Instillation Of Artificial Tears Research Articles

Evaluation of changes in lacrimal canaliculi width depending on temperature and viscosity of eye drops using spectral-domain optical coherence tomography in dogs.

To evaluate the changes in the width of the lower lacrimal canaliculi (LC) upon instillation of artificial tears (AT) at different temperatures and viscosities using spectral-domain optical coherence tomography (SD-OCT). Eight eyes of four client-owned adult dogs. Imaging of lower LC was performed under general anesthesia. AT at temperatures of 2°C, 20°C, and 38°C, and a high-viscosity tear gel of 20°C, were topically instilled in 100 μL volumes. SD-OCT tracked LC width changes following each instillation. The average baseline width of the LC was 96.38 ± 30.18 μm. The 2°C AT expanded LC width to 183.50 ± 44.11 μm, returning to baseline in 5.00 ± 1.31 min. The 20°C AT resulted in a width of 155.25 ± 35.79 μm, with a 3.88 ± 1.25 min return. The 38°C AT expanded LC width to 131.75 ± 29.49 μm, with a 2.25 ± 0.89 min return. The high-viscosity tear gel expanded LC width to 208.57 ± 56.31 μm, with remained expanded for 10 or more minutes. In temperature comparisons, the 2°C and 20°C AT significantly expanded the LC width more and had longer return times than the 38°C AT (p < .05). Viscosity comparisons showed higher viscosity eye drops significantly expanded LC width more than lower viscosity eye drops (p < .05). This study found that lower temperature and higher viscosity of eye drops had tendency to result in a wider expansion of the LC width. Additionally, the return time to baseline for LC width tended to be longer with eye drops of lower temperature and higher viscosity. This finding could be helpful in advancing future research on tear dynamics.

Efficacy and safety of artificial tears containing Artemia salina extract with dinucleotides for dry eye

ABSTRACT Clinical relevance This clinical trial was conducted as part of the marketing procedures for a medical device comprising artificial tears containing Artemia salina extract with dinucleotides. These molecules previously demonstrated secretagogue properties by enhancing the production of aqueous, mucinous, and lipidic components of the tears. Background After confirming the efficacy of artificial tears containing Artemia salina extract in an animal model, this study proceeded to evaluate their efficacy and safety on dry eye participants. Methods A randomised controlled clinical trial was performed on 36 dry eye participants (41.6 ± 20.6 years). Half of the participants were treated with saline solution as a placebo for four weeks, while the other half were treated with artificial tears containing Artemia salina, randomly assigned. After a wash-out period of two weeks, the treatments were crossed for another four weeks. Participants were assessed at baseline and after one week, two weeks, and four weeks. Efficacy variables were: eye dryness frequency (primary), eye comfort, visual satisfaction, tear secretion, tear break-up time, corneal staining, conjunctival staining, and conjunctival hyperaemia. Safety variables were: high- and low-contrast visual acuity, intraocular pressure, and eye fundus images analysis. Results Compared with the baseline, the saline solution showed no significant changes in any of the studied variables after four weeks of treatment (p ≥ 0.05). However, the topical instillation of the artificial tears with Artemia salina for four weeks significantly improved eye dryness frequency (p = 0.014) and corneal staining (p = 0.010). No systemic or ocular adverse events were reported during the clinical trial. Conclusion The topical instillation of artificial tears containing Artemia salina in mild to moderate dry eye participants for four weeks slightly improved their symptoms related to eye dryness frequency and reduced corneal damage, with no undesirable side effects observed.

Ocular surface changes following computer use in post-LASIK patients.

