Tear ascorbic acid levels and the total antioxidant status in contact lens wearers: A pilot study (original) (raw)
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Tear changes in contact lens wearers following overnight eye closure
Current Eye Research, 1998
Purpose. Tear protein composition alters during eye closure, by becoming rich in secretory IgA (sIgA) and certain complement proteins. This may reflect altered ocular defense mechanisms during eye closure. Since overnight wear of contact lenses (CLs) is associated with an increased risk of corneal infection and inflammation, this study aimed to quantify tear protein changes with overnight soft CL wear.
Experimental and therapeutic medicine, 2018
Prolonged and continuous use of contact lenses for as long as 3 or 4 weeks is common in Mexico due to the low socioeconomic status, poor patient education and self-neglect. Furthermore, wearing contact lenses with low oxygen permeability is common due to their low cost. Thus, patients seek ophthalmologic evaluation due to signs and symptoms of overuse such as red eye, discomfort and tearing. In the present study, the effect of wearing soft contact lenses with a low oxygen permeability on the tear fluid composition after 1 day, 1 week and 1 month without removing them was examined. In this prospective clinical trial, several tear fluid biomarkers were measured in 84 non-adapted contact lens wearers (NACLWs), including the pH, electrolytes, osmolarity, pro-inflammatory molecules [interleukin (IL)-8, IL-1β and interferon (IFN)-γ], total protein (TP) levels and enzymes [aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and alkaline phosphatase...
Tear Stability, Corneal Staining and Dry Eye Symptoms in Contact Lens Wearers
Jurnal Sains Kesihatan Malaysia
The aim of this study was to examine tear stability of contact lens wearers (CLW) in young Malay adults aged 18 and above and to compare the results with non-contact lens wearers (NCLW). Corneal staining and McMonnies Dry Eye Questionnaires (MDEQ) scores between habitual soft CLW and NCLW were also compared. It also aimed to find correlation between tear stability and MDEQ scores. Quasi-experimental and case control study was conducted among 53 participants (53 right eyes) at UiTM Vision Care, UiTM Puncak Alam Campus. Twenty six participants were habitual soft CLW and twenty seven were NCLW. Tear stability was measured using non-invasive tear break-up time (NIBUT) and invasive tear break-up time (TBUT). Corneal staining was measured using Efron Grading Scale and dry eye symptoms evaluated using MDEQ. Mean scores of NIBUT and TBUT for CLW were 5.23 ± 7.3 sec and 2.19 ± 2.41 sec respectively; for NCLW were 8.71 ± 4.33 sec and 3.00 ± 1.69 sec respectively. There were significant differences in NIBUT (Mann-Whitney U, p = 0.0001) and TBUT (Mann-Whitney U, p = 0.001) between the CLW and NCLW. There was also significant difference in percentage of corneal staining found between the CLW (22.6%) and NCLW (7.5%), (Chi-square, p = 0.013). However no significant difference was found in MDEQ scores between the CLW (7.54 ± 3.62) and the NCLW (8.15 ± 3.38) group, (Mann-Whitney U, p = 0.42). There were also no correlations found between tear stability and MDEQ scores in the two groups. The results of this study showed NIBUT and TBUT values were significantly higher in NCLW than in CLW and corneal staining was more extensive in CLW. Contact lens practitioners need to be aware of changes in tear stability as results of contact lens wear and take the necessary action to improve on the management of their patients during aftercare consultation.
