The pathology of dry eye: the interaction between the ocular surface and lacrimal glands

Structural and Molecular Tear Film Changes in Glaucoma

The Tear Film (TF) is a trilaminar and dynamic fluid covering the entire Ocular Surface (OS), consisting of a mucus, aqueous, and lipid layer deeply interacting between them. Because of its structure and functions, TF plays a pivotal role in the preservation of the OS integrity and the quality of vision. Medical therapy for glaucoma is recognized to profoundly disturb the OS homeostasis by altering all components of the ocular surface unit, including TF. The presence of preservatives, the number of daily eye drops instillations, and the duration of therapy are the main contributors to TF changes. From the physio-pathological side, TF alterations are induced by toxic and allergic mechanisms and result from goblet cell and Meibomian gland loss, dysfunction of accessory lacrimal glands, and epithelial disruption. In detail, TF changes are represented by mucus layer thinning, reduced mucin concentration, aqueous layer volume reduction, and lipid layer thinning with increased tear evaporation. Hyper- osmolarity and instability represent the main hallmarks of these changes and are an expression of a iatrogenic form of dry eye. TF undergoes also molecular modifications that primarily reflect a therapy- or disease-induced inflammatory status of the OS. Over the last years, this field of research aimed a progressively growing interest since molecular variations may be considered as potential candidate biomarkers of glaucoma. The aim of this review is to report the main TF changes occurring during glaucoma, exploring the relationship they may have with the glaucoma-related ocular surface disease and the patient quality of life, and their utility as potential biomarkers of disease.

Membrane-associated mucins of the ocular surface: New genes, new protein functions and new biological roles in human and mouse

The mucosal glycocalyx of the ocular surface constitutes the point of interaction between the tear film and the apical epithelial cells. Membrane-associated mucins (MAMs) are the defining molecules of the glycocalyx in all mucosal epithelia. Long recognized for their biophysical properties of hydration, lubrication, anti-adhesion and repulsion, MAMs maintain the wet ocular surface, lubricate the blink, stabilize the tear film and create a physical barrier to the outside world. However, it is increasingly appreciated that MAMs also function as cell surface receptors that transduce information from the outside to the inside of the cell. A number of excellent review articles have provided perspective on the field as it has progressed since 1987, when molecular cloning of the first MAM was reported. The current article provides an update for the ocular surface, placing it into the broad context of findings made in other organ systems, and including new genes, new protein functions and new biological roles. We discuss the epithelial tissue-equivalent with mucosal differentiation, the key model system making these advances possible. In addition, we make the first systematic comparison of MAMs in human and mouse, establishing the basis for using knockout mice for investigations with the complexity of an in vivo system. Lastly, we discuss findings from human genetics/genomics, which are providing clues to new MAM roles previously unimagined. Taken together, this information allows us to generate hypotheses for the next stage of investigation to expand our knowledge of MAM function in intracellular signaling and roles unique to the ocular surface.

Chronic Electrical Stimulation for Tear Secretion: Lacrimal vs. anterior ethmoid nerve

PURPOSE

To evaluate and compare the effect of lacrimal nerve stimulation (LNS) and anterior ethmoid nerve stimulation (AENS) on aqueous tear secretion, and tissue condition following chronic implantation.

METHODS

A neurostimulator was implanted in rabbits adjacent to the (1) lacrimal nerve, and (2) anterior ethmoid nerve. Tear volume was measured with Schirmer test strips after stimulation (2.3-2.8 mA pulses at 30 Hz for 3-5 min), and scores were compared to sham stimulation. Lacrimal gland and nasal septal tissue were evaluated histologically after chronic stimulation (2 weeks-7 months).

RESULTS

LNS increases tear volume by 32% above sham (p < 0.05, n = 5), compared with 133% for AENS (p ≤ 0.01, n = 6). AENS also significantly increases tear secretion in the fellow, non-stimulated eye (p ≤ 0.01, n = 6), as expected from the tearing reflex pathway. Histologically, chronic LNS is well tolerated by surrounding tissues while chronic AENS results in nasal mucosal fibrosis and implant extrusion within 3 weeks.

CONCLUSIONS

AENS is significantly more effective than LNS at enhancing aqueous tear secretion, including the fellow eye. The lacrimal implant is well tolerated, while the nasal implant requires further design optimization to improve tolerability.

Effects of Type 2 Diabetes Mellitus on Gene Expressions of Mouse Meibomian Glands

Purpose: Type 2 Diabetes mellitus (DM) is a major health problem and its ocular complications like orbital infections, cataract and diabetic retinopathy cause blindness. Meibomian gland (MG) dysfunction and dry eye disease are also important ocular complications of type 2 DM but not enough research has been conducted on these complications. Our hypothesis suggests type 2 DM can alter significant gene expressions of MG. In our study, MGs of leptin-deficient spontaneous diabetic and non-diabetic mice were extracted, and gene expression profiles were analyzed with microarray technology.Methods: Mice were divided into two groups; nine Lep ^b/ob spontaneous diabetic mice as type 2 DM group and nine non-diabetic Balb/c mice as controls. Blood glucose levels, tearfilm break-up time and fluorescein scores were measured in both two groups for 12 weeks. MGs were dissected and RNAs were isolated for microarray gene expression analysis. We filtered probes with standard deviation of more than 0.1 and we used 40452 of 45281 probes for processing. We performed fold change analysis and identified which genes are affected, and we analyzed the impact of genes on proteins, pathways and gene ontologies by using various databases.Results: We observed 172 up-regulated and 118 down-regulated genes in type 2 diabetic mice when compared to non-diabetic mice. Interestingly, expression of collagen type I, integrin beta-I binding protein-I, pyruvate dehydrogenase kinase, TNF receptor genes up-regulated with DM; on the other hand, IL-33, cholecystokinin, plasminogen activator, IL-1 and serine peptidase inhibitor genes down-regulated significantly. Also, we have seen a significant decrease in WNT signaling and pentose phosphate pathways-related genes.Conclusion: Our data show these changes in gene expression caused by endocrine and immune mechanisms of type 2 DM which result disrupted homeostasis of epithelial cells of MG. Increased expressions of apoptosis and inflammation-related genes and their effects on related pathways have proven that MGs were negatively affected by type-2 DM.

Presbyopia and the aging eye: Existing refractive approaches and their potential impact on dry eye signs and symptoms

Every part of the human body is subject to aging, including the eye. An increased prevalence of dry eye disease with age is widely acknowledged. Aging threatens ocular surface homeostasis, altering the normal functioning of the lacrimal functional unit and potentially leading to signs and symptoms of dry eye. Additional age-related processes take place within the crystalline lens, leading to presbyopia and cataractogenesis. Correction strategies for presbyopia and cataracts may directly or indirectly challenge the ocular surface. Contact lenses disturb the normal structure of the tear film and can interact negatively with the ocular surface, further deteriorating an already unbalanced tear film in presbyopes, however, newer contact lens designs can overcome some of these issues. Moreover, cataract and corneal refractive surgeries sever corneal nerves and disrupt the corneal epithelium and ocular surface, which can influence surgical outcomes and aggravate dryness symptoms in older age groups. This review summarises the current understanding of how the invasive nature of contact lens wear and cataract and refractive surgery influence signs and symptoms of ocular dryness in an aging population.