To assess the impact of computer use on the ocular surface of individuals after laser insitu keratomileusis (LASIK). The dry eye symptoms and ocular surface of 18 post-LASIK young individuals and 18 controls were evaluated before and after performing a 30-min task on a computer without (Visit 1) and with (Visit 2) initial instillation of artificial tears. Symptoms were assessed using the Ocular Surface Disease Index (OSDI), Symptom Assessment in Dry Eye questionnaire version two (SANDE II) and Computer Vision Syndrome Questionnaire (CVS-Q). The ocular surface was assessed by measuring corneal higher order aberrations, tear meniscus height (TMH), conjunctival redness, blink rate and incomplete blinking, lipid layer thickness (LLT) and non-invasive keratograph break-up time (NIKBUT). SANDE II scores were >0 after the computer task in both groups (p ≤ 0.01). SANDE II and CVS-Q scores did not differ between LASIK and controls (p ≥ 0.43). Greater bulbar-temporal conjunctival redness, TMH and LLT and shorter NIKBUT were found after computer use in the LASIK group (p ≤ 0.04), whereas no changes were observed in the controls (p ≥ 0.20). Lower SANDE II and CVS-Q scores were reported at Visit 2 compared with Visit 1 in both groups (p ≤ 0.01). Likewise, no worsening of dry eye signs was observed at Visit 2 (p ≥ 0.11). Ocular symptoms reported during computer use were comparable between the groups. However, a worsening of dry eye signs was mostly observed in post-LASIK individuals. The instillation of artificial tears was effective in preventing the effects of computer use on the ocular surface in post-LASIK patients.

Artificial Tear Instillation-Induced Changes in Corneal Topography.

This study aims to compare changes of corneal topography (Galilei G4) before and after the instillation of artificial tears in patients with dry eye disease (DED). Corneal topography was performed in patients 1 min before and after artificial tear instillation. Two types of artificial tears were used: 1% polysorbate 80 (PSB) and 0.5% carboxymethylcellulose (CMC). Of 135 patients, PSB and CMC were instilled in 101 and 34 eyes, respectively. The average value of Sim K increased significantly after instillation (44.07 ± 2.26 diopter (D)) compared to before (43.90 ± 2.02 D, p = 0.006) the instillation of artificial tears. Mean Sim K astigmatism was statistically increased after PSB instillation (1.48 ± 2.17 D) compared to before instillation (1.31 ± 2.10 D, p = 0.049). An axis change of astigmatism 10° or more after artificial tear instillation was found in 51.9% of patients, and 30° or more in 20.0% of patients. Increased Sim K value and significant changes in the astigmatic axis in the corneal topography were observed after instillation of artificial tears in DED patients. PSB instillation had a greater effect on corneal keratometry values than CMC instillation.

Immediate effects of artificial tears with and without preservatives containing hyaluronic acid and carboxymethyl cellulose

Background: Currently, hyaluronic acid (HA) and carboxymethyl cellulose sodium (CMC) are common polymers incorporated in artificial tears (ATs). The aim of the present study was to evaluate the immediate effect of preservative- and preservative-free HA- and CMC-containing ATs on tear-film parameters and determine patient preference after AT instillation.&#x0D; Methods: In this prospective, double-blind, randomized, comparative study, we assessed fluorescein tear break-up time (TBUT), bulbar redness, and tear ferning pattern (TFP) up to 60 min after the instillation of ATs with and without preservatives containing HA and CMC in the recruited participants. To test patient preference, each patient was administered with the Ora Calibra™ Ocular Discomfort and 4-Symptom Questionnaire (OOD4SQ; scale of 0–5) before and 60 min after the instillation of ATs. The selection of 14 descriptive words based the 11-point Ora Calibra™ Drop Comfort Scale (ODCS; scale of 0–10) was administered immediately after instillation of each AT to test the drop comfort score.&#x0D; Results: We enrolled 200 eyes of 200 patients, including 163 (81.5%) women and 37 (18.5%) men, with a mean (standard deviation) age of 28.38 (5.42) years. Immediately or 5, 15, or 60 min after the instillation, the mean TBUT did not differ by presence of preservatives, HA, or CMC (all P &gt; 0.05). However, it was significantly higher 5-min post-instillation compared to baseline and significantly lower 15- and 60-min post-instillation (all P &lt; 0.05). The mean grade of bulbar redness immediately or 3, 5, 15, or 60 min after instillation did not differ by presence of preservatives for HA or CMC containing ATs (all P &lt; 0.05). It did not differ significantly 3-, 5-, 15-, or 60-min post-instillation compared to baseline (all P &gt; 0.05). The mean drop comfort scale after the instillation of ATs did not differ significantly by presence of preservatives, HA, or CMC (all P &lt; 0.05). Positive descriptive words were selected by a higher proportion of participants in both groups. According to OOD4SQ, the overall discomfort and mean dryness scores improved significantly after instillation of HA-containing ATs (both P &lt; 0.05), while the mean burning sensation, grittiness, and stinging scores remained unchanged (all P &gt; 0.05). The overall discomfort and mean scores for each ocular symptom (P &lt; 0.05), except for stinting (P &gt; 0.05), improved significantly after instillation of CMC-containing ATs. The TFP did not change significantly from baseline to 60 min after the instillation of any AT (P &gt; 0.05).&#x0D; Conclusions: Both ATs with and without preservatives containing HA and CMC produced positive short-term objective and subjective effects. However, TBUT, TFP, bulbar redness, and patient feedback were comparable for both HA- and CMC-containing ATs. Further trials with longer observation periods or the recruitment of patients with different severities of dry eye could provide more robust and clinically applicable conclusions.

