Patient-Reported Dry Eye Treatment and Burden of Care.

OBJECTIVES: Dry eye is a common condition that can decrease the quality of life. This survey-based study of persons with dry eye investigated self-reported treatments (initial, current), out-of-pocket expenses, time spent on self-management, sources of care, and sources of information about their condition. METHODS: Online dry eye newsletters and support groups were emailed a link to an electronic survey asking members to participate. Survey respondents were not required to answer every question. RESULTS: In total, 639 persons with self-reported dry eye responded (86% women, 14% men [n=623]; mean ± SD age, 55 ± 14 years [n=595]). Artificial tears were the most reported intervention (76% initially, 71% currently). The median (interquartile range) out-of-pocket treatment cost annually was $500 ($200-$1,320 [n=506]). In addition, 55% (n=544) estimated 5 to 20 min daily on self-management; 22% spent an hour or more. Ophthalmologists provided most dry eye care (67%, n=520). Only 48% (n=524) reported that their primary source of dry eye information came from their eye care clinician. CONCLUSIONS: Artificial tears are the primary treatment for dry eye. Ophthalmologists provide most dry eye care, but half of patients report that their eye care provider is not their primary source of information. Almost one fourth of patients spend an hour or more daily on treatments.

Perioperative intense pulsed light to prevent and improve symptoms of post-laser corneal refractive surgery dry eye. A randomized clinical trial.

PURPOSE: To evaluate the efficacy of perioperative IPL therapy in preventing postoperative ocular surface disorders in patients undergoing corneal laser refractive surgery. DESIGN: randomized, controlled, clinical trial with triple-blinding. METHODS: Setting: Vissum Miranza - Alicante; Study population: 61 patients randomized in two groups: 31 study patients (perioperative IPL + laser refractive surgery) and 30 control patients (perioperative placebo + laser refractive surgery). Follow-up was conducted over a 6-month period; Intervention: Each participants underwent three IPL sessions with a two-week interval between each session (pre-surgery, post-surgery week-one, and post-surgery week-three). For controls, placebo was administered following the same protocol. MAIN OUTCOMES MEASURES: visual outcomes and refraction, slit-lamp examination, corneal topography, visual analogue scale questionnaire and Oculus Keratograph 5 M including tear meniscus height, non-invasive tear break- up time, ocular redness, infrared meibography and Ocular Surface Disease Index (OSDI) questionnaire. RESULTS: 61 randomized eyes were included. No significant differences were observed in terms of uncorrected and corrected distance visual acuity (UDVA, CDVA), refractive error or corneal aberrations. A statistically significant improvement in OSDI score (change -8.47, p = 0.043), tear meniscus (change 0.05 mm, p = 0.004) and Meibography (change -0.42, p = 0.012) was observed at the third postoperative month in the study group. Additionally, at the sixth postoperative month, there were statistically significant improvements in tear meniscus (change 0.06 mm, p = 0.018), tear break-up-time (change 1.68 s, p = 0.039) and Meibography (change -0.37, p = 0.030). CONCLUSIONS: Results suggest that perioperative IPL therapy applied to laser corneal refractive surgery improves objective and subjective ocular surface parameters over non-IPL-treated control patients and early postoperative dry eye symptoms.

Assessing clinical and molecular outcomes of prophylactic thermal pulsation therapy on ocular surface health following refractive surgery.

