Soft Contact Lens-Related Symptoms in North America and the United Kingdom

End-of-day assessment of asymptomatic versus highly symptomatic soft contact lens wearers

PURPOSE

To investigate differences in key clinical parameters between asymptomatic and highly symptomatic soft contact lens (CL) wearers after 14 h of wear.

METHODS

In this pilot investigation, Phase 1 identified asymptomatic (CLDEQ-8 score ≤ 7) and highly symptomatic (CLDEQ-8 score ≥ 20) subjects after fitting with nelfilcon A CLs. Phase 2 investigated the following over a single nelfilcon A CL-wearing day (14 ± 2 h): blinking characteristics, tear meniscus height (TMH), non-invasive tear break-up time (NIBUT), tear film osmolarity and eyelid margin staining. Parameters for the two groups were compared using linear mixed models and post-hoc testing. The relationship between comfort scores and the clinical parameters was also investigated.

RESULTS

Overall, 161 and 42 subjects were enrolled into Phase 1 and 2, respectively. Twenty-five asymptomatic and 17 symptomatic subjects completed Phase 2. Lower eyelid TMH was decreased after 14 h in symptomatic compared with asymptomatic subjects (least square mean [LSM] difference -0.04 mm, 95% CI: -0.07, -0.01). Osmolarity was lower in symptomatic than in asymptomatic subjects at fitting (LSM difference -9.89, 95% CI: -18.91, -0.86). Upper eyelid margin staining was greater after 14 h in symptomatic than in asymptomatic subjects (LSM difference 0.53, 95% CI: 0.01, 1.05) and greater after 14 h than baseline in the symptomatic group (LSM difference 0.61, 95% CI: 0.16, 1.07). There was a significant relationship between comfort and upper eyelid margin staining (r = -0.40, 95% CI: -0.63, -0.11) and blink rate (r = -0.31, 95% CI: -0.57, -0.003).

CONCLUSION

The potential parameters most effective in differentiating asymptomatic from symptomatic wearers were upper eyelid margin staining and lower TMH. The parameter with the strongest relationship to comfort was upper eyelid margin staining, where higher comfort scores were associated with lower levels of staining.

BCLA CLEAR Presbyopia: Management with contact lenses and spectacles

This paper seeks to outline the history, market situation, clinical management and product performance related to the correction of presbyopia with both contact lenses and spectacles. The history of the development of various optical forms of presbyopic correction are reviewed, and an overview is presented of the current market status of contact lenses and spectacles. Clinical considerations in the fitting and aftercare of presbyopic contact lens and spectacle lens wearers are presented, with general recommendations for best practice. Current options for contact lens correction of presbyopia include soft simultaneous, rigid translating and rigid simultaneous designs, in addition to monovision. Spectacle options include single vision lenses, bifocal lenses and a range of progressive addition lenses. The comparative performance of both contact lens and spectacle lens options is presented. With a significant proportion of the global population now being presbyopic, this overview is particularly timely and is designed to act as a guide for researchers, industry and eyecare practitioners alike.

Clinical characterisation of contact lens discomfort progression

PURPOSE

This study aimed to assess the subjective and objective differences among the steps of the contact lens discomfort (CLD) progression classification established by the Tear Film & Ocular Surface Society (TFOS) using questionnaires and clinical signs, and to propose a simplified classification.

METHODS

Contact lens (CL) wearers were evaluated in a single visit. The Contact Lens Dry Eye Questionnaire (CLDEQ)-8, the Contact Lens Discomfort Index, and Visual Analog Scales for discomfort and dryness were administered. The non-invasive break-up time, the tear film lipid layer thickness, conjunctival hyperaemia and papillae, lid-parallel conjunctival folds, the fluorescein tear film break-up time, corneal and conjunctival staining, lid wiper epitheliopathy, and the Schirmer test were assessed. Sign and symptom scores were compared among TFOS CLD progression steps using analysis of variance or the Kruskal-Wallis H test. Steps 1 and 2 (reduced comfort), and steps 3 and 4 (reduced wearing time) of the TFOS classification were combined to obtain a simplified classification, and the same comparison was performed. A p-value ≤ 0.05 was considered statistically significant.