Influence of specialized medical devices intended for microsurgeries on the dynamic characteristics of the IOP-level, refraction and the ocular surface of ophthalmic surgeons

Most ophthalmic interventions are examples of microinvasive surgery using microscopes of various modifications, which can have a negative impact on the eye condition of ophthalmic surgeons. Thus, presumably, a prolonged and repeated change in the accommodation of surgeons can contribute to a change in the dynamic refraction of the eye; separate articles began to appear describing the development of artifical dry eye syndrome (DES). It seems obvious that systematic work in the operating room and the conduct of microsurgical operations affect the organ of vision of ophthalmic surgeons.Purpose: to determine the degree of influence of equipment intended for microsurgical ophthalmic operations on the dynamic characteristics of the level of intraocular pressure, refraction and the state of the eye surface of ophthalmic surgeons.Materials and Methods. As part of a multicenter analytical scientific cross‑sectional study, data from 48 people (48 eyes, men – 50% and women – 50%) were analyzed. The indicators of total tear production (Schirmer test, I), as well as individual tonometry and refractive index characteristics of volunteers at the beginning and at the end of the surgical day, were studied. Individual risk factors for the development and progression of the dry eye syndrome (age, smoking, use of hormonal systemic drugs, wearing soft contact lenses), as well as instillation of artificial tears, were recorded. Additionally, all subjects completed the Ocular Surface Disease Index (OSDI) questionnaire.Results. After the operation day, which averaged 2.8 ± 0.2 hours, the subjects (mean age – 41.9 ± 1.1 years) had a statistically significant change in the index of tear production (from 11.9 ± 0.9 to 10.8 ± 1.7 mm, p = 0.01; Z = 2.407). A significant decrease in the parameters of the Schirmer test 1 was found in the age group of surgeons under 40 years old (p = 0.018; Z = 2.353), and in persons over 40 years old, there was a tendency for a decrease in tear production parameters, which was not statistically significant (p = 0.213; Z = 1.244). There was a tendency to increase the IOP‑level in surgeons of both age groups (p = 0.314; Z = 1.006 and p = 0.632; Z = 0.407, respectively). In addition, in surgeons older than 40 years, there was a change in accommodation, expressed in an increase in myopic refraction by 0.5 diopters at the end of the surgical day (p = 0.076; Z = 1.771).Conclusions. The use of specialized professional equipment (operating microscope) was found to have a negative effect on total tear production regardless of the presence of traditional risk factors for DES. The severity of violations depended on the age category of the subjects. The data obtained are of particular relevance in the period of development and progression of methods of surgical treatment of ophthalmic diseases and substantiate the need to develop specific preventive measures.

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

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. 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. 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). 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.