Purpose: To study ocular surface signs, symptoms, and tear film composition following prophylactic thermal pulsation therapy (TPT) prior to refractive surgery, and to compare these outcomes with those who underwent TPT after refractive surgery. Methods: Patients with mild-to-moderate evaporative dry eye disease (DED) and/or meibomian gland dysfunction (MGD) undergoing refractive surgery were included. Group 1 patients received TPT (LipiFlow) prior to laser-assisted in situ keratomileusis (LASIK; n = 32, 64 eyes), and Group 2 patients received TPT three months after LASIK (n = 27, 52 eyes). Ocular Surface Disease Index (OSDI) score, Schirmer's test (ST1, ST2), Tear Breakup Time (TBUT), meibography, and tear fluid were obtained preoperatively and at three months postoperatively in Groups 1 and 2. Additional postoperative evaluation was performed three months after TPT in Group 2. Tear soluble factor profile was measured by multiplex enzyme-linked immunosorbent assay (ELISA) using flow cytometry. Results: Postoperative OSDI score was significantly lower and TBUT was significantly higher when compared with matched preoperative values of Group 1 participants. On the other hand, the postoperative OSDI score was significantly higher and TBUT significantly lower when compared with matched preoperative values of Group 2 participants. TPT significantly reduced the postoperative elevation in OSDI and significantly reduced the postoperative reduction in TBUT in Group 2 participants. Tear Matrix metalloproteinase-9/ Tissue inhibitor matrix metalloproteinase 1 (MMP-9/TIMP1) ratio was significantly higher, postoperatively, when compared with matched preoperative levels in Group 2. However, MMP9/TIMP1 ratio remained unaltered in Group 1 participants. Conclusion: TPT prior to refractive surgery improved postsurgical ocular surface signs and symptoms and reduced tear inflammatory factors, thereby suggesting the plausibility of reduced post-refractive surgery DED in patients.

Dynasore Protects Corneal Epithelial Cells Subjected to Hyperosmolar Stress in an In Vitro Model of Dry Eye Epitheliopathy.

Epitheliopathy at the ocular surface is a defining sign of dry eye disease, a common disorder that affects 10% to 30% of the world's population. Hyperosmolarity of the tear film is one of the main drivers of pathology, with subsequent endoplasmic reticulum (ER) stress, the resulting unfolded protein response (UPR), and caspase-3 activation implicated in the pathway to programmed cell death. Dynasore, is a small molecule inhibitor of dynamin GTPases that has shown therapeutic effects in a variety of disease models involving oxidative stress. Recently we showed that dynasore protects corneal epithelial cells exposed to the oxidant tBHP, by selective reduction in expression of CHOP, a marker of the UPR PERK branch. Here we investigated the capacity of dynasore to protect corneal epithelial cells subjected to hyperosmotic stress (HOS). Similar to dynasore's capacity to protect against tBHP exposure, dynasore inhibits the cell death pathway triggered by HOS, protecting against ER stress and maintaining a homeostatic level of UPR activity. However, unlike with tBHP exposure, UPR activation due to HOS is independent of PERK and mostly driven by the UPR IRE1 branch. Our results demonstrate the role of the UPR in HOS-driven damage, and the potential of dynasore as a treatment to prevent dry eye epitheliopathy.

Effect of facemasks on the tear film during the COVID-19 pandemic.

PURPOSE: To evaluate the effect of wearing facemasks on dry eye symptoms and on the tear film while comparing surgical face masks to N95 particulate respirators. METHODS: A prospective observational study was conducted at Ain Shams University Hospitals in the period from September 2020 to January 2021. Two hundred volunteers were recruited, and the daily number of hours spent by each participant wearing a facemask was recorded. Recruits were divided into two groups: 100 volunteers were allocated to Group A to use the surgical mask, and 100 participants to Group B to use the N95 particulate respirator. The tear film parameters were assessed at baseline by answering the Ocular Surface Disease Index (OSDI) questionnaire and performing tear break-up time (TBUT), corneal fluorescein staining, and Schirmer-I test Subjects then wore a facemask for 60 min and then the tear film parameters were reassessed by repeating TBUT, corneal staining and Schirmer-I test. RESULTS: Facemask use for 60 min significantly worsened all tear film parameters in both groups (P-value <0.0001). The deterioration was significantly larger in Group A subjects (P < 0.0001). The daily number of hours spent wearing a facemask correlated strongly with the OSDI and corneal staining. There was a strong negative correlation between the daily number of hours spent wearing a facemask and Schirmer test, and a weak negative correlation with TBUT. CONCLUSIONS: Wearing facemasks during the COVID-19 pandemic is a risk factor for worsening tear film parameters. This deterioration is significantly greater with surgical masks than with N95 particulate respirators and increases with the duration of facemask use.

The effect of eye care protocol on the prevention of ocular surface disorders in patients admitted to intensive care unit.