RESULTS

One hundred-fifty CL wearers (97 women and 53 men) aged 34.4 ± 12.6 years were included. In the TFOS classification, there were significant differences between step 0 (no CLD) and the rest of the severity steps for the scores obtained in all questionnaires (p ≤ 0.015). All steps were differentiated (p ≤ 0.032) based on the simplified classification for all questionnaires, except steps 1 and 2 for the CLDEQ-8 and dryness VAS (p = 0.089 and p = 0.051, respectively). There were no differences (all p ≥ 0.06) between the sign scores among the steps of either classification.

CONCLUSION

CLD management is encouraged from its first appearance. Simplifying the phases of CLD severity may allow a more accurate classification and a better awareness of the problem by clinicians and CL wearers by using more straightforward simple messages.

Reliability and agreement of subjective and objective non-invasive break-up time measurements in contact lens wearers

PURPOSE

To assess the reliability and agreement of non-invasive break-up time (NIBUT) in symptomatic and asymptomatic contact lens (CL) wearers using automatic objective and conventional subjective techniques.

METHODS

In this prospective cross-sectional study, soft CL wearers, classified into symptomatic and asymptomatic based on the Contact Lens Dry Eye Questionnaire-8, underwent NIBUT assessment with the CL in situ. The CA-800 Corneal Analyzer and the EasyTear® VIEW+ Tearscope were used for objective and subjective evaluation, respectively. The within-subject repeatability and intraclass correlation coefficient (ICC) were calculated. The agreement between the devices was compared using the Bland-Altman method.

RESULTS

A total of 141 CL wearers (51 male and 90 female) with a mean age of 33.6 (SD = 12.2) years were included. The repeatability and ICC values obtained with the CA-800 device when measuring NIBUT were 5.4 s and 58.6% across the whole sample, 4.2 s and 48.8% for the asymptomatic group and 7.1 s and 68.4% for the symptomatic group. When using the subjective method (EasyTear®), the respective repeatability and ICC values were 7.3 s and 32.7% for the whole sample, 6.5 s and 30.4% for the asymptomatic group and 8.6 s and 35.9% for the symptomatic group. The CA-800 device provided significantly (p < 0.001) shorter NIBUT values compared with EasyTear® for the whole sample (3.3 [2.9] vs. 8.1 [3.4] s), the asymptomatic (3.3 [3.0] vs. 7.7 [3.6] s) and the symptomatic (3.8 [2.9] vs. 8.6 [3.0] s) groups.

CONCLUSION

Objective (CA-800) NIBUT assessment provides more reliable measurements than the conventional subjective technique using the EasyTear® device. However, CL practitioners should also be aware that the objective method indicates shorter NIBUT values. Symptomatic CL wearers may also need a higher number of NIBUT measurements to obtain reliable estimations.

2023 Prentice Medal Award lecture: Ocular surface-related symptoms of discomfort and other stories

ABSTRACT

I have been fortunate to spend portions of my career in each of private practice, industry, and academia. At some times, these occupations have dictated the research direction, whereas, at others, curiosity has been allowed to dominate. This has resulted in multiple avenues of inquiry (some might say, too many), along which I have traveled with a rich and varied cast of collaborators, who have all taught me a great deal. The privilege of being awarded the Charles F. Prentice medal provides me an opportunity to summarize some of these activities. Beginning with an attempt to use contact lenses to solve a problem for those affected by albinism, the story shifts to addressing some of the wider deficiencies of contact lenses, in particular the consequences of their oxygen permeability and tendency to induce discomfort toward the end of the day. After briefly considering some aspects of meibomian gland function, the narrative concludes with the latest investigations of neurological links between the cornea and migraine.

Italian translation and validation of the Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8)

PURPOSE

To translate and validate an Italian version of the CLDEQ-8 (CLDEQ-8_IT).