Digital display use and contact lens wear: Effects on dry eye signs and symptoms.

To assess the potential additive effects of short-term display use and contact lens (CL) wear on the ocular surface and tear film. Thirty-four healthy volunteers (20.87±2.33years old) participated in this study. Participants' dry eye symptoms, ocular surface, tear film and pupil size were assessed before and after executing a 20-min reading task on a computer and a smartphone with and without CL wear, or with CL wear and artificial tear instillation. 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 (BR) and pupil size. Higher symptoms were reported after reading on both displays with and without CLs (p≤0.001) for short periods. BR was higher and NIKBUT shorter after reading on the computer regardless of wearing CLs (p≤0.02 and p≤0.02, respectively), while TMH increased for all conditions (p≤0.02) except for CL computer reading (p=0.23). Reading with CLs did not lead to greater signs of dry eye (BR, NIKBUT) and symptoms compared with reading unaided (p>0.05), although a smaller increase in TMH was observed when reading on the computer with CLs (p=0.005). Artificial tear instillation during CL wear led to a smaller increase in symptoms (p≤0.02), a smaller increase in BR (p≤0.04) and a decrease in NIKBUT (p=0.02) compared to reading without correction. Disposable CL wear had no additive effects on signs and symptoms of dry eye when using digital devices for short periods. The instillation of artificial tears is an effective strategy for reducing the impact of display use in CL wearers.

Efficacy of Artificial Tears Based on an Extract of Artemia salina Containing Dinucleotides in a Rabbit Dry Eye Model.

(1) Background: Artemia salina is a brine shrimp containing high concentrations of dinucleotides, molecules with properties for dry eye treatment. For this reason, the purpose of the study was to evaluate the effect of the artificial tears based on an extract of Artemia salina in a rabbit dry eye model. (2) Methods: A prospective and randomized study was carried out. Twenty rabbits were divided into 4 groups (n = 5, each group): healthy rabbits, dry eye rabbits, dry eye rabbits treated with hypromellose (HPMC), and dry eye rabbits treated with Artemia salina. Dry eye was induced by the topical instillation of 0.2% benzalkonium chloride. The measurements were performed before and after the treatment for 5 consecutive days. (3) Results: The topical instillation of artificial tears containing Artemia salina showed beneficial effects on tear secretion, tear break-up time, corneal staining, the density of Goblet cells, heigh of mucin cloud secreted by these cells, and mRNA levels of IL-1β and MMP9 in conjunctival cells. Compared with the HPMC, there was a statistically significant improvement (p < 0.05) with the Artemia salina in all the variables under study, except for the conjunctival hyperemia, density of Goblet cells, and mRNA levels of IL-6. (4) Conclusions: The potential of artificial tears based on Artemia salina as a secretagogue agent for dry eye treatment was confirmed, opening the door for future clinical trials and studies to extrapolate the findings for dry eye patients.

How Do Different Digital Displays Affect the Ocular Surface?

Digital display use has been accepted as a contributing factor to dry eye disease. Nowadays, plenty of new models of digital displays have been developed, and the differences in their nature and the ways in which they are set and used may contribute to differences in the eye-related problems they cause. This study aimed to analyze the differences in ocular surface, tear film, and visual fatigue parameters after reading on different digital displays, with and without initial instillation of artificial tears. Thirty-one healthy individuals ranging in age from 20 to 26 years (mean ± standard deviation, 21.26 ± 1.73 years) were included in this prospective clinical study. Subjects' ocular surface, tear film, and visual fatigue parameters were assessed after reading for 15 minutes on a laptop computer, tablet, e-reader, and smartphone with matching characteristics and a baseline measurement. Measurements were taken with and without the instillation of artificial tears before the reading tasks and included the Ocular Surface Disease Index questionnaire, the Computer Vision Syndrome Questionnaire, tear meniscus height, the Schirmer I test, noninvasive keratograph break-up time, osmolarity, bulbar redness, and pupil size. Statistically significant differences in the Ocular Surface Disease Index, Computer Vision the Syndrome Questionnaire, tear meniscus height, the Schirmer I test, noninvasive keratograph break-up time, osmolarity, and bulbar redness were obtained when comparing the displays (P < .05). Best results were obtained with the smartphone and the e-reader. Conversely, the computer produced the highest disturbance on the ocular surface and tear film. Finally, the instillation of artificial tears revealed no statistical improvement of ocular surface or tear film parameters for the same device (P > .05). Taking into account the clinical tests for dry eye diagnosis, the smartphone may be considered as the least disturbing display, producing lower dry eye signs and symptoms in comparison with other devices.