Eye care is one of the most critical tasks of intensive care unit (ICU) nurses. Patients in this unit are exposed to potential ocular problems due to critical conditions. This study aimed to establish a new eye care protocol for preventing ocular surface disorders in patients admitted to ICU. This was a clinical trial study performed on patients admitted to ICU in 2019. The data gathering tools included the demographic questionnaire, the Schirmer test for dry eye, fluorescein staining and slit lamp manual for examining corneal ulcers, and slit lamp manual to check keratitis and conjunctivitis. A type of eye care protocol was performed on the patient's eyes. After five consecutive days of executing the protocol, the data were analyzed using SPSS software version 18. The use of eye care protocol reduced the risk of keratitis (P=0.027), conjunctivitis (P=0.012), eye dryness (P=0.001), and corneal ulcer (P=0.003) in patients admitted to ICU in the intervention group compared to the control group. Ophthalmology protocols reduced the incidence of keratitis, conjunctivitis, dry eye, and corneal ulcers in ICU patients. Therefore, using this method in ICU patients can improve nursing care.

Determining the Best Management Strategy for Preventing Short-Term Effects of Digital Display Use on Dry Eyes.

OBJECTIVES: To assess and compare the effectiveness of four main management strategies for preventing short-term effects of digital display use on dry eye signs and symptoms. METHODS: The ocular surface, tear film, and visual fatigue of 47 healthy individuals were assessed before and after reading on a laptop computer for 20 min under five different experimental conditions: control, instillation of artificial tears, taking a brief break, using a blue light screen filter, and blink control. Measurements included the Ocular Surface Disease Index (OSDI) Questionnaire, 5-item Dry Eye Questionnaire (DEQ-5), tear meniscus height (TMH), noninvasive keratograph break-up time (NIKBUT), bulbar conjunctival redness, and pupil size. RESULTS: Worse results were obtained after the control and blue light filter conditions in all variables (P≤0.037). A higher post-task DEQ-5 score (P=0.013) and TMH (P<0.0005) were obtained when taking a brief break compared with pretask, although the increase in symptoms was significantly smaller than that observed in the nonmanagement control condition (P≤0.036). Similarly, a smaller increase in OSDI and DEQ-5 was obtained with the use of artificial tears and blink control in comparison with the control condition (P≤0.008), whereas a greater increase in DEQ-5 and decrease in NIKBUT was obtained for the blue light filter condition in comparison with the instillation of artificial tears (P=0.017) or blink control (P=0.008), respectively. Finally, a significantly lower post-task pupil size was obtained for all the conditions (P≤0.027). CONCLUSIONS: The instillation of artificial tears and blink control were the best management strategies for preventing short-term effects of digital display use on dry eyes. Conversely, using a blue light filter did not offer any benefits.

Prevention of localized corneal hyperosmolarity spikes by soft-contact-lens wear.

PURPOSE: To determine whether localized hyperosmotic spikes on the pre-lens tear film (PrLTF) due to tear break up results in hyperosmotic spikes on the ocular surface during soft-contact-lens (SCL) wear and whether wear of SCLs can protect the cornea against PrLTF osmotic spikes. METHODS: Two-dimensional transient diffusion of salt was incorporated into a computationally designed SCL, post-lens tear film (PoLTF), and ocular surface and solved numerically. Time-dependent localized hyperosmolarity spikes were introduced at the anterior surface of the SCL corresponding to those generated in the PrLTF. Salt spikes were followed in time until spikes penetrate through the lens into the PoLTF. Lens-salt diffusivities (Ds) were varied to assess their importance on salt migration from the PrLTF to the ocular surface. SCL and PoLTF initial conditions and the lens anterior-surface boundary condition were varied depending on the value of Ds and on dry-eye symptomatology. Determined corneal surface osmolarities were translated into clinical pain scores. RESULTS: For Ds above about 10-7cm2/s, it takes around 5-10 s for the PrLTF hyperosmotic break-up spikes to diffuse across the SCL and reach the corneal surface. Even if localized hyperosmotic spikes penetrate to the ocular surface, salt concentrations there are much lower than those in the progenitor PrLTF spikes. For Ds less than 10-7cm2/s, the SCL protects the cornea from hyperosmotic spikes for both normal and dry eyes. When localized corneal hyperosmolarity is converted into transient pain scores, pain thresholds are significantly lower than those for no-lens wear. CONCLUSIONS: A cornea can be protected from localized PrLTF hyperosmolarity spikes with SCL wear. With regular blinking (e.g., less than 10 s), SCL wear shields the cornea from significant hyperosmotic pain. Decreasing Ds increases that protection. Low-Ds soft contact lenses can protect against hyperosmotic spikes and discomfort even during infrequent blinking (e.g., > 10 s).

