Profiling of non-polar lipids in tears of contact lens wearers during the day.

PURPOSE: This study explored whether the non-polar lipids in the human tear fluid lipidome show diurnal variation with and without contact lens wear. It also addressed the relationship between changes in ocular comfort during the day with the level of non-polar lipids. METHODS: Tear samples were collected in the morning and evening with and without contact lenses using fine glass capillary tubes and were analysed by chip-based nano-electrospray ionization tandem mass spectrometric techniques. Tear levels of cholesteryl esters (CE), wax esters (WE) and triacylglycerides (TAG) were quantified. RESULTS: TAG 48:0, 52:0 and WE 26:0/16:0, and 27:0/17:0 increased from morning to evening. TAG 52:2, WE 21:0/16:0, 21:0/18:1 and 28:0/18:1 decreased during the day when no lenses were worn. CE 21:0 was the only non-polar lipid that increased from morning to evening in contact lens wear. WE 21:0/16:0 and 27:0/17:0 were lower in the morning in contact lens wear compared to no lens wear (p ≤ 0.05). The level of non-polar lipids did not correlate with ocular comfort at the end of the day. CONCLUSION: Even though the level of some of non-polar lipid species changed from morning to evening the total level of major tear non-polar lipids remained unchanged during the day with and without contact lens wear. The effect of change in the quantity and structure of lipid species on tear stability and ocular comfort warrants more investigation.

Application of superficial keratectomy and soft contact lens for the treatment of symblepharon in a cat: a case report.

A 7-month-old intact female Persian cat was diagnosed with symblepharon accompanied by epiphora, brownish ocular discharge, and ocular discomfort in the left eye. Superficial keratectomy (SK) was performed to remove adhesions between the conjunctiva and cornea. To prevent re-adhesion after SK, the detached conjunctival tissue was sutured to the corneal limbus, and a soft contact lens (SCL) was inserted and a partial temporary tarsorrhaphy was performed. The SCL and tarsorrhaphy sutures were maintained for 22 days, and symblepharon did not recur 347 days postoperatively. SK combined with SCL is a relatively easy and cost-effective surgical option for feline symblepharon.

Soft contact lens wearers' compliance during the COVID-19 pandemic.

AIM: Contact lens wearers need to maintain optimal hygiene practices during the COVID-19 pandemic to minimise contact-lens complications including microbial keratitis and corneal infiltrative events. This online survey (UK and Ireland) explored contact lens wearers' compliance behaviours, attitudes and concerns during the pandemic. METHOD: The 60-item anonymous online survey was distributed during a 1-month period via Qualtrics (starting on 14/04/20). The survey captured: a) demographic information, b) type of lenses worn and compliance with lens wear and care procedures, c) adherence to recommendations and d) concerns associated with contact lens wear during the pandemic. RESULTS: Two hundred and forty seven responses were received (34.3 ±â€¯11.7 years old, 79% female). Seventy nine percent of participants reported that they were self-isolating or rigorously following social distance advice. Fifty-six percent of participants reported using their lenses less during the pandemic. Eighty-seven percent of respondents reported following the recommended 20-second rule most times/every time and 96% used soap and water during handwashing. Eleven percent of respondents admitted not following recommendations regarding disposal of lenses and 18% would not consider ceasing lens wear if unwell (with flu/cold) during the pandemic. CONCLUSION: Respondents reported wearing their contact lenses less than usual. Good compliance with handwashing was observed but soft reusable lens wearers showed a statistically significant lower compliance with lens wear and care compared to daily disposable lens wearers (p=<0.001).

Influence of the COVID-19 pandemic on contact lens wear in Spain.

