Efficacy of Sodium Hyaluronate and Carboxymethylcellulose in Treating Mild to Moderate Dry Eye Disease

Functionally graded hydrogels with opposing biochemical cues for osteochondral tissue engineering

Osteochondral tissue (OC) repair remains a significant challenge in the field of musculoskeletal tissue engineering. OC tissue displays a gradient structure characterized by variations in both cell types and extracellular matrix components, from cartilage to the subchondral bone. These functional gradients observed in the native tissue have been replicated to engineer OC tissuein vitro. While diverse fabrication methods have been employed to create these microenvironments, emulating the natural gradients and effective regeneration of the tissue continues to present a significant challenge. In this study, we present the design and development of CMC-silk interpenetrating (IPN) hydrogel with opposing dual biochemical gradients similar to native tissue with the aim to regenerate the complete OC unit. The gradients of biochemical cues were generated using an in-house-built extrusion system. Firstly, we fabricated a hydrogel that exhibits a smooth transition of sulfated carboxymethyl cellulose (sCMC) and TGF-β1 (SCT gradient hydrogel) from the upper to the lower region of the IPN hydrogel to regenerate the cartilage layer. Secondly, a hydrogel with a hydroxyapatite (HAp) gradient (HAp gradient hydrogel) from the lower to the upper region was fabricated to facilitate the regeneration of the subchondral bone layer. Subsequently, we developed a dual biochemical gradient hydrogel with a smooth transition of sCMC + TGF-β1 and HAp gradients in opposing directions, along with a blend of both biochemical cues in the middle. The results showed that the dual biochemical gradient hydrogels with biochemical cues corresponding to the three zones (i.e. cartilage, interface and bone) of the OC tissue led to differentiation of bone-marrow-derived mesenchymal stem cells to zone-specific lineages, thereby demonstrating their efficacy in directing the fate of progenitor cells. In summary, our study provided a simple and innovative method for incorporating gradients of biochemical cues into hydrogels. The gradients of biochemical cues spatially guided the differentiation of stem cells and facilitated tissue growth, which would eventually lead to the regeneration of the entire OC tissue with a smooth transition from cartilage (soft) to bone (hard) tissues. This promising approach is translatable and has the potential to generate numerous biochemical and biophysical gradients for regeneration of other interface tissues, such as tendon-to-muscle and ligament-to-bone.

Engineering sulfated polysaccharides and silk fibroin based injectable IPN hydrogels with stiffening and growth factor presentation abilities for cartilage tissue engineering

The extracellular matrix (ECM) presents a framework for various biological cues and regulates homeostasis during both developing and mature stages of tissues. During development of cartilage, the ECM plays a critical role in endowing both biophysical and biochemical cues to the progenitor cells. Hence, designing microenvironments that recapitulate these biological cues as provided by the ECM during development may facilitate the engineering of cartilage tissue. In the present study, we fabricated an injectable interpenetrating hydrogel (IPN) system which serves as an artificial ECM and provides chondro-inductive niches for the differentiation of stem cells to chondrocytes. The hydrogel was designed to replicate the gradual stiffening (as a biophysical cue) and the presentation of growth factors (as a biochemical cue) as provided by the natural ECM of the tissue, thus exemplifying a biomimetic approach. This dynamic stiffening was achieved by incorporating silk fibroin, while the growth factor presentation was accomplished using sulfated-carboxymethyl cellulose. Silk fibroin and sulfated-carboxymethyl cellulose (s-CMC) were combined with tyraminated-carboxymethyl cellulose (t-CMC) and crosslinked using HRP/H2O2 to fabricate s-CMC/t-CMC/silk IPN hydrogels. Initially, the fabricated hydrogel imparted a soft microenvironment to promote chondrogenic differentiation, and with time it gradually stiffened to offer mechanical support to the joint. Additionally, the presence of s-CMC conferred the hydrogel with the property of sequestering cationic growth factors such as TGF-β and allowing their prolonged presentation to the cells. More importantly, TGF-β loaded in the developed hydrogel system remained active and induced chondrogenic differentiation of stem cells, resulting in the deposition of cartilage ECM components which was comparable to the hydrogels that were treated with TGF-β provided through media. Overall, the developed hydrogel system acts as a reservoir of the necessary biological cues for cartilage regeneration and simultaneously provides mechanical support for load-bearing tissues such as cartilage.

A comparison between hyaluronic acid and other single ingredient eye drops for dry eye, a review

Dry eye disease (DED) is a highly prevalent and debilitating condition. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan that has a long history as a safe and effective DED treatment. HA is frequently used as a comparator when assessing other topical DED treatments. This study aims to summarise and critically evaluate the literature describing all isolated active ingredients that have been directly compared with HA in the treatment of DED. A literature search was conducted in Embase using Ovid on the 24th of August 2021 and in PubMed including MEDLINE on the 20th of September 2021. Twenty-three studies met the inclusion criteria, 21 of which were randomised controlled trials. Seventeen different ingredients representing six treatment categories were compared with HA treatment. Most measures showed no significant difference between treatments, suggesting either equivalency of treatments or that studies were underpowered. Only two ingredients were represented in more than two studies; carboxymethyl cellulose treatment appears equivalent to HA treatment, while Diquafosol treatment appears superior to HA treatment. Drop-frequency varied from one to eight drops daily. No single study explained the choice of drop frequency. Nine studies used a HA concentration of 0.1% which may be below therapeutic levels. Nine studies reported using preserved formulations, six of them with differences in preservatives between the compared groups. Thirteen studies were financially linked to industry. No major complications were reported. Studies were not designed to find differences in treatment effects for different types or severities of DED. HA is a good comparator treatment when assessing other DED treatments, although consensus after decades of use is still lacking for best choice of concentration, molecular weight and drop tonicity. Well-designed studies are needed to determine an evidence-based standard for HA treatment to be used as comparator.

Artificial Tears: A Systematic Review

Artificial tears are the mainstay of dry eye disease management, but also have a role in corneal abrasion and wound healing, pain and inflammation management, conjunctivitis, keratitis, contact lens rewetting and removal, and foreign body removal. A systematic review of randomized controlled trials (PROSPERO registration CRD42022369619) comparing the efficacy of artificial tears in patients with dry eye to inform prescribing choices using Web of Science, PubMed and Medline databases identified 64 relevant articles. There is good evidence that artificial tears improve symptoms of dry eye disease within a month of regular use, applied about four times a day, but signs generally take several months to improve. Not all patients with dry eye disease benefit from artificial tears, so if there is no benefit over a month, alternative management should be considered. Combination formulations are more effective than single active ingredient artificial tears. Artificial tears containing polyethylene glycol are more effective than those containing carboxymethylcellulose/carmellose sodium and hydroxypropyl methylcellulose. Those classified as having evaporative dry eye disease, benefit from artificial tears with liposomes, especially of higher concentration. The data available is limited by the definition of dry eye disease applied in published studies being variable, as well as the disease severity examined and compliance with artificial tears being rarely quantified.

Sodium hyaluronate 0.30% ocular gel versus sodium hyaluronate 0.18% eye drop in the treatment of moderate to severe dry eye disease

PURPOSE

Compare 0.30% sodium hyaluronate (0.30%HA) ocular gel with 0.18%HA eye drops in terms of improvement of ocular signs and symptoms, in patients with moderate to severe dry eye disease (DED).

METHODS

This was a multicentric, randomized, investigator-masked, non-inferiority, comparative study conducted over 84 days. Three visits were scheduled, testing fluorescein corneal and conjunctival staining (Oxford and Van Bijsterveld scores), tear film break-up time (TBUT), Schirmer test, DED symptoms, 5-Item-Dry-Eye-Questionnaire (5-DEQ), patient and investigator satisfaction and frequency of instillation.

