry eye disease (DED), providing a simplified, more informative measure of disease status than individual clinical test parameters (ICTP).

MATERIALS AND METHODS

ICTP were analyzed using PCA in two groups of normal rabbits (Groups 1 and 2). Group 3, not truly normal, was also assessed. DED was induced in Group 1 by complete dacryoadenectomy; in Groups 2 and 3 by injection of concanavalin A. Tear break up time, tear osmolarity, Schirmer's tear test and rose bengal staining were the ICTP measured in all groups. Statistical analysis including descriptive statistics, t test, correlation coefficients and PCA was done. PCA using ICTP data from Group 1 generated axes; Group 2 and 3 were plotted over these axes.

RESULTS

All groups had induction of DED. Correlations for all ICTP were in the correct direction and were strongest for Group 1 and weakest in Group 3. PCA clearly separated DED and normal eyes. Principal component (PC) 1, made up of nearly equal contributions from the four clinical tests, explained 73% of the variation and provided a means to separate normal from DED. PC 1 values under 0.52 can be mathematically defined as DED. Of all pairwise comparisons, PC 1 vs PC 2 and PC 1 vs PC 3 were the most informative providing excellent spatial separation and additional information regarding DED status.

CONCLUSIONS

PCA proved useful for evaluating DED providing a simpler, more comprehensive assessment than ICTP. PC 1 is a valuable, clinically relevant, and informative metric for DED status and severity having superior diagnostic value and statistical strength compared to ICTP. Spatial information on biplots of PC 1 vs PC 3 is also informative. PCA, and specifically PC 1, has the potential to serve as a biomarker for DED.

Tear ATG5 as a Potential Novel Biomarker in the Diagnosis of Sjögren Syndrome

Autophagy has been suggested to have an important role in the pathogenesis of Sjögren syndrome (SS). We previously identified that autophagy related 5 (ATG5) was elevated in the tear and conjunctival epithelial cells of SS dry eyes (DE) compared to non-SS DE. The purpose of this study was to investigate the role of tear ATG5 as a potential biomarker in the diagnosis of SS. To confirm this hypothesis, we evaluated the tear ATG5 concentration, and other ocular tests (Schirmer I, tear breakup time (TBUT), ocular surface staining (OSS) score, ocular surface disease index (OSDI)) in SS and non-DE, and compared their diagnostic performance to discriminate SS from non-SS DE. Tear ATG5 showed the greatest area under the curve (AUC = 0.984; 95% CI, 0.930 to 0.999) among the tests, and a 94.6% sensitivity and 93.6% specificity at a cutoff value of >4.0 ng/mL/μg. Our data demonstrated that tear ATG5 may be helpful as an ocular biomarker to diagnose and assess SS. In the future, the diagnostic power of tear ATG for SS should be validated.

Tears - more to them than meets the eye: why tears are a good source of biomarkers in Parkinson's disease

Tears are a known source of biomarkers for both ocular and systemic diseases with particular advantages; specifically, the noninvasiveness of sample collection and a unique and increasingly better-defined protein composition. Here, we discuss our rationale for use of tears for discovery of biomarkers for Parkinson's disease (PD). These reasons include literature supporting changes in tear flow and composition in PD, and the interconnections between the ocular surface system and neurons affected in PD. We highlight recent data on the identification of tear biomarkers including oligomeric α-synuclein, associated with neuronal degeneration in PD, in tears of PD patients and discuss possible sources for its release into tears. Challenges and next steps for advancing such biomarkers to clinical usage are highlighted.