The effect of day-long mask wearing on non-invasive break-up time.

PURPOSE: This study aimed to investigate the effect of day-long face mask wearing on non-invasive tear break-up time (NI-BUT) in health care staff due to working schedules. METHODS: Seventy-four right eyes of 74 participants were included in the study. Participants completed the Ocular Surface Disease Index (OSDI) questionnaire, and NI-BUT measurements were performed between 08.30-09.00 and 16.30-17.00 h. Participants with an initial NI-BUT measurement below 17 s were classified as group-1, and those over 17 s were classified as group-2. NI-BUT changes during the day and correlation to age, gender, and OSDI results were evaluated. RESULTS: Thirty-eight women and 36 men, with a mean age of 30.9 ± 8.5 years, were included in the study. The mean OSDI score of the participants was 28.6 ± 17.1. NI-BUT means of group-1 at baseline and 8th hour were 11.4 ± 3.3 and 7.9 ± 3.6 s, respectively, and the mean NI-BUT at the 8th hour was statistically significantly lower than the baseline (p < 0.0001). Also, 24.2% (8 people) of those in group-2 had the 8th-hour NI-BUT value fallen into the measurable range (below 17 s). No significant correlation was found between the decrease in NI-BUT value and age, gender, and OSDI (p = 0.08, p = 0.3, and p = 0.2, respectively). CONCLUSION: The use of face masks throughout the day leads to a significant reduction in NI-BUT, regardless of age, gender, and OSDI score. Prolonged use of face masks should be considered as a risk factor for evaporative dry eye disease.

Protection against corneal hyperosmolarity with soft-contact-lens wear.

Hyperosmotic tear stimulates human corneal nerve endings, activates ocular immune response, and elicits dry-eye symptoms. A soft contact lens (SCL) covers the cornea preventing it from experiencing direct tear evaporation and the resulting blink-periodic salinity increases. For the cornea to experience hyperosmolarity due to tear evaporation, salt must transport across the SCL to the post-lens tear film (PoLTF) bathing the cornea. Consequently, limited salt transport across a SCL potentially protects the ocular surface from hyperosmotic tear. In addition, despite lens-wear discomfort sharing common sensations to dry eye, no correlation is available between measured tear hyperosmolarity and SCL-wear discomfort. Lack of documentation is likely because clinical measurements of tear osmolarity during lens wear do not interrogate the tear osmolarity of the PoLTF that actually overlays the cornea. Rather, tear osmolarity is clinically measured in the tear meniscus. For the first time, we mathematically quantify tear osmolarity in the PoLTF and show that it differs significantly from the clinically measured tear-meniscus osmolarity. We show further that aqueous-deficient dry eye and evaporative dry eye both exacerbate the hyperosmolarity of the PoLTF. Nevertheless, depending on lens salt-transport properties (i.e., diffusivity, partition coefficient, and thickness), a SCL can indeed protect against corneal hyperosmolarity by reducing PoLTF salinity to below that of the ocular surface during no-lens wear. Importantly, PoLTF osmolarity for dry-eye patients can be reduced to that of normal eyes with no-lens wear provided that the lens exhibits a low lens-salt diffusivity. Infrequent blinking increases PoLTF osmolarity consistent with lens-wear discomfort. Judicious design of SCL material salt-transport properties can ameliorate corneal hyperosmolarity. Our results confirm the importance of PoLTF osmolarity during SCL wear and indicate a possible relation between PoLTF osmolarity and contact-lens discomfort.

