Therapeutical approach to dry eye syndrome

Recent Developments About the Pathogenesis of Dry Eye Disease: Based on Immune Inflammatory Mechanisms

Dry eye disease is a common and frequently occurring ophthalmology with complex and diverse causes, and its incidence is on the upward trend. The pathogenesis of DED is still completely clear. However, the immune response based on inflammation has been recognized as the core basis of this disease. In this review, we will systematically review the previous research on the treatment of DED in immune inflammation, analyze the latest views and research hotspots, and provide reference for the prevention and treatment of DED.

Lacrimal gland development: From signaling interactions to regenerative medicine

The lacrimal gland plays a pivotal role in keeping the ocular surface lubricated, and protecting it from environmental exposure and insult. Dysfunction of the lacrimal gland results in deficiency of the aqueous component of the tear film, which can cause dryness of the ocular surface, also known as the aqueous-deficient dry eye disease. Left untreated, this disease can lead to significant morbidity, including frequent eye infections, corneal ulcerations, and vision loss. Current therapies do not treat the underlying deficiency of the lacrimal gland, but merely provide symptomatic relief. To develop more sustainable and physiological therapies, such as in vivo lacrimal gland regeneration or bioengineered lacrimal gland implants, a thorough understanding of lacrimal gland development at the molecular level is of paramount importance. Based on the structural and functional similarities between rodent and human eye development, extensive studies have been undertaken to investigate the signaling and transcriptional mechanisms of lacrimal gland development using mouse as a model system. In this review, we describe the current understanding of the extrinsic signaling interactions and the intrinsic transcriptional network governing lacrimal gland morphogenesis, as well as recent advances in the field of regenerative medicine aimed at treating dry eye disease. Developmental Dynamics 246:970-980, 2017. © 2017 Wiley Periodicals, Inc.

A Randomized Multicenter Study Comparing 0.1%, 0.15%, and 0.3% Sodium Hyaluronate with 0.05% Cyclosporine in the Treatment of Dry Eye

Purpose: To investigate the efficacy of 0.1%, 0.15%, and 0.3% sodium hyaluronate (SH) artificial tears compared with 0.05% cyclosporine (CS) ophthalmic solution for the treatment of dry eye.

Methods: One hundred seventy-six patients were recruited and randomized to receive of 0.1%, 0.15%, and 0.3% SH and 0.05% CS. There was a primary end point which is the changes in the fluorescein corneal staining (FCS) score to determine noninferiority of 0.1%, 0.15%, and 0.3% SH. Secondary objective end points were lissamine green conjunctival staining (LGCS) scores, Schirmer test, and tear film break-up time (TBUT). Secondary subjective end point was ocular surface disease index (OSDI) score. These were evaluated before treatment and 6 and 12 weeks after start of treatment.

Results: In the primary analysis, the mean change from baseline in FCS scores verified noninferiority of 0.1% and 0.15% SH to 0.05% CS and also indicated significant improvement of all groups (P < 0.05). Values for TBUT, LGCS scores, and OSDI scores showed significant improvements in all groups (P < 0.05), although no significant intergroup difference was shown. However, Schirmer test scores in the 0.15% SH group showed a significant tendency for better improvement at week 12 compared with the other groups (P < 0.05). No serious adverse events were observed.

Conclusions: Administration of 0.1%, 0.15%, and 0.3% SH was effective in improving both the objective signs and subjective symptoms of dry eye. Those findings, in addition to the well-tolerated profile of 0.1%, 0.15%, and 0.3% SH, show that it is effective therapeutic method for dry eye.

A randomised, parallel-group comparison study of diquafosol ophthalmic solution in patients with dry eye in China and Singapore

AIMS

To compare the efficacy and safety of 3% diquafosol ophthalmic solution with those of 0.1% sodium hyaluronate ophthalmic solution in patients with dry eye in China and Singapore.