PURPOSE: To investigate the behaviour of contact lens (CL) wearers in Spain during the COVID-19 pandemic. METHODS: An anonymized web-based questionnaire was used to assess demographics, CL history, and activity, CL wear habits and perceived risk of infection due to CL wear during the COVID-19 pandemic. RESULTS: A total of 737 participants with an average age of 27.4 (±9.3) years completed the online questionnaire. The vast majority of respondents were soft CL wearers and reported at least two years of CL wear. Patients concerns about the increased risk of SARS-CoV-2 infection due to CL wear (40.6 % of participants) were significantly related (χ2(1) = 11.195, p < 0.05) to CL discontinuation (46 % of participants) during the COVID-19 pandemic. This fact joins the significant changes in the frequency of CL wear during the COVID-19 pandemic (χ2(4) = 31.982, p < 0.05), with a tendency to increase occasional CL wear from 29.1 % to 61.8 %. Interestingly, the majority of respondent (87.9 %) indicated that no professional had offered them information related to CL wear and COVID-19, and that they had not sought it on their own (82.2 %). CONCLUSION: There is a relationship between the perceived risk of infection and CL dropout during the COVID-19 pandemic, and a tendency to change the CL frequency of wear, with an increase in occasional CL wear. During the ongoing pandemic, eye care practitioners should reinforce CL patient education to minimize the risk of SARS-CoV-2 infection and CL-related complications requiring clinical care.

Childhood and lifetime risk comparison of myopia control with contact lenses.

PURPOSE: The relative risks of ocular pathology with increasing myopia have been described; the absolute lifetime risk of vision impairment from myopia is yet to be compared to the childhood and lifetime risks of contact lens wear for myopia control. METHODS: Using peer-reviewed data, the absolute risks of microbial keratitis (MK) in daily disposable soft, reusable soft and orthokeratology contact lens (CL) wear were calculated over both a childhood (age 8-18) and a lifetime (age 8-65) of CL wear. This was compared to the previously published cumulative risk of vision impairment by age 75 based on increasing myopia and axial length. Data were converted utilizing the Council of International Organizations of Medical Sciences (CIOMS) classification system for frequency of adverse events, with 95 % confidence intervals included. RESULTS: The lifetime risk of vision impairment in axial lengths over 26 mm and more than 6D of myopia is greater than the lifetime risk of MK in any CL modality, except for adult SCL extended wear. If axial length is below 26 mm and myopia lower than 3D, a lifetime of CL wear is more risky in comparison, except in the case of daily disposable wear. Ten years of childhood CL wear of any modality presents lower likelihood of MK than any comparable risk of vision impairment. CONCLUSION: The comparative lifetime risks of contact lens wear commenced at age 8 for myopia control are less than the lifetime risks of vision impairment with myopia more than 6D or axial length more than 26 mm. When only childhood CL wear is considered, the risk comparison is clearly skewed towards the positive impact of CL wear, especially in daily disposable wear. Clinicians should be confident to proactively recommend myopia control CL wear to younger children, as both the safety profile and potential preventative ocular health benefits are evident.

Safety of soft contact lenses in children: retrospective review of six randomized controlled trials of myopia control.

PURPOSE: To examine the rate and types of ocular adverse events among children wearing soft contact lenses. METHODS: This study is a retrospective review of ocular adverse event data from six randomized controlled trials among a total of 581 myopic children (aged 7-15 years at baseline) administered daily disposable hydrogel contact lenses (etafilcon A). RESULTS: During 816 patient years of contact lens wear, no significant or serious ocular adverse events were reported. A total of 86 non-significant ocular adverse events occurred in 53 children. The crude rate of ocular adverse events was 10.6 per 100 patient years with the estimated pooled incidence being 8.9 per 100 patient years (95% CI: 4.5-17.4). Two asymptomatic corneal infiltrative events were reported (both non-significant), which is an incidence of 0.3 (95% CI: 0.1-0.9) per 100 patient years. The most common ocular adverse events (n) were slit-lamp findings of Grade 2 or less requiring treatment (26), unspecified conjunctivitis (14), and allergic conjunctivitis (13). No cases of microbial keratitis were observed. Of the 86 adverse events, 37 were classified as highly likely or possibly lens-related, giving a crude incidence of 4.5 per 100 patient years for contact lens-related events. The crude incidence of ocular adverse events among spectacle wearers was 1.8 per 100 patient years. CONCLUSION: These data suggest that daily disposable soft contact lenses can be safely worn by children. Additional studies will be needed to precisely quantify the adverse event rate of soft contact lenses in normal clinical practice.