METHODS

The study was carried out in two phases. In the first phase, a cross-cultural adaptation of CLDEQ-8 to Italian was performed by forward and backward translation in sequence. In the second phase, a multi-centre study was conducted for the validation of the questionnaire. Validity CLDEQ-8_IT was evaluated against three gestalt questions: overall opinion of soft contact lenses (CLs), global self-assessments of eye sensitivity and eye dryness. Reliability was evaluated by test-retest assessment in a subgroup of subjects. Finally, the psychometric properties of CLDEQ-8_IT were explored by Rasch analysis.

RESULTS

Two hundred and forty soft CL wearers, fluent Italian speakers (73 males and 167 females), between 18 and 70 years of age were enrolled. A significant correlation was found between CLDEQ-8_IT and each of the three Gestalt questions. The cutoff score of 12 points demonstrated the best balance between sensitivity and specificity in differentiating wearers grading their CLs as "Excellent/Very good" from those reporting their overall opinion as "Good/Fair/Poor". The Intraclass Correlation Coefficient between test and retest was 0.88 (95% CI: 0.81-0.92). Finally, infit and outfit statistics using Rasch analysis for the 8 items were in a good range, however Principal Components Analysis revealed a certain degree of multi-dimensionality of the instrument. Also, item 8 analysis could be computed after merging the last two response categories.

CONCLUSION

The CLDEQ-8_IT showed very good validity and reliability in measuring symptoms of CL wearers, comparable to the original English language version. A cut-off of 12 was confirmed as yielding the best balance between sensitivity and specificity in detecting CL wearers who could benefit from clinical management of their CL-related symptoms. Collapsing of the response options 5 and 6 in the last item of questionnaire could optimise its functioning.

Translation and validation of the contact lens dry eye questionnaire 8 (CLDEQ-8) in Canadian French

PURPOSE

To present the process that led to the creation of the French Canadian translated version of the Contact Lens Dry Eye Questionnaire-8 (which allows for an assessment of symptoms while wearing soft contact lenses) as well as the validation data of the f-CLDEQ-8.

METHODS

The CLDEQ-8 went through the process of reverse translation, which was then reviewed and improved by an experts' committee to create a first version of the French questionnaire. Cognitive interviews were conducted to pretest the tool and ensure content validity. After a review of the pretest, the f-CLDEQ-8 was created. A web-based version of this questionnaire was sent to contact lens wearers (CLW) recruited out of a clinical setting for completion at two different endpoints interspaced by 7 days. Internal consistency and test-reliability were calculated using Cronbach's alpha and Intra-class Correlation coefficient (ICC), respectively. Convergent validity between the f-CLDEQ-8 score and overall opinion of the contact lenses was evaluated with a correlation.

RESULTS

9 CLW with different socio-economic statuses and education levels went through a cognitive interview with the back-translated version of the f-CLDEQ-8 to improve the questionnaire wording and enhance its comprehension. 63 CLW (34.2 ± 10.1 years old and 2/3 of them women) completed the f-CLDEQ-8 twice. An average Cronbach alpha of 0.928 was found and an ICC of 0.944 (CI at 95 % 0.905;0.966). A moderately strong correlation of -0.714 (CI at 95 % -0.817;-0.566) was found between the overall opinion of the contact lenses and the total score to the f-CLDEQ-8.

CONCLUSION

The French language version (f-CLDEQ-8) generated from the original CLDEQ -8 was shown to be easy to use, reliable and culturally adapted to French spoken in Canada.

Prevalence of Dry Eyes Symptoms in Association with Contact Lenses and Refractive Status in Portugal