Visualization of Tear Clearance Using Anterior Segment Optical Coherence Tomography and Polymethylmethacrylate Particles

We previously reported 2 new methods, anterior segment optical coherence tomography (AS-OCT) and polymethylmethacrylate particles suspended in fluorescein solution (PPF), for the evaluation of tear clearance and rapid tear flow after blinking (tear Krehbiel flow). Here, we investigated age-related OCT tear clearance and tear film thickness (TFT) and the potential correlation of OCT tear clearance and PPF velocity indicative of tear Krehbiel flow. Normal subjects separated into young and older groups received 5 μL of saline solution into the lower conjunctival sac, and an image of the central lower eyelid tear meniscus was captured by AS-OCT immediately and 30 seconds after natural blinking. Tear meniscus height (TMH) and tear meniscus area (TMA) were measured, and their percentage decrease was defined as OCT clearance rate. A Spectralis OCT Anterior Segment Module captured the central corneal tear film layer for TFT measurements. OCT clearance rates were significantly higher in young versus older subjects (P = 0.0002). When all subjects were analyzed, age was significantly and negatively correlated with TMH clearance rate (r = -0.4928, P = 0.0003) and TMA clearance rate (r = -0.4596, P = 0.0008). TFT values were significantly and negatively correlated with age (r = -0.6662, P < 0.0001). A second experiment examined tear Krehbiel flow by measuring PPF velocity in frontal and medial gaze positions. The medial gaze position showed significantly increased PPF velocity compared with the frontal gaze position (P = 0.006). Significant and positive correlations were found between OCT clearance rates and PPF velocity (TMH rate: r = 0.2926, P = 0.0392; TMA rate: r = 0.3274, P = 0.0205). AS-OCT and PPF might be novel techniques for quantitative evaluation of tear clearance and Krehbiel flow.

Diabetic retinopathy: Proteomic approaches to help the differential diagnosis and to understand the underlying molecular mechanisms

Diabetic retinopathy is the most common diabetic eye disease and a leading cause of blindness among patients with diabetes. The appearance and the severity of the symptoms correlate with the duration of diabetes and poor blood glucose level management. Diabetic retinopathy is also categorized as a chronic low-level inflammatory disease; the high blood glucose level promotes the accumulation of the advanced glycation end products and leads to the stimulation of monocytes and macrophages. Examination of protein level alterations in tears using state-of the art proteomics techniques have identified several proteins as possible biomarkers for the different stages of the diabetic retinopathy. Some of the differentially expressed tear proteins have a role in the barrier function of tears linking the diabetic retinopathy with another eye complication of diabetes, namely the diabetic keratopathy resulting in impaired wound healing. Understanding the molecular events leading to the eye complications caused by hyperglycemia may help the identification of novel biomarkers as well as therapeutic targets in order to improve quality of life of diabetic patients.

BIOLOGICAL SIGNIFICANCE

Diabetic retinopathy (DR), the leading cause of blindness among diabetic patients can develop without any serious symptoms therefore the early detection is crucial. Because of the increasing prevalence there is a high need for improved screening methods able to diagnose DR as soon as possible. The non-invasive collection and the relatively high protein concentration make the tear fluid a good source for biomarker discovery helping the early diagnosis. In this work we have reviewed the administration of advanced proteomics techniques used in tear biomarker studies and the identified biomarkers with potential to improve the already existing screening methods for DR detection.

The increase of aqueous tear volume by diquafosol sodium in dry-eye patients with Sjögren's syndrome: a pilot study

PurposeTo investigate the effect of 3% diquafosol sodium ophthalmic solution (DQS) on aqueous tear volume increase in dry-eye patients with Sjögren's syndrome (SS).MethodsIn this pilot study, 17 dry-eye patients with SS (1 male and 16 females; mean age: 66.4 years) were enrolled and underwent topical instillation of two ophthalmic solutions, artificial tears (AT) in one eye and DQS in the fellow eye, in a masked manner. The central lower tear meniscus radius (TMR) curvature was measured before and at 15 min after instillation by video-meniscometry. Simultaneously, all patients self-evaluated their symptoms of wetness and stinging using a visual analog scale (VAS, in millimeters).ResultsTopical instillation of DQS significantly increased the TMR at 15 min (mean: 0.21±0.08 (SD) mm) compared with at baseline (mean: 0.16±0.07 mm) (P<0.001, paired t-test), whereas AT had no effect at baseline (mean: 0.18±0.09 mm) or at 15 min (mean: 0.18±0.09 mm). The visual VAS score of wetness at 15-min post-instillation increased in both groups compared with at baseline. In the DQS-treated eyes, the post-instillation change in TMR from baseline was not correlated with the baseline value of the Schirmer test, corneal staining score, or conjunctival staining score.ConclusionsTopical instillation of DQS increased aqueous tear volume on the ocular surface of dry-eye patients with SS, with its action being independent of lacrimal gland function.