Tear Metabolomics in Dry Eye Disease: A Review

Dry eye disease (DED) is a multifactorial syndrome that can be caused by alteration in the quality or quantity of the precorneal tear film. It is considered one of the most common ocular conditions leading patients to seek eye care. The current method for diagnostic evaluations and follow-up examinations of DED is a combination of clinical signs and symptoms determined by clinical tests and questionnaires, respectively. The application of powerful omics technologies has opened new avenues toward analysis of subjects in health and disease. Metabolomics is a new emerging and complementary research discipline to all modern omics in the comprehensive analysis of biological systems. The identification of distinct metabolites and integrated metabolic profiles in patients can potentially inform clinicians at an early stage or during monitoring of disease progression, enhancing diagnosis, prognosis, and the choice of therapy. In ophthalmology, metabolomics has gained considerable attention over the past decade but very limited such studies have been reported on DED. This paper aims to review the application of tear metabolomics in DED.

Relationship between dry eye and glycosylated haemoglobin among diabetics in Ibadan, Nigeria

Introduction

dry eye is a fairly common ocular surface disorder which significantly affects the quality of life of patients. This study aimed to determine the prevalence, and relationship between dry eye and glycosylated haemoglobin (HbA1c) among patients with diabetes mellitus.

Methods

this was a descriptive hospital-based study conducted among patients diagnosed with diabetes mellitus and attending the Diabetic Clinic at a tertiary health facility in Ibadan, south-western Nigeria. Dry eye was assessed using the standardized Ocular Surface Disease Index Questionnaire administered to the eligible respondents on dry eye symptoms. Detailed ocular examination including the tear break-up time (TBUT) and Schirmer I test were carried out and a recent glycosylated haemoglobin value was also obtained.

Results

one hundred and eighty-nine Type 2 diabetic patients were studied, with 68.8% female and a mean age of 60.2 ± 10.3 years. The frequency of dry eye among patients was 21.7% (95% CI, 15.8-27.6). The most commonly reported symptoms of dry eye were “feeling of gritty sensation” (78%, 95% CI, 65.4-90.7) and “blurred vision” (73.2%, 95% CI, 59.6-86.7) while “discomfort in windy areas” (61%, 95% CI, 46.0-75.9) was the most common environmental trigger. No statistically significant correlation was noted between dry eye and HbA1c (r = 0.086, p= 0.239), and age (r = 0.096, p = 0.1)

Conclusion

dry eye is fairly common among patients with diabetes mellitus with most frequent symptoms being gritty sensation and blurred vision. No significant correlation was noted between dry eye and glycosylated haemoglobin (HbA1c).

A new approach of ocular nebulization with vitamin B12 versus oxytocin for the treatment of dry eye disease: an in vivo confocal microscopy study

Purpose: To present a new ocular nebulization therapy for the treatment of dry eye disease (DED) and investigate the efficacy of vitamin B12 (VB12) and oxytocin (OXT) nebulization with clinical parameters and in vivo confocal microscopy (IVCM). Patients and methods: Thirty-eight patients with DED were enrolled, with 19 receiving VB12 nebulization and 19 receiving OXT nebulization twice weekly for 3 months. Clinical signs and symptoms including Ocular Surface Disease Index, self-assessment of light sensitivity and dryness, tear meniscus height, tear break-up time (BUT), and corneal staining, along with IVCM data of basal epithelial cell density, sub-basal dendritic cell (DC) density, nerve density, and nerve tortuosity were acquired at baseline, 1 month, and 3 months after starting treatment. Results: Patients treated with VB12 improved significantly in all signs and symptoms except for nerve tortuosity during the three-month treatment, while OXT demonstrated similar effects apart from BUT and nerve tortuosity. VB12 group revealed a higher BUT at 1 month and 3 months with a higher basal epithelial cell density at 3 months compared with OXT group, and a lower DC density was observed in OXT group at 1 month. Change of basal epithelial cell density was more significant at 3 months in VB12 group, with OXT group showing a significantly higher DC reduction at 1 month. Conclusion: The nebulization therapy delivering VB12 and OXT appears to be effective in improving the symptoms and signs of dry eye, with a relatively stronger effect of BUT elevation and epithelial repair in VB12 and anti-inflammation in OXT nebulization.

Practical guidance for the use of cyclosporine ophthalmic solutions in the management of dry eye disease

Dry eye disease (DED) is a multifactorial disease of ocular surface and tear film, and is a common disorder treated by eye care providers. It is well established that ocular surface inflammation has an important role in the pathophysiology of DED and that anti-inflammatory cyclosporine A (CsA) improves the treatment outcomes of most patients with DED. The purpose of this review is to provide guidance for practitioners in the use of topical CsA for the management of DED to improve patient satisfaction and the quality of life.

Effects of Tear Film Instability on Sensory Responses to Corneal Cold, Mechanical, and Chemical Stimuli

Purpose

To investigate the effects of tear film instability (TFI) induced by sustained tear exposure (STARE) on sensory responses to corneal cold, mechanical, and chemical stimuli.

Methods

Fifteen normal subjects were enrolled. TFI was induced during 10 repeated trials of STARE. Pneumatic cold, mechanical, and chemical stimuli were delivered using a computer-controlled Belmonte esthesiometer on three separate visits. The magnitude of the sensory responses to threshold and suprathreshold (1.25 and 1.50 times threshold levels) stimuli were assessed for intensity, coolness or warmness, irritation and pain, using a 0 (none) to 100 (very strong) scale, before and after STARE trials. Symptoms of ocular discomfort were evaluated using the Current Symptom Questionnaire (CSQ). Repeated measures ANOVA was used for data analysis.

Results

Following STARE trials, the intensity and coolness ratings to cooling stimuli decreased (P = 0.043 and 0.044 for intensity and coolness, respectively), while rated irritation to mechanical stimuli was increased (P = 0.024). The CSQ scores also increased regardless of visits (all P < 0.001). Intensity ratings, coolness to room temperature stimuli and irritation to mechanical and chemical stimuli increased for all suprathreshold stimuli with increasing stimulus levels (P ≤ 0.005).

Conclusions

Repeated TFI induced by STARE affects neurosensory function of the ocular surface. The decrease in reports of cooling and increase in irritation after repeated TFI suggest a complex interaction of neural mechanisms (particularly nonnociceptive cold and nociceptive mechanical) giving rise to ocular surface sensation in humans.

Regeneration of Lacrimal Gland Function to Maintain the Health of the Ocular Surface

Dry eye is a multifactorial disease that is one of the most common diseases worldwide. A major cause of dry eye is the deficiency of aqueous tears, which are mainly secreted from the lacrimal gland. The lacrimal gland plays an important role in maintaining the health of the ocular surface and protecting it from environmental exposure. Dry eye can lead to ocular irritation and discomfort, as well as severe ocular surface diseases (e.g., ocular infections, corneal ulcerations, and ocular surface keratinization). These severe diseases can be induced by an atrophied or injured lacrimal gland; current therapies cannot completely restore the function of lacrimal gland. To develop more definitive therapies, it is important to understand lacrimal gland biology at the molecular level, as well as inflammatory processes affecting the function of the gland. During severe inflammation, the tissue structure of the lacrimal gland is destroyed; it is replaced by scar formation during wound healing, which leads to lacrimal gland dysfunction. Using an animal model of lacrimal gland dysfunction, many investigators have studied molecular mechanisms of inflammation in the lacrimal gland. To restore lacrimal gland function, the lacrimal acini must be restored in their niche. Notably, organ transplantation therapies have been reported to restore lacrimal gland function, directly or indirectly, in animal models. In this review, we describe the current understanding of the lacrimal gland as the therapeutic target for dry eye diseases, as well as recent advances in the field of lacrimal gland cell-based therapy to treat severe dry eye diseases.