Background: Determine whether the presence of ocular symptoms in soft-contact-lens wearers changes depending on the refractive status. Methods: During the months of January to March 2022, the CLDEQ-8 questionnaire was administered to soft-contact-lens wearers. The statistical analysis was carried out using the SPSS 27.0 computer program (SPSS Inc., Chicago, IL, USA). Results: A total of 251 subjects participated in the study, with a higher percentage of myopes than hyperopes (82.1% versus 16.7%; p < 0.001). Out of all total participants, 21.5% suffered from dry-eye symptoms. It was noted that hyperopes presented a higher rate of dry-eye symptoms (p = 0.041). At the same time, the spherical equivalent was more positive in the participants with dry-eye symptoms (p = 0.014). Significant differences were found based on the symptoms present with contact lenses and the degree of myopia. The intensity of visual disturbances was higher in the participants with medium myopia (median [IQR]: 1/5 [2]) compared to those with low (median [IQR]: 0/5 [2]) and high myopia (median [IQR]: 0/5 [1]) (p = 0.009). Conclusions: Contact-lens wearers with hyperopia showed a higher rate of ocular dryness than those with myopia. In turn, wearing daily-replacement lenses could be one of the reasons for the lesser presence of ocular dryness compared to monthly-replacement lenses.

A review of meibomian gland structure, function, and contact lens wear

PURPOSE

To provide a balanced literature review of the studies that have evaluated the effect of contact lenses on meibomian gland (MG) health.

METHODS

A PubMed.gov literature search was conducted on or before May 15, 2021. No other time constraints were applied. Search terms included the following: "meibomian gland(s)" plus "contact lens(es)" or "meibography" plus "contact lens(es)". Only full text articles written in English were considered. The reference lists of recovered papers were used to identify articles missed during the primary search. Included articles were required to discuss the impact of contact lenses on MG morphology or function and were graded according to the level of evidence presented.

RESULTS

The literature indicates that contact lenses impact MG function; however, the data are equivocal regarding contact lenses inducing MG structural changes. The literature likewise indicates that the mechanism(s) by which contact lenses impact the MGs are likely multifactorial. Recent data suggests that MGs may have some plasticity. Detected differences between studies likely stem from varied populations evaluated, study designs, and the duration of the evaluation periods.

CONCLUSIONS

With this literature review finding conflicting relationships between MG health and contact lens use, future longitudinal studies with standardized clinical MG assessments are needed to determine the true impact of contact lenses on MG health. Until these data are obtained, contact lens wearers should undergo a full MG evaluation, especially because recent data suggest that MG treatments may restore MG structure and function.

All soft contact lenses are not created equal

Soft contact lenses that have been prescribed by eye care practitioners are sometimes substituted for alternative lenses by unqualified, unregulated and sometimes even fully regulated lens suppliers, in the mistaken belief that there is essentially no difference between different soft lens types. This review considers the implications of inappropriately substituting soft contact lens types in terms of (a) lens properties: surface treatment, internal wetting agents, material, total diameter, back optic zone radius, thickness, edge profile, back surface design, optical design, power, colour (tint) and ultraviolet protection; and (b) lens usage: wearing modality (daily versus overnight wear) and replacement frequency. Potential aspects of patient dissatisfaction and adverse events when prescribed soft lenses are substituted for lenses with different properties or intended usage are considered. Substitution of 15 of the 16 lens properties considered (i.e. except for back surface design) was found to be related to at least one - and as many as six - potential sources of patient dissatisfaction and adverse ocular events. Contact lens are medical devices which are prescribed and fitted; they should never be substituted for another lens type in the absence of a new prescription further to a full finalised fitting, for the simple reason that all soft contact lenses are not created equal. A substituted lens may have properties that results in undesirable consequences in respect of vision, ocular health, comfort and cosmetic appearance, and may be incompatible with the lifestyle of the patient.

A Review of Contact Lens Dropout

PURPOSE

Contact lens (CL) dropout is likely a major factor contributing to the near stagnant growth in the CL market. The purpose of this review is to summarize the current state of knowledge related to the frequency of CL dropout and the factors associated with it.

METHODS

PubMed.gov was searched on or before March 22, 2020, with the terms "contact lens" with "dropout" or "cessation" or "disruption" or "discomfort". Pertinent articles were collected. The references from these articles were likewise searched to identify additional relevant articles. Only manuscripts written in English were included. No study design or date exclusions were imposed on this review.