A Comprehensive Review on Dry Eye Disease: Diagnosis, Medical Management, Recent Developments, and Future Challenges

Dry eye syndrome (DES) or keratoconjunctivitis sicca (KCS) is a common disorder of the tear film caused by decreased tear production or increased evaporation and manifests with a wide variety of signs and symptoms. The present review from interpretation of the literature gives detailed information on the prevalence, definition, causes, diagnostic tests, and medical management of dry eye disease. A number of systems contribute to the physiological integrity of the ocular surface and disruption of system may or may not produce symptoms. Therefore accurate diagnosis of dry eyes with no or minimal disruption of physiological function is necessary. The paper also discusses different colloidal drug delivery systems and current challenges in the development of topical ophthalmic drug delivery systems for treatment of KCS. Due to the wide prevalence and number of factors involved, newer, more sensitive diagnostic techniques and novel therapeutic agents have been developed to provide ocular delivery systems with high therapeutic efficacy. The aim of this review is to provide awareness among the patients, health care professionals, and researchers about diagnosis and treatment of KCS and recent developments and future challenges in management of dry eye disease.

New method for evaluation of early phase tear clearance by anterior segment optical coherence tomography

PURPOSE

To describe a new method of measuring early phase tear clearance by anterior segment optical coherence tomography (AS-OCT).

METHODS

Sixty normal subjects were divided into a young group (30 subjects; 29.6 ± 7.2 years) and an elder group (30 subjects; 71.4 ± 10.8 years). AS-OCT (CASIA SS-1000, Tomey, Japan) with customized software was used to record the tear meniscus at the centre of the lower eyelid. Five microlitres of lukewarm saline solution was dropped into the lower conjunctival sac, and an image of the tear meniscus was obtained immediately and again 30 seconds after natural blinking. The tear meniscus height (TMH) and tear meniscus area (TMA) were measured in the AS-OCT images, and the percentage decrease in the TMH and TMA was used as a measure of the tear clearance. Correlations between tear clearance and clinical features including degree of conjunctivochalasis, degree of protrusion of inferior lacrimal punctum, distance of lacrimal punctum from the Marx line and fluorescein clearance rates were also determined in another healthy population consisting of 30 subjects.

RESULTS

The OCT tear clearance rate was 35.2 ± 11% for TMH and 28.1 ± 12.4% for TMA in the young group, and 12.4 ± 7.3% and 6.2 ± 9.1%, respectively in the elder group. The differences were significant for both the TMH (p = 0.017) and the TMA (p = 0.024). The OCT-determined tear clearance was positively correlated with the fluorescein clearance rate, and negatively correlated with the distance between the lacrimal punctum and Marx line, degree of conjunctivochalasis and degree of lacrimal punctum protrusion.

CONCLUSION

AS-OCT can be used as a rapid, non-invasive and quantitative method of determining the early phase tear clearance rate in a normal healthy population.

Association between high tear epidermal growth factor levels and corneal subepithelial fibrosis in dry eye conditions

PURPOSE

To compare tear epidermal growth factor (EGF) concentration in dry eye (DE) conditions and determine correlations between EGF levels and severity of symptoms and ocular surface signs.

METHODS

In this prospective case-control study, 35 patients with DE, including subgroups with meibomian gland disease (MGD), Sjögren's syndrome (SS) aqueous tear deficiency, or neurotrophic keratopathy (NK), and 17 asymptomatic control subjects were evaluated. Symptoms, Schirmer test, fluorescein clearance test (FCT), EGF concentration, dye staining, and the presence of corneal subepithelial fibrosis and meibomian gland (MG) orifice metaplasia were recorded. Tear EGF and the severity of irritation and ocular surface signs were correlated.