RESULTS

At Day 35 (D35) and Day 84 (D84), both groups (n = 35 each) had a significant improvement in corneal staining (p < 0.001) with no inter-group difference. Van Bijsterveld score improved earlier (D35) for 0.30%HA suggesting a faster effect on conjunctival epithelium healing. There was no difference between the two concentrations in terms of TBUT or Schirmer improvements; however, the Schirmer test increase was only significant for 0.30%HA at D35 (p = 0.040). At D35 and D84, both groups showed similar improvements of DED symptoms and DEQ-5 score. Furthermore, treatment satisfaction was similar for the 2 formulations suggesting that daily use of 0.30%HA do not cause gel-related blurred vision disturbances. Frequency of instillation was similar for both groups.

CONCLUSION

Our study demonstrates the non-inferiority of 0.30%HA gel compared to 0.18%HA solution in patients with moderate to severe DED. Because of its gel formulation and higher HA concentration providing prolonged comfort without causing visual disturbances, 0.30%HA gel might be adapted for bedtime use or during the day in more severe conditions.

Effect of 0.15% sodium hyaluronate on tear film breakup time in healthy anesthetized cats

OBJECTIVES

This study aimed to evaluate the effect of 0.15% sodium hyaluronate (SH) on tear film breakup time (TFBT) in healthy anesthetized cats.

PROCEDURES

Forty cats undergoing elective surgery were enrolled. TFBT was assessed before anesthesia to obtain baseline values. As a preanesthetic medication, cats received midazolam, tramadol, and cetamine combined in the same syringe. For anesthetic induction and maintenance, propofol and isoflurane were used. After a 15 min stabilization period to achieve the surgical anesthetic plane, one eye was treated with one drop of SH, while the other eye received saline and served as a control. TFBT was measured at the end of the general anesthesia (T40) and 35 (T75) and 80 min (T120) after the termination of the anesthesia. TFBT values were compared between the control and SH-treated eyes; both values were also compared with the baseline values (p < .05).

RESULTS

In the control eyes, TFBT significantly decreased from baseline at all time points (p < .001), while in SH-treated eyes, TFBT significantly increased from baseline only at T40 (p < .0001). In SH-treated eyes, TFBT was significantly higher than that in the control eyes at all time points (p < .001).

CONCLUSIONS

In healthy cats, TFBT decreases significantly after 40 min of general anesthesia, and one drop of 0.15% sodium hyaluronate was able to maintain the stability of the tear film for up to 75 min in treated eyes. However, the isolated effect of each drug used in our anesthetic protocol on TFBT should be executed in further studies.

The efficacy of ocular surface assessment approaches in evaluating dry eye treatment with artificial tears

This study evaluates the effectiveness of objective techniques in assessing dry eye disease (DED) treatment compared with the subjective assessment commonly used in clinical practice. Thirty subjects were recruited for two visits separated by 28(± 3) days of treatment with artificial tears. A buttery of common subjective assessment methods were accompanied by a set of objective techniques including measurement of noninvasive tear film break-up time (NIBUT), lipid layer thickness (LLT), and quantitative evaluation of tear film surface quality and dynamics (TFD). Additionally, meibography was performed. Two commercially available videokeratoscopes and a prototype of a lateral shearing interferometer were used for the measurements. Both subjective and objective techniques showed a positive effect of artificial tears in DED treatment. Statistically significant improvements were observed in subjective symptoms (from P < 0.001 for Ocular Surface Disease Index, OSDI to p = 0.019 for tearing), conjunctival redness (P = 0.022), ocular staining (P = 0.012), fluorescein tear film break-up time (P = 0.015), NIBUT (P = 0.037), LLT (P < 0.001), and TFD (P = 0.048). In general, weak or statistically insignificant correlations were observed between subjective and objective assessment methods. The apparent lack of correlation between these methods might indicate the complementary character of objective techniques that likely assess other characteristics of ocular surface health than those assessed subjectively.

Hyaluronic acid in the treatment of dry eye disease

Dry eye disease (DED) is a highly prevalent and debilitating condition affecting several hundred million people worldwide. Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan commonly used in the treatment of DED. This review aims to critically evaluate the literature on the safety and efficacy of artificial tears containing HA used in DED treatment. Literature searches were conducted in PubMed, including MEDLINE, and in Embase via Ovid with the search term: "(hyaluronic acid OR hyaluronan OR hyaluronate) AND (dry eye OR sicca)". A total of 53 clinical trials are included in this review, including eight placebo-controlled trials. Hyaluronic acid concentrations ranged from 0.1% to 0.4%. Studies lasted up to 3 months. A broad spectrum of DED types and severities was represented in the reviewed literature. No major complications or adverse events were reported. Artificial tears containing 0.1% to 0.4% HA were effective at improving both signs and symptoms of DED. Two major gaps in the literature have been identified: 1. no study investigated the ideal drop frequency for HA-containing eyedrops, and 2. insufficient evidence was presented to recommend any specific HA formulation over another. Future investigations assessing the optimal drop frequency for different concentrations and molecular weights of HA, different drop formulations, including tonicity, and accounting for DED severity and aetiology are essential for an evidence-based, individualized approach to DED treatment.

Improving the Mechanical Properties of Damaged Hair Using Low-Molecular Weight Hyaluronate

Chemical treatments of hair such as dyeing, perming and bleaching could cause mechanical damage to the hair, which weakens the hair fibers and makes the hair break more easily. In this work, hyaluronate (HA) with different molecular weight (MW) was investigated for its effects on restoring the mechanical properties of damaged hair. It was found that low-MW HA (average MW~42 k) could significantly improve the mechanical properties, specifically the elastic modulus, of overbleached hair. The fluorescent-labeling experiments verified that the low-MW HA was able to penetrate into the cortex of the hair fiber, while high-MW HA was hindered. Fourier transform infrared spectrometry (FT-IR) results implied the formation of additional intermolecular hydrogen bonds in the HA-treated hair. Thermos gravimetric analysis (TGA) indicated that the HA-treated hair exhibited decreased content of loosely bonded water, and differential scanning calorimetry (DSC) characterizations suggested stronger water bonding inside the HA-treated hair, which could alleviate the weakening effect of loosely bonded water on the hydrogen bond networks within keratin. Therefore, the improved elastic modulus and mechanical strength of the HA-treated hair could be attributed to the enhanced formation of hydrogen bond networks within keratin. This study illustrates the capability of low-MW HA in hair damage repair, implying an enormous potential for other moisturizers to be used in hair care products.

A randomized multicenter evaluation of the efficacy of 0.15% hyaluronic acid versus 0.05% cyclosporine A in dry eye syndrome

Hyaluronic acid (HA) and cyclosporine A (CsA) eyedrops are commonly prescribed in dry eye syndrome (DES). The effectiveness of each preparation in DES is well-known, yet the superiority of one over another has been studied little. We assessed the efficacy and tolerability of 0.15% HA compared to combinations of 0.05% CsA plus 0.5% carboxymethylcellulose (CMC), and 0.15% HA plus 0.05% CsA in patients with moderate to severe DES. Total 438 patients with moderate to severe DES were recruited and randomized for one of the three treatments for 12 weeks. Effectiveness was assessed at baseline, 4- and 12-weeks. The primary endpoint was change in corneal staining score. The secondary endpoints were tear break-up time (TBUT), strip meniscometry (SM) score, ocular surface disease index (OSDI) score, and tolerability questionnaire. The change in corneal staining score for 0.15% HA from the baseline was non-inferior to that of 0.05% CsA. Corneal staining score, TBUT, SM score, and OSDI score improved in all groups without statistically significant intergroup differences. Better tolerability and lower prevalence of adverse drug reactions were seen in 0.15% HA. Our findings suggest that 0.15% HA may be equivalently effective and safer than 0.05% CsA in treating moderate to severe DES.

