Frequent association of delayed tear clearance in ocular irritation

A major review of punctal stenosis: Updated anatomy, epidemiology, etiology, and clinical presentation

We aim to provide a detailed and updated literature review on the epidemiology, etiology, clinical presentations, histopathology, and ultrastructural features of punctal stenosis. There are inconsistencies in the definition and staging of punctal stenosis. While advanced optical coherence tomography imaging techniques have revolutionized the way the punctum and vertical canaliculi are assessed or monitored following treatment, the planes of measurement to characterize punctum anatomy need to evolve further. The current criteria for diagnosing and grading punctal stenosis are inadequate and based on empirical clinical findings. There is increasing evidence of the role of lymphocytes and myofibroblasts in the pathogenesis of punctal stenosis. There is a need for a uniform assessment of punctal stenosis and a uniform reporting of severity that would help standardize the several management options available in the lacrimal armamentarium.

Recent progress of nanomedicine in managing dry eye disease

Background

Dry eye disease (DED) is a commonly reported ocular complaint that has garnered significant attention in recent research. The global occurrence of DED ranges from 5% to 50%, impacting a substantial proportion of individuals worldwide with increasing frequency. Although topical administration remains the mainstream drug delivery method for ocular diseases, it suffers from drawbacks such as low bioavailability, rapid drug metabolism, and frequent administration requirements. Fortunately, the advancements in nanomedicine offer effective solutions to address the aforementioned issues and provide significant assistance in the treatment of DED.

Main text

DED is considered a multifactorial disease of the ocular surface and tear film, in which the integrity of tear film function and structure plays a crucial role in maintaining the homeostasis of the ocular surface. The conventional treatment for DED involves the utilization of artificial tear products, cyclosporin, corticosteroids, mucin secretagogues, and nonsteroidal anti-inflammatory drugs. Furthermore, nanomedicine is presently a significant field of study, with numerous clinical trials underway for various nanotherapeutics including nanoemulsions, nanosuspensions, liposomes, and micelles. Notably, some of these innovative nanoformulations have already received FDA approval as novel remedies for DED, and the advancement of nanomedicine is poised to offer enhanced prospects to solve the shortcomings of existing treatments for DED partially.

Conclusions

This article provides an overview of the latest advancements in nanomedicine for DED treatment, while the field of DED treatment is expected to witness a remarkable breakthrough shortly with the development of nanomedicine, bringing promising prospects for patients worldwide suffering conditions.

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.

Automation of dry eye disease quantitative assessment: A review

Dry eye disease (DED) is a common eye condition worldwide and a primary reason for visits to the ophthalmologist. DED diagnosis is performed through a combination of tests, some of which are unfortunately invasive, non‐reproducible and lack accuracy. The following review describes methods that diagnose and measure the extent of eye dryness, enabling clinicians to quantify its severity. Our aim with this paper is to review classical methods as well as those that incorporate automation. For only four ways of quantifying DED, we take a deeper look into what main elements can benefit from automation and the different ways studies have incorporated it. Like numerous medical fields, Artificial Intelligence (AI) appears to be the path towards quality DED diagnosis. This review categorises diagnostic methods into the following: classical, semi‐automated and promising AI‐based automated methods.

Changes in Tears Monocyte Chemoattractant Protein-1 Level After External Dacryocystorhinostomy in Primary Acquired Nasolacrimal Duct Obstruction

BACKGROUND

The authors aimed to define tears monocyte chemoattractant protein-1 (MCP-1) changes after external dacryocystorhinostomy surgery.

MATERIALS AND METHODS

Tears samples were collected with a Schirmer strip and stored in Eppendorf tubes at -80°C. At the end of the study, the papers were cut into small pieces and incubated with phosphate-buffered saline solution. Monocyte chemoattractant protein-1 levels were determined by using an enzyme-linked immunosorbent assays kit.

RESULTS

The MCP-1 levels were 498.66±101.35, 576.40±149.78, 422.53±85.94, and 436.96±81.38 ng/L before surgery, in the first week, the first, and third months after surgery, respectively. Its level significantly increased in the first week compared with the preoperative level ( P <0.001). There was a prominent decrease in the postoperative first month ( P <0.001). In the third postoperative month, the mean MCP-1 level was not significantly increased compared with the postoperative first month ( P =0.196).

CONCLUSION

The tears MCP-1 level was significantly decreased after external dacryocystorhinostomy surgery.

Modern approach to the treatment of dry eye, a complex multifactorial disease: a P.I.C.A.S.S.O. board review

Dry eye disease (DED) is a growing public health concern affecting quality of life and visual function, with a significant socio-economic impact. It is characterised by the loss of homoeostasis, resulting in tear film instability, hyperosmolarity and inflammation of the ocular surface. If the innate immune response is unable to cope with internal bodily or environmental adverse conditions, the persistent, self-maintaining vicious circle of inflammation leads to the chronic form of the disease. Treatment of DED should be aimed at the restoration of the homoeostasis of the ocular surface system. A proper diagnostic approach is fundamental to define the relevance and importance of each of the DED main pathogenic factors, namely tear film instability, epithelial damage and inflammation. Consideration also needs to be given concerning two other pathogenic elements: lid margin changes and nerve damage. All the factors that maintain the vicious circle of DED in the patient's clinical presentation have to be considered and possibly treated simultaneously. The treatment should be long-lasting and personalised since it has to be adapted to the different clinical conditions observed along the course of the disease. Since DED treatment is frequently unable to provide fast and complete relief from symptoms, empathy with patients and willingness to explain to them the natural history of the disease are mandatory to improve patients' compliance. Furthermore, patients should be instructed about the possible need to increase the frequency and/or change the type of treatment according to the fluctuation of symptoms, following a preplanned rescue regimen.