RESULTS

Tear EGF was higher in MGD than in the control (P = 0.03) and was lower in SS than in the control (P < 0.0001; MGD (P < 0.05) and NK (P < 0.01) groups. The DE subgroup with results in the FCT > 3 and Schirmer 1 >or= 8 had higher EGF levels than the group with FCT > 3 and Schirmer 1 < 8 and both groups with good tear clearance (P < 0.01). Tear EGF levels correlated inversely with conjunctival (r = -0.49, P = 0.0032) and corneal (r = -0.39, P = 0.022) dye staining and positively with MG orifice metaplasia (r = 0.36, P = 0.03) and corneal subepithelial fibrosis (r = 0.5, P = 0.0006).

CONCLUSIONS

Tear EGF concentration was increased in eyes with MGD, corneal subepithelial fibrosis, and MG orifice metaplasia. Elevated tear EGF may promote development of corneal subepithelial fibrosis and lid margin changes.

Sjögren's syndrome-like ocular surface disease in thrombospondin-1 deficient mice

Thrombospondin-1 (TSP-1) is a major activator of latent transforming growth factor-beta in vitro as well as in vivo. Mice deficient in TSP-1, despite appearing normal at birth, develop a chronic form of ocular surface disease that is marked by increased apoptosis and deterioration in the lacrimal gland, associated dysfunction, and development of inflammatory infiltrates that result in abnormal tears. The increase in CD4(+) T cells in the inflammatory infiltrates of the lacrimal gland, and the presence of anti-Sjögren's syndrome antigen A and anti-Sjögren's syndrome antigen B antibodies in the serum resemble autoimmune Sjögren's syndrome. These mice develop an ocular surface disorder dry eye that includes disruption of the corneal epithelial layer, corneal edema, and a significant decline in conjuctival goblet cells. Externally, several mice develop dry crusty eyes that eventually close. The inflammatory CD4(+) T cells detected in the lacrimal gland, as well as those in the periphery of older TSP-1 null mice, secrete interleukin-17A, a cytokine associated with chronic inflammatory diseases. Antigen-presenting cells, derived from TSP-1 null, but not from wild-type mice, activate T cells to promote the Th17 response. Together, these results indicate that TSP-1 deficiency results in a spontaneous form of chronic dry eye and aberrant histopathology associated with Sjögren's syndrome.

Preliminary effects of oral uridine on the ocular surface in dry eye patients

We designed a randomized, double blinded, 3-months controlled prospective clinical study to investigate effects of oral uridine on the ocular surface in dry eye patients. Twenty-seven patients who diagnosed as dry eye with lower than 5 mm of wetting in the Schirmer strip, with corneal epithelial erosion and who completely followed-up till 3 months were enrolled. Corneal-conjunctival fluorescein staining, non-anesthetic Schirmer test, impression cytology, and Ocular Surface Disease Index (OSDI) were evaluated in the experimental and placebo groups at the baseline, 1 and 3 months after start of medication in a double blinded manner. Fluorescein stain score of the cornea was markedly decreased in oral uridine group compared to the placebo group at 3 months after medication (P=0.032, Mann-Whitney U test). The Schirmer wetting score for the oral uridine group was significantly increased (P=0.001, Wilcoxon signed rank test) at 3 months and its difference between two groups was statistically significant (P=0.030, Mann-Whitney U test). OSDI scores were significantly decreased at 1 and 3 months in treatment group. Oral uridine is effective in treatment of dry eyes.