METHODS

A total of 497 patients with dry eye (Schirmer's test, 5 mm; fluorescein and RB score, 3 points) from China and Singapore were randomised to receive either diquafosol ophthalmic solution (diquafosol) or sodium hyaluronate ophthalmic solution (HA) at 1:1 ratio. The fluorescein staining scores and rose bengal (RB) subjective symptom scores and tear film breakup time were evaluated before treatment and 2 and 4 weeks after start of treatment.

RESULTS

In the diquafosol group, changes in fluorescein and RB scores compared with baseline at week 4 or at the time of discontinuation were -2.1±1.5 and -2.5±2.0, respectively. Compared with the HA group, changes in fluorescein score were non-inferior and changes in RB score were superior (p=0.019). In addition, diquafosol and HA improved tear film breakup time by 1.046±1.797 and 0.832±1.775 s, respectively (no significant intergroup difference). Adverse event onset rates were 16.3% (40 of 246 subjects) and 10.0% (25 of 251 subjects) in the diquafosol group and HA group, respectively, with borderline significant intergroup differences (p=0.046), while adverse drug reaction incidence rates were 12.2% (30 of 246 subjects) and 6.0% (15 of 251 subjects), respectively (p=0.019). Only mild adverse drug reactions (>2%) in the form of eye discharge, itching or irritation were observed.

CONCLUSIONS

Diquafosol improved fluorescein staining score in a manner similar to HA, and significantly improved RB score compared with HA.

TRIAL REGISTRATION NUMBER

NCT01101984.

Tear cytokine profile as a noninvasive biomarker of inflammation for ocular surface diseases: standard operating procedures

PURPOSE

To provide standard operating procedures (SOPs) for measuring tear inflammatory cytokine concentrations and to validate the resulting profile as a minimally invasive objective metric and biomarker of ocular surface inflammation for use in multicenter clinical trials on dry eye disease (DED).

METHODS

Standard operating procedures were established and then validated with cytokine standards, quality controls, and masked tear samples collected from local and distant clinical sites. The concentrations of the inflammatory cytokines in tears were quantified using a high-sensitivity human cytokine multiplex kit.

RESULTS

A panel of inflammatory cytokines was initially investigated, from which four key inflammatory cytokines (IL-1β, IL-6, INF-γ, and TNF-α) were chosen. Results with cytokine standards statistically satisfied the manufacturer's quality control criteria. Results with pooled tear samples were highly reproducible and reliable with tear volumes ranging from 4 to 10 μL. Incorporation of the SOPs into clinical trials was subsequently validated. Tear samples were collected at a distant clinical site, stored, and shipped to our Biomarker Laboratory, where a masked analysis of the four tear cytokines was successfully performed. Tear samples were also collected from a feasibility study on DED. Inflammatory cytokine concentrations were decreased in tears of subjects who received anti-inflammatory treatment.

CONCLUSIONS

Standard operating procedures for human tear cytokine assessment suitable for multicenter clinical trials were established. Tear cytokine profiling using these SOPs may provide objective metrics useful for diagnosing, classifying, and analyzing treatment efficacy in inflammatory conditions of the ocular surface, which may further elucidate the mechanisms involved in the pathogenesis of ocular surface disease.

[Diagnostics of dry eye]

INTRODUCTION

Dry eye is a multi-factorial disease of tears and ocular surface resulting in symptoms of discomforts, vision disabilities, unstable tear film and possible damage to the ocular surface. The final diagnosis of dry eye results from collecting various data obtained in the course of several diagnostic procedures. DRY EYE - DIAGNOSTIC METHODS: Diagnosis of dry eye involves performing a series of clinical methods and laboratory tests. This paper presents some of the procedures used in the diagnosis of dry eye. Biomicroscopy of the eye with objective tests to check the tear film (Schirmer I, rose bengal, time break up precorneal tear film), verification of corneal sensitivity and impression cytology of the conjunctiva, are the optimum dry eye diagnostic routine procedures.

CONCLUSION

The combination of clinical and histopathological methods of examination of the anterior ocular surface is the basis for a quality and precise diagnosis of dry eye.