Supportive treatment to chemotherapy with MMC, in patients with ocular surface squamous neoplasia or conjunctival melanocytic tumor

PURPOSE

Since there is a lack of clear information regarding the benefit to combine supportive therapies (such as artificial tears) to mitomycin C (MMC) in the treatment of ocular surface neoplasia, the primary purpose of the study was to evaluate hyaluronic acid eye drops and hyaluronic acid-conjugated lactobionic acid (LACTOyal FREE) eye drops as supportive therapy.

METHODS

Retrospective evaluation of patients with ocular surface squamous neoplasia or conjunctival melanocytic tumor treated with MMC, who had used also artificial tears as supportive treatment. A 6-month follow-up with evaluation of subjective and objective tests for ocular surface integrity was conducted.

RESULTS

A total of 35 patients were analyzed, most of them with squamous disease (71.4%). The break-up time (BUT), Ocular Surface Disease Index (OSDI) and Schirmer test values showed a significant difference at any time point with overall population. No statistical difference was found among subgroups (Lactoyal vs No Lactoyal).

CONCLUSION

The use of an ancillary therapy based on hyaluronic acid allows to improve both subjective and objective ocular parameters, reducing MMC induced adverse effects. Meantime, hyaluronic acid-conjugated lactobionic acid eye drops highlighted the same advantages with a more positive trend in OSDI results.

An investigation into the effects of ocular nebulization combined with meibomian gland massage on ocular surface status and corneal higher-order aberrations for the treatment of meibomian gland dysfunction

PURPOSE

To evaluate ocular surface status and corneal higher-order aberrations after a new ocular nebulization therapy combined with meibomian gland massage for the treatment of meibomian gland dysfunction (MGD).

PATIENTS AND METHODS

This prospective randomized study involved 38 patients diagnosed with MGD. Subjects were classified into two groups: the nebulization and meibomian gland massage group (or NB group, 14 patients, 28 eyes) and the eye drop group (or ED group, 24 patients, 48 eyes). Azithromycin solution and esculin and digitalis glycoside eye drops were tested in the therapy. Best-corrected visual acuity (BCVA) testing; noncontact tonometry; fundoscopy; the Ocular Surface Disease Index (OSDI) questionnaire; tear film assessment encompassing tear meniscus height (TMH) and non-invasive keratograph breakup time (NIKBUT); corneal fluorescein staining; the Schirmer I test (SIT); and anterior, posterior and total corneal aberrations were evaluated at 1 and 3 months after treatment.

RESULTS

At 3 months, the NB group showed significantly better improvement than the ED group in terms of TMH (0.23 ± 0.04 versus 0.19 ± 0.05, p = 0.002) and first breakup time (f-BUT; 7.42 ± 2.49 versus 5.53 ± 2.12, p = 0.001). The average breakup time (Av-BUT) of the NB group was significantly longer than that of the ED group at 1 month (9.52 ± 2.70 versus 8.02 ± 2.33, p = 0.013) and 3 months (5.53 ± 2.12 versus 8.35 ± 2.38, p = 0.018). Both groups achieved improvement in corneal fluorescein staining (CFS) and SIT results at 1 and 3 months (p < 0.05). At the 3-month follow-up, anterior corneal trefoil aberrations decreased significantly in the NB group (p = 0.008), and improvements in anterior corneal coma aberrations and posterior corneal higher-order aberrations (HOAs) were observed in the ED group (p < 0.05) over the 4 mm pupil zone. Over a 6 mm zone at 3 months, anterior, posterior and total trefoil aberrations as well as total HOAs were significantly decreased in the NB group (p < 0.05), while posterior HOAs and trefoil aberrations were found to be decreased in the ED group (p < 0.05). For individual Zernike terms, anterior and total corneal Z(3, -3) showed decreases over the 4 and 6 mm zones, while no improvement was detected in the NB group at 3 months.

CONCLUSION

In terms of comfort and visual quality, nebulization therapy combined with meibomian gland massage to deliver azithromycin solution and esculin and digitalis glycoside eye drops appears to be more effective in treating clinical symptoms and signs of MGD than simply applying esculin and digitalis glycoside eye drops.

A randomized multicenter clinical evaluation of sequential application of 0.3% and 0.15% hyaluronic acid for treatment of dry eye

PURPOSE

We report the clinical efficacy of sequential applications of 0.3% and 0.15% unpreserved hyaluronic acid (HA) for the treatment of dry eye disease (DED).

STUDY DESIGN

Randomized clinical trial.

METHODS

Patients over 19 years of age with DED level 2 or higher, corneal fluorescein staining (CFS) score > 1, and tear break-up time (TBUT) < 10 s were included. Seventy-six patients were randomly assigned to the 0.15% HA group, 0.3% HA group, or combination group. Each group applied two drops of 0.15% or 0.3% HA, or a single drop of both 0.3% and 0.15% HA. Patients were evaluated using the ocular surface disease index (OSDI), CFS and conjunctival fluorescein stain score, TBUT, and blurring/discomfort after application at baseline, 4 weeks, and 8 weeks.

RESULTS

The combination group had the greatest improvement in CFS score from baseline to 8 weeks, compared with the 0.15% and 0.3% HA group (p < 0.001). The combined CFS-OSDI responder rates of the combination group (CFS score = 0 and OSDI ≥ 50% improvement at 8 weeks) were significantly higher than those of the 0.15% and 0.3% groups (p = 0.037). At 4 and 8 weeks, blurring after application in both the 0.3% and combination groups was significantly higher than in the 0.15% group, despite no difference between the 0.3% and combination groups. There were no differences in CFS and conjunctival staining score, TBUT, or OSDI within the three groups at baseline, 4 weeks, and 8 weeks.

CONCLUSIONS

Sequential application of 0.3% and 0.15% HA improved symptoms/signs in moderate to severe DED patients.

Efficacy of hyaluronic acid 0.3%, cyanocobalamin, electrolytes, and P-Plus in menopause patients with moderate dry eye disease

Purpose

To study the treatment efficacy of hyaluronic acid 0.3%, cyanocobalamin (vitamin B12), electrolytes, and P-Plus in menopausal patients with moderate dry eye disease.

Methods

Thirty female patients of mean age 53.06 ± 5.20 years (45–65) were enrolled in this prospective longitudinal study. Meibomian gland loss assessment was determined using a scale with four levels. The Ocular Surface Disease Index (OSDI) questionnaire, phenol red thread (PRT) test, and tear film break-up time (TFBUT) were also completed by the patients. Tear eye drops were formulated with 0.3 g of sodium hyaluronate, P-Plus ™, vitamin B12, sodium chloride, potassium chloride, calcium chloride, magnesium chloride, and SCO® (stabilized complex oxychloride). After 30 days, the patients were re-evaluated.

Results

The mean meibomian gland loss percentage was 37.97 ± 19.02 % (7.20 to 88.30%). Before treatment, the OSDI was 22.53 ± 14.03 score points (6.25 to 77.08). Posterior OSDI decreased to 16.26 ± 13.69 score points (0.00 to 70.83) (W = 58.00, P < 0.01). Before treatment, PRT was 10.31 ± 4.48 mm (4.00 to 21.00). Posterior PRT increased to 15.41 ± 6.27 mm (4.00 to 21.00) (W = 1520.50, P < 0.01). Before treatment, TFBUT was 6.23 ± 1.75 s (3.00 to 9.00). The posterior TFBUT increased to 8.10 ± 2.06 s (4.00 to 14.00) (W= 1382.50, P < 0.01).