Cholinoreceptor autoantibodies in Sjögren syndrome

Previous studies have demonstrated that antibodies against cholinoreceptors of exocrine glands correlate with dry mouth in persons with primary Sjögren syndrome (pSS). The aim of the present investigation was to establish if serum IgG antibodies (pSS IgG) were able to interact with cholinoreceptors in rat submandibular gland-dependent stimulation of cyclooxygenase 2 (COX-2) mRNA expression and PGE(2) production. Our findings indicated that pSS IgG-stimulating M(3), M(4), and M(1) cholinoreceptors exerted an increase in COX-2 mRNA without affecting COX-1 mRNA expression and increased PGE(2) production. Inhibitors of phospholipase A(2), COX- s, L-type calcium channel currents, and Ca(2+)-ATPase from sarcoplasmic reticulum prevented the pSS IgG effect on PGE(2) production. An ionophore of calcium mimicked pSS IgG action, suggesting a crucial role of calcium homeostasis in the cholinoreceptor-stimulated increase in PGE(2) production. Moreover, the amounts of PGE(2) in saliva and in sera from persons with pSS were significantly higher than in pre- or post-menopausal women. These findings illustrate the importance of autoantibodies to cholinoreceptors in the generation of chronic inflammation of target tissues in SS.

Tear clearance measurement in patients with dry eye syndrome using quantitative lacrimal scintigraphy

OBJECTIVE

The aim of this study was to evaluate the tear clearance in patients with dry eye syndrome using quantitative lacrimal scintigraphy.

MATERIALS AND METHODS

We investigated 21 patients (42 eyes; 18 women, 3 men; mean age, 63.19 +/- 13.33 years) with dry eye syndrome. Additionally, for the sake of comparison, 12 normal subjects of the same age group (24 eyes; 10 women, 2 men; mean age, 68.25 +/- 2.63 years) were included. Lacrimal scintigraphy, Schirmer-1 test, BUT, and rose bengal ocular surface vital staining were performed in these cases.

RESULTS

According to the results of lacrimal scintigraphy, the mean value of T 1/2 was 4.16 +/- 1.22 minutes and the mean value of RI was 14.15% +/- 2.30% in normal subjects. However, in patients with dry eye syndrome, these values were 20.59 +/- 1.97 minutes and 55.64% +/- 6.90%, respectively. Consistent with the results of ophthalmologic tests, the mean Schirmer-1 value was 12.46 +/- 2.10 mm, the mean value of BUT was 14.36 +/- 3.40 seconds, and the mean staining value of the rose bengal was 1.98 +/- 0.80 in normal subjects, whereas these values were 1.36 +/- 0.49 mm, 5.46 +/- 1.33 seconds, 6.62 +/- 0.86, respectively, in patients with dry eye syndrome. When we compared the results of lacrimal scintigraphy and the results of ophthalmologic tests, an inverse correlation was noted between both the T1/2 and RI values and both the Schirmer-1 and BUT values in all subjects (p < 0.001). However, there was a greater positive correlation between the rose bengal ocular surface staining value and both the T1/2 and RI values in all cases (p < 0.001).

CONCLUSION

In the current study, it was concluded that although the lacrimal drainage system was normal, tear clearance was significantly delayed in dry eye patients. With this study, we have shown that quantitative lacrimal scintigraphy, which is an objective, practical, and noninvasive method, appears to be useful for the assessment of the tear clearance in patients with dry eye syndrome.

Diagnostic performance of tear function tests in Sjogren's syndrome patients

OBJECTIVE

To evaluate the diagnostic performance of the tests included in primary Sjogren's syndrome (SS-I) diagnostic criteria (Schirmer I, break-up time, vital dye staining) and to compare them with other examinations related to the ocular surface status.

METHODS

Clinical and cytological data were collected from 177 patients (62 SS-1, 56 non-SS autoimmune diseases, 59 Sicca syndrome). Tear tests included: a validated questionnaire on symptoms, Schirmer I, Jones test, Ferning test, BUT, corneal aesthesiometry, tear clearance test, lissamine green staining, impression conjunctival cytology. Data were statistically evaluated and sensitivity, specificity, likelihood ratio (LR+), receiver-operating characteristics (ROC) curves were calculated for each test.