Definition and Diagnostic Criteria of Dry Eye Disease: Historical Overview and Future Directions

The definition and diagnostic criteria of dry eye disease (DED) proposed by the Japan Dry Eye Society and other countries are reviewed. The first definition and criteria of DED in Japan were proposed in 1995. In that report, DED was considered a disease of tears, which subsequently damaged ocular epithelia. The presence of subjective symptoms was not included in the criteria. In 2006, a new definition proposed that interactions between the tear film and ocular surface epithelia play important roles in DED. The presence of subjective symptoms, including visual disturbances, changes in tears, and epithelial damage were proposed to be major components of DED, and eyes positive for all three components were diagnosed as "definitive dry eye." A third version was proposed in 2016, which emphasized unstable tear films as a core finding in DED. Following this guideline, eyes with an abnormally low tear film breakup time and the presence of subjective symptoms are considered to have DED. The current definition and criteria are different from those proposed in other countries. For example, the recently published DED definition by the Dry Eye WorkShop II (DEWS II) of the Tear Film and Ocular Surface Society (TFOS) focuses more on the underlying pathogenesis of DED, including inflammation, hyperosmolarity of tears, and neurosensory abnormalities, as well as unstable tear films.

Clinical and biochemical analysis of the ageing tear film

BACKGROUND

Tear film stability is important for healthy visual function, and yet little is known of the ageing mechanisms. The aim of this study was to investigate parallels between biochemical changes and clinical physical parameters, which occur in the tear film of two subject populations differing in age by over 30 years.

METHODS

Two distinct age groups were chosen: 11 'younger' (23.7±2.1 years) and 19 'older' (63.0±4.0 years) subjects. A series of clinical tests were performed to access tear volume, tear film stability and general ocular health. Tear protein analyses from extracted Schirmer strips were conducted with the Agilent 2100 Bioanalyzer.

RESULTS

Clinical investigations highlighted significant differences between the age groups. For example: McMonnies scores (p=0.009) and bulbar redness (p=0.038) were higher for the older group, whereas tear meniscus height was larger (p=0.018) in the younger group. Similarly, relative plasma-derived albumin levels were higher (17.1%±12.4%) in the tears of the older, compared with the younger (5.0%±9.6%) group. A protein peak at ∼23 kDa was observed in 53% of the older group samples but in only 36% of the samples of the younger subjects (p=0.122).

CONCLUSIONS

Distinct differences in tear film composition between the two age groups were observed. Parallels in terms of clinical symptoms which reflected a biochemical response (and vice versa) were found, but specific correlations between clinical measurements and biomarkers for individual subjects were not observed.

Corneal subbasal nerve plexus changes in patients with episodic migraine: an in vivo confocal microscopy study

Background and purpose: It has been generally thought that activation and sensitization of the trigeminovascular system may contribute to the pathogenesis of migraine. Nevertheless, there is little evidence on abnormalities in peripheral trigeminal afferent nerves from humans in vivo. Alterations of corneal nerves from the ophthalmic branch of the trigeminal nerve may support the notion that trigeminal afferent nerves are involved in migraine pathophysiology. The aim of the present study was to investigate the structural changes in corneal subbasal nerve plexus in patients with episodic migraine (EM) with in vivo confocal microscope (IVCM).

Methods: In this cross-sectional observational study, 10 EM patients and 10 age- and sex-matched healthy controls were included. Analysis of IVCM images with Image J software was performed to quantify the changes in the corneal subbasal nerve plexus.

Results: EM patients showed an increase in nerve fiber length (25.0±2.65 vs 22.3±2.41 mm/mm², p=0.047) and nerve fiber density (36.3±7.29 vs 30.5±6.19 fibers/mm², p=0.104) as compared with normal controls, but this difference was not statistically significant. Nerve branching and tortuosity were significantly increased in the EM subjects compared to the normal subjects (91.3±13.8 vs 75.0±14.2 branches/mm², p=0.030 and 2.30±0.46 versus 1.63±0.52, p=0.011, respectively). In addition, nerve sprouts and increased number of Langerhans cells were observed in the EM patients.

Conclusion: The morphologic changes of corneal subbasal nerve plexus and Langerhans cell aggregation suggest the presence of nerve regeneration and inflammation in EM. Furthermore, the alterations of corneal nerves from the ophthalmic branch of the trigeminal nerve offer support for the hypothesis that the peripheral trigeminal system may be involved in the pathogenesis of migraine.

Ocular surface disease in dogs part 1: aetiopathogenesis and clinical signs

Dry eye disease (DED) is a commonly diagnosed disorder in small animals. It has been historically described as a quantitative or qualitative deficiency in tear production; however, the pathogenesis of the disease is much more complex than previously recognised. Ocular surface disorders in people are currently investigated as a dysfunction of what is termed the ‘lacrimal functional unit’, consisting of the ocular surface, including Meibomian glands and conjunctiva, in addition to lacrimal glands, eyelids and sensory and motor innervation. A loss of homeostasis of the tear film leads to the vicious cycle of increased osmolarity and inflammation, with dreadful consequences for the ocular surface in both dogs and humans. Ocular inflammation is the hallmark of DED, reflected in early nonspecific conjunctivitis and later in dramatic changes of the ocular surface. Prompt recognition of the disease, accurate diagnostics and appropriate treatment are paramount in preserving the ocular surface integrity and the patient's comfort. This article discusses the aetiopathogenesis of the condition, and describes the clinical signs, while the second article will look at diagnostics and treatment of ocular surface disorders in dogs.

Rebamipide ophthalmic solution modulates the ratio of T helper cell 17/regulatory T cells in dry eye disease mice

The aim of the present study was to confirm the effect of 2% rebamipide ophthalmic solution on a scopolamine‑induced dry eye (DE) mouse model, and to investigate its effect on the ratio of T helper cell 17 (Th17)/regulatory T cell (Treg) numbers. C57BL/6 mice received subcutaneous injections of scopolamine and were exposed to a low‑humidity environment in order to establish a DE model. Rebamipide eye drops (2%) administered four times daily for 2 weeks, significantly reduced the corneal staining scores and increased the tear film breakup time and tear production in the DE mice. Pathologically, the rebamipide restored the histological changes induced by DE in the cornea, conjunctiva and lacrimal gland. At a molecular level, it downregulated pro‑inflammatory and upregulated anti‑inflammatory cytokines in the conjunctiva and lacrimal gland. Furthermore, the increased Th17 and Treg levels were restored following treatment with rebamipide. In conclusion, the anti‑inflammatory and Th17/Treg balance‑preserving effects of rebamipide may contribute to the treatment of DE in mice.

Comparison of the impact of nesofilcon A hydrogel contact lens on the ocular surface and the comfort of presbyopic and non-presbyopic wearers

AIM

To assess and compare the impact of a daily disposable contact lens (CL) with high water content on the ocular surface and comfort of the presbyopic and non-presbyopic population after one day of use.

METHODS

Totally 20 presbyopes and 30 non-presbyopes non-contact wearers were fitted with nesofilcon A CLs. CL thickness was measured to assess material stability during daily wear, and ocular surface parameters were also assessed. Optical quality was analyzed for all cases. In addition, CL comfort was rated.

RESULTS

No significant differences were found in CL thickness, tear film osmolarity, average tear break-up time, bulbar redness, central corneal thickness, corneal volume, root-mean-square of higher-order aberrations (RMS of HOAs) and vertical and horizontal coma, either as a function of the group or time of use. A significant decrease in tear meniscus height and first break-up of the tear film was found in the presbyopic group (P=0.038; P=0.007 respectively). A decrease in spherical aberration coefficient was found after CL insertion (P=0.031 monofocal CL; P=0.023 low addition multifocal CL; P=0.016 high addition multifocal CL). Multifocal CL were thicker than monofocal CL (P=0.045). Comparison between groups showed more discomfort in presbyopes than non-presbyopes (P=0.003).