The Relationship between Subjective Symptoms and Quality of Life in Conjunctivochalasis Patients

The purpose of this study was to evaluate the differences in subjective symptoms between patients with conjunctivochalasis (CCh) and dry eye (DE), and examine the relationship between subjective symptoms and quality of life (QOL). In 75 eyes of 75 CCh patients and 122 eyes of 122 DE patients, 12 subjective symptoms classified into four groups depending on the mechanisms associated with symptoms (ITF: instability of tear film, IF: increased friction, R: reflex, and DTC: delayed tear clearance) were evaluated by use of a visual analogue scale (VAS). Fifteen items related to DE symptoms and their influence on daily life were evaluated by use of the dry eye-related quality-of-life score (DEQS) questionnaire, with overall degree of QOL impairment calculated as a QOL score. The correlation between the Total VAS score and QOL score were evaluated. Between the CCh and DE patients, significant differences in subjective symptoms were found in eye dryness, pain, tearing sensitivity to light, and heavy eyelids, while tearing was higher in CCh. A significant strong correlation was found between QOL score and Total VAS score, ITF, and IF in CCh patients. The QOL of CCh patients is strongly determined by decreased tear-film stability and increased friction during blinking.

An eye on the dog as the scientist's best friend for translational research in ophthalmology: Focus on the ocular surface

Preclinical animal studies provide valuable opportunities to better understand human diseases and contribute to major advances in medicine. This review provides a comprehensive overview of ocular parameters in humans and selected animals, with a focus on the ocular surface, detailing species differences in ocular surface anatomy, physiology, tear film dynamics and tear film composition. We describe major pitfalls that tremendously limit the translational potential of traditional laboratory animals (i.e., rabbits, mice, and rats) in ophthalmic research, and highlight the benefits of integrating companion dogs with clinical analogues to human diseases into preclinical pharmacology studies. This One Health approach can help accelerate and improve the framework in which ophthalmic research is translated to the human clinic. Studies can be conducted in canine subjects with naturally occurring or noninvasively induced ocular surface disorders (e.g., dry eye disease, conjunctivitis), reviewed herein, and tear fluid can be easily retrieved from canine eyes for various bioanalytical purposes. In this review, we discuss common tear collection methods, including capillary tubes and Schirmer tear strips, and provide guidelines for tear sampling and extraction to improve the reliability of analyte quantification (drugs, proteins, others).

Impact of acute conjunctivitis on ocular surface homeostasis in dogs

OBJECTIVE

To investigate the effects of acute conjunctivitis on tear film characteristics and corneal sensitivity in dogs.

ANIMALS STUDIED

Eight female spayed Beagle dogs (1.5-2 years old, 7.5-10 kg).

PROCEDURES

On two consecutive days, one randomly selected eye in each dog received 1 or 375 mg/mL histamine solution to induce mild or severe conjunctivitis, while the contralateral eye served as control. Diagnostic tests were performed in the following order: fluorescein instillation and repeated tear collection over 20 minutes (to determine tear volume [TV] and turnover rate [TTR] by fluorophotometry), Schirmer tear test-1 (STT-1), tear ferning, corneal esthesiometry, and tear film breakup time (TFBUT).

RESULTS

Results are presented as median values for severe conjunctivitis, mild conjunctivitis, and control eyes. Eyes with severe conjunctivitis had significantly higher STT-1 (24, 19.5, 17.5 mm/min; P = .002) and significantly lower TFBUT (10.5, 13.5, 15.5 s; P = .002), but no changes were noted in corneal tactile sensation (2, 2.5, 2.5 cm) or tear ferning (grades 2, 2, 2.5). Severe conjunctivitis significantly increased TV by nearly 10-fold (631, 97, 65 µL) initially (reflex tearing), although basal TV returned rapidly (<5 minutes) in all eyes (46, 58, 48 µL). Finally, there was a nonsignificant trend for higher reflex TTR in the conjunctivitis vs control eyes (68, 58, 43%/min).

CONCLUSIONS

Experimentally induced conjunctivitis increases tear quantity and decreases tear quality in dogs, but has no impact on corneal sensitivity. Changes in tear film dynamics could affect ocular pharmacology (eg, precorneal retention time), although homeostasis of lacrimal volume and drainage is rapidly restored.

Amniotic membrane transplantation for managing dry eye and neurotrophic keratitis

Neurotrophic keratitis (NK), a degenerative disease caused by damage to the trigeminal nerve, abolishes both tearing and blinking reflexes, thus causing the most severe forms of dry eye disease (DED). Conversely, the increasing severity of DED also leads to progressive loss of corneal nerve density, potentially resulting in NK. Both diseases manifest the same spectrum of corneal pathologies including inflammation and corneal epithelial keratitis, which can progress into vision-threatening epithelial defect and stromal ulceration. This review summarizes the current literature regarding outcomes following sutured and sutureless cryopreserved amniotic membrane (AM) in treating DED as well as epithelial defects and corneal ulcers due to underlying NK. These studies collectively support the safety and effectiveness of cryopreserved AM in restoring corneal epithelial health, improving visual acuity in eyes with NK and DED, and alleviating symptomatic DED. Future randomized controlled trials are warranted to validate the above findings and determine whether such clinical efficacy lies in promoting corneal nerve regeneration.