Dry Eye: The Effect of Chi-Ju-Di-Huang-Wan Plus Si Wu Tang and the Underlying Mechanism.

Objectives: In this pilot study, the effect of 970 mg Chi-Ju-Di-Huang-Wan (CJDHW) plus 30 mg four-substance decoction (Si Wu Tang; CJDHWSWT) was evaluated, in terms of its ability to alleviate dry eye symptoms and its therapeutic mechanism. Methods: This double-masked prospective investigation has recruited dry eye patients who have been randomly selected into two groups, namely treatment (n = 15) versus nontreatment (n = 15). In the treatment group, a daily oral intake of CJDHWSWT plus eye drops systane ultra was given for 90 consecutive days. In the nontreatment group, only defined eye drops were prescribed. The examinations included Schirmer's test, fluorescein-stained superficial punctate keratitis (SPK), artificial tear consumption, tear vascular endothelium growth factor (VEGF) level, and ocular surface disease index. The drug safety tests included liver and kidney functions, and complete blood counts. The candidates were observed during the screening visit and the following three monthly follow-ups. The data were analyzed by unpaired Student's t-test. Results: Compared to no significance in the nontreatment group, CJDHWSWT significantly (p = 0.03) increased the tear secretion after 3 months of intake. Furthermore, in contrast to no significance in the treatment group, there were significant alterations, including (i) increased fluorescein-stained SPK areas (p = 0.03); (ii) increased artificial tear instillation amount (p = 0.03); (iii) elevated tear VEGF protein levels (p = 0.03) in the nontreatment group; and (iv) significant improvement in clinically relevant phenomenon (e.g., reading limit and uncomfortable feeling in windy conditions), after treatment of artificial tear plus oral intake of CJDHWSWT. As shown by the post-treatment normal defined laboratory data, there were no adverse drug effects. Conclusions: This study has supported that CJDHWSWT is safe and effective in relieving dry eye's clinically relevant symptoms/phenomena. CJDHWSWT avoided the tear VEGF upregulation probably induced by dry eye-associated hypoxia/ischemia.

Anterior Segment Biometry with Phenylephrine and Tropicamide during Accommodation Imaged with Ultralong Scan Depth Optical Coherence Tomography.

Purpose To investigate the influence of phenylephrine and tropicamide on anterior segment biometry with ultralong scan depth optical coherence tomography (UL-OCT) during accommodation. Methods In this study, 20 left eyes of healthy volunteers with a mean ± standard deviation age of 31.05 ± 5.84 years and a mean refraction of −1.16 ± 1.11 diopters (range 0∼−3.0 D) were imaged using UL-OCT after instillation of artificial tears, phenylephrine, and tropicamide in three follow-up trials, respectively. At each follow-up trial, two repeated measurements were performed at states of relax and 5D accommodative stimulation. The dimensional parameters included central corneal thickness (CCT), anterior chamber depth (ACD), pupil diameter (PD), lens thickness (LT), and horizontal radii of the lens anterior and posterior surface curvatures (LAC and LPC). Results Tropicamide led to larger pupil, deeper ACD, thinner LT, and flatter crystalline lens surface (P < 0.05). Phenylephrine induced an increase in PD (P < 0.05), while no significant changes were seen in ACD, LT, LAC, and LPC (P > 0.05). CCT did not change after both phenylephrine and tropicamide instillation in this study (P > 0.05). Tropicamide induced the loss of accommodation and phenylephrine achieved pupil dilation without affecting the accommodation. PD, ACD decreased, LT increased significantly and the anterior and posterior surface of the lens in a 6.294 mm of diameter optical zone became steeper during accommodation after administration of phenylephrine (P < 0.05). Conclusion The anterior segment physiology changed after tropicamide instillation. Besides, tropicamide induced the loss of accommodation and phenylephrine preserved the accommodation with a larger pupil. And, the anterior and posterior surface of lens in a 6.294 mm of diameter optical zone became steeper during the accommodation.