RESULTS

Data showed a poor diagnostic performance of Schirmer test I (sensitivity 0.42; specificity 0.76; LR+1.75) and BUT (sensitivity 0.92; specificity 0.17; LR+1.11) (area under the curve in ROC analysis <0.58). Validated subjective symptoms questionnaire (sensitivity 0.89; specificity 0.72; LR+3.18), Jones test (sensitivity 0.60; specificity 0.88; LR+5), corneal aesthesiometry (sensitivity 0.80; specificity 0.67; LR+2.42), and tear clearance test (sensitivity 0.63; specificity 0.84; LR+3.93), all exhibited a high diagnostic performance (area under the curve in the ROC analysis always >0.70). Lissamine green staining exhibited the best performance (sensitivity 0.63; specificity 0.89; LR+5.72) but the result could be distorted by an incorporation bias.

CONCLUSIONS

Our data suggest to implement the items for ocular signs and symptoms contained in many SS-I diagnostic criteria with the use of a validated questionnaire, performance of Jones test, corneal aesthesiometry measurement, and tear clearance rate evaluation.

Reflex epiphora in patients with dry eye symptoms: role of variable time Schirmer-1 test

PURPOSE

To report reflex epiphora in patients with dry eye symptoms and describe the role of variable time Schirmer-1 test.

METHODS

The study was conducted in 16 consecutive dry eye patients (32 eyes), nine male and seven female, aged 16 to 73 years (mean 48.56-/+16.68 years), presenting with reflex epiphora. Each eye was subjected to Schirmer-1 test and the time elapsed in total wetting of the 35 mm strip from its placement into the conjunctiva was noted and test was graded. This was compared with symptomatology, closed chamber infrared thermometry, humidity, fluorescein tear break-up time (FTBUT), fluorescein stain test, and Lissamine green stain.

RESULTS

Schirmer-1 test differentiated reflex epiphora in dry eye patients into groups 0 to 4 based on time it took to wet the 35 mm strip (Group 0 = <=5 min; Group 1 = <=2 min; Group 2 = <=1.5 min; Group 3= <=1 min; Group 4 = <=1/2 min). The score was -0.04 in 8 eyes, -0.03 in 10 eyes, -0.02 in 2 eyes, -0.01 in 6 eyes, and 0.00 in 6 eyes in Groups 4, 3, 2, 1, and 0, respectively. Reflex epiphora had a statistically significant correlation to the symptomatology (p<0.001), lissamine green staining (p<0.001), closed chamber humidity difference (p<0.001), and FTBUT score (p=0.001). Fluorescein stain test and difference in infrared thermometry did not show any correlation. A statistically significant correlation existed between severe and mild to moderate reflex epiphora (p=0.002). However, the two groups separately failed to show any statistically significant relationship with the symptomatology (p=0.16), Lissamine green (p=0.69), humidity difference from close to open eye position (p=0.17), and FTBUT (p=0.25). Thermometry and fluorescein stain test showed no relationship.

CONCLUSIONS

Schirmer-1 test with variable time quantifies reflex epiphora in dry eye patients, which was significantly related to the other tear function tests.

Autoantibodies against cerebral muscarinic cholinoceptors in Sjögren syndrome: functional and pathological implications

Previous studies have demonstrated that antibodies against muscarinic acetylcholine receptors (mAChRs) from exocrine glands, correlates with Sjögren syndrome (SS) in the majority of patients. The aim of the present investigation was to establish if serum IgG antibodies present in SS interacts with cerebral mAChRs. Results show that anti-cerebral IgG are present in the sera of 40% SS patients studied. Autoantibodies were able to interact with mAChRs of cerebral frontal cortex membranes inhibiting the [(3)H]QNB binding to its specific receptor. Moreover, tested by ELISA and dot blot they recognized the synthetic peptides corresponding to the second extracellular loop of human M(1) and M(3) mAChR. In addition, the corresponding affinity-purified anti-M(1) and anti-M(3) peptide IgGs displayed an agonistic activity, stimulating phosphoinositide hydrolysis. The results support the notion that serum IgG autoantibodies in SS patients target cerebral mAChRs may have some role in the pathogenesis of higher cognitive dysfunction present in SS patients.

Tear clearance implications for ocular surface health

Tear clearance/turnover provides a global assessment of the function of the lacrimal functional unit and of tear exchange on the ocular surface. It is an indirect measure of dry eye induced inflammation on the ocular surface. It shows better correlation with the severity of ocular irritation symptoms and corneal epithelial disease in dry eye than the Schirmer 1 test. Delayed tear clearance may prove to be the best measure for identifying patients with tear film disorders who may respond to anti-inflammatory therapy.