Fourier-Domain OCT Imaging of the Ocular Surface and Tear Film Dynamics: A Review of the State of the Art and an Integrative Model of the Tear Behavior During the Inter-Blink Period and Visual Fixation

In the last few decades, the ocular surface and the tear film have been noninvasively investigated in vivo, in a three-dimensional, high resolution, and real-time mode, by optical coherence tomography (OCT). Recently, OCT technology has made great strides in improving the acquisition speed and image resolution, thus increasing its impact in daily clinical practice and in the research setting. All these results have been achieved because of a transition from traditional time-domain (TD) to Fourier-domain (FD) technology. FD-OCT devices include a spectrometer in the receiver that analyzes the spectrum of reflected light on the retina or ocular surface and transforms it into information about the depth of the structures according to the Fourier principle. In this review, we summarize and provide the state-of-the-art in FD-OCT imaging of the ocular surface system, addressing specific aspects such as tear film dynamics and epithelial changes under physiologic and pathologic conditions. A theory on the dynamic nature of the tear film has been developed to explain the variations within the individual compartments. Moreover, an integrative model of tear film behavior during the inter-blink period and visual fixation is proposed.

Comparison of cytotoxicities and anti-allergic effects of topical ocular dual-action anti-allergic agents

Background

To investigate the cytotoxicities of the topical ocular dual-action anti-allergic agents (alcaftadine 0.25%, bepotastine besilate 1.5%, and olopatadine HCL 0.1%) on human corneal epithelial cells (HCECs) and their anti-allergic effects on cultured conjunctival epithelial cells.

Methods

A Methylthiazolyltetrazolium(MTT)-based calorimetric assay was used to assess cytotoxicities using HCECs at concentrations of 10, 20 or 30% for exposure durations of 30 min, 1 h, 2 h, 12 h or 24 h. Cellular morphologies were evaluated by inverted phase-contrast and electron microscopy. Wound widths were measured 2 h, 18 h, or 24 h after confluent HCECs monolayers were scratched. Realtime PCR was used to quantify anti-allergic effects on cultured human conjunctival cells, in which allergic reactions were induced by treating them with Aspergillus antigen.

Results

Cell viabilities decreased in time- and concentration-dependent manners. Cells were detached from dishes and showed microvilli loss, cytoplasmic vacuoles, and nuclear condensation when exposed to antiallergic agents; alcaftadine was found to be least cytotoxic. Alcaftadine treated HCECs monolayers showed the best wound healing followed by bepotastine and olopatadine (p < 0.0001). All agents significantly reduced the gene expressions of allergic cytokines (IL-5, IL-25, eotaxin, thymus and activation-regulated chemokine, and thymic stromal lymphopoietin) and alcaftadine had the greatest effect (p < 0.0001 in all cases).

Conclusions

Alcaftadine seems to have less side effects and better therapeutic effects than the other two anti-allergic agents tested. It may be more beneficial to use less toxic agents for patients with ocular surface risk factors or presumed symptoms of toxicity.

Floppy eyelid syndrome: A comprehensive review

Floppy eyelid syndrome (FES) is defined as eyelid hyperlaxity with reactive palpebral conjunctivitis. It is a common condition that can be associated with significant ocular irritation. FES presents with easily everted eyelids and chronic papillary conjunctivitis in the upper eyelids. It is frequently associated with ocular and systemic diseases, notably keratoconus and obstructive sleep apnea, respectively. This comprehensive review describes the epidemiology, pathological changes, proposed pathogenesis, clinical manifestations, and a variety of treatment options for this condition. Conservative treatment of FES includes aggressive lubrication, nighttime eye shield, and avoiding sleeping on the affected eye. Patients with FES and obstructive sleep apnea may have an improvement in their ocular signs and symptoms after long-term therapy with continuous positive airway pressure. In refractory cases, a corrective surgery that addresses the eyelid laxity can result in significant improvement. All patients with ocular irritation should be evaluated for the presence of FES.

Evaluation of the tear clearance rate by dacryoscintigraphy in patients with obstructive meibomian gland dysfunction

PURPOSE

To measure tear clearance values in patients with meibomian gland dysfunction (MGD) with a dynamic nuclear medicine method, namely, dacryoscintigraphy (DSCI).

METHODS

Twenty-four MGD patients and 24 healthy volunteers were examined. During DSCI one drop of a solution with 100 MBq/mL^99mTc sodium pertechnetate was instilled with a micropipette into the lacrimal lake of both eyes. Measurements were performed according to a dynamic data acquisition protocol, which resulted in summed DSCI images. Data were also evaluated separately in special regions of interest (ROI), and consecutive time activity curves were created. Tear clearance (T½) values were calculated based on the activity curves. In addition, tear osmolarity measurements, tear breakup time (tBUT), and Schirmer I (ST_I) tests were performed prior to DSCI examination.

RESULTS

The T½ values were 29.91 ± 11.61 min in MGD patients and 6.26 ± 1.5 min in healthy controls. Tear osmolarity parameters were 308 ± 9.41 mOsm/L and 288.9 ± 6.4 mOsm/L, tBUT values were 5.54 ± 2.73 s and 11.4 ± 2.7 s, while the ST_I test values were 6.17 ± 2.78 mm and 13.58 ± 3.8 mm, respectively. The differences were significant (p < 0.01) in all cases.

CONCLUSIONS

Although the MGD patients' lacrimal drainage systems were patent their tear clearance values were significantly higher than those of healthy volunteers, which may be caused by decreased drainage of tears from the eyes towards the nasal cavity. The understanding of new features regarding the altered physico-chemical characteristics of MGD tears has been augmented by the results of this study.

Photography-based method for assessing fluorescein clearance test in dogs

BACKGROUND

The fluorescein clearance test (FCT) provides insight into the tear film dynamics. The purpose of this study was to describe an inexpensive and practical method for assessing FCT in dogs, using photography and software analysis, and to assess the retention time of 1 vs. 2 eye drops on the canine ocular surface.