A study of contact lens compliance in a non-clinical setting.

PURPOSE: To evaluate soft contact lens replacement, overnight (ON) wear, and contact lens case compliance in a non-clinical sample. METHODS: Subjects (n = 297) were recruited at the Center for Science and Industry (COSI) in Columbus, Ohio. Adult (≥ 18 years) soft contact lens wearers completed a survey about contact lens replacement, ON contact lens wear, and contact lens case replacement habits. RESULTS: Two-week replacement lenses (according to the manufacturer's replacement schedule [MRS]) were most common (45.5%), followed by monthly (34.3%) and daily replacement (20.2%). Non-compliance with replacement schedule was reported in 38.7% of subjects. Age (p = 0.02), years of lens wear (p = 0.02), and MRS (p <0.0001) affected replacement compliance. Post-hoc analysis showed daily replacement wearers were more compliant than two-week (p <0.0001) and monthly (p <0.0001) replacement wearers with prescribed lens replacement. Non-compliance with prescribed ON wear was reported in 23.9% of subjects. Subjects who were non-compliant with lens replacement were more likely to be non-compliant with ON wear (p = 0.02) and had worn contact lenses for less time (p = 0.02). Of the subjects who used contact lens cases, 74.6% were unsure when they should replace their case. Frequency of case replacement was not associated with age (p = 0.5), gender (p = 0.5), years of contact lens wear (p = 0.7), MRS (p = 0.4), replacement compliance (p = 0.3), or ON wear compliance (p = 0.7). CONCLUSIONS: Daily replacement wearers were most likely to be compliant with contact lens replacement, but all subjects, including daily replacement wearers, had similar ON wear non-compliance. Non-compliant lens replacement was associated with non-compliant ON wear, but contact lens case replacement was not related to either compliance category. The majority of subjects had no knowledge of proper contact lens case replacement, despite compliance in other categories.

Relationship Between Contact Lens and Pinguecula.

PURPOSE: To investigate the effects of contact lens (CL) on the frequency of pinguecula, and the relationship between dry eye disease and pinguecula. METHODS: Two hundred and 33 cases of soft CL wearers and 230 age-matched nonwearers were enrolled in the study. Schirmer I test (ST) scores and tear break-up time (TBUT) were determined in all participants. A questionnaire including ocular surface disease index (OSDI), age, sex, and duration of CL wear was implemented to the participants before the examination. RESULTS: The prevalence of pinguecula was 27.8% (n: 65) in the CL group and 26.5% (n: 61) in the control group. There was no significant difference between the groups (P=0.841). The prevalence of pinguecula increased with age in both groups. There was no significant difference in the prevalence of pinguecula when users were divided into three groups according to the duration of CL wear (P=0.575). The TBUT scores were lower, and the OSDI scores were higher in the CL group. The TBUT scores were lower in patients with pinguecula in both groups. The OSDI scores were higher in the CL group. There was no significant difference regarding the OSDI scores between patients with pinguecula and healthy participants in the CL group; however, OSDI scores were significantly higher in patients with pinguecula in control group. There were no significant differences in the ST scores between the groups, and between patients with pinguecula and healthy participants. CONCLUSION: This is the second study that evaluates the effects of soft CL wearing on pinguecula prevalence. We found that CL wearing does not affect the prevalence of pinguecula. Considering the OSDI scores in patients with pinguecula in the CL group, CL may suppress the irritant symptoms of pinguecula.

Influence of Sodium Hyaluronate Concentration on Corneal Aberrations in Soft Contact Lens Wearers.

