Pre-lens Tear Film Stability Research Articles

Daytime Changes in Tear Film Parameters and Visual Acuity with New-Generation Daily Disposable Silicone Hydrogel Contact Lenses-A Double-Masked Study in Symptomatic Subjects.

This prospective, double-masked, contralateral study aimed to analyze and compare daytime changes in pre-lens tear film (PLTF) stability and optical quality in symptomatic subjects wearing two contact lenses (CL). A secondary goal was to assess the performance of the PLTF by using dynamic topography techniques and analyzing surface asymmetry and irregularity indexes (SAI and SRI, respectively). Measurements were conducted on 20 symptomatic subjects (OSDI score > 13). Participants were fitted contralaterally and randomly with spherical Delefilcon A and Stenfilcon A CLs and underwent a series of measurements over 3 consecutive days: three in the morning (after 1-2 h of CL wear) and three in the afternoon (after 7-9 h of CL wear). High- and low-contrast visual acuity (HCVA and LCVA, respectively), pre-lens NIBUT, and dynamic topography were assessed. The contralateral fit of the two lenses allowed a direct and better comparison between them since they were exposed to the same conditions during the day. Consequently, both lenses demonstrated similar performance in HCVA, LCVA, and PLTF stability, with no statistically significant differences between them, although some fluctuations were observed throughout the day. Dynamic topography proved sensitive in evaluating temporal changes in the PLTF. The SRI index showed greater sensitivity to topographic changes due to lacrimal destabilization, making it potentially valuable for evaluating dry eye patients.

Comparison of the Pre-Lens Tear Film Stability and Visual Performance of a Novel and Two Other Daily Disposable Contact Lenses in Healthcare Professionals Wearing Facial Masks for Prolonged Time.

ObjectiveTo compare a novel daily disposable contact lens (DDCL) verofilcon A with other DDCL materials in terms of pre-lens tear film (PLTF) stabilization and visual performance for prolonged use in healthcare professionals with the use of masks.MethodsSubjects aged 20–40 years old were prospectively randomized into three study groups. Group 1: verofilcon A, group 2: nesofilcon A and group 3: senofilcon A. The subjects were evaluated at baseline with best corrected visual acuity (BCVA), non-invasive tear break up time (NIBUT) of pre-lens tear film, and high order aberrations (HoAs). After 28 days of CL use, NIBUT at 1, 4, 8, and 12 h, HoAs, contrast sensitivity (CS) with CVS100-E and contact lens dry eye questionnaire-8 (CLDEQ-8) were evaluated.ResultsBetween August and September 2021, 147 eyes of 77 subjects were included in the three study groups. At day 28, the CS scores at 18 cycles per degree, spatial frequencies, and the mean NIBUT scores at 4, 8, and 12 h were higher in the verofilcon A group compared to the nesofilcon A and at 12 h were higher compared to the senofilcon A (p < 0.05). The mean HoAs and CLDEQ-8 test scores were higher in the nesofilcon A group (p < 0.001).ConclusionThe results of this study suggest the superiority of the PLTF stabilization ability of verofilcon A in healthcare professionals with prolonged use of mask. The improved CS and NIBUT scores of this lens could be explained by a new and unique surface technology with greater than 80% water content.

Tear film stability over a myopia control contact lens compared to a monofocal design