METHODS

(i) In vivo - Eight healthy German Shepherd dogs were recruited. Following topical anesthesia with 0.5% proxymetacaine, each eye sequentially received (1 week apart) either 1 drop (35 μL) or 2 drops (70 μL) of 0.5% fluorescein. A Schirmer strip was inserted in the ventral conjunctival fornix for 10 s at the following times: each 10 min for 100 min, 24 h, 48 h and 72 h. (ii) In vitro - Schirmer strips were placed for 10 s in contact with microplate wells containing 1 or 2 drops of 0.5% fluorescein. In both experiments, the fluorescein-impregnated Schirmer strips were immediately imaged, and the area and intensity of fluorescein uptake were analyzed with ImageJ software. For the in vitro experiment, images were evaluated by the same examiner (repeatability) or two examiners (reproducibility).

RESULTS

Photography-based FCT was easy to perform and showed high repeatability and reproducibility (coefficients of variation ≤2.75%). In vivo, the area and intensity of fluorescein uptake on Schirmer strips were significantly greater at 30 min and 40 min post- fluorescein instillation in the 2 drops vs. 1 drop groups (p ≤ 0.044). Compared to baseline, the residual fluorescein uptake on Schirmer strips was < 5% at 60 min and 90 min in the 1 drop and 2 drops groups, respectively.

CONCLUSIONS

Photography-based FCT is a practical and reliable diagnostic tool with various clinical and research applications in veterinary medicine. Instillation of two drops provided greater amount and longer retention on the anesthetized canine ocular surface than a single drop. Fluorescein clearance time of a single drop in dolichocephalic dogs is 60 min.

Resolution of recalcitrant chronic papillary conjunctivitis associated with epiphora following punctoplasty and lacrimal stenting

OBJECTIVE

To assess the use of lacrimal stenting for chronic papillary conjunctivitis associated with epiphora in young adults with little or no atopic background.

METHODS

A retrospective interventional case series of 21 consecutive patients (36 eyes) treated for epiphora and chronic papillary conjunctivitis at a tertiary university-affiliated medical center between January 2014 and August 2015 by the same oculoplastic surgeon (I.A). Data were collected by retrospective file review. Patients with a history of ocular disease were excluded from the study. Treatment modalities included lacrimal stenting, punctoplasty, and conservative topical medication. The main outcome measure was post-treatment presence of epiphora and conjunctivitis.

RESULTS

Mean patient age was 40 ± 11 years; 86% of patients were female. Fifteen (72%) had bilateral disease. Mean follow-up time was 3.9 ± 1.7 months. Delayed tear clearance as well as a patent lacrimal apparatus were noted in all eyes. No apparent cause of the symptoms was found in any of the eyes. In 12 of the 13 patients (92%) who underwent tube or stent placement, the conjunctivitis and epiphora resolved. In the remainder, symptoms resolved bilaterally in only 1 of 4 patients (25%) who underwent punctoplasty and in only 1 of 4 patients (25%) treated conservatively.

CONCLUSION

Recalcitrant papillary conjunctivitis improves following nasolacrimal stenting. Further studies are needed using a prospective controlled design and longer follow-up time.

Changes in ocular surface status after phacoemulsification in patients with senile cataract

AIM

To evaluate the signs and symptoms of dry eye after phacoemulsification; effects on the status of ocular surface using impression cytology; and associated risk factors.

METHODS

Prospective study included 50 eyes (50 patients) with no dry eye signs or symptoms, who underwent clear corneal phacoemulsification for senile cataract. Dry eye indices used included Ocular Surface Disease Index scoring, Schirmer I test, tear break up time, tear meniscus height, corneal fluorescein staining, lissamine green staining and goblet cell density (GCD) with the help of impression cytology. Primary outcome measures included post-operative changes in the dry eye indices. Secondary outcome measures included correlation of the dry eye signs and symptoms with various risk factors.

RESULTS

Aggravation of both the signs and symptoms of dry eye were noted in immediate post-operative period. The sharp deterioration was followed by a recovering trend towards the end of sixth week. A decrease in GCD was also noted. Risk factors for deterioration include age, duration of exposure to microscope light and effective phacoemulsification time. Diabetic status, socio-economic status and site of incision did not have any effect on dry eye status.

CONCLUSION

There is a transient deterioration of "dry eye" status post-phacoemulsification. The patients should be carefully counselled about the evanescent nature of the disease. Incision can be given at the site of high corneal curvature to neutralize astigmatism without any fear of inducing dry eye. Minimum light exposure and ultrasound energy should be used during the surgery.

[Corneal transparency: anatomical basis and evaluation methods]

Being just a relatively small part of the fibrous tunic of the eyeball, the cornea is, nevertheless, unique in terms of the variety of its functions. Because the cornea differs significantly from other protective frames in its structure, it provides the possibility of light transmission and strong refraction that largely contributes to the total refraction of the eye. The development of ophthalmology is impossible without improving methods of adequate anatomical and functional assessment of the eye not only as a whole, but also as a collection of interacting structures.In this regard, examination methods of the cornea have undergone significant advances in recent years. So far, the level of corneal transparency has been judged by biomicroscopy findings or indirect characteristics (thickness, structure, etc.). Confocal microscopy of the cornea and wave-based examinations involving one of the available laser interferometers (OCT or HRT) are also used. However, the data obtained with these methods resembles that of layer-specific reflectometry, i.e. the magnitude of directed reflection of the light beam from corneal corpuscles, which does not completely agree with the classical idea of transparency.