CONCLUSION

This study evidence that the behavior of the daily disposable CL with high water content seems to be stable during the day of use. Ocular parameters measured during wear show that CL behavior is the same for presbyopes and non-presbyopes, being more uncomfortable for presbyopes.

Patient satisfaction and self-reported dry eye symptoms in hyperopic patients treated with femtosecond laser in situ keratomileusis

Purpose

To study self-reported patient satisfaction and dry eye symptoms in hyperopic correction with femtosecond laser-assisted in situ keratomileusis (FS-LASIK).

Patients and methods

Ninety-eight eyes (53 patients) were treated with FS-LASIK for hyperopia. Patients’ self-reported dry eye symptoms and satisfaction with near and far vision were graded on the visual analog scale (VAS) preoperatively and 1 month postoperatively.

Results

Ninety-one percent of the eyes with the plano target (54 eyes) achieved an uncorrected distance visual acuity of 20/20 or better. Predictability, defined as spherical equivalent refraction within ±0.5 D of target, was 88% of all eyes. None of the eyes lost two or more Snellen lines of corrected distance visual acuity. There was no significant change in the self-reported dry eye sensation (VAS score from 2.7±2.0 to 2.8±2.0; P=0.66). In 44 monovision patients, satisfaction with both far vision (from 71.2±19.8 to 89.2±8.7; P<0.0001) and near vision (from 51.7±26.2 to 89.3±13.2; P<0.0001) increased significantly. In nine emmetropic patients, satisfaction with neither far vision nor near vision was significantly improved, although there was a clear tendency (from 73.7±23.7 to 86.9±15.3; P=0.22, and from 58.9±29.1 to 81.6±17.4; P=0.11, respectively). In the monovision patient group, far vision satisfaction decreased when dry eye symptoms increased. Monovision patients, as predicted, were more satisfied with their near vision, when postoperative spherical equivalent from target was on the myopic side.

Conclusion

FS-LASIK correction of hyperopia significantly improved patient satisfaction with both near and far vision in monovision patients. Hyperopic patients had no significant changes in postoperative dry eye symptoms compared to preoperative values.

Incidence and management of symptomatic dry eye related to LASIK for myopia, with topical cyclosporine A

Purpose

To evaluate the incidence of transient dry eye associated with LASIK for myopia and the efficacy of topical cyclosporine A administration.

Methods

Group A was formed from 145 (82 female, 63 male) eyes that developed clinically significant dry eye within 1 month post-LASIK and were subjected to cyclosporine A treatment. A “non-symptomatic for dry eye” and age- and gender-matched group (group B) was formed from the same pool of patients to serve as control. Schirmer’s, tear film break-up time (TBUT) and Ocular Surface Disease Index (OSDI) questionnaire were evaluated. Central corneal epithelial thickness (CET) and topographic epithelial thickness variability (TVT) were evaluated as quantitative dry eye objective markers. Subjective patient survey was also assessed.

Results

Mean age was 39.7±6.2 years for the female and 47.67±9.5 years for the male patients, in group A. Schirmer’s test mean preoperative value was 8.4±3.1 mm; and 4.5±3.6 mm at 1 month post-LASIK. Statistically significant decrease from 1 month post-LASIK baseline was found at 12 months (8.2±2.1 mm; P=0.02). Mean preoperative TBUT value was 7.5±2.5 seconds, 6.5±3.1 seconds at 1 month postoperatively, and 7.6±2.0 seconds at 12 months postoperatively, statistically significant to baseline (P=0.04). Preoperatively, CET was 52.37±3.40 µm and TTV was 1.24±0.57 µm, 59.87±3.89 µm, and 2.74±0.57 µm at 1 month post-LASIK respectively and at 12 months, 55.42±2.75 µm and 1.39±0.96 µm. The differences in CET between 12 months post-LASIK vs baseline were statistically significant (P=0.007). The mean preoperative OSDI scores were 11.47±9.97 for group A and 11.79±10.31 for group B (P=0.782), which changed to 23.03±10.17 and 15.13±9.49 at 12 months postoperatively (P<0.05), respectively. Following commencement of cyclosporine A treatment in group A, statistically significant improvement was noted, greater than the one in group B, in all metrics at the 12-month examination in comparison to the 1-month baseline.

Conclusion

Topical cyclosporine A treatment is an effective alternative in the management of LASIK for myopia-related transient dry eye. Optical coherence tomography epithelial mapping may provide an objective benchmark in diagnosing and monitoring this significant disorder and its correlation with visual symptoms.

Comparison of Meibomian Gland Imaging Findings and Lipid Layer Thickness between Primary Sjögren Syndrome and Non-Sjögren Syndrome Dry Eyes

Purpose: To compare meibomian gland (MG) imaging findings and lipid layer thickness (LLT) between patients with primary Sjögren syndrome (SS) dry eyes (DE) and non-SS DE.Methods: A total of 60 patients-30 with SS DE and 30 with non-SS DE were evaluated. Infrared image findings of MGs and LLT were assessed using the LipiView II interferometer.Results: The maximum LLT was significantly lower in the SS DE group. SS DE exhibited significantly higher MG dropout compared to the non-SS DE. Average and maximal LLT showed significant negative correlations with MG dropout in both groups (p<0.05). Conjunctival staining scores showed significant correlations with average and maximum LLT and MG dropout values in the SS DE group (p<0.05).Conclusion: These findings suggest that the new interferometer will be useful in understanding the pathophysiology of SS DE.

Review of Biomarkers in Ocular Matrices: Challenges and Opportunities

Biomarkers provide a powerful and dynamic approach to improve our understanding of the mechanisms underlying ocular diseases with applications in diagnosis, disease modulation or for predicting and monitoring of clinical response to treatment. Defined as measurable indicator of normal or pathological processes, biomarker evaluation has been used extensively in drug development within clinical settings to better comprehend effectiveness of treatment in ocular diseases. Biomarkers in the eye have the advantage of access to multiple ocular matrices via minimally invasive methods. Repeat sampling for biomarker assessment has enabled reproducible objective measures of disease process or biological responses to a drug treatment. This review describes the usage of biomarkers with respect to four commonly sampled ocular matrices in clinic: tears, conjunctiva, aqueous humor and vitreous. Issues that affect the evaluation of biomarkers are discussed along with opportunities to leverage biomarkers such that ultimately, they can be used for customized targeted therapy.

The Effects of Diabetic Duration on Lacrimal Functional Unit in Patients with Type II Diabetes

Purpose

To observe ocular surface changes in Type II diabetic patients with different disease durations and to understand the correlations between clinical parameters and diabetic durations.

Methods

In this cross-sectional, prospective study, 51 healthy controls and 91 patients with Type II diabetes were enrolled. The diabetics were divided into 3 subgroups according to the disease duration, including duration <10 y group, 10 to 20 y group, and ≥21 y group. All subjects underwent clinical ocular examinations, including lipid layer thickness (LLT), blinking rate, tear meniscus height (TMH), noninvasive tear film break-up time (NI-BUT), meibography, superficial punctate keratopathy (SPK) scoring, corneal sensitivity, and Schirmer I test. They were also evaluated using the standard patient evaluation of eye dryness (SPEED) questionnaire.