An imaging system integrating optical coherence tomography and interferometry for in vivo measurement of the thickness and dynamics of the tear film

BackgroundThe outermost layer of the tear film consists of a thin lipid layer (LL). The lipid layer serves as a barrier against evaporation of the aqueous component of the tear film. The ability to simultaneously image both the lipid layer thickness and overall tear film thickness is novel, and will help further understandings of mechanisms of how the lipid layer assembles and interacts with the full tear film thickness.MethodsWe developed a system that combines simultaneous optical coherence tomography (OCT) and thickness dependent fringes (TDF) interferometry for in vivo imaging of the tear film. The OCT possesses an axial resolution of 1.38 µm in tear film, providing an accurate measurement of the thickness of the overall tear film. The TDF can detect a minimal change of approximately 15 nm in LL thickness. In addition, the spatial resolution of TDF images in x–y plane is 5 µm.ResultsThe effect of instilling artificial tears on the PCTF and PLTF was examined. In both contact lens and non-contact lens wear, it could be observed from the OCT results that instillation of artificial tears increased the thickness of the overall tear film immediately, followed by a gradual reduction thereafter. These findings were consistent with other studies. However, unlike those previous reports, the thickness of the LL in this study was quantified simultaneously with the TDF subsystem. The results showed that bulking agents such as these artificial tears were not necessarily intended to increase the LL thickness. Immediately after instillation of artificial tears, the PCTF increased from 4.4 ± 0.97 to 20.3 ± 3.6 µm. The PCTF then decreased to 8.8 ± 2.1 µm at 4 min post-instillation. The thicknesses of the LL were 62.4 ± 14.5 nm, 48.7 ± 5.3 nm, and 55.2 ± 9.8 nm at pre-drop instillation, post-drop instillation, and 4-min post-drop instillation, respectively.ConclusionsIn this work, we have described a novel imaging system that integrated OCT and TDF imaging techniques, which may facilitate the study of many physiological and clinical aspects of the tear film.

Effects of Menthol-Containing Artificial Tears on Tear Stimulation and Ocular Surface Integrity in Normal and Dry Eye Rat Models

ABSTRACTPurpose: To evaluate the effects of menthol-containing artificial tears on tear stimulation and ocular surface integrity in normal and dry eye rat models.Methods: A total of 54 male Lewis rats were used. The levels of tear secretion and tear MUC5AC concentrations were compared between the menthol-containing artificial tear-treated group (menthol group) and the vehicle-treated group (vehicle group). The groups were compared after a single instillation to evaluate the immediate effects, and after repeated instillation (five times a day for 5 days) to evaluate the longer-term effects. Tear lactate dehydrogenase (LDH) activity was measured to evaluate eye drop instillation-induced ocular surface damage. The effects of menthol-containing artificial tears were also evaluated in a dry eye rat model.Results: After a single instillation of menthol-containing artificial tears, tear secretion increased from 4.37 (±0.75) mm at baseline to 7.37 (±1.60) mm. However, after repeated instillations, the effects of tear stimulation decreased. The tear MUC5AC concentration was significantly lower in the menthol group than in the vehicle group after a single instillation, but not after repeated instillation. However, the tear LDH concentration was significantly increased in the menthol group after repeated instillation. In the dry eye rat model, the extent of menthol-induced tear stimulation was reduced.Conclusions: Menthol-containing artificial tears increased tear secretion, but lowered the tear MUC5AC concentration. Menthol-induced tear stimulation was reduced after repeated instillation for 5 days and in the dry eye rat model. Conversely, repeated instillation of menthol-induced ocular surface damage, resulting in increased tear LDH activity.