PURPOSE: This study aimed to evaluate the influence of varying concentrations of sodium hyaluronate (SH) eye drops on corneal aberrations in normal individuals wearing silicone hydrogel contact lenses. METHODS: Normal individuals wearing silicone hydrogel contact lenses were enrolled in this study. Subjects were classified into two groups depending on the concentration of the preservative-free SH used (group 1, 0.1% SH; group 2, 0.3% SH). All subjects were asked to blink five times after instillation of the SH eye drop and before the Galilei measurements. Corneal aberrations were measured over the contact lenses before and after SH eye drop instillation. Visual acuity (VA) over the contact lenses was also measured both before instillation of the SH eye drop and after the subjects completed the five blinks. RESULTS: There was no change in VA after SH instillation in group 1; however, group 2's VA significantly deteriorated after SH instillation. Changes in VA after SH instillation compared to baseline were significantly higher in group 2 than in group 1. Similarly, the increase in corneal aberrations after SH instillation was significant in group 2 but not significant in group 1. Among the significantly increased corneal aberration parameters, defocus was the main type in group 2. Changes in corneal aberrations after SH instillation compared to baseline were significantly higher in group 2 than in group 1. CONCLUSIONS: A 0.3%-concentration of SH increases corneal aberration and decreases VA in soft contact lens wearers. Defocus is the main type of aberration that increased in the 0.3% SH instillation group.

[TREATMENTS FOR SLOWING THE PROGRESSION OF MYOPIA].

INTRODUCTION: Myopia is the most common refractive error and is now endemic over the entire industrial world, particularly in Asia. High myopia is one of the major causes of blindness in the world. Slowing the progress of myopia is possible, the most effective treatment being atropine ophthalmic drops, given in a dose-dependent fashion. Although high-dose atropine (1% and 0.5%) was found to be highly effective in slowing myopia progression, low-dose atropine (0.01%) was found to have the lowest rebound effect (accelerated myopia progression after treatment cessation) and was therefore, the most effective treatment in the long term. Moderately effective treatments include pirenzepine drops, cyclopentolate drops, orthokeratology, contact lenses which are designed to reduce the peripheral hyperopic blur and distance-center soft multifocal contact lenses. Less effective treatments include multifocal spectacle lenses, bifocal spectacle lenses, bifocal soft contact lenses and outdoor activity in daylight. Visual therapy, biofeedback, full-spectacle correction, under-correction, spectacles designed to reduce the peripheral hyperopic blur, single-vision rigid gas-permeable contact lenses, single-vision soft contact lenses, tropicamide drops and timolol drops were all found to be ineffective.

Focal limbal stem cell deficiency associated with soft contact lens wear.

OBJECTIVE: The aim of this study is to summarize the clinical characteristics of patients with contact lens-associated focal limbal stem cell deficiency (FLSCD) from a tertiary corneal referral centre. DESIGN: Retrospective, observational case series in a tertiary care centre. METHODS: Patients with contact lens-associated FLCSD were identified in our database. Clinical data were retrieved by chart review. A questionnaire asking for contact lens brand, type, cleaning solution, and duration of contact lens wear was sent to the patients with telephone follow-up. Clinical features and recovery time were identified. RESULTS: Twenty-seven eyes of 17 patients were identified with superior corneal whorl-like patches of opaque epithelium, sometimes accompanied by neovascularization. Of the patients, 17/17 used soft contact lenses, with a mean wearing duration of 11.4 hours per day. Patients had been wearing lenses for an average of 18.1 years. Silicone hydrogel lenses were noted in 12/17 cases. LSCD was superior in all 27 eyes, and all of them improved with contact lens wear cessation, preservative-free topical steroids, and preservative-free artificial tears. Visual acuity improved from 20/28 to 20/22 (p < 0.001). CONCLUSIONS: Contact lens-associated FLSCD typically presents in the superior cornea with whorl-like epithelial opacities advancing from the limbus. Conservative medical treatment is available and shows a high success rate after a slow recovery.

Tear film evaluation and management in soft contact lens wear: a systematic approach.

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.

The effect of previous soft contact lens wear on corneal refractive surgery outcomes.