ABSTRACT Clinical relevance: Tear film assessment is essential in contact lens wearers and it can improve the success rates of the fitting. Background: To compare the short-term effect of two contact lenses on pre-lens tear film stability and comfort: dual-focus contact lens (MiSight) and a monofocal contact lens (Proclear 1-day). Methods: This randomised, double-masked, crossover study was performed in twenty-eight healthy, myopic volunteers aged between 18 and 32 years (23.5 ± 4.1 years). Only one randomly chosen eye was assessed. Distance vision and refraction were evaluated at baseline. Each contact lens type (monofocal and dual-focus) was randomly fitted, always in both eyes. A visual analogue scale between 0 and 10 was used to assess general comfort, physical comfort, and visual comfort. Tear Film Surface Quality (TFSQ) index, TFSQ_area and auto Tear Break-Up Time were obtained using Medmont E-300 at baseline (naked eye condition) and 25 minutes after each contact lens insertion. Results: Refractive sphere and cylinder were, respectively, −1.36 ± 1.04 D (ranging from −6.00 to −0.25 D) and −0.23 ± 0.30 D (ranging from −0.75 to 0.00 D). TFSQ and TFSQ area were lower (meaning more stable tear film) at baseline when compared with both contact lens types (p < 0.025). Higher pre-lens tear instability (larger TFSQ and_TFSQ area values) was found with the dual-focus than the monofocal lens. Auto Tear Break-Up Time was higher at baseline than with each of the contact lenses, without statistically significant differences between both contact lens types. Visual analogue scales revealed statistically significant better scores in the monofocal contact lens than in dual-focus contact lens for general (0.77 ± 1.14 vs 3.12 ± 2.79), physical (0.96 ± 1.46 vs 2.19 ± 2.45) and visual comfort (1.27 ± 1.66 vs 3.92 ± 2.04). Conclusion: A slight reduction in short-term pre-lens tear film stability was found in the dual-focus design in comparison with the monofocal lens, potentially contributing to the deterioration of visual performance and comfort during dual-focus contact lens wear.

Comparison and Evaluation of Prelens Tear Film Stability by Different Noninvasive in vivo Methods.

PurposePrelens tear film stability of soft contact lens (SCL) play an important role for contact lens discomfort. In this study, we investigated the association between two types of noninvasive methods and evaluated the tear film stability with SCL using the methods.Patients and MethodsIn experiment 1, images of ring mire were recorded with a keratograph after focusing the pigment located at the front or back of the SCL. Interferometry and videokeratoscopy were used for the assessment of tear film stability in the right eye of 10 women, with two different cosmetic daily disposable SCLs: polymacon and etafilcon A with polyvinylpyrrolidone. Time to first distortion by noninvasive keratograph break up time (NIKBUT-first) was compared to noninvasive interferometry break up time (NIBUT). In experiment 2, ten normal females wore two different daily disposable SCLs: samfilcon A and narafilcon A. NIKBUT-first and NIBUT were compared between the lenses after 8 hours of SCL wearing.ResultsIn experiment 1, NIBUT-first without SCL was significantly correlated to NIBUT without SCL (r=0.445, P=0.0488, Pearson’s correlation coefficients). However, NIKBUT-first with SCL was not significantly correlated with NIBUT with SCL. In experiment 2, although NIKBUT-first was not significantly different between SCLs, samfilcon A had significantly longer NIBUT than narafilcon A (P=0.0315, paired t-test).ConclusionNIKBUT-first with SCL could be related to tear film stability between the lens and the corneal surface, but not to prelens tear film stability. NIIBUT could be a suitable method to evaluate prelens tear stability.

Objective Analysis of Pre-Lens Tear Film Stability of Daily Disposable Contact Lenses Using Ring Mire Projection.

PurposeThe primary objective of this study was to evaluate the in vivo pre-lens non-invasive drying-up time of two types of daily disposable contact lenses (DDCLs) after 12 hours of wear.MethodsThis prospective, randomized, single-center, cross-over pilot study evaluated 31 subjects aged 18–44 years with normal eyes and good tear film stability who were adapted current soft contact lens wearers. Subjects wore nelfilcon A and stenfilcon A DDCLs for 12 hours each on two different days. Non-invasive video keratography drying-up time (NIK-DUT) videos of each eye were recorded 12 hours after lens insertion for about 25 seconds, with a 5-minute tear film recovery time allowed between video recordings of the right and left eyes to avoid bias. Post-blink time required to reach 15% distortion of the projected rings and the speed of break-up at 15 seconds post-blink were measured at each time point and on-eye wettability was determined by ring mire projection under white light illumination.ResultsMean time to reach 15% ring distortion was similar for nelfilcon A (19.25±3.20 sec) and stenfilcon A (20.24±3.02 sec) DDCLs but varied highly among subjects. The mean speed of break-up at 15 sec post-blink was 0.3±0.38% distortion/sec (95% confidence interval [CI] 0.138–0.365% distortion/sec) for nelfilcon A and 0.2±0.23% distortion/sec (95% CI 0.048–0.279% distortion/sec) for stenfilcon A DDCLs.ConclusionMultifunctional topography allowed the objective evaluation of in vivo pre-lens tear film stability using ring mire projection. This dynamic method was simple, fast and non-invasive, enabling measurements of NIK-DUT and evaluating wettability over a large area, greater than the optical zone of the contact lens surface, for the entire inter-blink interval.