Cornea, 2016
Purpose: To analyze the influence of environmental conditions on the concentrations of tear inflammatory mediators during contact lens (CL) wear. Methods: Fifty-four CL wearers completed 4 visits combining the bilateral use of omafilcon A or comfilcon A CL and a 90-minute exposure to 2 environmental conditions: standard [50% relative humidity (RH), 23°C, 930 mb] or adverse (5% RH, localized air flow, 23°C, 750 mb). Four microliters of tears was collected by capillarity from each subject. Changes in concentration of epidermal growth factor (EGF); interleukin (IL)-1 receptor antagonist, IL-1b, IL-2, IL-4, IL-6, and IL-8; tumor necrosis factor (TNF) a; monocyte chemoattractant protein-1; and matrix metalloproteinase (MMP)-9 were analyzed. The effects of the environment, CL type, and symptoms were evaluated using a 3-way mixed analysis of variance with repeated measures. Results: Under the standard condition, EGF significantly increased [0.36; 95% confidence interval (CI), 0.08 to 0.64], and IL-1b (20.48; 95% CI, 20.84 to 20.12) and IL-2 (20.48; 95% CI, 20.87 to 20.09) significantly decreased. Under the adverse condition, IL-6 significantly increased (0.35; 95% CI, 0.09 to 0.62). Comparing conditions, EGF change was significantly lower (P = 0.02) and IL-1b, IL-2, IL-6, and TNF-a changes were significantly higher (P # 0.04) under the adverse condition. Additionally, IL-1b significantly decreased with comfilcon A (20.51; 95% CI, 20.88 to 20.15), being significantly lower (P = 0.01) than the change with omafilcon A (0.06; 95% CI, 20.23 to 0.35). Conclusions: The secretion of several tear inflammatory mediators during CL wear differs depending on the environmental conditions and the CL type used. These outcomes might help to understand the effect of the environment and CL materials on the ocular surface of CL wearers.
Medical Journal of Indonesia, 2020
BACKGROUND Soft contact lens (SCL) wear can lead to a corneal hypoxia. However, there is a lack of studies looking for corneal hypoxia biomarkers in tear. This study aimed to investigate corneal hypoxia among SCL wearers based on hypoxia-inducible factor-1α (HIF-1α) expression, tear lactate dehydrogenase (LDH), and malate dehydrogenase (MDH) activities. METHODS A nonrandomized clinical trial was conducted on two groups. SCLs were prescribed for 2 months to a group of new wearers. Meanwhile, SCL wear was discontinued for 1 month in a group of long-term wearers. Tear samples were then collected on days 1, 7, 14, 28, and 56 after treatment. Repeated-measures analysis of variance and Friedman’s test with post-hoc statistical analysis were used to evaluate biomolecular changes (HIF-1α concentration, LDH, and MDH activities) in both groups. RESULTS A total of 14 subjects (28 eyes) were enrolled in each group. In new wearers, there was a significant decrease in MDH level (p = 0.010) and no...
Tear Film Evaluation in Contact Lens Wearers and Non Wearers
Background: Dry eye symptoms are more frequent in contact lens wearers than in non wearers. Dry eye is considered relatively common in contact lens wearers than non-wearers. However, there was no any report in our clinical setting that compared and addressed the issue related to dry eye and its symptom in contact lens wearers. The present study was conducted to compare pre-ocular tear film in contact lens wearers (CLW) and contact lens non wearers (CLNW), and evaluate the relationship between clinical and subjective assessment of dry eye symptoms.
Tear buffering in contact lens wearers
Acta Ophthalmologica, 2009
The buffering capacity of tears collected from contact lens wearers was compared to that from non-contact lens wearers. Three groups of subjects were investigated: 6 subjects not wearing contact lenses, 3 subjects wearing rigid contact lenses, and 3 subjects wearing hydrogel contact lenses. Each of the 12 subjects provided, on 6 separate occasions, 100 pl of tears. The pH of the tears was measured with a closed chamber, temperature stabilized micro-electrode system firstly on collection and then after titration with acid and base. In all, 28 titration steps across the acid-base spectrum were completed for each subject's tears on each occasion. These tear pH responses to acid-base challenge were compared to that of unbuffered distilled water for the same titration procedure. There was no statistically significant effect of contact lens wear on tear buffering capacity, but considerable inter-subject variability was noted.