Results

SPEED score, meiboscore, SPK score, LLT, Schirmer I test, and corneal sensitivity differed significantly between the diabetic and healthy control groups. Further, SPEED score, Schirmer I test, corneal sensitivity, meiboscore, and blink rate significantly differed among the 3 diabetic subgroups and the control group. In diabetics, the SPEED score correlated with the SPK score, blink rate, TMH, and LLT; NI-BUT with TMH, LLT, and blink rate; TMH with the SPK score; Schirmer I test with the SPK score; and corneal sensitivity with the meiboscore. More importantly, the Schirmer I test, corneal sensitivity, and SPEED score negatively correlated with diabetic duration.

Conclusion

Diabetic duration is an important factor that affects functions of the lacrimal functional unit in patients with Type II diabetes. The trends of changes in the ocular parameters vary along the course of diabetes.

Effects of Topical Thymoquinone in an Experimental Dry Eye Model

Objectives

To comparatively evaluate the effects of thymoquinone (TQ), the biologically active main component of volatile oil derived from Nigella sativa seeds, in an experimental dry eye model.

Materials and Methods

A total of 36 BALB/c mice 10 weeks of age were used in the study. The mice were divided into 6 groups of 6 mice. Two groups were negative and positive controls, and the other 4 groups were treated with balanced salt solution, fluorometholone (FML), TQ, or vehicle (Tween80). After 1 week of treatment, the mice were killed and the eyes removed for histopathologic examination and cytokine analysis. Interleukin (IL)-1α tumor necrosis factor-α, interferon-γ, IL-2, IL-6, IL-10, and lactoferrin levels in the conjunctival tissue were measured by multiplex immunobead assay. The presence of inflammatory cells in ocular tissue samples were investigated by hematoxylin-eosin and periodic acid-Schiff staining. Inflammatory T cells containing CXT receptor in the conjunctiva were determined by flow cytometry.

Results

FLML and TQ groups had less inflammatory cell density and more goblet cells compared to the other groups. High levels of IL-1α and IL-2 were found in the TQ group.

Conclusion

TQ treatment was associated with reduced inflammation in pathological examination, but did not significant lower cytokine levels.

Evaluation of the corneal epithelium in non-Sjögren's and Sjögren's dry eyes: an in vivo confocal microscopy study using HRT III RCM

Background

The corneal epithelium is directly affected in dry eye syndrome. Thus, we attempted to describe the morphological features and evaluate the cellular density within the corneal epithelial layers in patients with non-Sjögren’s (NSDE) and Sjögren’s syndrome dry eyes (SSDE) by in vivo confocal microscopy (IVCM).

Methods

Central cornea was prospectively imaged by IVCM in 68 clinically diagnosed aqueous tear-deficient dry eyes and 10 healthy age-matched control eyes. Morphological characteristics of corneal epithelial layers and cellular densities were evaluated by four trained graders from the Doheny Eye Institute.

Results

Corneal epithelium in dry eyes presents morphological changes such as areas of enlarged and irregular shaped cells. In comparison with controls, the density of superficial epithelial cells was decreased in both the NSDE (P < 0.05) and SSDE groups (P < 0.01); the density of the outer layer of wing cells was smaller but not significantly different in NSDE (P > 0.05), but was lower in the SSDE group (P < 0.01); the density of the inner layer of wing cells was decreased in both the NSDE (P < 0.05) and SSDE groups (P < 0.01) and the density of basal epithelial cells was lower in both the NSDE (P < 0.01) and SSDE groups (P = 0.01). For all cell counts, the interclass correlation coefficient showed good agreement between graders (ICC =0.75 to 0.93).

Conclusions

IVCM represents a reliable technique for examining the corneal epithelial microstructural changes associated with dry eyes, as well as for objectively and reproducibly quantifying cell densities within all corneal epithelial layers.

Preservative-Free Prostaglandin Analogs and Prostaglandin/Timolol Fixed Combinations in the Treatment of Glaucoma: Efficacy, Safety and Potential Advantages

Glaucoma therapy-related ocular surface disease (OSD) is a serious pathology with a broad spectrum of insidious clinical presentations and complex pathogenesis that undermines long-term glaucoma care. Preservatives, especially benzalkonium chloride (BAK), contained in topical intraocular pressure-lowering medications frequently cause or aggravate OSD in glaucoma. Management of these patients is challenging, and to date often empirical due to the scarcity of controlled long-term clinical trials. Most of the available data are extracted from case series and retrospective analysis. Preservative-free prostaglandins and prostaglandin/timolol fixed combinations are novel options developed to remove the harmful impact of preservatives, especially BAK, upon ocular tissues. Based on what is currently known on the value of preservative-free antiglaucoma therapies it is tempting to speculate how these new therapies may affect the future medical management of all glaucoma patients. This article provides a comprehensive and critical review of the current literature on preservative-free prostaglandins and preservative-free prostaglandin/timolol fixed combinations.

Dry Eye Disease in Routine Rheumatology Practice

Dry eye disease (DED) is one of the most frequent ophthalmological conditions, with a major impact on patients’ quality of life. Tear film instability and tear hyperosmolarity are considered to play a crucial role in the vicious cycle of dry eye disease. They occur as a result of, either a reduced lacrimal secretion or an excessive evaporation from the tear film. There is a well-known association of DED, not only with autoimmune diseases but also with other systemic diseases and medication. Early diagnosis is important and it is based on the presence of classical symptoms and signs of dry eye in combination with specialized methods. The comprehension of the pathophysiology is significant, as different approaches can be taken to treat DED, depending on the cause and primary source of the disease, as well as on disease severity.

The inflammation influence on corneal surface after frontalis suspension surgery

AIM

To study the influence of frontalis muscle flap suspension on ocular surface by analyzing the clinical features and inflammatory cytokines.

METHODS

A prospective, observational case series. Thirty-one eyes of 25 patients with severe congenital blepharoptosis who underwent frontalis muscle flap suspension surgery with at least 6mo of follow-up were included in the study. The main outcome measures were margin reflex distance 1 (MRD₁), degree of lagophthalmos, ocular surface disease index (OSDI), fluorescein staining (Fl), tear break-up time (BUT), Schirmer I test, and inflammatory cytokine assay.

RESULTS

The degrees of lagophthalmos significantly increased after surgery. The OSDI scores significantly increased 1wk postoperatively and then decreased 4wk after operation. The Fl scores reflected corneal epithelial defects in sixteen patients at early stage postoperatively. The BUT and Schirmer I test values remained stable and did not show change compared to those before surgery. The inflammatory cytokines in conjunctival epithelial cells (including IL-1β, IL-6, IL-8, TNF-α, and IL-17A) significantly increased 1wk after the surgery (P<0.001), then returned to the normal level at 24wk postoperatively. The levels of inflammatory cytokine IL-1β, IL-6, IL-8, TNF-α, and IL-17A elevated significantly and were positively correlated with OSDI and Fl scores.

CONCLUSION

Frontalis muscle flap suspension surgery results in lagophthalmos in early period of post-operation and relieved after months. The elevation of inflammatory cytokines level may participate in the occurrence of corneal epithelial defects at the early postoperative stage.

Uncorrected visual acuity, postoperative astigmatism, and dry eye symptoms are major determinants of patient satisfaction: a comparative, real-life study of femtosecond laser in situ keratomileusis and small incision lenticule extraction for myopia

Purpose

To compare factors affecting patient satisfaction after femtosecond laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) for myopia in the real-life situation study.

Methods

The SMILE group included 100 eyes (51 patients) and the FS-LASIK group 200 eyes (102 patients). In addition to clinical examination, dry eye symptoms and patient satisfaction with far and near vision were reported and graded on the visual analog scale preoperatively and one month after the operation. Case–control pairs were selected for the SMILE patients from FS-LASIK-treated patients to ensure the homogeneity in spherical equivalent refraction, preoperative dry eye, and visual satisfaction.