Conclusion

The hyaluronic acid 0.3% and vitamin B12 eye drops effectively decreased dry eye symptoms in menopausal women and improved tear stability and volume.

Therapie des Trockenen Auges

Die Therapie des Trockenen Auges stellt eine schwierige Aufgabe für den behandelnden Augenarzt dar. Fortschritte in unserem Verständnis der Risikofaktoren, der Ätiologie und Pathophysiologie des Trockenen Auges haben zu einer Weiterentwicklung der Behandlungsstrategien geführt. Vor Beginn der Therapie ist die korrekte Zuordnung in eine wässrig-muzinöse Tränenfilmdysfunktion (Mindersekretion), in eine lipidbedingte Tränenfilmdysfunktion (hyperevaporative Form durch eine abnormen Meibom-Drüsen-Physiologie) oder in eine variable Kombination wichtig. Unter Berücksichtigung aktueller Empfehlungen der DOG, des BVA und des TFOS DEWS II Unterausschusses wurde ein Behandlungsalgorithmus abgeleitet, der ein schrittweises Vorgehen je nach Schweregrad der Erkrankung darstellt.

Comparison of efficacy of trehalose-based eye drops versus topical 0.1% Hyaluronic Acid for management of clinically significant dry eye using non-invasive investigational modalities

PURPOSE

To compare the efficacy of trehalose-HA eye drops versus 0.1% hyaluronic acid for the treatment of dry eye.

METHODS

This prospective, comparative, contralateral eye study included sixty eligible patients (mean age 44.13 ± 14.53 years). Patients having a SPEED questionnaire score of 16 or above, objective scatter index (OSI) > 1 and non-invasive tear break up time (NIBUT) of 10 s or less were included in the study. Eyes were randomized to receive 0.1% hyaluronic acid (HA) in one eye and trehalose-HA eye drops in the contralateral eye. At baseline, 1- and 3-month follow-ups, OSI, NIBUT, MG loss, tear meniscus height (TMH) and tear film osmolarity (TFO) were evaluated using non-invasive modalities RESULTS: There was a statistically significant improvement in NIBUT, TMH, OSI, SPEED questionnaire score in the trehalose-HA compared to the 0.1% HA group at both 1- and 3-month visits (p < 0.05). In both the study groups, compared to the baseline, the mean values of TFO, MG loss, OSI and SPEED questionnaire score significantly reduced at 3 months (p < 0.05). The mean values of NIBUT and tear meniscus height on the other hand showed a significant increase compared to the baseline values (p < 0.05). Both drugs were well tolerated by the study participants without any significant ocular side effects.

CONCLUSION

Trehalose-HA was found to be more effective than 0.1% HA eye drops in the management of symptomatic dry eye, as shown by significant reduction in NIBUT, TMH and OSI, when evaluated using non-invasive modalities of dry eye evaluation.

Carboxymethyl Cellulose versus Hydroxypropyl Methylcellulose Tear Substitutes for Dry Eye Due to Computer Vision Syndrome: Comparison of Efficacy and Safety

Background:

Prolonged use of visual display terminal images on electronic devices such as computers frequently leads to symptoms of dry eye. Tear substitutes form the mainstay of treatment for mild-to-moderate dry eye.

Aim:

The study aimed to evaluate the efficacy and safety of carboxymethyl cellulose (CMC) versus hydroxypropyl methylcellulose (HPMC) tear substitutes for dry eye due to computer vision syndrome (CVS).

Materials and Methods:

This was a prospective, randomized, comparative, and open-labeled study. The efficacy of CMC 0.5% and HPMC 0.3% tear substitutes was compared in 180 participants (90 in each group) with dry eye. Change in Ocular Surface Disease Index (OSDI) score, Schirmer I test score, and tear film break up time (TF-BUT) were used as efficacy parameters. Safety was monitored on all visits.

Results:

The baseline OSDI score? 23.48 and 23.32 in Group A and B, respectively, decreased with treatment in both groups on all follow-up visits as compared to the baseline (day 90: 13.9 ± 3 vs. 14.81 ± 3.17, P: 0.01). The scores of Schirmer I test increased in both groups, with a greater improvement in Group A (at day 90: 22.75 ± 3.04 mm vs. 21.78 ± 3.36 mm, P: 0.04). The values of TF-BUT improved in both groups, the difference being statistically insignificant. An initial stinging was reported by one participant, each in both groups.

Conclusion:

CMC and HPMC tear substitutes were equally efficacious and safe in reducing symptoms of dry eye due to CVS.

A Meta-Analysis of the Efficacy of Hyaluronic Acid Eye Drops for the Treatment of Dry Eye Syndrome

Hyaluronic acid (HA) is commonly used for treating dry eye syndrome (DES). This meta-analysis was performed to compare the efficacies of HA- and non-HA-based eye drops, including saline and conventional artificial tears (ATs), for the treatment of dry eye disease. Eight databases (PubMed, EMBASE, Cochrane Central Register of Controlled Trials, DBpia, KoreaMed, KMBASE, RISS, KISS) were searched for studies comparing the efficacies of HA- and non-HA-based ATs in patients with DES published up to September 2020. Two independent reviewers assessed the quality and extracted the relevant data. The mean differences of Schirmer's (SH) test scores, tear breakup times (TBUT), corneal fluorescein staining scores (Oxford scale, 0-4), and ocular surface disease indexes were calculated. The standard mean difference and 95% confidence interval were calculated using a random effect model. Nineteen studies, including 2078 cases, were included. HA eye drops significantly improved tear production compared with non-HA-based eye drops (standard mean difference (SMD) 0.18; 95% confidence interval (CI) 0.03, 0.33). In a subgroup analysis, the SH test scores and TBUT values after using HA significantly increased compared to those measured after using saline (SMD 0.27; 95% CI 0.05, 0.49 and SMD 0.28; 95% CI 0.03, 0.52, respectively). Based on these results, HA eye drops may be superior to non-HA eye drops including normal saline and ATs. Further research is needed to assess the efficacies stratified by age, treatment duration, the severity of dry eye, and optimal dosages.

The short term effect of trehalose and different doses of sodium hyaluronate on anterior corneal aberrations in dry eye patients

AIM

To evaluate the short-term effect of 0.15% sodium hyaluronate (SH), 0.20% SH, and Trehalose + 0.15% SH on anterior corneal aberrations in dry eye patients.

METHODS

76 eyes of 76 dry eye patients were divided into three groups. Non-preserved 1.5 mg/mL SH was administered in group 1, non-preserved 2.0 mg/mL SH was administered in group 2, and non-preserved trehalose 30 mg/mL and 1.5 mg/mL SH was administered in group 3. Aberrometry measurements were performed before and 10 min after application of the artificial tear drop. Using the Pentacam Scheimpflug imaging system, total root mean square (RMS), lower-order aberration (LOA), higher-order aberrations (HOAs), spherical aberration (SA), trefoil, and coma aberrations were investigated.

RESULTS

In each group; the RMS of total, LOA, HOAs, and spherical aberration were significantly decreased after the artificial drop instillation, compared with those of them at baseline; and in groups 1 and 2, vertical trefoil term was also significantly increased, compared with those of them at baseline. According to intergroup analyzes, there was no significant outcome.

CONCLUSIONS

It was observed that three artificial tears reduced the anterior corneal aberrations, in a 10-min period. The short-term effect of three artificial tears on the anterior corneal aberration was similar.

Safety and Efficacy of a Preservative-Free Artificial Tear Containing Carboxymethylcellulose and Hyaluronic Acid for Dry Eye Disease: A Randomized, Controlled, Multicenter 3-Month Study

Purpose

To compare the efficacy and safety of an artificial tear combining the polymers carboxymethylcellulose (CMC) and hyaluronic acid (HA), to a formulation of CMC alone in subjects with dry eye.