PURPOSE: To examine the influence of previous soft contact lens (SCL) wear on corneal refractive surgery (CRS) outcomes when SCL wear is ceased for two weeks versus twenty-four hours, and also when compared to no wear, prior to CRS. METHODS: A retrospective examination of CRS patient records was carried out for two groups of patients- who ceased SCL wear for two weeks (n=45) and for twenty-four hours (n=49) prior to CRS and compared to a non-contact lens (NCL) control group (n=45 and n=49, respectively). CRS outcomes (efficacy, predictability, visual acuity and refractive error) were compared pre-operatively and one and six months post-operatively. RESULTS: One month post-operative results found unaided distance visual acuity (UDVA) was significantly better for LASEK/PRK patients who had ceased SCL wear for two weeks prior to CRS (-0.05±0.09), compared with the NCL group (0.02±0.09; p=0.04). Furthermore, six month post-operative results found UDVA was significantly better for both LASIK and LASEK/PRK patients who had ceased SCL wear for two weeks prior to CRS, and for LASEK/PRK patients who had ceased SCL wear for twenty-four hours prior to CRS compared with the NCL group. CONCLUSIONS: Given the current setup and methods followed, it was concluded that previous SCL wear had no negative impact on visual outcomes following CRS compared with a NCL control group, regardless of previous SCL cessation time prior to CRS.

Water Exposure is a Common Risk Behavior Among Soft and Gas-Permeable Contact Lens Wearers.

PURPOSE: To understand soft contact lens (SCL) and gas-permeable (GP) lens wearers' behaviors and knowledge regarding exposure of lenses to water. METHODS: The Contact Lens Risk Survey (CLRS) and health behavior questions were completed online by a convenience sample of 1056 SCL and 85 GP lens wearers aged 20 to 76 years. Participants were asked about exposing their lenses to water and their understanding of risks associated with these behaviors. Chi-square analyses examined relationships between patient behaviors and perceptions. RESULTS: GP lens wearers were more likely than SCL wearers to ever rinse or store lenses in water (rinsing: 91% GP, 31% SCL, P < 0.001; storing: 33% GP, 15% SCL P < 0.001). Among SCL wearers, men were more likely to store (24% vs. 13%, P = 0.003) or rinse (41% vs. 29%, P = 0.012) their lenses in water. Showering while wearing lenses was more common in SCL wearers (86%) than GP lens wearers (67%) (P < 0.0001). Swimming while wearing lenses was reported by 62% of SCL wearers and 48% of GP lens wearers (P = 0.027). Wearers who rinsed (SCL; P < 0.0001, GP; P = 0.11) or stored lenses in water (SCL; P < 0.0001, GP P = 0.007) reported that this behavior had little or no effect on their infection risk, compared with those who did not. Both SCL (P < 0.0001) and GP lens wearers (P < 0.0001) perceived that distilled water was safer than tap water for storing or rinsing lenses. CONCLUSIONS: Despite previously published evidence of Acanthamoeba keratitis' association with water exposure, most SCL, and nearly all GP lens wearers, regularly expose their lenses to water, with many unaware of the risk.

Patient-Reported Wearing Experience From Hydrogel Daily Disposable Wearers Older Than 40 Years From the TEMPO Registry.

OBJECTIVES: To describe the patient-reported wearing experience over time among wearers of hydrogel daily disposable (HydDD) contact lenses (CLs) in the TruEye and Moist Performance Overview (TEMPO) Registry (NCT01467557). METHODS: Registered wearers older than 40 years who were recently fit with 1-DAY ACUVUE MOIST HydDDs completed self-administered questionnaires four times during a year-long Registry. Overall opinion of CLs, replacement schedules, Contact Lens Dry Eye Questionnaire (CLDEQ-8), and compliance were queried. Data were analyzed with analysis of variance and signed rank tests. RESULTS: A total of 86 subjects (24% men, age 50.2±7.1 years) completed the Registry. Approximately 76% were new to daily disposable lenses, and 8% were neophytes. Overall opinion of CLs improved significantly after refitting with HydDDs (baseline 57% excellent/very good vs. 69%-79% at follow-ups, P<0.05 all vs. baseline). Changing to HydDDs maintained average and comfortable wear time (P>0.05), and it did significantly improve CLDEQ-8 scores at all follow-ups (baseline, 11.2±7.3 vs. 2 weeks, 7.8±5.8, P<0.0001; 4 months, 8.6±6.5, P=0.0006; 12 months, 9.3±6.5, P=0.01). Self-assessment of compliance was excellent/very good for 80% at baseline, and improved to 92% to 98% at follow-ups (P<0.0001). More than 90% never slept in their HydDDs, although compliance to daily replacement diminished from 2-week to 4-month surveys (93% vs. 84%, P=0.007). CONCLUSIONS: After refitting with HydDDs, older wearers reported significantly higher overall opinions of their lenses, better CLDEQ-8 symptom scores, and most were compliant with proper daily disposable lens use. Diminishing daily replacement rates from 2 weeks to 4 months indicate a need to reinforce that recommendation. Wearers of HydDD CLs older than 40 years experienced many benefits from refitting with these daily disposable lenses.