Results

Eighty percent of SMILE eyes and 83% of FS-LASIK eyes achieved an uncorrected distance visual acuity of 20/20 or better. Predictability (±0.5 D of mean target spherical equivalent refraction) was 91% in SMILE and 93.5% in FS-LASIK. No eyes lost two or more Snellen lines of corrected distance visual acuity. Based on case–control pairs, dry eye symptoms remained the same after one month in the FS-LASIK-treated eyes (P=0.87) but decreased in the SMILE-treated eyes (P=0.01) compared with the preoperative situation. Patient satisfaction with far vision improved significantly in both groups (P<0.001), but satisfaction with near vision improved significantly only in FS-LASIK (P<0.001) and not in SMILE (P=0.58). There was more postoperative astigmatism in SMILE in comparison with FS-LASIK (P=0.002).

Conclusions

In a real-life situation, patients with preoperative dry eye experience were often directed to the SMILE operation, which resulted in beneficial decrease in their dry eye symptoms. Patient satisfaction with far vision decreased with increasing dry eye symptoms and postoperative astigmatism in both SMILE- and FS-LASIK-treated emmetropic patients. Safety, efficacy, and predictability were comparable in both treatments.

Tear Production Levels and Dry Eye Disease Severity in a Large Norwegian Cohort

PURPOSE

To determine if the Schirmer I test (without anesthesia) cut-off value is a predictor of dry eye severity in a large Norwegian cohort of dry eye disease (DED) patients, which are grouped into six levels of tear production.

METHODS

Patients (n = 1090) with DED of different etiologies received an extensive dry eye work-up: osmolarity (Osm), tear meniscus height (TMH), tear film break-up time (TFBUT), ocular protection index (OPI), ocular surface staining (OSS), Schirmer I test (ST), meibum expressibility (ME), and meibum quality (MQ). Classification of dry eye severity level (DESL) and diagnosis of meibomian gland dysfunction (MGD) were also included. The cohort was divided into six groups: below and above cut-off values of 5 (groups 1 and 2), 10 (groups 3 and 4), and 15 mm (groups 5 and 6) of ST. Mann-Whitney test and Chi-Square test were used for group comparison of parameters (p ≤ 0.05).

RESULTS

The groups 1, 3, and 5 had values indicating more severe DED than the groups 2, 4, 6 with significant difference in DESL, Osm, TFBUT, OPI, OSS, and TMH. Regardless of the choice of cut-off values, there was no statistically significant difference in ME, MQ, and MGD between groups below and above selected cut-off value. When gender difference was considered in each group, significant difference was only observed for DESL (groups 2, 4, and 5), TFBUT (groups 2, 4, and 5), OPI (groups 2 and 6), and ME (group1).

CONCLUSIONS

Schirmer I is a robust discriminator for DESL, Osm, TFBUT, OPI, OSS, and TMH, but not for ME, MQ, and MGD. Patients with lower tear production levels presented with more severe DED at all three defined cut-off values. Interestingly, the differences in the mean values of DESL were minimal although statistically significant. Thus, the clinical value of different Schirmer levels appears to be limited.

Botulinum toxin injection and tear production

PURPOSE OF REVIEW

In 1980, botulinum toxin type A (BTX-A) was introduced for the treatment of strabismus and benign essential blepharospasm. Since then, a number of additional indications have been introduced, which continue to expand, providing less invasive solutions in managing different ophthalmic conditions.

RECENT FINDINGS

Successful trials of BTX-A injection into the lacrimal gland have been reported for the treatment of epiphora caused by primary lacrimal gland hyperlacrimation, functional tearing, gustatory tearing, and lacrimal outflow obstruction. This is achieved through blockage of the cholinergic receptors by BTX-A at the glandular level. Interestingly, BTX-A has also been found to be useful in treating patients with dry eyes by compromising the tear drainage from the eye through injection of BTX-A in the medial part of the lower eyelid. BTX-A may help provide effective relief for patients who have two different ophthalmic comorbidities such as benign essential blepharospasm and dry eye.

SUMMARY

Better understanding of the mechanism of BTX-A action in the treatment of the growing applications in ophthalmology helps provide relatively noninvasive solutions for patients. Full awareness of possible side effects of BTX-A and the optimal way to manage them is vital for the success of this treatment option.

Innate and Adaptive Cell Populations Driving Inflammation in Dry Eye Disease

Dry eye disease (DED) is the most common ocular disease and affects millions of individuals worldwide. DED encompasses a heterogeneous group of diseases that can be generally divided into two forms including aqueous-deficient and evaporative DED. Evidence suggests that these conditions arise from either failure of lacrimal gland secretion or low tear film quality. In its secondary form, DED is often associated with autoimmune diseases such as Sjögren's syndrome and rheumatoid arthritis. Current treatment strategies for DED are limited to anti-inflammatory medications that target the immune system as the source of deleterious inflammation and tissue injury. However, there is a lack of understanding of the underlying pathogenesis of DED, and subsequently, there are very few effective treatment strategies. The gap in our knowledge of the etiology of primary DED is in part because the majority of research in DED focused on secondary autoimmune causes. This review focuses on what is currently understood about the contribution of innate and adaptive immune cell populations in the pathogenesis of DED and highlights the need to continue investigating the central role of immunity driving DED.

Topical Quercetin and Resveratrol Protect the Ocular Surface in Experimental Dry Eye Disease

Purpose: To determine the anti-inflammatory effect of quercetin (QCT), resveratrol (RES), and their combination in a dry eye disease (DED) model. Methods: 0.01% QCT, 0.1% RES, 0.01% QCT + 0.1% RES (QCT + RES) or vehicle were topically applied in a desiccating stress (DS) mice model. CD4⁺ T cells isolated from DS-exposed mice were transferred to athymic recipient mice. Corneal fluorescein staining, tear production, and tear cytokine levels were evaluated in DS-exposed mice, and conjunctival CD4⁺ T cell infiltration was evaluated in recipient mice. Results: QCT (p < 0.001) and QCT + RES (p < 0.05) reduced corneal staining in DS-exposed mice. IL-1α tear concentration was reduced by QCT, RES, and QCT + RES (p < 0.05, 0.01 and 0.01, respectively) compared to DS + vehicle mice. CD4⁺ T cells increased in recipients of DS-exposed mice (p < 0.05) and were lower in recipients of QCT- and RES-treated mice (p < 0.05). Conclusion: The anti-inflammatory effect of QCT, RES, and QCT + RES on DED-experimental model suggests that their topical application could be used for DED treatment.

Are Serum Vitamin D Levels Associated With Dry Eye Disease? Results From the Study Group for Environmental Eye Disease

Objectives

Dry eye disease (DED) is an increasingly important public health problem in Korea. Previous studies conducted in Korea have reported inconsistent results regarding the protective effects of vitamin D on DED, and these discrepancies may be related to the relatively simple questionnaire that has been used. Thus, we evaluated the association of serum vitamin D levels with DED using the ocular surface disease index (OSDI).

Methods

The present study evaluated data from participants in the Study Group for Environmental Eye Disease (2014-2015). This group included data from 752 participants, and data from 740 participants (253 men and 487 women) were analyzed in the present study. DED severity was evaluated using the OSDI.