Conjunctivochalasis: a systematic review

Conjunctivochalasis (CCH) is a conjunctival condition characterized by loose, redundant conjunctival folds, most typically in the inferior bulbar conjunctiva of both eyes. Although CCH is a common cause of ocular irritation and discomfort, especially in the elderly, it is often overlooked in clinical practice. CCH may be associated with various ocular and nonocular conditions; however, the most important risk factor is aging. Although often asymptomatic, CCH may cause symptoms related to tear film instability and/or delayed tear clearance. Pathogenesis of CCH remains largely unknown but may involve different elements such as aged conjunctiva, unstable tear film, mechanical friction, ocular surface inflammation, and delayed tear clearance. Contradictory results have been reported on histopathologic changes in CCH, with some studies showing a normal microscopic structure. For symptomatic CCH, medical treatment may include lubrication and anti-inflammatory medications. For symptomatic patients who fail to respond to medical treatment, a surgical procedure may be considered. Although various surgical procedures have been used for CCH, more often, it consists of conjunctival cauterization or excision of the redundant conjunctiva, with or without amniotic membrane transplantation.

Relevance of Lipid-Based Products in the Management of Dry Eye Disease

Components of the ocular surface synergistically contribute to maintaining and protecting a smooth refractive layer to facilitate the optimal transmission of light. At the air-water interface, the tear film lipid layer (TFLL), a mixture of lipids and proteins, plays a key role in tear surface tension and is important for the physiological hydration of the ocular surface and for ocular homeostasis. Alterations in tear fluid rheology, differences in lipid composition, or downregulation of specific tear proteins are found in most types of ocular surface disease, including dry eye disease (DED). Artificial tears have long been a first line of treatment in DED and aim to replace or supplement tears. More recently, lipid-containing eye drops have been developed to more closely mimic the combination of aqueous and lipid layers of the TFLL. Over the last 2 decades, our understanding of the nature and importance of lipids in the tear film in health and disease has increased substantially. The aim of this article is to provide a brief overview of our current understanding of tear film properties and review the effectiveness of lipid-based products in the treatment of DED. Liposome lid sprays, emulsion eye drops, and other lipid-containing formulations are discussed.

TFOS DEWS II iatrogenic report

Dry eye can be caused by a variety of iatrogenic interventions. The increasing number of patients looking for eye care or cosmetic procedures involving the eyes, together with a better understanding of the pathophysiological mechanisms of dry eye disease (DED), have led to the need for a specific report about iatrogenic dry eye within the TFOS DEWS II. Topical medications can cause DED due to their allergic, toxic and immuno-inflammatory effects on the ocular surface. Preservatives, such as benzalkonium chloride, may further aggravate DED. A variety of systemic drugs can also induce DED secondary to multiple mechanisms. Moreover, the use of contact lens induces or is associated with DED. However, one of the most emblematic situations is DED caused by surgical procedures such as corneal refractive surgery as in laser-assisted in situ keratomileusis (LASIK) and keratoplasty due to mechanisms intrinsic to the procedure (i.e. corneal nerve cutting) or even by the use of postoperative topical drugs. Cataract surgery, lid surgeries, botulinum toxin application and cosmetic procedures are also considered risk factors to iatrogenic DED, which can cause patient dissatisfaction, visual disturbance and poor surgical outcomes. This report also presents future directions to address iatrogenic DED, including the need for more in-depth epidemiological studies about the risk factors, development of less toxic medications and preservatives, as well as new techniques for less invasive eye surgeries. Novel research into detection of early dry eye prior to surgeries, efforts to establish appropriate therapeutics and a greater attempt to regulate and oversee medications, preservatives and procedures should be considered.

Restoration of Fornix Tear Reservoir in Conjunctivochalasis With Fornix Reconstruction

PURPOSE

To determine whether conjunctivochalasis (CCh) obliterates the fornix tear reservoir and to discern whether there is concomitant aqueous tear deficiency (ATD) dry eye.

METHODS

Retrospective review of 18 eyes of 12 patients with CCh and ATD (CCh + ATD) and 18 eyes of 13 patients with CCh without ATD (CCh - ATD). Changes were compared before and after fornix reconstruction regarding symptoms, basal tear volumes, use of medications, conjunctival inflammation, and corneal staining.

RESULTS

Fornix reconstruction with conjunctival recession and amniotic membrane transplantation effectively restored the fornix tear reservoir as evidenced by a significant increase of the basal tear volume in both CCh - ATD and CCh + ATD groups. Multivariate regression analysis confirmed that such improvement was significantly correlated with symptomatic resolution (r = 1, P < 0.001), which was also accompanied by significant resolution of corneal staining, conjunctival inflammation, and reduction of topical medications. Intriguingly, the prior diagnosis of ATD was no longer existent in 10 of the 18 eyes (56%) with CCh + ATD suggesting that ATD could be secondary to obliteration of the fornix tear reservoir by CCh.

CONCLUSIONS

Obliteration of the fornix tear reservoir is a common pathogenic process regardless of whether CCh is associated with ATD dry eye. Restoration of the tear reservoir by fornix reconstruction with conjunctival recession and amniotic membrane transplantation results in significant resolution of symptoms and signs associated with ATD that is secondary to CCh and helps identify genuine ATD dry eye that is independent of CCh.

Mucosal immune tolerance at the ocular surface in health and disease

The ocular surface is constantly exposed to environmental irritants, allergens and pathogens, against which it can mount a prompt immune response to preserve its integrity. But to avoid unnecessary inflammation, the ocular surface's mucosal immune system must also discriminate between harmless and potentially dangerous antigens, a seemingly complicated task. Despite its unique features, the ocular surface is a mucosal lining, and as such, it shares some homeostatic and pathophysiological mechanisms with other mucosal surfaces. The purpose of this review is to explore the mucosal homeostatic immune function of the ocular surface in both the healthy and diseased states, with a special focus on mucosal immunology concepts. The information discussed in this review has been retrieved by PubMed searches for literature published from January 1981 to October 2016.