Corneal protective effects of novel tear substitutes containing sodium hyaluronate and dodecahydrosqualene, squalane, in a porcine dry eye model.

To develop a novel tear substitute (TS) containing sodium hyaluronate (SH) and dodecahydrosqualene (DHS, squalane), we improved the prescription of a previously developed TS containing saline, 0.5% SH and 1% castor oil (CO), which had corneal protective effects against 60-min desiccation in a porcine dry eye model and viscosity of 106.8 mPa·S. Fresh porcine eyes were treated with a TS containing saline, 0.1%, 0.25%, 0.3% or 0.5% SH, and 1% CO or 1%, 2.5% or 5% DHS, and TS-treated eyes were desiccated for up to 180 min. The corneal damage was evaluated by the staining score of methylene blue (MB), absorbance of MB extracted from the cornea, the staining density of lissamine green (LG) and histopathology. The viscosities of the examined TS were also measured. A saline/0.5% SH/1% DHS solution had corneal protective effects for 90 min under desiccation and a viscosity of 110.0 mPa·s. A TS with saline, 0.1%, 0.25% or 0.3% SH and 1% or 2.5% DHS did not have better protective effects than a saline/0.5% SH/1% DHS solution, although a saline/0.3% SH/5% DHS solution exhibited greater corneal protection against 180-min desiccation on MB and LG staining and histopathological examination, and its viscosity was 34.5 mPa·s, which was similar to the 29.5 mPa·s of 0.3% SH. The saline/0.3% SH/5% DHS solution is available as a novel 3-hr long-lasting TS containing mucinomimetic and liquid oil components to treat and relieve dry eye symptoms in animals and humans.

Improving ocular surface comfort in contact lens wearers.

PURPOSE: Contact lens discomfort (CLD) is a major concern that can lead to the decreased or abandoned use of contact lenses. Contact lens users with dry eye disease are more likely to present with CLD. This study was conducted to evaluate the efficacy of a bioprotective preservative free, hypotonic, 0.15% hyaluronic acid (HA)-3% Trehalose artificial tear in managing dry eye symptoms in contact lens wearers. METHODS: A prospective, single-arm, observational pilot study to evaluate the effectiveness of treatment with HA-Trehalose artificial tears in contact lens wearers (N = 33) aged 18-45 years with symptoms of ocular discomfort. Participants used a preservative-free, hypotonic HA-Trehalose artificial tear (1 drop/4 times per day) for 84 days. Participants were assessed using Visual Analogue Scale (VAS) for dry eye symptoms (pain, photophobia, dry eye sensation, blurry vision, foreign body sensation, itching, tingling/burning, and sticky eye feeling), Ocular Surface Disease Index (OSDI), Contact Lens Dry Eye questionnaire (CLDEQ-8), Berkley Dry Eye Flow-Chart (DEFC) on Day 0 and Day 84 and tear break-up time (TBUT), ocular surface staining with fluorescein and lissamine green, tear meniscus evaluation, and visual acuity on Day 0, 35, and 84. RESULTS: All VAS symptoms (except tingling/burning and sticky eye feeling), OSDI, CLEDQ-8, and DEFC showed statistically significant (p < 0.05) improvement from baseline (Day 0) to Day 84. Similarly, corneal (fluorescein) and conjunctival (lissamine green) quality improved during the study (p < 0.05 at Day 84 versus baseline). Tear break-up time (TBUT), conjunctival (lissamine green) staining, and tear meniscus decreased but the changes were not statistically significant. Visual acuity did not change during the study. There were no ocular or systemic adverse events. CONCLUSIONS: This study showed that the instillation of a preservative-free, hypotonic, HA-Trehalose artificial tear in contact lenses wearers with dry eye syndrome significantly improved symptoms and reduced associated signs such as corneal and conjunctival staining.