Is purchasing lenses from the prescriber associated with better habits among soft contact lens wearers?

PURPOSE: To compare the habits of United States (US) soft contact lens (SCL) wearers who bought SCLs from their eye care practitioner (ECP), on the internet/telephone, or at retail (not where they were examined) to test the effect of proximity to the prescriber on SCL wear and care practices. METHODS: Adult SCL wearers completed an adapted Contact Lens Risk Survey (CLRS) online that queried items related to risk factors for SCL-related complications. Responses from subjects who purchased at the ECP, via the internet/telephone, or at a retail store were compared (Chi-Square). RESULTS: Purchase sources were: ECP 646 (67%, 44±12 yrs, 17% male), Retail 104 (11%, 45±13 yrs, 28% male), and Internet/telephone 218 (23%, 45±12 yrs, 18% male); age (p=0.51), gender (p=0.021). Internet purchasers had fewer annual eye exams (79% ECP, 83% retail, 66% internet/telephone, p=0.007), purchased more hydrogel SCLs (34% ECP, 29% retail, 45% internet/telephone, p=0.0034), and paid for SCLs with insurance less often (39% ECP, 29% retail, 19% internet/telephone, p<0.0001). Other behaviors were similar across groups (p>0.05). CONCLUSIONS: In this sample, the purchase location of SCL wearers had limited impact on known risk factors for SCL-related complications. Internet purchasers reported less frequent eye exams and were more likely to be wearing hydrogel SCLs. Closer access to the ECP through in-office SCL purchase did not improve SCL habits or reduce the prevalence of risk behaviors.

Effect of Environmental Conditions on the Concentration of Tear Inflammatory Mediators During Contact Lens Wear.

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-1ß, IL-2, IL-4, IL-6, and IL-8; tumor necrosis factor (TNF) α; 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-1ß (-0.48; 95% CI, -0.84 to -0.12) and IL-2 (-0.48; 95% CI, -0.87 to -0.09) 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-1ß, IL-2, IL-6, and TNF-α changes were significantly higher (P ≤ 0.04) under the adverse condition. Additionally, IL-1ß significantly decreased with comfilcon A (-0.51; 95% CI, -0.88 to -0.15), being significantly lower (P = 0.01) than the change with omafilcon A (0.06; 95% CI, -0.23 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.

Effect of Short Recovery Periods on Ocular Comfort During Daily Lens Wear.

PURPOSE: To assess the impact of lens-free intervals of varying lengths on end-of-day comfort with soft contact lenses. METHODS: Twenty-five symptomatic lens wearers participated in this randomized, cross-over study involving nine individual 12-hour days: one spectacle (no lens) and eight lens wear days. On each lens wear day, lenses were worn bilaterally in 2-hour intervals, separated by lens-free (recovery) periods of 0, 30, 60, or 80 minutes (repeated throughout the day). For each 2-hour lens wear interval, new lenses were worn. Ocular comfort was rated on a 0 to 100 visual analogue scale (0 = extremely uncomfortable); tear film and ocular parameters were assessed at the beginning and end of each study day. This study involved two different types of silicone hydrogel lenses, and the order of lens type and length of recovery period was randomized. Participants were unaware of the true study purpose and that a new lens pair was used for each lens wear interval. RESULTS: End-of-day comfort on lens wear days was significantly worse than on the spectacle day (p < 0.002). There was no significant effect of the recovery periods on end-of-day comfort (p > 0.05). Although lens wear affected noninvasive tear film break-up time and conjunctival staining, there were no effects of recovery period length on noninvasive tear film break-up time (p > 0.05), tear meniscus height (p > 0.05), corneal staining (p > 0.05), conjunctival staining (p > 0.05), bulbar conjunctival redness (p > 0.05), or limbal redness (p > 0.05). There was no consistent effect of recovery period length on lid margin staining. CONCLUSIONS: Lens-free recovery periods during a 12-hour lens wear day did not positively impact end-of-day comfort in this study. Cumulative lens wear times ranged from 8 to 12 hours, and the results suggest that once the length of lens wear exceeds the usual comfortable wear time, there is no benefit of short recovery periods.