Methods

A preservative-free artificial tear (CMC-HA) was compared with an existing artificial tear (CMC). Subjects with mild-to-severe signs and symptoms of dry eye were enrolled in this double-masked, randomized, multicenter trial, and dosed at least twice daily for 90 days, with follow-up visits at Days 7, 30, 60, and 90. Ocular Surface Disease Index (OSDI) was the primary outcome measure. Secondary outcome measures were tear break-up time (TBUT), ocular surface staining, Schirmer test with anesthesia, and visual analog scale (VAS) scores of dry eye symptom severity and formulation acceptability. Safety measures included adverse events, biomicroscopy, and visual acuity.

Results

A total of 460 subjects were enrolled across 45 sites (38 in Europe; 7 in Australia), of whom 454 were randomized to receive treatment. The per-protocol (PP) population consisted of 394 subjects, 364 (92.4%) of whom completed the study. In the PP population, the mean ± SD change from baseline in OSDI score at the primary timepoint, Day 90, was −16.9±17.5 for CMC-HA and −16.0±16.1 for CMC. CMC-HA was non-inferior to CMC based upon a confidence interval method. Both treatments significantly improved (P<0.001) OSDI, symptom VAS scores, TBUT, and ocular surface staining from baseline at all follow-up visits, with minimal differences between groups. Greater reduction of overall ocular pain/discomfort was reported in subjects using CMC-HA versus CMC (P=0.048). Approximately 10% of subjects in each group reported treatment-related adverse events of generally mild to moderate severity.

Conclusion

The new CMC-HA formulation was effective and well tolerated, and demonstrates a greater potential for symptom relief compared with CMC. These data support implementation of this formula for the management of dry eye patients.

In Vitro and Ex Vivo Evaluation of Nepafenac-Based Cyclodextrin Microparticles for Treatment of Eye Inflammation

The aim of this study was to design and evaluate novel cyclodextrin (CD)-based aggregate formulations to efficiently deliver nepafenac topically to the eye structure, to treat inflammation and increase nepafenac levels in the posterior segment, thus attenuating the response of inflammatory mediators. The physicochemical properties of nine aggregate formulations containing nepafenac/γ-CD/hydroxypropyl-β (HPβ)-CD complexes as well as their rheological properties, mucoadhesion, ocular irritancy, corneal and scleral permeability, and anti-inflammatory activity were investigated in detail. The results were compared with a commercially available nepafenac suspension, Nevanac^® 3 mg/mL. All formulations showed microparticles, neutral pH, and negative zeta potential (–6 to –27 mV). They were non-irritating and nontoxic and showed high permeation through bovine sclera. Formulations containing carboxymethyl cellulose (CMC) showed greater anti-inflammatory activity, even higher than the commercial formulation, Nevanac^® 0.3%. The optimized formulations represent an opportunity for topical instillation of drugs to the posterior segment of the eye.

Improvement of ferning patterns of lubricant eye drops mixed with various electrolytes and carboxymethylcellulose

PURPOSE

To investigate the effect of the addition of electrolytes, basic tear solution (BTS), and sodium carboxymethylcellulose (SCMS) on the tear ferning (TF) patterns of Blink Contact Soothing Eye Drops^® and Refresh Plus Tears^®.

METHOD

Samples of Blink Contact Soothing Eye Drops^® and Refresh Plus Tears^® (10 μL) were mixed with different volumes (3-30 μL) of several electrolytes, namely sodium chloride, potassium chloride, calcium chloride, magnesium chloride hexahydrate, sodium hydrogen carbonate, and sodium dihydrogen phosphate, BTS, and SCMS. Samples (1 μL) of the mixtures were dried on a glass slide at room temperature and the TF patterns were inspected using a light microscope, graded using the Masmali five-point grading scale and compared to the corresponding TF grades of the artificial tears.

RESULTS

The TF grades of Blink Contact Soothing Eye Drops^® and Refresh Plus Tears^® improved from 1.2 and 1.5, respectively to 0.2 when calcium chloride was used as the electrolyte. Improvements in TF grades were also observed when other electrolytes (e.g., sodium dihydrogen phosphate), BTS, and SCMS were used.

CONCLUSION

The tear ferning test can be used to evaluate the effect of the addition of electrolytes to an artificial tear in-vitro. The TF patterns of artificial tear solutions such as Blink Contact Soothing Eye Drops^® and Refresh Plus Tears^® can be improved with the addition of various concentrations of electrolytes, BTS, and SCMS, however further research is still needed to understand the clinical relevance of TF patterns with respect to the management of dry eye symptoms and their potential role in the development of new artificial tears.

Management of congenital ichthyoses: European guidelines of care, part two

These guidelines for the management of congenital ichthyoses have been developed by a multidisciplinary group of European experts following a systematic review of the current literature, an expert conference held in Toulouse in 2016, and a consensus on the discussions. These guidelines summarize evidence and expert-based recommendations and intend to help clinicians with the management of these rare and often complex diseases. These guidelines comprise two sections. This is part two, covering the management of complications and the particularities of some forms of congenital ichthyosis.

Effect of 0.15% sodium hialuronate and 0.5% carboxymethylcellulose on tear film breakup time in healthy dogs and in dogs with keratoconjunctivitis sicca

ABSTRACT This study aimed to evaluate the effect of the 0.15% sodium hyaluronate (SH) and of 0.5% carboxymethylcellulose (CMC) on tear film breakup time (TFBUT) in 10 healthy dogs and in 32 eyes of dogs with keratoconjunctivis sicca (KCS). In addition, the goblet cell density (GCD) of this population was quantified. TFBUT was assessed at baseline and at different time points following the instillation of SH and CMC. KCS was graded as mild, moderate, and severe. GCD were quantified from conjunctival biopsies. The number of GCD differed significantly between patients with mild and moderate KCS (P<0.01). TFBUT of healthy dogs increased only for 1 minute after treatment with SH (P<0.01). Regarding baseline and treatments, SH significantly increased TFBUT for up to 30 minutes on the ocular surface, in comparison to CMC, in all categories of KCS (P<0.01). TFBUT and GCD correlated positively when the healthy and diseased eyes were grouped (r=0.41, P=0.006). It can be concluded that in dogs with KCS, SH lasts longer periods on the ocular surface than CMC, but such agents does not increase TFBUT in healthy dogs. Additionally, tear film stability tends to reduce in a linear fashion from the mild to severe form of KCS.

Effects of Lipid- Versus Sodium Hyaluronate-Containing Eye Drops on Optical Quality and Ocular Surface Parameters as a Function of the Meibomian Gland Dropout Rate

PURPOSE

To evaluate the effect of lipid- versus sodium hyaluronate-based eye drops on optical quality and ocular surface parameters.

METHODS

Sixty eyes of 30 patients with mild-to-moderate dry eye disease were included in a prospective randomized study. Each patient received either lipid- or sodium hyaluronate-based eye drops. Ocular symptom scores, breakup time, Schirmer test, fluorescein staining, noncontact meibography, and aberrometry were evaluated before and after 3 months of therapy.

RESULTS

At the 3-month visit, a statistically significant improvement (P ≤ 0.05) was noted in both groups on the Schirmer test, breakup time, ocular surface staining, and symptom score. In the lipid group, patients with progressive meibomian gland (MG) loss (>50%) showed a significantly greater increase in their corneal higher-order (HO) Strehl ratio (0.25 ± 0.26 vs. -0.01 ± 0.25, P = 0.02) and modulation transfer function (MTF) (0.12 ± 0.17 vs. -0.02 ± 0.06, P = 0.03) than patients with less advanced MG disease. In the lipid group, a significant positive correlation was noted between the MG dropout rate and improvement in Schirmer values [Spearman correlation coefficient (CC): 0.79], corneal HO Strehl (CC: 0.75), and HO modulation transfer function (CC: 0.6), but a significant negative correlation was noted between the MG dropout rate and the HO root mean square (CC: -0.73).