Evaluation of the Effects of Conjunctivochalasis Excision on Tear Stability and Contrast Sensitivity

Conjunctivochalasis (CCh) disrupts tear flow and damages tear film stability. This study sought to evaluate the tear stability and contrast sensitivity of patients with CCh on whom CCh excision was performed. The study included 39 eyes from 39 patients; all patients had eyes with grade 2 or 3 CCh, underwent CCh excision, and were evaluated before and three months after the surgery. The evaluated variables included the ocular surface disease index (OSDI), the tear break-up time (TBUT), corneal fluorescein staining, corneal surface irregularity, Schirmer’s I test, the tear meniscus area (TMA), and contrast sensitivity. A follow-up of three months was achieved in 36 eyes for 36 patients. All parameters improved significantly after surgery (p < 0.05), except Schirmer’s I test, thus suggesting that CCh excision is an effective method for reconstructing the lower tear meniscus and improving both tear film stability and corneal surface irregularity. The results further demonstrated a simultaneous increase in contrast sensitivity after surgery.

Assessment of Tear Film Quality among Smokers Using Tear Ferning Patterns

Purpose. To investigate the effect of cigarette smoking on the ocular tear film. Methods. Thirty healthy young male cigarette smokers (20–38 years old) and 30 healthy age matched nonsmokers were enrolled in the study. McMonnies questionnaire, slit lamp, and PRT test were used to screen the subjects. Tear samples were collected from the right eyes and tear ferning patterns were observed and graded. Results. The mean MacMonnies scores and TF grades were significantly higher in the smoker subjects (mean ± SD = 9.83 ± 5.22 and 0.96 ± 0.54, resp.) compared to nonsmokers (mean ± SD = 5.96 ± 3.06 and 0.41 ± 0.38, resp.). The mean values obtained from PRT and TBUT tests were 22.23 ± 6.35 mm and 12.17 ± 3.81 s for smokers and 22.16 ± 5.63 mm and 14.13 ± 2.62 s for nonsmokers, respectively. Strong correlations were found between MacMonnies scores and both PRT (r = 0.596) and TF (r = 0.516). There was statistically significant difference in TF grades (p = 0.00), TBUT (p = 0.036) and McMonnies (p = 0.02) between smokers and nonsmokers. Conclusion. Cigarette smoking could have a significant effect on the tear film quality of the eye.

Morselized Amniotic Membrane Tissue for Refractory Corneal Epithelial Defects in Cicatricial Ocular Surface Diseases

Purpose

To evaluate the clinical efficacy of morselized amniotic membrane and umbilical cord tissue (MAU) in treating refractory corneal epithelial defect in ocular cicatricial diseases.

Methods

Retrospective review of four patients with ocular cicatricial diseases treated with topical MAU for corneal epithelial defects refractory to conventional treatments including topical lubricants, autologous serum, bandage contact lens, and tarsorraphy. Their symptoms, corneal staining, conjunctival inflammation, and visual acuity were compared before and after treatment.

Results

After topical application of MAU twice daily, two patients demonstrated rapid corneal epithelialization with prompt visual acuity improvement at the first day. All patients showed corneal epithelialization in 7.3 ± 2.6 days accompanied by a significant relief of symptoms, reduction of ocular surface inflammation, and improvement of visual acuity.

Conclusion

This pilot study suggests topical MAU can be developed into a novel treatment for treating refractory corneal epithelial defects.

Translational Relevance

Topical MAU can be an effective novel treatment for refractory corneal epithelial defects.

Repeatability and Diurnal Variation of Tear Ferning Test

OBJECTIVES

To investigate tear ferning (TF) test repeatability between sessions by observing changes in the tear fern pattern during the day.

METHODS

Twenty-three healthy young adults (15 men and 8 women), ranging in age from 20 to 32 years (mean ± SD: 22.9 ± 3.3 years) without signs or symptoms of dry eye disease, ocular disease, or contact lens wear were enrolled in the study. Schirmer I, tear break-up time (TBUT) test, and McMonnies questionnaire were used to screen volunteers. Schirmer I and TBUT tests were applied to both eyes in each subject. Four samples of tear fluid were collected from the right eye of each subject using glass capillaries at set intervals during a single day (9 AM, 11 AM, 2 PM, and 4 PM). The TF patterns obtained from samples were classified according to the Masmali TF grading scale to increments of 0.1.

RESULTS

The median values obtained from the McMonnies, Schirmer, and TBUT tests were 4.0 ± 2.0, 30.0 ± 7.0 mm (OD), and 16.0 ± 10.0 sec (OD), respectively. There were no statistically significant differences between the TF grades for tear samples collected at different times of the day (Wilks' Lambda, P = 0.351). The majority (84.8%) of TF grades was between 0.0 and 1.5; the remaining 15.2% of subjects had TF between grades 1.6 and 1.9. The overall mean grade for the TF was 1.1 ± 0.3. There were small insignificant correlations between TF grades and the McMonnies questionnaire (r = 0.1.30) and TBUT (r = 0.248) and a negligible correlation with Schirmer test (r = -0.046).

CONCLUSIONS

The results found no significant differences within the TF for tear samples collected at different times of the day, suggesting that there is little diurnal variation evident.

Dry Eye Profiles in Patients with a Positive Elevated Surface Matrix Metalloproteinase 9 Point-of-Care Test Versus Negative Patients

PURPOSE

To compare dry eye (DE) symptoms and signs in subjects who tested positive versus those who tested negative for ocular surface matrix metalloproteinase 9 (MMP-9) using the InflammaDry point-of-care test (RPS, Sarasota, FL).

METHODS

In this cross-sectional study, individuals seen in the Miami Veterans Affairs eye clinic with DE symptoms, as evidenced by DE questionnaire 5 (DEQ5) ≥6, were given standardized questionnaires to assess DE symptoms and ocular and non-ocular pain complaints. Also, a complete evaluation was conducted to measure ocular surface signs of DE. MMP-9 testing was performed using the InflammaDry once in each eye, per the manufacturer's instructions. The main outcome measure was a comparison of DE symptoms and signs in MMP-9 positive versus negative subjects.