Eyesight quality and Computer Vision Syndrome.

The aim of the study was to analyze the effects that gadgets have on eyesight quality. A prospective observational study was conducted from January to July 2016, on 60 people who were divided into two groups: Group 1 - 30 middle school pupils with a mean age of 11.9 ± 1.86 and Group 2 - 30 patients evaluated in the Ophthalmology Clinic, "Sf. Spiridon" Hospital, Iași, with a mean age of 21.36 ± 7.16 years. The clinical parameters observed were the following: visual acuity (VA), objective refraction, binocular vision (BV), fusional amplitude (FA), Schirmer's test. A questionnaire was also distributed, which contained 8 questions that highlighted the gadget's impact on the eyesight. The use of different gadgets, such as computer, laptops, mobile phones or other displays become part of our everyday life and people experience a variety of ocular symptoms or vision problems related to these. Computer Vision Syndrome (CVS) represents a group of visual and extraocular symptoms associated with sustained use of visual display terminals. Headache, blurred vision, and ocular congestion are the most frequent manifestations determined by the long time use of gadgets. Mobile phones and laptops are the most frequently used gadgets. People who use gadgets for a long time have a sustained effort for accommodation. A small amount of refractive errors (especially myopic shift) was objectively recorded by various studies on near work. Dry eye syndrome could also be identified, and an improvement of visual comfort could be observed after the instillation of artificial tears drops. Computer Vision Syndrome is still under-diagnosed, and people should be made aware of the bad effects the prolonged use of gadgets has on eyesight.

Alleviating effects of artificial tear instillation on S-1-induced ocular toxicity in dogs.

S-1 is an anticancer agent that consists of tegafur, gimeracil, and oteracil potassium at a molar ratio of 1:0.4:1. S-1 is used to treat metastatic and resectable gastric cancer. However, the extensive use of S-1 in clinical practice results in watery eyes, a serious clinical problem, which worsens patients' quality of life. Although repeated instillation of artificial tears is recommended, therapy or prophylaxis against S-1-induced ocular toxicity has not been established. In the present study, we evaluated the alleviating effects of repeated artificial tear instillation on S-1-induced ocular toxicity in dogs. Ten beagle dogs (5 males and 5 females) were orally administered 3 mg/kg/day of S-1 for up to 21 days. Five drops of artificial tears were instilled to the left eye, eight times daily, within 6 hr after S-1 administration. The mean cornea staining score tended to be low in the left eye with repeated artificial tear instillation. In 4 out of 10 dogs, the corneal staining score of the left eye was more than 2-fold lower than that of the right eye. The incidence of dogs indicating normal tear drainage increased and stenosed tear drainage decreased by repeated artificial tear instillation. In conclusion, we demonstrated that artificial tear instillation can alleviate corneal surface damage induced by S-1 in dogs.

Tear Film Thickness After Treatment With Artificial Tears in Patients With Moderate Dry Eye Disease