CONCLUSIONS

Lipid-containing artificial tears seem to be superior to sodium hyaluronate-containing drops in terms of improving HO aberrations and optical quality in patients with significant MG dysfunction.

Comparative study of 0.1% hyaluronic acid versus 0.5% carboxymethylcellulose in patients with dry eye associated with moderate keratitis or keratoconjunctivitis

Background

Eye drops containing 0.1% hyaluronic acid (HA) and 0.5% carboxymethylcellulose (CMC) applied one drop three times a day per affected eye were compared in patients with moderate keratitis or keratoconjunctivitis related to dry eye disease (DED).

Patients and methods

This was a prospective, randomized, multicenter, Phase IIIB noninferiority study, with a single-masked phase in parallel mode with two groups over 84 days. The primary efficacy outcome was change in ocular surface (OS) staining between day 0 (D0) and day 35 (D35). The conjunctiva and cornea were stained with lissamine green and fluorescein. Secondary efficacy measures at day 84 (D84) were OS-staining score (SS), ocular comfort index, tear-film breakup time and how patients and investigators rated treatment efficacy and safety.

Results

At D35, 0.1% HA achieved a 46.6% reduction in OS-SS (−2.03±1.35 points, n=39 patients) and 0.5% CMC treatment, followed by a 34.9% reduction (−1.61±1.69 points, n=38 patients) compared to D0. At D84, the SS difference to D0 improved by −2.58±1.45 points (−59.2%) for 0.1% HA and −2.59±2.27 points (−54.4%) for 0.5% CMC. Ocular comfort-index scores improved, with significantly lower (better) values for stinging and itching on D84 for 0.1% HA. Patients assessed treatment with 0.1% HA as significantly better than 0.5% CMC (Likert scale, 4.82 vs 3.97; P=0.018). Four adverse events (AEs) occurred in four of 41 patients (9.8%) treated with 0.1% HA, and three AEs in two of 39 patients (5.1%) treated with 0.5% CMC. No serious AEs were noted.

Conclusion

DED signs and symptoms of DED significantly improved with both eye drops. OS staining improved >54% at D84. Treatment was well tolerated, with only minor AEs <10%. 0.1% HA and 0.5% CMC were equally safe and effective. Significant and nonsignificant results were constantly in favor of 0.1% HA.

[Novel current and future therapy options for treatment of dry eye disease]

Dry eye disease was redefined by the dry eye workshop (DEWS II) in May 2017. According to the new definition "dry eye is a multifactorial disease of the ocular surface characterized by a loss of homeostasis of the tear film and accompanied by ocular symptoms". The current definition encompasses etiological factors, such as instability and hyperosmolarity of the tear film, ocular surface inflammation and damage as well as a new aspect compared to the former definition, neurosensory abnormalities. Recent and future therapeutic options for dry eye focus on treatment of the aforementioned pathogenetic events. New tear substitutes, medications and devices to stimulate tear production, innovative anti-inflammatory treatment, medications to influence corneal innervation and new methods for treatment of Meibomian gland dysfunction are already available or will be available in the near future.

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.

Investigating the potential benefits of a new artificial tear formulation combining two polymers

PURPOSE

Artificial tear formulations typically contain a water-soluble polymer to enhance residence time, moisture retention, and binding to the mucin coat of the ocular surface, which facilitate corneal healing. This study investigated the potential advantages of combining carboxymethylcellulose (CMC) and hyaluronic acid (HA) polymers in a single formulation.

MATERIALS AND METHODS

Individual CMC and HA solutions were prepared and tested for bulk viscosity in comparison to a solution that combined CMC and HA. Rheometry determined the differences between solutions at increasing shear rates, simulating eye movement and blinking.

RESULTS

The bulk viscosity of the individual 0.5% CMC and 0.1% HA solutions was 2.5 and 5.7 cP, respectively. The viscosity of the combined solution (13.1 cP) was 60% higher than predicted by additive effects. Rheometry revealed shear rates between 10/second (open eye) and 10,000/second (blinking eye). At these rates, viscosity ranged from 2.7 to 3.5 cP for 0.5% CMC, 2.8 to 6.8 cP for 0.1% HA, and 5.2 to 15.3 cP for the 0.5% CMC-0.1% HA combination. Low-shear viscosity of the CMC-HA combination increased 48% over the sum of the individual solutions, but high-shear viscosity remained virtually unchanged. Data from CMC and HA solutions at higher concentrations were consistent with these results.

CONCLUSION

Combining CMC and HA polymers produced a synergistic increase in low-shear viscosity (which cannot be fully explained by simple molecular entanglement), while the high-shear viscoelasticity of the combined solution remained unaffected. These data suggest that CMC-HA combinations have properties that may be used to formulate artificial tears that optimize ocular retention (through higher low-shear viscosity), while minimizing blur and stickiness during blinking (through lower high-shear viscosity).

Potential Applications of Nanocellulose-Containing Materials in the Biomedical Field

Because of its high biocompatibility, bio-degradability, low-cost and easy availability, cellulose finds application in disparate areas of research. Here we focus our attention on the most recent and attractive potential applications of cellulose in the biomedical field. We first describe the chemical/structural composition of cellulose fibers, the cellulose sources/features and cellulose chemical modifications employed to improve its properties. We then move to the description of cellulose potential applications in biomedicine. In this field, cellulose is most considered in recent research in the form of nano-sized particle, i.e., nanofiber cellulose (NFC) or cellulose nanocrystal (CNC). NFC is obtained from cellulose via chemical and mechanical methods. CNC can be obtained from macroscopic or microscopic forms of cellulose following strong acid hydrolysis. NFC and CNC are used for several reasons including the mechanical properties, the extended surface area and the low toxicity. Here we present some potential applications of nano-sized cellulose in the fields of wound healing, bone-cartilage regeneration, dental application and different human diseases including cancer. To witness the close proximity of nano-sized cellulose to the practical biomedical use, examples of recent clinical trials are also reported. Altogether, the described examples strongly support the enormous application potential of nano-sized cellulose in the biomedical field.

Sodium Hyaluronate in the Treatment of Dry Eye Syndrome: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis compares sodium hyaluronate (HY) with non-HY based artificial tears in the treatment of dry eye syndrome. A literature search for clinical trials comparing HY against non-HY preparations was conducted across PubMed, Cochrane Central Register of Controlled Trials and Scopus databases from inception up to May 2016. Majority of the 18 studies selected for review showed superiority of HY in improving ocular staining and symptoms. Randomized controlled trials (RCTs) examining Schirmer's I (SH) and tear breakup time (TBUT) underwent further meta-analyses with calculation of pooled standardized mean differences (SMDs) with 95% confidence intervals (CIs). 7 RCTs including 383 eyes randomized to HY and 596 eyes to non-HY preparations underwent meta-analysis for SH. 9 RCTs including 458 eyes randomized to HY and 651 eyes to non-HY preparations underwent meta-analysis for TBUT. By fixed-effects modelling, HY demonstrated greater improvement of SH compared to non-HY preparations (SMD, 0.238; 95% CI, 0.107 to 0.369; p < 0.001). By random-effects modelling, HY demonstrated less improvement of TBUT (SMD, -0.566; 95% CI, -1.099 to -0.0336; p = 0.037). In summary, neither preparation was shown to be consistently superior across all outcome measures. The difference in effect between preparations on SH and TBUT was not clinically significant.

Can the optimum artificial tear treatment for dry eye disease be predicted from presenting signs and symptoms?