RESULTS

Of 128 subjects, 50 (39%) were positive for MMP-9 for InflammaDry testing in either eye. No statistically significant differences in mental health indices, DE symptoms, or ocular surface signs were seen in subjects based on MMP-9 status.

CONCLUSION

In our population, there was no difference in the DE profile by both symptoms and signs between those testing positive versus negative for MMP-9 on the ocular surface. This suggests that clinical exam alone cannot predict patients with clinically significant inflammation.

Potential candidate cells for constructing tissue-engineered lacrimal duct epithelium: a histological and cytological study in rabbits

OBJECTIVE

Injury and deficiency of the lacrimal duct epithelium (LDE) can lead to a variety of lacrimal diseases. The purpose of this study was to characterize potential candidate cells for constructing a tissue-engineered LDE.

METHODS

Different areas of the conjunctiva and lacrimal duct tissue were removed from male adult New Zealand white rabbits for histological evaluation. Hematoxylin and eosin staining and immunohistochemical staining of cytokeratin AE1+AE3, cytokeratin 4, Ki-67, and MUC5AC were observed by light microscopy. The surface morphologies of different epithelial tissues and cellular structures were examined using field-emission scanning electron microscopy and transmission electron microscopy. Epithelial cells were isolated from tissues and identified by specific markers. In vitro, proliferative ability and Western blot analyses of the proliferating cell nuclear antigen (PCNA) of different epithelial cells cultured in identical environments were investigated and compared.

RESULTS

Histologically, the epithelial specific markers, cytokeratin AE1+AE3 and cytokeratin 4, were expressed in the conjunctiva epithelium and the LDE. Notably, highly proliferative cells stained with Ki-67 were concentrated under the epithelium in a dome structure of the posterior palpebral conjunctiva. Differentiated goblet cells were also found to a lesser extent in this region. Primary palpebral and fornical conjunctival epithelial cells (PFCECs), bulbar conjunctival epithelial cells (BCECs), and lacrimal duct epithelial cells (LDECs) were successfully separated from tissues. In vitro, rabbit PFCECs and LDECs grew faster and expressed more PCNA than BCECs.

CONCLUSIONS

PFCECs are anatomically similar to LDECs. They also have similar morphological characteristics, immune phenotypes, and proliferation features. PFCECs are therefore potential candidate cells to replace LDECs in tissue engineering to treat lacrimal duct diseases.

Topical Fluorometholone Protects the Ocular Surface of Dry Eye Patients from Desiccating Stress: A Randomized Controlled Clinical Trial

PURPOSE

To assess the efficacy of topical 0.1% fluorometholone in dry eye disease (DED) patients for ameliorating the worsening of the ocular surface when exposed to adverse environments.

DESIGN

Single-center, double-masked, randomized, vehicle-controlled clinical trial.

PARTICIPANTS

Forty-one patients showing moderate to severe DED.

METHODS

Patients randomly received 1 drop 4 times daily of either topical 0.1% fluorometholone (FML group) or topical polyvinyl alcohol (PA group) for 22 days. Corneal and conjunctival staining, conjunctival hyperemia, tear film breakup time (TBUT), tear osmolarity, and the Symptom Assessment in Dry Eye (SANDE) questionnaire scores were determined at baseline. Variables were reassessed on day 21 before and after undergoing a 2-hour controlled adverse environment exposure and again on day 22.

MAIN OUTCOMES MEASURES

Percentage of patients showing an increase 1 point or more in corneal staining and a reduction of 2 points or more (0-10 scale) in SANDE score, after the controlled adverse environment exposure and 24 hours later.

RESULTS

After 21 days of treatment, the FML group showed greater improvements in corneal and conjunctival staining, hyperemia, and TBUT than the PA group (P≤0.03). After the adverse exposure, the percentage of patients having a 1-grade or more increase in corneal staining was significantly (P = 0.03) higher in the PA group (63.1% vs. 23.8%, respectively). Additionally, the FML group showed no significant changes in corneal staining (mean, 0.86; 95% confidence interval [CI], 0.47-1.25; vs. mean, 1.05; 95% CI, 0.59-1.51, for visit 2 and 3, respectively), conjunctival staining (mean, 0.95; 95% CI, 0.54-1.37 vs. mean, 1.19; 95% CI, 0.75-1.63), and hyperemia (mean, 0.71; 95% CI, 0.41-1.02 vs. 1.14; 95% CI, 0.71-1.58) after the exposure, whereas for the PA group, there was significant worsening (P≤0.009) in these variables (corneal staining: mean, 1.95; 95% CI, 1.57-2.33 vs. mean, 2.58; 95% CI, 2.17-2.98; conjunctival staining: mean, 1.68; 95% CI, 1.29-2.08 vs. mean, 2.47; 95% CI, 2.07-2.88; hyperemia: mean, 1.95; 95% CI, 1.63-2.26 vs. mean, 2.84; 95% CI, 2.62-3.07).

CONCLUSIONS

Three-week topical 0.1% fluorometholone therapy is effective not only in reducing ocular surface signs in DED patients, but also especially in preventing exacerbation caused by exposure to a desiccating stress.

Human Tear Serotonin Levels Correlate with Symptoms and Signs of Dry Eye

PURPOSE

Serotonin, a neurotransmitter known to be involved in nociceptor sensitization, is present in human tears. The purpose of this study was to correlate tear serotonin levels, as a marker of nociceptor sensitization, to facets of dry eye (DE), including symptoms and signs.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 62 patients with normal eyelid and corneal anatomy were prospectively recruited from a Veterans Administration Ophthalmology Clinic over 11 months.