Results

Higher serum vitamin D levels were associated with a non-significantly reduced risk of DED in the crude analysis (odds ratio [OR], 0.991; 95% confidence interval [CI], 0.971 to 1.011) and in the adjusted analysis (OR, 0.988; 95% CI, 0.966 to 1.010). In the crude analysis of no/mild DED vs. moderate/severe DED, men exhibited a decreased risk with increasing serum vitamin D levels (OR, 0.999; 95% CI, 0.950 to 1.051), while women exhibited an increased risk (OR, 1.003; 95% CI, 0.979 to 1.027). In these analyses, we found no significant associations.

Conclusions

The findings of the present study support previous reports that serum vitamin D levels are not associated with DED.

TH17 cells mediate inflammation in a novel model of spontaneous experimental autoimmune lacrimal keratoconjunctivitis with neural damage

BACKGROUND

Dry eye disease (DED) affects one third of the population worldwide. In prior studies, experimental autoimmune lacrimal keratoconjunctivitis (EALK) induced by desiccating stress in mice has been used as a model of DED. This model is complicated by a requirement for exogenous epithelial cell injury and administration of anticholinergic agents with broad immunologic effects.

OBJECTIVE

We sought to develop a novel mouse model of EALK and to demonstrate the responsible pathogenic mechanisms.

METHODS

CD4+CD45RBhigh naive T cells with and without CD4+CD45RBlow regulatory T cells were adoptively transferred to C57BL/10 recombination-activating gene 2 (Rag2)-/- mice. The eyes, draining lymph nodes, lacrimal glands, and surrounding tissues of mice with and without spontaneous keratoconjunctivitis were evaluated for histopathologic changes, cellular infiltration, and cytokine production in tissues and isolated cells. Furthermore, the integrity of the corneal nerves was evaluated using whole-tissue immunofluorescence imaging. Gene-deficient naive T cells or RAG2-deficient hosts were evaluated to assess the roles of IFN-γ, IL-17A, and IL-23 in disease pathogenesis. Finally, cytokine levels were determined in the tears of patients with DED.

RESULTS

EALK developed spontaneously in C57BL/10 Rag2-/- mice after adoptive transfer of CD4+CD45RBhigh naive T cells and was characterized by infiltration of CD4+ T cells, macrophages, and neutrophils. In addition to lacrimal keratoconjunctivitis, mice had damage to the corneal nerve, which connects components of the lacrimal functional unit. Pathogenic T-cell differentiation was dependent on IL-23p40 and controlled by cotransferred CD4+CD45RBlow regulatory T cells. TH17 rather than TH1 CD4+ cells were primarily responsible for EALK, even though levels of both IL-17 and IFN-γ were increased in inflammatory tissues, likely because of their ability to drive expression of CXC chemokines within the cornea and the subsequent influx of myeloid cells. Consistent with the findings of this model, the tears of patients with DED had increased levels of inflammatory cytokines, including IL-17A and TNF-α.

CONCLUSION

We describe a novel model of spontaneous EALK that supports a role for TH17 cells in disease pathogenesis and that will contribute to our understanding of autoimmune lacrimal keratoconjunctivitis in many human eye diseases, including DED.

Effects of ambient humidity on the Cochet-Bonnet aesthesiometer

PURPOSE

The Cochet-Bonnet (COBO) aesthesiometer is the current standard in corneal sensitivity assessment. This study investigates the influence of ambient room humidity levels on the stimulus force exerted by the instrument.

METHODS

A COBO instrument (Luneau Opthalmologie) with 0.12 mm nominal nylon filament diameter was placed in an environment chamber (Electro-tech systems Inc. PA, USA) at 25 °C and relative humidity (%RH) set to either 20-80%, in 10% steps. After 12 h in the chamber at a chosen %RH level, the instrument was removed and exerted force measured by pressing the nylon filament onto the plate of an analytical microbalance (Mettler-Toledo AB265; precision ±0.0001 g) at a perpendicular angle, by a predetermined amount. Exerted force onto the microbalance was recorded in grams for a specified filament length. Procedure was repeated for filament lengths 10-60 mm, in 5 mm steps. The instrument was returned to the chamber and procedure repeated 5 times, before repeating at the next %RH setting (random order). Measurements at each filament lengths were compared using one-way ANOVA and post-hoc Tukey's range test. A p-value < 0.05 denoted statistical significance.

RESULTS

Significant differences in exerted force were observed with alteration in %RH levels for each filament length (all p < 0.001). Exerted force decreased significantly with an increase in %RH for all filament lengths, with the average force decreasing by 15% with each 10% rise in %RH.

CONCLUSIONS

This study confirms previous suggestions that the rigidity of the COBO nylon filament is affected by ambient room humidity levels, with implications on the stimulus force delivered by the instrument. A conversion table is provided for converting filament lengths to pressure for a range of relative humidity levels.

Efficacy and safety of using topical cyclosporine A for treatment of moderate to severe dry eye disease

Objective

To investigate and evaluate the efficacy and safety of topical cyclosporine A for treatment of moderate to severe dry eye disease.

Materials and methods

This is a prospective study of patients with moderate to severe dry eye syndrome were recruited. All cases were selected from patients attending the ophthalmic outpatient clinic of Research institute of ophthalmology. Eligible patients were at least 21 years of age with a confirmed diagnosis of keratoconjunctivitis sicca with or without Sjogren's syndrome refractory to conventional management.

The medication used in this study were unit dose vials of unpreserved cyclosporine A 0.05% used twice daily.

The protocol was composed of a 2-week washout phase, a 12-week treatment phase, and a 4-week post treatment phase. Patients were evaluated at weeks 4, 8, 12 during the treatment phase. During these visits patients were evaluated for changes from base line in Schirmer test, rose Bengal staining, superficial punctuate erosions, BUT, impression cytology, symptoms of ocular discomfort and visual acuity. After completion of the treatment phase, patients were also evaluated at post treatment week 4, during this visit patients were assessed for Schirmer test, rose Bengal staining, superficial punctuate erosion, BUT, impression cytology, symptoms of ocular discomfort and visual acuity.

Results

Thirty two cases in the mean age of 47 (12.9), range [20–67] years; four (13%) male and 28 (87%) female were recruited in the current study. Out of them, 12 (38%) cases had Sjogren syndrome. Visual acuity improved significantly (p = 0.012), BUT (p < 0.0001) for both eyes, Schirmer measurements (p < 0.0001 and p = 0.029 for OD and OS, respectively).

Conclusions

Cyclosporine A ophthalmic emulsion 0.05% has been demonstrated to be effective and safe in human clinical trials. It reduces signs and symptoms of dry eye disease, with the fact that its effect continued to occur significantly within the treatment periods as well as improvement of ocular condition kept on, actually more slowly towards stability, despite the drug has already stopped.

Eficácia dos colírios ciclosporina e tacrolimo no tratamento de ceratoconjuntivite seca em cães

RESUMO O objetivo deste estudo foi avaliar os efeitos do tacrolimo e da ciclosporina na produção lacrimal de cães com ceratoconjuntivite seca (CCS) durante 90 dias. Para tanto, foram utilizados colírios de tacrolimo 0,02% (TcL) e ciclosporina 0,1% (CsA) em 14 cães com CCS. Os animais foram distribuídos em dois grupos e avaliados antes do início do tratamento (T0) e aos 15 (T1), 30 (T2), 45 (T3), 60 (T4), 75 (T5) e 90 (T6) dias após o início do tratamento. Na avaliação clínica, observou-se maior redução da secreção ocular, da opacidade e do edema corneano e da vascularização conjuntival. no grupo tacrolimo. No teste de Schirmer, verificou-se produção basal de 6(4,07 e 5,86(2,85mm/min no TcL e CsA, respectivamente, com aumento significativo da produção lacrimal em ambos os grupos, contudo houve aumento significativo da produção lacrimal a partir dos 15 dias de tratamento no grupo TcL (17,88(5,51mm/min), mas apenas a partir dos 45 dias no grupo CsA (11,86(4,74mm/min). Conclui-se que o uso do colírio tacrolimo aumentou em 68,83% a produção lacrimal em 90 dias de tratamento, comparado com a ciclosporina (56,82%), além de diminuir as manifestações clínicas inerentes à CCS, quando comparado à terapia com ciclosporina.