Contact Lens and Anterior Eye, 2011
To prospectively investigate the effects of 2 week senofilcon A contact lens (CL) daily wear on the functional visual acuity (VA), ocular surface and tear film. Methods: Seventeen right eyes of 17 senofilcon A CL wearers without any ocular or systemic diseases were examined before and 2 weeks after lens wear. Visual acuity measurements, tear evaporation rate, ELISA for tear cytokines, strip meniscometry, tear lipid layer interferometry, tear film break-up time (BUT), in vivo confocal microscopy, corneal sensitivity, ocular surface vital staining, Schirmer I test and brush cytology for MUC5AC mRNA expression were performed before and after CL wear. Results: The best corrected Landolt VA, functional VA parameters, the mean lipid layer interferometry grades, tear evaporation rates, Schirmer test values, vital staining scores and in vivo confocal microscopy parameters did not show any significant differences after 2 weeks of CL wear. The tear film BUT showed a significant decrease together with a significant down regulation of MUC5 AC mRNA expression after CL wear. A statistically significant elevation in the mean tear interleukin (IL)-6 concentration was also observed after 2 weeks of CL wear. Conclusions: Two week senofilcon A daily CL wear seems to be associated with tear instability, a decrease in MUC5AC expression, and elevation of IL-6 in tears without significant alterations in epithelial damage scores or in the morphology or density of in vivo keratoconjunctival cells and nerves. Alterations associated with long term wear and patients with dry eye disease need to be studied in future trials.
Clinical Optometry
Purpose: To compare the effects of artificial tears (ATs) in wearers of biweekly replacement silicone hydrogel contact lenses (BW-Ws) and wearers of daily disposable contact lenses (DD-Ws) of the same material. Materials and Methods: The aqueous-supplementing ATs, OPTOyalA and OPTOidro, were assigned to be used for 2 weeks to healthy and young subjects: 1) 20 (8 and 12, respectively) BW-Ws wearing silicone hydrogel somofilcon A CLs (Clariti Elite), 2) 18 (9 and 9, respectively) DD-Ws wearing silicone hydrogel somofilcon A CLs (Clarity 1 Day), and 3) a control group of 33 (16 and 17, respectively) N-Ws. Ocular symptoms and comfort, tear volume and stability, and ocular surface condition were assessed by Ocular Surface Disease Index (OSDI), 5-Item Dry Eye Questionnaire (DEQ5), tear meniscus height (TMH), non-invasive tear break-up time (NIBUT), and evaluation of ocular redness (OR). The assessment was performed before and after 15 days of use of the ATs in the 3 groups (BW-Ws, DD-Ws, and N-Ws). Results: No clear significant difference was noted in symptoms and signs between OPTOyalA and OPTOidro irrespectively of the group of people studied. ATs use for 15 days produced a significant improvement in DEQ5 and OR in DD-Ws (Δ=−34%, p=0.006; Δ=−23%, p<0.001) and in N-Ws (Δ=−21%, p=0.001; Δ=−10%, p=0.006) but not in BW-Ws (Δ=−5%, p=0.072; Δ=−2%, p=0.257). No significant change was noted for TMH. Conclusion: In young and healthy subjects, the aqueous-supplementing effect of the ATs under consideration is more a rinsing and tear replacem ent effect than an increase in tear volume, and it produces an improvement of the eye redness and ocular symptoms. Contact lens wear influenced the effectiveness of ATs in a way which is correlated with the CL replacement schedule.
Tear film evaluation and management in soft contact lens wear: a systematic approach
Clinical and Experimental Optometry
The human tear film is a highly ordered structure consisting of a thin layer of lipid on the surface and a thicker aqueous-mucin phase, which increases in mucin concentration toward the corneal epithelial cell layer. The health of the tear film and ocular surface influences the likelihood of being able to achieve successful contact lens wear. Contact lens discomfort and dryness are the most frequent reasons why contact lens wearers experience reduced wearing times, which can eventually lead to contact lens discontinuation. Comprehensive clinical assessment of tear film integrity and ocular surface health is therefore essential prior to commencing contact lens wear, to enable the ocular surface environment to be optimised to support lens wear. These parameters should also be evaluated over the course of contact lens wear, in order to identify any aspects requiring clinical management and ensure maintenance of optimal lens-wearing conditions. This review summarises current knowledge relating to the effects of soft contact lens wear on the tear film and ocular surface. It also provides a systematic approach to evaluating tear film and ocular surface integrity, in order to guide the clinical management of tear film anomalies with respect to contact lens wear.