The relation between tear film tests in patients with dry eye disease

PURPOSE

The purpose of this report was to investigate the relation between dry eye diagnostic tests.

METHODS

Dry eye patients were enrolled to complete a clinical examination, including the following dry eye tests: a meibomian gland evaluation, tear meniscus height, fluorescein tear breakup time, fluorescein staining of the cornea, the Schirmer 1 test, the phenol red thread test, and rose bengal staining of the conjunctiva. Statistical analyses, including correlation coefficients, the Wilcoxon sign rank test, chi-square test, and logistic regression were used to address the relation between these clinical tests of dry eye.

RESULTS

There was a strong relation between the Schirmer test and fluorescein staining in all four statistical analyses. Similarly, there was also a strong relation between the phenol red thread test and both fluorescein and rose bengal staining. Finally, the results of the Schirmer test were associated with the tear breakup time test in three of four analyses.

CONCLUSIONS

The results indicate that tests of aqueous deficiency (volume or production) are associated with ocular surface desiccation. This important relation should be recognized when choosing dry eye tests as outcomes in clinical trials and epidemiological studies.

Quantitative analysis of lacrimal gland function, apoptotic figures, Fas and Fas ligand expression of lacrimal glands in dry eye patients

The purpose of our study was to examine the correlation between the lacrimal gland function and apoptotic figure, Fas and Fas ligand (FasL) expression in the lacrimal gland. A total of 15 dry eye patients (nine Sjögren's syndrome and six non-Sjögren's syndrome-type dry eye) were recruited for the study. Lacrimal function was evaluated by Schirmer tests 1 and 2. Lacrimal gland biopsies were performed and sections were analyzed by immunohistochemistry using APO2.7, an antibody to Fas and FasL. Quantitative analysis of fluorescein staining was performed by a scanning laser microscopy. Schirmer test 2 results were lower in Sjögren's syndrome-type dry eye and were associated with positive staining of acinar cells with APO2.7 and of infiltrating lymphocytes with FasL. There was a good correlation between the results of Schirmer test 2 and APO2.7 and FasL staining. Lacrimal gland dysfunction is related to the apoptotic figure of acinar cells possibly induced by FasL on the infiltrating lymphocytes.

Spreading of the tears after a blink: velocity and stabilization time in healthy eyes

PURPOSE

To quantify the tear spreading velocity and stabilization time after blinks in healthy patients.

METHODS

Video recordings (magnification, x130) were made of the movements of naturally occurring particles in the tear film while patients blinked naturally. After each blink, tear spreading velocity was computed every 40 milliseconds from particle displacements determined from a frame-by-frame analysis of the records.

RESULTS

After a blink, tears moved rapidly upward over the cornea. Forty milliseconds after passage of the lid, the velocity was 7.34 +/- 2.73 mm/s (mean +/- standard deviation, n = 20). The time to tear stabilization (i.e., zero velocity) was 1.05 +/- 0.30 seconds. The decay of spreading velocity with time was well described by a logarithmic function for all individual patient data (R2 range, 0.88-0.99; n = 20). We have shown that initial velocity and stabilization time are independent descriptors of tear spreading. Meibomian gland expression markedly reduced initial velocity leaving a normal stabilization time, whereas inhalation of an irritant reduced stabilization time leaving a normal initial velocity. In a patient with Sjögren syndrome, punctal plugs rapidly restored initial velocity and stabilization time from near zero values to normal values.

CONCLUSION

We provide normal values for two descriptors of tear spreading, namely initial velocity and time to stabilization. These values can be modified by manipulations that alter tear constituents. Consequently, these descriptors may provide a basis for quantitative, noninvasive tear assessment.