PURPOSE

To assess dry eye treatment with four preservative-free dry eye artificial tear treatments to facilitate evidence-based prescribing.

METHODS

A randomised, single masked crossover trial of Clinitas Soothe, Hyabak, Tears Again and TheraTears artificial tears was conducted on 50 symptomatic dry eye patients, aged 60.8±14.2years. At baseline and after trialling each treatment for 4 weeks, signs and symptoms were assessed using the Ocular Surface Disease Index (OSDI), non-invasive tear break-up time, fluorescein tear break-up time, tear meniscus height (TMH), Phenol Red test, lid-parallel conjunctival folds (LIPCOF), ocular surface staining, and lipid layer grading and osmolarity (baseline visit only).

RESULTS

OSDI (p=0.002), LIPCOF (p=0.014) and conjunctival staining (p<0.001) significantly improved from baseline, however, the impact of each dry eye treatment on ocular symptoms and signs was similar. Clinitas Soothe and Hyabak were preferred by 34%/30% of participants, but only subjective comparison with the other drops influenced this choice. TheraTears was preferred (by 24%) by those with a lower baseline tear volume (p=0.01) and Tears Again (by 12%) by those with a thinner baseline lipid layer (p=0.04). The treatment that afforded the greatest improvement in clinical signs did not consistently match each individual's preferred treatment.

CONCLUSIONS

If prescribed to a general dry eye population, the artificial tears performed similarly, improving symptoms and conjunctival signs. However, osmolarity balanced artificial tears were the preferred treatment in individuals with low baseline tear volume and lipisomal spray for individuals with a baseline lipid layer deficiency.

Dry Eye Treatment Based on Contact Lens Drug Delivery: A Review

Dry eye disease affects a substantial segment of the word population with increasing frequency. It is a multifactorial disease of the ocular surface and tear film, which causes ocular discomfort, visual disturbances, and tear instability with potential damage to the cornea and conjunctiva. Because of its multifactorial etiology, the use of different pharmacological treatment for dry eye treatment has been proposed, which include anti-inflammatory molecules, lubricants or comfort agents, and secretagogues. However, in some cases these pharmacological approaches only relieve symptoms temporarily, and consequently, eye care professionals continue to have difficulties managing dry eye. To improve pharmacological therapy that allows a more efficient and long-term action, effective ocular drug delivery of the currently available drugs for dry eye treatment is required. Contact lenses are emerging as alternative ophthalmic drugs delivery systems that provide an increased residence time of the drug at the eye, thus leading to enhanced bioavailability and more convenient and efficacious therapy. In this article, we reviewed the different techniques used to prepare contact lens-based drug delivery systems and focused on articles that describe the delivery of compounds for dry eye treatment through contact lenses.

Osmoprotectants, carboxymethylcellulose and hyaluronic acid multi-ingredient eye drop: a randomised controlled trial in moderate to severe dry eye

Purpose

To assess the safety and efficacy of an eye drop combining osmoprotectants, carboxymethylcellulose and hyaluronic acid (O/CMC/HA) in reducing symptomatic, moderate to severe dry eye, compared with HA.

Methods

In this investigator-masked, randomised study, patients instilled 1–2 drops/eye of O/CMC/HA or HA (2–6 times/day) for 3 months. Primary endpoint: mean change in Global Ocular Staining Score (GOSS) from baseline at day 35. Noninferiority of O/CMC/HA was tested in the per-protocol population; if achieved, superiority was tested in the intent-to-treat population. Secondary efficacy endpoints: mean change from baseline in GOSS, Ocular Surface Disease Index (OSDI), Schirmer score, tear break-up time (TBUT), corneal/conjunctival staining, conjunctival hyperaemia, symptoms, and patient/investigator assessments.

Results

Baseline characteristics were comparable between groups (n=40 each). O/CMC/HA was noninferior (and not superior) to HA based on similar GOSS reductions from baseline at day 35 and month 3 in both groups (P=0.778, day 35, per-protocol population). Overall, O/CMC/HA and HA provided similar reductions in OSDI, Schirmer score, TBUT, corneal staining and hyperaemia from baseline at 35 days (P≥0.155). More patients reported less severe stinging/burning, sandiness/grittiness, and painful/sore eyes at month 3 with O/CMC/HA (P≤0.039), and more rated the dropper bottle easy to use (87.5%), compared with HA (46.2% P=0.002). Other patient and investigator assessments were similar between groups. O/CMC/HA and HA were well tolerated.

Conclusions

O/CMC/HA is noninferior to HA in improving objective signs of dry eye, with potential advantages for subjective symptoms and patient acceptance.

Efficacy and Safety of 0.2% Hyaluronic Acid in the Management of Dry Eye Disease

OBJECTIVES

To evaluate the safety and efficacy of a new artificial tear containing 0.2% hyaluronic acid, as compared with 0.9% saline solution, in mild dry eye patients after 1-month use in a crossover study design with washout periods.

METHODS

Overall, 16 mild dry eye patients were included. After a week of washout, every patient used the experimental product (Visaid 0.2%) and the control product (0.9% saline solution), each for a month (3-8 drops daily). Both products were preservative free. The percentage change for the following variables were calculated and analyzed: Ocular Surface Disease Index (OSDI) questionnaire, visual acuity, intraocular pressure, ophthalmoscopy evaluation, biomicroscopy findings, fluorescein corneal staining and lissamine green conjunctival staining, tear breakup time, contrast sensitivity, Schirmer's test, and subject satisfaction.

RESULTS

Patients reported an improvement (a significant decrease of -19.5%±27.5%) in OSDI scores after using Visaid 0.2% and a worsening (a significant increase of 19.2%±32.4%) after using 0.9% saline solution; the difference was significant (P=0.0087, Student's t test). Significant changes (P≤0.04, Wilcoxon's test) were found comparing Visaid 0.2% with saline solution for bulbar hyperemia (-39.1%±50.8% vs. 7.8%±12.0%, respectively), corneal staining (-26.0%±53.0% vs. 36.5%±73.3%), conjunctival staining (-54.7%±53.4% vs. -7.8%±47.2%), and subjective satisfaction (26.8%±28.5% vs. -13.3%±22.5%). There were no significant differences in the safety parameters for either solution.

CONCLUSION

This clinical trial demonstrates the safety of Visaid 0.2% and its clear benefit over 0.9% saline solution.

Comparison of 0.2% and 0.18% hyaluronate eye drops in patients with moderate to severe dry eye with keratitis or keratoconjunctivitis

PURPOSE

Comparison of efficacy and safety of 0.2% and 0.18% hyaluronic acid (HA) eye drops three times a day (tid) in patients with moderate to severe dry eye disease, related to keratitis or keratoconjunctivitis.

PATIENTS AND METHODS

Prospective, multicenter, randomized, single-masked, phase IIIb, noninferiority study (0.2% HA vs 0.18% HA) in two parallel groups over a period of 84 days. N=70 patients were evaluated. Primary efficacy outcome was ocular surface (OS) staining change on day 35 (D35), compared to baseline. Fluorescein and lissamine green were used for staining of cornea and conjunctiva. Secondary efficacy outcome included tear film breakup time, OS staining score on day 84 (D84), ocular comfort index, as well as patients' and doctors' evaluation.

RESULTS

Compared to day 0 (D0), 0.2% HA achieved a 47.7% reduction in staining score (-3.00±2.81 [standard deviation] points, n=38 patients) at D35; 0.18% HA showed a 41.2% reduction (-2.59±2.20 [standard deviation] points, n=32 patients). Statistical analysis showed noninferiority in efficacy of 0.2% HA compared to 0.18% HA on D35. At D84, the reduction in staining score had further increased to 64.5% for 0.2% HA and to 56.4% for 0.18% HA. Both eye drops improved tear film breakup time and ocular comfort index values. Investigators and patients assessed both treatments with 5 of 7 points (Likert Scale, medians). The rate of adverse events (AE) was 2.3% for 0.2% HA and 7.1% for 0.18% HA with no serious AE.