Subjective Comparison of Pre-Lens Tear Film Stability of Daily Disposable Contact Lenses Using Ring Mire Projection.

PurposeTo subjectively evaluate the in vivo tear film stability of three daily disposable contact lenses (DDCLs) using placido ring reflection at lens wear times of 5 mins and 8 and 12 hrs.Patients and MethodsThis prospective, randomized, observer-masked, 3-way crossover study evaluated 28 subjects with good tear film stability. In vivo tear film stability was assessed for three DDCLs (nelfilcon A, etafilcon A, omafilcon A) on three different days over 12 hrs of lens wear. Time to first distortion by non-invasive keratography drying-up time (NIK-DUTf) was assessed by reviewing the captured videos. Lens wettability was also graded subjectively by three investigators using a scale from 0 (no visible distortions) to 3 (distortions in more than one-third of the ring reflection zone). Medians were analyzed statistically.ResultsMean NIKDUTf at 8 hrs was longer for nelfilcon A and shorter for etafilcon A and omafilcon A, but the differences were not significant. NIK-DUTf did not differ significantly among nelfilcon A, etafilcon A and omafilcon A DDCLs at all visits (p=0.36). Subjective wettability grades after 5 mins, 8 hrs, and 12 hrs differed significantly for etafilcon A (P <0.01) and omafilcon A (p < 0.01), but not for nelfilcon A (p = 0.05), DDCLs.ConclusionGrading was sufficiently sensitive to differentiate the wettability performances of the three lens materials. Nelfilcon A maintained wettability over the wearing period, whereas etafilcon A material showed faster dewetting at 8 and 12 hrs than at 5 mins after lens insertion.

Low levels of ex vivo total cholesterol extraction and the maintenance pre-lens tear film stability and comfort with EOBO regimen throughout 30 days of lens wear

Purpose: To investigate the total extracted ex vivo cholesterol, daily comfort, and pre-lens tear film stability over a period of 30 days with lotrafilcon B lenses packaged in blister solution containing EOBO (polyoxyethylene-polyoxybutylene) wetting agent, cared for with H2O2 lens care solution containing EOBO (Regimen1) or MPS solution containing EOBO (Regimen2).

Impact of Air Exposure Time on the Water Contact Angles of Daily Disposable Silicone Hydrogels.

The wettability of silicone hydrogel (SiHy) contact lens (CLs) is crucial for the pre-lens tear film stability throughout the day. Therefore, sessile drop and captive bubble setups were used to study the advancing and receding water contact angles (CA) of four SiHy materials: narafilcon A (TE), senofilcon A (AOD), stenfilcon A (MD), and delefilcon A (DT). TE and AOD have 48% and 38% water content, respectively, and no surface coating. MD (54% water) implements “smart chemistry” with just 4.4% bulk silicone content, while DT has >80% water at its surface. These SiHy were subjected to continuous blink-like air exposure (10 s)/rehydration (1s) cycles for 0, 1, 2, 3, 4, 6, 8, 10, 12, 14, and 16 h. The advancing CA, which measures the rehydration propensity of the CL surface, proved to be the most sensitive parameter to discriminate between the samples. The order of performance for the entire time scale was DT > MD >> AOD ≥ TE. The extended desiccation/rehydration cycling increased the differences between the CA of DT and MD compared to AOD and TE. This suggests that the low Si surface content and the high surface hydration are major determinants of SiHy wettability.

Effects of three different daily disposable contact lenses on tear film

Purpose: To evaluate changes induced by three different daily disposable CLs on tear osmolarity (TFO), tear meniscus height (TMH), pre lens tear film stability (PLTFS) and objective quality of vision.

Comparison of pre-lens tear film stability with daily disposable contact censes using ring mire projection with automatic assessment

Comparison of pre-lens tear film stability with daily disposable contact censes using ring mire projection with automatic assessment

Effects of Lens-Care Solutions on Hydrogel Lens Performance.