Digital asthenopia: blue-blocking lenses and + 0,40D additional power in the near zone, for eye strain, accommodation and convergence functions / Astenopia digital: avaliação de lentes com filtro de luz azul e poder adicional de +0,40D na zona de perto, para fadiga visual e nas funções de convergência e acomodação

ABSTRACT Purpose Evaluate blue-violet light filter and additional power of +0.40 D in the near zone ophthalmic lenses, on convergence, accommodative functions, and symptoms of digital asthenopia (DA). Methods Randomized study in cross-over design conducted on 49 volunteers (age, 29 ± 5.5 years; male: female, 18:31). Each subject wore test (+0.40 D in the near zone) and control lenses (regular single vision) for 4 weeks in randomized order. Both lenses had a selective blue-violet light filter. A baseline measurement was taken with the subjects' current updated glasses. Accommodation amplitude (AA) and near point of convergence (NPC) were measured binocularly with the RAF ruler. DA was evaluated by a questionnaire. Results No significant difference (p=.52) was found for AA comparing baseline (11.50±1.88 D), test (11.61± 1.62 D), and control SV lenses (11.88±1.50 D). No significant difference was found for NPC (p=.94), between baseline (6.50 ± 2.89cm), test (6.71± 3.49) and control SV lenses (6.82± 3.50 cm). No significant difference was found comparing test and control SV lenses in symptoms of DA (p=0.20). Conclusions The +0.40 D lenses have no negative impact on convergence or loss of accommodation power. The +0.40 D and control SV lenses had a similar impact on attenuating symptoms of DA.

RESUMO Objetivo Avaliar os efeitos do uso de lentes oftálmicas com filtro seletivo de luz azul-violeta, sem e com poder adicional de + 0,4D na zona de perto nas funções de acomodação e convergência e para sintomas de astenopia digital (AD). Métodos Ensaio clínico controlado, randomizado e mascarado, com 49 voluntários (idade, 29 ± 5,5 anos; masculino: feminino, 18: 31). Cada participante usou lentes de teste (+0,40 D na zona de perto) e controle (visão simples), por 4 semanas de forma randomizada. Ambas as lentes tinham filtro seletivo de luz azul-violeta. A medição inicial (baseline) foi feita com os óculos atualizados de cada participante. A amplitude de acomodação (AA) e o ponto de convergência próximo (PPC) foram medidos binocularmente com a régua RAF. A AD foi avaliada por um questionário. Resultados Não houve diferença estatisticamente significante (p=0,52) para as medidas de AA comparando as lentes baseline (11,50±1,88 D), teste (11,61±1,62 D) e controle VS (11,88±1,50 D). Nenhuma diferença significativa foi encontrada para a medida do PPC (p=0,94), entre as lentes baseline (6,50 ± 2,89cm), teste (6,71±3,49) e controle VS (6,82±3,50 cm). Nenhuma diferença significativa foi encontrada comparando lentes teste de VS e controle nos sintomas de AD (p=0,20). Conclusões As lentes com +0,40 D não têm impacto negativo na convergência ou na perda de acomodação. As lentes +0,40 D e controle VS, tiveram impacto semelhante na redução dos sintomas de AD.

Efficacy of topical cyclosporine 0.05% and osmoprotective lubricating eye drops in treating dry eye disease and inflammation.

PURPOSE: To evaluate the effect of topical cyclosporine 0.05% and osmoprotective lubricating eye drops on patients with dry eye disease (DED) with inflammation as measured by raised tear matrix metalloproteinases (MMP-9). METHODS: This prospective study included 106 eyes of 53 patients diagnosed with DED based on any of the following DED criteria (Ocular Surface Disease Index [OSDI] score >12, tear film breakup time [TBUT] <10 s, Schirmer's I test result <10 mm/5 min, ocular surface staining). Ocular surface inflammation was assessed by assessing MMP-9 positivity from tears of the patients in the study (Inflammadry kit Quidel corporation). Patients were prescribed osmoprotective lubricating eye drops (Osmodrops, Cipla Ltd) four times a day and cyclosporine A 0.05% eye drops (Imudrops, Cipla Ltd) twice a day for 6 months. Efficacy of the formulations was evaluated by OSDI scores, Schirmer's test, TBUT change, reduction in ocular surface staining, and reduction in MMP-9 levels after 6 months of usage. Check P value and add from results. RESULTS: After 6 months of topical therapy, improvement was observed in OSDI scores (mean pretreatment: 25.7 ± 12.8, and mean posttreatment: 15.2 ± 8.4), P < 0.001. There was also reduction number of patients who were MMP-9 positive. Out of 75 eyes that tested MMP-9 positive, 70.66% showed reduction in MMP-9 levels P < 0.0001). Ocular surface staining also improved. CONCLUSION: Topical osmoprotective lubricating eye drops and cyclosporine A 0.05% reduce inflammation in cases of DED, which correlates with improvement in OSDI scores, ocular surface staining, and reduction in inflammation as measured by levels of tear MMP-9.