Laser in situ keratomileusis-induced (presumed) neurotrophic epitheliopathy

OBJECTIVE

To evaluate tear production, corneal topography, accuracy of refractive correction, and best spectacle-corrected visual acuity in eyes that had moderate to severe rose bengal staining develop on the flap compared with eyes with little or no staining on the flap, the first few months after laser in situ keratomileusis (LASIK). None of the eyes in this study had significant preoperative dry eye disease.

DESIGN

Retrospective case control study.

PARTICIPANTS

Individual eyes of 19 consecutive patients with moderate to severe punctate epithelial erosions and rose bengal staining on the flap 1 to 3 months after LASIK were compared with eyes of 19 concurrent patients who did not have punctate epithelial erosions or more than trace staining on the flap develop.

METHODS

Nonparametric statistical analyses were used to compare tear secretion, corneal topographic irregularity, spherical equivalent, and visual acuity 3 and 6 months after surgery. Some eyes in both groups also had analysis of tear secretion 1 month after surgery.

MAIN OUTCOME MEASURES

Schirmer's test without anesthesia, the topographic corneal irregularity measurement (CIM), the difference between attempted and achieved spherical equivalent, and the loss of best spectacle-corrected visual acuity.

RESULTS

There was no difference in tear production 1, 3, or 6 months after LASIK in patients who had punctate epithelial erosions and rose bengal staining on the flap develop and those who did not. There was no significant difference in the CIM or mean accuracy of the refractive correction in the two groups, but some patients had a transient decrease in best spectacle-corrected visual acuity. Flap rose bengal staining resolved by 6 months after LASIK in most affected patients.

CONCLUSIONS

LASIK-induced rose bengal staining in patients without preexisting dry eye is likely neurotrophic epitheliopathy, because there is no difference in mean tear production between patients who have significant punctate epithelial erosions and rose bengal staining develop on the flap and those who do not. The signs and symptoms of LASIK-induced (presumed) neurotrophic epitheliopathy tend to resolve approximately 6 months after surgery. This disorder tends to be more common and severe in patients with pre-existing dry eye disease.

Update in Sjögren syndrome

Sjögren syndrome (SS), the second most common autoimmune rheumatic disease, refers to keratoconjunctivitis sicca and xerostomia resulting from immune lymphocytes that infiltrate the lacrimal and salivary glands. However, differential diagnosis remains confusing due to the high prevalence of vague symptoms of dryness, fatigue, and myalgias in the general population. The problems of diagnosis are further compounded by the finding of "positive" antinuclear antibodies in a high percent of the general population. Unless minor salivary gland biopsies are read by experienced observers, nonspecific changes of sialadenitis are frequently confused with the focal lymphocytic infiltrates that are characteristic of SS. The distinction between fibromyalgia patients with low titer antinuclear antibodies and primary SS remains difficult. Even in patients fulfilling strict criteria for SS, the genomic search for critical genes has proven difficult due to the multigenic pattern of inheritance and strong role of currently undefined environmental factors. No single environmental factor has been detected in the majority of SS patients. SS-like syndrome has been detected in certain patients with HTLV-1 and hepatitis C infection, providing clues to pathogenesis. Even in SS patients with marked sicca symptoms, minor salivary gland biopsy shows that almost 50% of glandular cells are still detected on biopsy. These results imply the importance of immune factors such as cytokines and autoantibodies in decreasing neuro-secretory circuits and induction of glandular dysfunction. Of potential importance, an antibody against muscarinic M3 receptor that can decrease secretory function when injected into rodents is frequently found in the sera of SS patients. Newly developed topical and oral therapies can ease the oral and ocular dryness. Orally administered agonists of the muscarinic M3 receptor (pilocarpine and cevimeline) have recently been approved by the US Food and Drug Administration to increase salivary secretion. Topical ocular use of low-dose corticosteroids or cyclosporin may decrease conjunctival surface inflammation. In a Phase II double-blind study, orally administered interferon alpha (150 U) led to improved saliva flow and symptoms. In pregnant patients with evidence of fetal distress, oral dexamethasone is preferred because this agent crosses the placenta effectively. In animal models, antagonists of tumor necrosis factor and inhibitors of de novo pyrimidine synthesis appear promising.