Diurnal Variation in Comfort in Contact Lens and Non-contact Lens Wearers.

PURPOSE: The purpose of this investigation was to evaluate the diurnal variation in symptoms associated with ocular discomfort in contact lens (CL) wearers and non-CL wearers. METHODS: The study population comprised 604 individuals attending pre-screening visits at the OTG-i research clinic; 60% were current soft CL wearers (hydrogel and silicone hydrogel) and 40% were non-CL wearers. Symptomatology status was determined by the OSDI questionnaire (58% asymptomatic, 42% symptomatic). Participants were asked to grade their comfort, vision, and other symptoms during the day and in the evening (before lens removal for CL wearers) on 0 to 100 visual analogue scales. RESULTS: Diurnal decrease in comfort was significantly greater for CL wearers (-16.0 vs. -6.3, p < 0.001) and symptomatic participants (p = 0.015). Diurnal decrease in subjective vision was also significantly greater for CL wearers (-10.4 vs. -6.9, p = 0.005) and symptomatic participants (p = 0.001), and the interaction between these factors was also significant (p = 0.019). Dryness, grittiness, and irritation increased significantly more for CL wearers (p < 0.001, p = 0.012, and p = 0.004, respectively) and grittiness, irritation, and stinging for symptomatic participants (p = 0.016, p < 0.001, and p < 0.001, respectively). For the CL wearers, there was a significant interaction between dryness and age (p = 0.026) with the diurnal increase in dryness being greater in those under 40 (+15.6 vs. +10.0). CONCLUSIONS: The diurnal decrease in comfort and subjective vision, and the diurnal increase in dryness, grittiness, and irritation, were significantly more marked for CL wearers than non-CL wearers. Diurnal changes in comfort, grittiness, stinging, irritation, and vision were influenced by the subject's overall symptomatology as assessed by the OSDI questionnaire. For dryness symptoms, the diurnal decrease was most marked in young CL wearers. For the symptoms of stinging and vision, the diurnal changes were most pronounced in the symptomatic groups.

Development of the Contact Lens User Experience: CLUE Scales.

PURPOSE: The field of optometry has become increasingly interested in patient-reported outcomes, reflecting a common trend occurring across the spectrum of healthcare. This article reviews the development of the Contact Lens User Experience: CLUE system designed to assess patient evaluations of contact lenses. CLUE was built using modern psychometric methods such as factor analysis and item response theory. METHODS: The qualitative process through which relevant domains were identified is outlined as well as the process of creating initial item banks. Psychometric analyses were conducted on the initial item banks and refinements were made to the domains and items. Following this data-driven refinement phase, a second round of data was collected to further refine the items and obtain final item response theory item parameters estimates. RESULTS: Extensive qualitative work identified three key areas patients consider important when describing their experience with contact lenses. Based on item content and psychometric dimensionality assessments, the developing CLUE instruments were ultimately focused around four domains: comfort, vision, handling, and packaging. Item response theory parameters were estimated for the CLUE item banks (377 items), and the resulting scales were found to provide precise and reliable assignment of scores detailing users' subjective experiences with contact lenses. CONCLUSIONS: The CLUE family of instruments, as it currently exists, exhibits excellent psychometric properties.