Optogenetic Inhibition of Nav1.8 Expressing Corneal Afferents Reduces Persistent Dry Eye Pain.

Purpose: The aim of the present study was to investigate the contribution of Nav1.8 expressing corneal afferent neurons to the presence of ongoing pain in lacrimal gland excision (LGE)-induced dry eye. Methods: The proton pump archaerhodopsin-3/eGFP (ArchT/eGFP) was conditionally expressed in corneal afferents using Nav1.8-cre mice. Dry eye was produced by unilateral LGE. Real time place preference was assessed using a three-chamber apparatus. A neutral, unlit center chamber was flanked by one illuminated with a control light and one illuminated with an ArchT activating light. For real-time preference, animals were placed in the neutral chamber and tracked over five 10-minute sessions, with the lights turned on during the second and fourth sessions. In other studies, movement was tracked over three 10-minute sessions (the lights turned on only during the second session), with animals tested once per day over the course of 4 days. A local anesthetic was used to examine the role of ongoing corneal afferent activity in producing place preference. Results: The corneal afferent nerves and trigeminal ganglion cell bodies showed a robust eGFP signal in Nav1.8-cre;ArchT/eGFP mice. After LGE, Nav1.8-cre;ArchT/eGFP mice demonstrated a preference for the ArchT activating light paired chamber. Preference was prevented with pre-application to the cornea of a local anesthetic. Nav1.8-cre;ArchT/eGFP mice with sham surgery and LGE wild-type control mice did not develop preference. Conclusions: Results indicate LGE-induced persistent, ongoing pain, driven by Nav1.8 expressing corneal afferents. Inhibition of these neurons represents a potential strategy for treating ongoing dry eye-induced pain.

Protective effects of low-molecular-weight components of adipose stem cell-derived conditioned medium on dry eye syndrome in mice.

The present study demonstrated the protective effects of low-molecular-weight adipose-derived stem cell-conditioned medium (LADSC-CM) in a mouse model of dry eye syndrome. Mice subjected to desiccating stress and benzalkonium chloride had decreased tear secretion, impaired corneal epithelial tight junction with microvilli, and decreased conjunctival goblet cells. Topical application of adipose-derived stem cell-conditioned medium (ADSC-CM) stimulated lacrimal tear secretion, preserved tight junction and microvilli of the corneal epithelium, and increased the density of goblet cells and MUC16 expression in the conjunctiva. The low-molecular-weight fractions (< 10 kDa and < 3 kDa) of ADSC-CM (LADSC-CM) provided better protections than the > 10 kDa or > 3 kDa fractions of ADSC-CM. In the in vitro study, desiccation for 10 min or hyperosmolarity (490 osmols) for 24 h caused decreased viability of human corneal epithelial cells, which were reversed by LADSC-CM. The active ingredients in the LADSC-CM were lipophobic and stable after heating and lyophilization. Our study demonstrated that LADSC-CM had beneficial effects on experimental dry eye. It is worthy of further exploration for the active ingredient(s) and the mechanism.

The effects of a steam warming eye mask on the ocular surface and mental health.