CONCLUSION

0.2% and 0.18% HA eye drops significantly improved signs and symptoms of dry eye disease and were well tolerated with few AEs. Noninferiority of 0.2% HA compared to 0.18% HA was demonstrated for reduction of OS lesions. In some parameters, there was a nonsignificant trend in favor of 0.2% HA concentration.

Efficacy of Carboxymethylcellulose and Hyaluronate in Dry Eye Disease: A Systematic Review and Meta-Analysis

Background

The efficacy of two artificial tears, carboxymethylcellulose (CMC) and hyaluronate (HA), was compared in the treatment of patients with dry eye disease.

Methods

We conducted a systematic review and meta-analysis on randomized controlled trials in the PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases. The efficacy was compared in terms of the mean change from baseline in tear break-up time. The meta-analysis was conducted using both random and fixed effect models. The quality of the selected studies was assessed for risk of bias.

Results

Five studies were included involving 251 participants. Random effect model meta-analysis showed no significant difference between CMC and HA in treating dry eye disease (pooled standardized mean difference [SMD]=-0.452; 95% confidence interval [CI], -0.911 to 0.007; P=0.053). In contrast, fixed effect model meta-analysis revealed significant improvements in the CMC group when compared to the HA group (pooled SMD=-0.334; 95% CI, -0.588 to -0.081; P=0.010).

Conclusion

The efficacy of CMC appeared to be better than that of HA in treating dry eye disease, although meta-analysis results were not statistically significant. Further research is needed to better elucidate the difference in efficacy between CMC and HA in treating dry eye disease.

Current Approach to Dry Eye Disease

Dry eye disease (DED) is a multifactorial disease of the tears and ocular surface that causes tear film instability with potential damage to the ocular surface. The prevalence of dry eye in the world population ranges from 6 to 34 %. It is more common in those aged over 50, and affects mainly women. Since the introduction of the Schirmer's test in 1903, other tests have been developed to evaluate dry eye, such as biomicroscopy, the tear film breakup time (BUT), vital dyes (lissamine green and rose bengal), fluorescein, leaf fern test, corneal sensitivity test, conjunctiva impression cytology, optical coherence tomography (OCT), and tear osmolarity measurement. Although there is no gold standard, it is advisable to combine at least two tests. Strategies for treating DED have recently been modified and include patient education, tear substitute, corticosteroids, secretagogues, fatty acids, immunomodulators, occlusion of lacrimal puncta surgery and, tarsorrhaphy. Biological therapy and new topical immunomodulators such as tacrolimus, tofacitinib and IL-1 receptor inhibitor are being tested. In this review, the evaluation tests for dry eye are compared and the main studies on treatment are presented, with emphasis on studies in patients with Sjögren's syndrome. The authors propose an approach for the management of dry eye.

Over the counter (OTC) artificial tear drops for dry eye syndrome

BACKGROUND

Over the counter (OTC) artificial tears historically have been the first line of treatment for dry eye syndrome and dry eye-related conditions like contact lens discomfort, yet currently we know little regarding the overall efficacy of individual, commercially available artificial tears. This review provides a much needed meta-analytical look at all randomized and quasi-randomized clinical trials that have analyzed head-to-head comparisons of OTC artificial tears.

OBJECTIVES

To evaluate the effectiveness and toxicity of OTC artificial tear applications in the treatment of dry eye syndrome compared with another class of OTC artificial tears, no treatment, or placebo.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2015, Issue 12), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to December 2015), EMBASE (January 1980 to December 2015), Latin American and Caribbean Health Sciences (LILACS) (January 1982 to December 2015), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en) and the US Food and Drugs Administration (FDA) website (www.fda.gov). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 4 December 2015. We searched reference lists of included trials for any additional trials not identified by the electronic searches.

SELECTION CRITERIA

This review includes randomized controlled trials with adult participants who were diagnosed with dry eye, regardless of race and gender. We included trials in which the age of participants was not reported, and clinical trials comparing OTC artificial tears with another class of OTC artificial tears, placebo, or no treatment. This review did not consider head-to-head comparisons of artificial tears with another type of dry-eye therapy.

DATA COLLECTION AND ANALYSIS

We followed the standard methodological procedures expected by Cochrane. Two authors independently screened the search results, reviewed full-text copies for eligibility, examined risk of bias, and extracted data. We performed meta-analysis for trials that compared similar interventions and reported comparable outcomes with sufficient data. We summarized all other included trial results in the text.

MAIN RESULTS

We included 43 randomized controlled trials (3497 participants with dry eye). Due to the heterogeneity of study characteristics among the included trials with respect to types of diagnostic criteria, interventions, comparisons, and measurements taken, our ability to perform meta-analyses was limited. The review found that, in general, there was uncertainty whether different OTC artificial tears provide similar relief of signs and symptoms when compared with each other or placebo. Nevertheless, we found that 0.2% polyacrylic acid-based artificial tears were consistently more effective at treating dry eye symptoms than 1.4% polyvinyl alcohol-based artificial tears in two trials assessing this comparison (175 participants). All other included artificial tears produced contradictory between-group results or found no between-group differences. Our review also found that OTC artificial tears may be generally safe, but not without adverse events. Overall, we assessed the quality of evidence as low due to high risks of bias among included trials and poor reporting of outcome measures which were insufficient for quantitative analysis. Furthermore, we identified an additional 18 potentially eligible trials that were reported only in clinical trial registers with no associated results or publications. These trials reportedly enrolled 2079 total participants for whom no data are available. Such lack of reporting of trial results represents a high risk of publication bias.

AUTHORS' CONCLUSIONS

OTC artificial tears may be safe and effective means for treating dry eye syndrome; the literature indicates that the majority of OTC artificial tears may have similar efficacies. This conclusion could be greatly skewed by the inconsistencies in study designs and inconsistencies in reporting trial results. Additional research is therefore needed before we can draw robust conclusions about the effectiveness of individual OTC artificial tear formulations.

The pathophysiology, diagnosis, and treatment of dry eye disease

BACKGROUND

Dry eye disease (DED) is common; its prevalence around the world varies from 5% to 34%. Its putative pathogenetic mechanisms include hyperosmolarity of the tear film and inflammation of the ocular surface and lacrimal gland. Dry eye is clinically subdivided into two subtypes: one with decreased tear secretion (aqueous-deficient DED), and one with increased tear evaporation (hyperevaporative DED).

METHODS

This review is based on pertinent publications retrieved by a selective PubMed search and on the authors' own clinical and scientific experience.

RESULTS

The diagnostic evaluation of dry eye disease should include a detailed patient history, thorough split-lamp examination, and additional tests as indicated. Few randomized controlled therapeutic trials for dry eye have been published to date. Artificial tears of various kinds are recommended if the symptoms are mild. Lid hygiene is helpful in the treatment of hyperevaporative dry eye, while collagen or silicon plugs can be used for partial occlusion of the efferent lacrimal ducts to treat severe hyposecretory dry eye. The benefit of long-term topical anti-inflammatory treatment of moderate or severe dry eye disease with corticosteroids or cyclosporine A eye drops has been documented in clinical trials on a high evidence level. Orally administered tetraycycline derivatives and omega-3 or omega-6 fatty acids are also used.

CONCLUSION

The treatment of dry eye has evolved from tear substitution alone to a rationally based therapeutic algorithm. Current research focuses on pathophysiology, new diagnostic techniques, and novel therapies including secretagogues, topical androgens, and new anti- inflammatory drugs.