Evaluating the novel application of cyclosporine 0.1% in ocular surface disease

INTRODUCTION

Ocular surface disease (OSD) is a highly prevalent symptomatic condition caused by dry eye disease (DED), intrinsic, environmental, or iatrogenic causes. It affects patient's visual function and quality of life. Its pathophysiology is centered on tear hyperosmolarity, inflammation, and epithelial damage. Current management is suboptimal and includes artificial tear supplementation and short-term use of topical steroids in severe cases. The recent approval of cyclosporine 0.1% has transformed management strategies of severe DED and moderate-to-severe OSD. Areas covered: This review summarizes existing information on the efficacy, safety, and tolerability of the new cyclosporine 0.1% formulation. Expert opinion: Topical cyclosporine A 0.1% represents a promising, novel medication for the management of DED, Meibomian gland dysfunction, and inflammatory OSD. It is primarily beneficial for those patients requiring topical immunomodulatory therapy. This topical formulation also has the potential to meaningfully improve the management of moderate-to-severe glaucoma therapy-related OSD. Currently there is limited published clinical data concerning the efficacy of topical cyclosporine. There are, however, theoretical advantages when comparing this cyclosporine formulation with other established commercial preparations. Future research is needed to delineate the precise role and value of this medication.

Schirmer test changes after 20 gauge and 23 gauge pars plana vitrectomy

Objective: To evaluate the short-term changes in Schirmer I test (ST) after pars plana vitrectomy and to compare the results between 23 gauge and 20 gauge vitrectomy surgeries.

Methods: 42 patients who underwent pars plana vitrectomy for posterior segment diseases were included in this prospective, non-randomized, comparative study. The choice of sclerotomy gauge was at the surgeons’ discretion. ST values were recorded before and at 1 and 3 months after vitrectomy.

Results: 20 patients in 23 gauge and 22 patients in 20-gauge group with a mean age of 59.9 ± 13.5 years were included. The mean preoperative ST values decreased significantly in both groups at 1 and 3 months after surgery (all P < 0.01). The ST values in the fellow eyes were the same, at baseline and during the follow up (P > 0.05). At 3 months visit, 15 eyes (35.7%) had abnormal ST measurements. There was no statistically significant difference in the changes in the ST measurements between the two groups at one month (P = 0.7), however, 3 months after surgery, the mean decrease in the ST measurements was significantly higher in the 20 gauge group (P = 0.03). At 3 months, 4 eyes in the 23 gauge group (20%) and 11 eyes in the 20 gauge group (50%) had abnormal ST measurements (P = 0.05).

Conclusions: Although both 20 and 23-gauge vitrectomy decrease the ST measurements postoperatively, the value is less affected by the 23-gauge vitrectomy.

Botulinum neurotoxin A injection for the treatment of epiphora with patent lacrymal ducts

HEADINGS

Retrospective longitudinal study to evaluate the efficacy of botulinum neurotoxin A (BoNT/A) therapy for epiphora with patent lacrimal ducts.

BACKGROUND/PURPOSE

BoNT/A has been used since 2000 in axillary hyperhidrosis to reduce sweat secretion. Some isolated cases of hyperlacrimation or crocodile tear syndrome have been treated with BoNT/A on this basis. We report our experience in the treatment of tearing despite patent lacrimal ducts by BoNT/A injection into the lacrimal gland.

METHODS

We reviewed qualitative and quantitative criteria to evaluate the degree of improvement of epiphora after BoNT/A injections in the palpebral lobe of the lacrimal gland in patients referred for epiphora despite patent lacrimal ducts between 2009 and 2016. Epiphora was graded using a functional questionnaire, Munk score and Schirmer test performed before and after the injections. Side effects were recorded.

RESULTS

Sixty-five palpebral lacrimal glands of forty-two patients with epiphora despite patent lacrimal ducts, of mean age 65 years, sex ratio 0.8, were treated with BoNT/A (IncobotulinumtoxinA, XEOMIN^®, MERZ Pharma France) from April 2009 to April 2016. The etiology of the epiphora was represented by 56 paroxysmal lacrimal hypersecretion, 2 crocodile tear syndrome and 7 facial palsies. No conventional medical or surgical treatment had been effective in these cases. The technique of injection, dilution and dosage of BoNT/A were specific. We re-injected 33/65 cases a second time upon patient request due to recurrence of epiphora, 16/65 cases three times, 8/65 cases four times, 6/65 cases five times and 3/65 six times. The Schirmer's test measured a decrease of lacrimal secretion in 51/65 glands (78%) after the first botulinum neurotoxin injection. Side effects were limited to ptosis in 2 cases (3%) and six patients (9%) with rapidly regressing diplopia. Two patients experienced immediate lacrimal gland hematoma (3%) with no sequelae. The authors describe the injection techniques, the dosage, the volume and concentration of BoNT/A.

CONCLUSION

Patients with intractable epiphora despite patent lacrimal ducts can be effectively treated with BoNT/A (IncobotulinumtoxinA) injection into the palpebral lobe of the lacrimal gland. Most of the patients (80%) were very satisfied with few side effects (hematoma, ptosis or mild diplopia lasting from 3 days to 3 weeks). More studies are needed to delineate which types of epiphora can be treated with BoNT A.

Corneal Tissue From Dry Eye Donors Leads to Enhanced Graft Rejection

PURPOSE

To assess the effect of dry eye disease (DED) in graft donors on dendritic cell (DC) maturation, host T-cell sensitization, and corneal allograft rejection.

METHODS

Corneas of control (healthy donor) and DED mice (C57BL/6) were transplanted onto fully allogeneic naive BALB/c recipients (n = 10 mice/group). Long-term allograft survival was evaluated for 8 weeks. Corneas and draining lymph nodes (dLNs) were harvested at posttransplantation day 14 (n = 5 mice/group). The frequencies of MHCII CD11c DCs in the donor corneas and host dLNs and the frequencies of interferon (IFN)-γ and IL-17 CD4 T cells and Foxp3 expression by Tregs in host dLNs were investigated using flow cytometry. The enzyme-linked immunospot assay was used to assess host T-cell allosensitization through direct and indirect pathways (n = 3/group).

RESULTS

Recipients of DED donor corneas showed significantly reduced graft survival (10%) compared with control mice (50% survival, P = 0.022), and had significantly increased frequencies of mature DCs in the grafted cornea (DED donor 44.0% ± 0.36% vs. healthy donor 35.4 ± 0.5%; P < 0.0001) and host dLNs (DED donor 25.1% ± 0.66% vs. healthy donor 13.7% ± 1.6%; P = 0.005). Frequencies of IFN-γ and IL-17 T cells were increased in the dLNs of recipients of DED corneas, whereas the expression (mean fluorescence intensity) of Foxp3 in Tregs was decreased significantly in these mice (DED donor 6004 ± 193 vs. healthy donor 6806 ± 81; P = 0.0002). Enzyme-linked immunospot analysis showed that the direct pathway of allosensitization was significantly amplified in recipients of grafts with DED (P = 0.0146).

CONCLUSIONS

Our results indicate that DED in the donor is a significant risk factor for subsequent corneal allograft rejection.