PURPOSE: The continuous use of warming eye masks improves tear function. In this double-blind randomized controlled trial, we aimed to analyze the effects of warming eye mask use on the ocular surface and mental health. METHODS: We enrolled 86 participants (age range: 23-89 years) from affiliated institutions who were divided into two groups: the warm group that used warming eye masks that generate moist heat at 40 °C for 10 min and the control group that used non-warming eye masks. The participants used the masks for 10 min once daily for 2 weeks. Before and after the intervention, in 79 participants (warm group 39, control group 40), we analyzed the tear break up time (TBUT) and corneal and conjunctival fluorescein staining results in the right eye and Hospital Anxiety and Depression Score (Anxiety: HADS-A, Depression: HADS-D), and Subjective Happiness Scale (SHS) questionnaires. The parameters before and after the intervention were compared via paired-t tests. RESULTS: The following variables changed after the intervention: TBUT (warm group: 1.4 ± 2.1 s vs. control group: -0.01 ± 2.38 s), fluorescein staining score (-0.7 ± 1.1 vs.-0.2 ± 1.1), HADS-A (-0.8 ± 3.1 vs. -0.2 ± 2.2), and HADS-D (-1.0 ± 2.4 vs. -0.4 ± 1.9). Significant changes were observed in the TBUT (warm group), fluorescein staining score (warm group), and HADS-D (warm group). CONCLUSIONS: Using a warming eye mask improves not only the ocular surface conditions but also the subjective depression scores.

Polyethylene eye-cover versus artificial teardrops in the prevention of ocular surface diseases in comatose patients: A prospective multicenter randomized triple-blinded three-arm clinical trial.

BACKGROUND: Polyethylene covers are claimed to be useful in preventing ocular surface diseases (OSD); however, evidence of their clinical efficacy is limited. This clinical trial aimed to compare the use of polyethylene eye covers and artificial teardrops versus normal saline on the incidence and severity of OSD in comatose patients. METHODS: Of 90 eligible patients randomly assigned to three treatment groups, 79 patients completed the study, In group A, patients (n = 25) received artificial teardrops for left and normal saline for right eyes, in group B (n = 29) polyethylene covers for left and normal saline for right eyes, and in group C (n = 25) polyethylene covers for left and artificial teardrops for right eyes. As the patients were comatose, their blinding did not applicable, and a blinded observer evaluated the patients' eyes based on the Corneal Fluorescein Staining Pattern. The blinded analyzer analyzed collected data by SPSS-16 software at a 95% confidential level. RESULTS: The OSDs were observed in 65 (41.14%) out of 158 eyes examined. The artificial teardrop was more effective than the normal saline in group A, polyethylene eye cover was more useful than the normal saline in group B, and polyethylene eye cover was more effective than the artificial teardrop in group C in reducing the incidence of OSD (p< 0.01). Polyethylene eye covers had the most impact on reducing the severity of the OSD compared to the other interventions (p< .001). CONCLUSIONS: Polyethylene eye covers significantly reduced the incidence and severity of OSD. Using polyethylene cover is suggested as a safe, effective, and accessible eye care intervention for preventing OSD in comatose patients. TRIAL REGISTRATION: (IRCT201609129014N115), Iranian Registry of Clinical Trials.

Randomized, crossover clinical efficacy trial in humans and mice on tear secretion promotion and lacrimal gland protection by molecular hydrogen.

The incidence of dry eye disease is increasing worldwide because of the aging population and increasing use of information technology. Dry eye disease manifests as tear-layer instability and inflammation caused by osmotic hypersensitization in tear fluids; however, to our knowledge, no agent that treats both pathologies simultaneously is available. Molecular hydrogen (H2) is known to be effective against various diseases; therefore, we aimed to elucidate the effects of H2 on tear dynamics and the treatment of dry eye disease. We revealed that administering a persistent H2-generating supplement increased the human exhaled H2 concentration (p < 0.01) and improved tear stability (p < 0.01) and dry eye symptoms (p < 0.05) significantly. Furthermore, H2 significantly increased tear secretion in healthy mice (p < 0.05) and significantly suppressed tear reduction in a murine dry eye model (p = 0.007). H2 significantly and safely improved tear stability and dry eye symptoms in a small exploratory group of 10 human subjects, a subset of whom reported dry eye symptoms prior to treatment. Furthermore, it increased tear secretion rapidly in normal mice. Therefore, H2 may be a safe and effective new treatment for dry eye disease and thus larger trials are warranted.