METHODS

Dry eye symptoms (Ocular Surface Disease Index [OSDI]), signs (tear break-up time [TBUT], corneal staining, and Schirmer's score), and clinical descriptors of neuropathic ocular pain (NOP) (sensitivity to light or sensitivity to wind) were assessed. For tear analysis, each patient's tears were collected after instilling 50 μl of sterile saline to the lower cul-de-sac of each eye and using capillary action microcaps to collect the ocular wash. Tear serotonin levels were measured using enzyme-linked immunosorbent assay.

MAIN OUTCOME MEASURES

Correlations between tear serotonin concentrations and DE symptoms and signs.

RESULTS

The mean age of the population was 61±14 years, and 84% (n = 52) of the patients were male. Serotonin concentrations negatively correlated with Schirmer's scores (r = -0.28; P = 0.02) but did not correlate with other DE parameters, such as OSDI scores, sensitivity to light or wind, TBUT, and staining. According to our hypothesis, we divided patients into groups based on both DE symptoms and aqueous tear production; serotonin concentrations were significantly higher in DE group 1 (OSDI ≥6 and Schirmer's <8) compared with both DE group 2 (OSDI ≥6 and Schirmer's ≥8) and controls (OSDI <6 and Schirmer's ≥8). Patients in DE group 2 more frequently reported sensitivity to light (64%) and wind (67%) compared with DE group 1 (40% and 60%, respectively) and controls (8% and 17%, respectively).

CONCLUSIONS

Patients with DE symptoms and aqueous tear deficiency had higher tear serotonin levels compared with those with DE symptoms but normal tear production and those without DE symptoms.

Efficacy and Safety of Topical 0.05% Cyclosporine Eye Drops in the Treatment of Dry Eye Syndrome: A Systematic Review and Meta-analysis

A systematic review was performed to evaluate the safety and efficacy of topical 0.05% cyclosporine in treating patients with dry eye syndrome (DES). Twelve qualified randomized-controlled trials incorporating 1367 patients were analyzed. In comparison to controls, patients who were on topical 0.05% cyclosporine eye drops had lower Ocular Surface Disease Index scores (mean difference [MD]=4.10, 95% CI: 0.25-7.96, P=.04), longer tear film breakup time (MD=2.30 seconds, 95% CI: 0.75-3.86, P=.004), improved Schirmer I scores (MD=2.77 mm/5min, 95% CI: 1.63-3.91, P=.00001), reduced corneal fluorescein staining (standardized mean difference [SMD]=0.61, 95% CI: 0.07-1.15, P=.03), and higher goblet cell densities (SMD=1.68, 95% CI: 0.54-2.81, P=.004). However, there were more adverse effects in the cyclosporine patient group (odds ratio=1.64, 95% CI: 1.17-2.30, P=.004). Topical 0.05% cyclosporine eye drops twice daily significantly improved both the objective and subjective outcomes in DES patients. The study limitations in the clinical, methodological and statistical heterogeneities are discussed.

Diagnosis of dry eye disease and emerging technologies

Dry eye is one of the most commonly encountered problems in ophthalmology. Signs can include punctate epithelial erosions, hyperemia, low tear lakes, rapid tear break-up time, and meibomian gland disease. Current methods of diagnosis include a slit-lamp examination with and without different stains, including fluorescein, rose bengal, and lissamine green. Other methods are the Schirmer test, tear function index, tear break-up time, and functional visual acuity. Emerging technologies include meniscometry, optical coherence tomography, tear film stability analysis, interferometry, tear osmolarity, the tear film normalization test, ocular surface thermography, and tear biomarkers. Patient-specific considerations involve relevant history of autoimmune disease, refractive surgery or use of oral medications, and allergies or rosacea. Other patient considerations include clinical examination for lid margin disease and presence of lagophthalmos or blink abnormalities. Given a complex presentation and a variety of signs and symptoms, it would be beneficial if there was an inexpensive, readily available, and reproducible diagnostic test for dry eye.

Changes in cytokines in tears after endoscopic endonasal dacryocystorhinostomy for primary acquired nasolacrimal duct obstruction

PURPOSE

We attempted to compare the cytokine composition of tears between primary acquired nasolacrimal duct (NLD) obstruction and normal controls. We investigated the changes in cytokines in tears after endoscopic endonasal dacryocystorhinostomy (DCR).

PATIENTS AND METHODS

Eighteen patients underwent endonasal DCR, with seven patients undergoing bilateral DCR, resulting in twenty-five DCRs in total. Eleven contralateral un-operated eyes were used as normal controls. Silicone stents were removed 3 months after surgery. Tear samples were collected from all eyes before surgery, and at 1 month, 2 months, 3 months, and 4 months after surgery. The level of interleukin (IL)-1β, IL-2, IL-6, IL-10, transforming growth factor (TGF)-β2, fibroblast growth factor (FGF)-2, and vascular endothelial growth factor (VEGF) in the tears was measured.

RESULTS

The concentrations of IL-2, IL-6, IL-10, VEGF, and FGF-2 were significantly higher in eyes with NLD obstruction than controls before surgery (P=0.006, 0.018, 0.002, 0.048, and 0.039, respectively). Most inflammatory cytokines (IL-1β, IL-2, IL-6, VEGF, and FGF-2) were higher in the tears of the DCR group compared with the controls during the postoperative follow-up, but then rapidly decreased to the level of the controls after removal of the silicone stent. The recurred eyes showed a higher level of TGF-β2 and FGF-2 in tears compared with the eyes that showed good surgical results (P<0.005 and <0.005, respectively).

CONCLUSION

The tear levels of inflammatory cytokines were higher in eyes with NLD obstruction than controls. The changes in cytokine level during the postoperative period showed the importance of cytokine analysis in understanding wound healing after DCR.