Lens care multipurpose solutions (MPSs) can have varying effects on contact lens (CL) surface properties and the corneal epithelium. The aim of this study was to investigate the short-term effects of newer MPS on CL comfort and dryness, prelens tear-film stability, and ocular-surface health. In vitro study was also performed to assess the effect of MPSs on CL surface properties. Acuvue 2 CLs were soaked in control solution, Clear Care (CC), or test solutions: PureMoist, Biotrue, RevitaLens (RL), or saline solution (SS). Over four visits, subjects were exposed to control solution in one eye and to test solution in the contralateral eye for 2 hours using presoaked CLs. Contact lens comfort and dryness, ocular-surface health assessment, prelens noninvasive tear breakup time, and corneal epithelial permeability measured with fluorometry were assessed. Captive-sessile bubble technique evaluated CL wettability and viscous drag in vitro. At 10 minutes, mean comfort ± SD with PureMoist (76 ± 22) was lower than CC (86 ± 15, P = .02), Biotrue (92 ± 9, P < .005), RL (90 ± 13, P < .005), and SS (90 ± 14, P < .005). No other difference in comfort or dryness was noted. RevitaLens was associated with greater corneal epithelial permeability than CC (P = .020) and increased corneal staining compared with all MPSs (P < .005 for all). RevitaLens was also associated with longer prelens noninvasive tear breakup than CC (P < .005). In vitro results agreed with clinical findings of tear-film stability as RL reduced viscous drag. Contact lens surface wettability was enhanced by all MPSs in comparison to SS. Differences of MPSs on the ocular surface were found in vivo and in vitro. RL caused the greatest corneal epithelium disruption but also associated with higher tear-film stability. The effect of MPSs on CL surface properties in vitro seems to reflect how MPSs altered prelens tear stability.

Effect of contact lens surface properties on comfort, tear stability and ocular physiology.

Retrospective analysis of different contact lens wearing groups suggests lens surface lubricity is the main factor influencing contact lens comfort. However, the examined commercially available contact lenses differ in material and design as well as surface properties. Hence this study isolates the contribution of lens surface properties using an ultra-thin coating technology. Nineteen habitual contact lens wearers (21.6±1.7years) wore formofilcon B soft monthly disposable contact lenses with and without coating technology modified surface properties for a month each in a randomised double-masked cross-over study. OBJECTIVE NON-INVASIVE: breakup time (NIKBUT), NIKBUT average and ocular redness (Jenvis grading scale) were evaluated (Keratograph 5M) after 1 week and 1 month of wear. Symptoms were assessed using the Contact Lens Dry Eye Questionnaire (CLDEQ-8); perceived vision quality and subjective lens comfort at insertion, mid-day and end of the day were rated with four Visual Analog Scales. Perceived visual quality (F=5.049,p=0.037), contact lens dry eye symptoms (F=14.408,p=0.001) and subjective lens comfort (F=28.447,p<0.001) were better for coated compared to uncoated lenses. The surface coating postponed the lens dewetting (F=8.518,p=0.009) and increased the pre-lens tear film stability (F=5.626,p=0.029), but bulbar (F=0.340,p=0.567) and limbal (F=0.110,p=0.744) redness were similar for both contact lenses. No parameter changed significantly between a weeks' and months' wear (p>0.05). Lens surface wettability and ocular redness were not correlated to changes in symptoms (p>0.05). As previously hypothesised, enhancing the physical surface properties of a soft contact lens improves subjectively rated wearer comfort, which, in turn, should result in reduced contact lens discontinuation.

Subjective pre-lens tear film stability of daily disposable contact lenses using ring mire projection

Subjective pre-lens tear film stability of daily disposable contact lenses using ring mire projection

Soft Lens Lubricants and Prelens Tear Film Stability

Soft contact lens wearers complaining of "dry eye" are frequently prescribed rewetting drops, although the mode of action and efficacy of this treatment have not been established. Enhancement of prelens tear film (PLTF) stability could provide a basis for symptomatic relief with solution instillation. Thirty symptomatic hydroxyethyl methacrylate (HEMA) lens wearers participated in 4 separate trials of no solution (baseline), saline, and 2 soft lens lubricants. Solutions were applied for a 6-h adaptation period, and PLTF noninvasive break-up time (NIBUT) was monitored for 1 h after a final instillation. PLTF NIBUT was significantly elevated 1 min after instillation of all solutions (p less than 0.001, logrank test) but this effect persisted for less than 5 min. The transient enhancement of PLTF stability arising from the instillation of these rewetting solutions is unlikely to provide a basis for prolonged symptomatic relief.