This study was designed to investigate the effect of a single-drop instillation of different lacrimal substitutes on tear film thickness (TFT) assessed with optical coherence tomography in patients with mild to moderate dry eye disease. The study was performed in a randomized, double-masked, controlled parallel group design. Patients received a single dose of either unpreserved trehalose 30 mg/mL and sodium hyaluronate 1.5 mg/mL (TH-SH, Thealoz Duo), unpreserved sodium hyaluronate, 0.15% (HA, Hyabak) or sodium chloride, 0.9% (NaCl, Hydrabak) eye drops. Sixty patients finished the study according to the protocol. TFT was measured with a custom-built ultrahigh-resolution Fourier domain optical coherence tomography system providing a resolution of 1.2 μm. The mean TFT before treatment was 2.5 ± 0.4 μm. Ten minutes after instillation, TFT significantly increased in the TH-SH group from 2.4 ± 0.4 to 3.1 ± 0.9 μm (P < 0.01) and in the HA group from 2.4 ± 0.3 to 2.9 ± 0.5 μm (P < 0.01), whereas no significant change was observed in the NaCl group (from 2.6 ± 0.4 to 2.7 ± 0.4 μm, P = 0.76). The increase in TFT remained statistically significant up to 240 minutes after administration of TH-SH. In contrast, the increase in TFT after administration of HA was only statistically significant at 10, 20, and 40 minutes after drop instillation. The findings of this study indicate that single instillation of TH-SH and HA eye drops increases TFT in patients with dry eye disease. The data also indicate longer corneal residence of the TH-containing eye drops. The effect of multiple instillation and long-term use of artificial tears on TFT warrants further investigation.

Time course of changes in tear meniscus radius after instillation of artificial tears

Time course of changes in tear meniscus radius after instillation of artificial tears

Time course of changes in tear meniscus radius and blink rate after instillation of artificial tears.

Using a novel digital meniscometer (PDM), alterations in tear meniscus radius (TMR) were measured simultaneously with blink rate (BR) following the instillation of artificial tears. Central TMR and BR of 22 subjects (11 male and 11 female; mean age, 24.3 ± 2.6 SD years) were measured at baseline, and 0, 1, 5, 10, and 30 minutes after instillation of an artificial tear containing hydroxypropyl-guar and glycol (SYS) or saline (SAL). A dose of 35 μL was applied in one eye in a randomized order with a washout period between each drop. For SAL, compared to baseline TMR (0.33 ± 0.08 mm), TMR significantly increased with drop instillation (1.55 ± 0.69 mm) and at 1 minute (0.66 ± 0.36 mm; P < 0.05), but returned to baseline after 5 minutes. For SYS, TMR (0.32 ± 0.07 mm) remained significantly increased after application (1.62 ± 0.81 mm), and at 1 minute (0.81 ± 0.43 mm) and 5 minutes (0.39 ± 0.08 mm; P < 0.05). Compared to baseline BR with SAL (14.8 ± 7.7) and SYS (14.9 ± 9.4), values were significantly increased upon drop instillation (22.5 ± 11.8; 21.3 ± 11.8; P < 0.05), but returned to baseline after 1 minute. Dry eye symptoms were correlated with baseline BR (r = 0.550, P = 0.008). Results indicate that PDM can detect changes in TMR following instillation of artificial tears. Difference in residence time reflects the different viscosity of each drop. An overload with a large drop may result in an initially increased BR.

A Study of the Short-Term Effect of Artificial Tears on Contrast Sensitivity in Patients With Sjögren's Syndrome

Primary Sjögren's syndrome often includes dry eye manifestations, including a reduction in optical quality from the compromised ocular surface. This study was designed to measure the effect of different artificial tears on the contrast sensitivity of Sjögren's syndrome patients from 5 minutes to 4 hours after instillation. Ten normal subjects and 10 subjects with ocular manifestations of Sjögren's syndrome were compared at baseline, including staining scores, a dry eye questionnaire, and contrast sensitivity testing. Changes in contrast sensitivity in the Sjögren's syndrome group were measured over a 4-hour period after instillation of a variety of artificial tears. Statistically significant differences in staining, subjective questionnaire scores, and contrast sensitivity were measured between the normal and Sjögren's syndrome groups. Statistically significant changes in contrast sensitivity were measured over time after artificial tear instillation, with the greatest effect at 3 to 6 cycles/deg. The more mucoadhesive artificial tears demonstrated a significantly greater effect. The effects of artificial tears on measured contrast sensitivity in dry eye patients in the postinstillation period of 5 minutes to 4 hours appear limited, but an artificial tear with more mucoadhesive properties showed more benefit than those that do not. Modest effects on contrast sensitivity, primarily at medium spatial frequencies, were observed with the more mucoadhesive formulations.