RESULTS

This literature review found that CL dropout was frequent across developed countries, with a CL dropout frequency that ranged between 12.0% and 27.4% (pooled mean = 21.7%). The top cited reason for CL dropout in established CL wearers was discomfort, while vision was the top reason in neophyte CL wearers. If given the chance, CL dropouts are often able to successfully resume CL wear up to 74% of the time. While the literature is mixed with regard to factors promoting CL dropout, meibomian gland dysfunction appears to promote CL dropout.

CONCLUSION

CL dropout is a frequently encountered condition that may be curtailed by early detection, patient education, alterative CL options, or early treatment of underlying ocular surface diseases such as meibomian gland dysfunction.

Interfacial polymerization of a thin film on contact lenses for improving lubricity

HYPOTHESIS

A large number of contact lens wearers drop out each year due to end of day discomfort, which could possibly be reduced by designing lenses with highly lubricious surfaces. We hypothesize that polymerizing a thin film of dimethyl acrylamide (DMA) on the surface of the lenses will improve lubricity.

EXPERIMENTS

The thin film is polymerized by loading a commercial contact lens (1-DAY ACUVUE® TruEye®) with N,N,N',N'-Tetramethylethane-1,2-diamine (TEMED) and soaking it in a solution of DMA and ammonium per sulfate (APS). The two components of the redox couple (APS and TEMED) mix near the surface of the lens due to diffusion and react rapidly to form free radicals. The free radicals lead the polymerization of the DMA monomer near the surface resulting in the formation of the thin hydrogel layer that is attached to the lens matrix through activation of unreacted vinyl groups or possibly through formation of entanglements with the lens polymer.

FINDINGS

The thickness of the layer is controlled by the polymerization time which is limited to 30 s to create a layer of DMA only at the surface. The presence of the DMA layer is confirmed through measurements of Fourier-transform infrared spectroscopy (FTIR) spectra in total internal reflection mode. The layer is determined to be about 3-5 µm thick with a water content of about 285%. The presence of the layer significantly improves lubricity as is evident through the qualitative rubbing test and quantitative measurement of the friction coefficient. A preliminary one-week safety study in rabbits show that lens wear does not cause any toxicity.

Evaluation of tear film and the morphological changes of meibomian glands in young Asian soft contact lens wearers and non-wearers

Background

The aim of this study was to explore the differences in terms of tear film and meibomian glands (MGs) between young Asian soft contact lens (CL) wearers and non-wearers.

Methods

A prospective, cross-sectional observational study was conducted using 148 subjects (63 non-wearers, and 85 soft CL wearers who had been wearing CLs for more than 1 year) recruited from a clinic in Tianjin, China. All subjects first responded to an Ocular Surface Disease Index (OSDI) questionnaire and then underwent a standardized dry eye examination, which included measuring tear meniscus height (TMH), non-invasive tear breakup time (NIBUT), and corneal fluorescein staining (CFS). The MGs were evaluated via ImageJ, distorted MG count and the MG dropout were recorded.

Results

Compared to the control group (non-wearers), the CL group recorded higher OSDI and CFS scores, lower TMH and NITBUT values, a larger distorted MG count, and larger MG dropout (all P < 0.05). Pearson correlation analysis found a correlation between MG dropout and the duration of CL use (r = 0.440, P < 0.001), OSDI (r = 0.298, P = 0.006), and CFS scores (r = 0.442, P < 0.001).

Conclusion

CL wearers showed higher MG dropout and reduced TMH and NITBUT, which likely contributes to severe CL-related dry eye symptoms. CL use may lead to a higher MG dropout rate, and the extent of the MG dropout presumably influences the tear film status in CL wearers.

Dry eye symptoms and signs in children wearing OK lenses for six months in China

BACKGROUND

This study aims to investigate symptoms of dry eye and signs of ocular surface disease in children with myopia during OK lens wear.

METHODS

A total of 68 subjects were prospectively managed with OK lens correction. These subjects were 8-14 years of age with myopia -0.50 to -5.00 dioptres of sphere and astigmatism of≤1.00 dioptres of cylinder. Patients with any ocular disease were ruled out from this study. All subjects completed a dry eye symptom questionnaire for OSDI scoring, corneal fluorescein staining, tear film break up time (TBUT) test and Schirmer's test I during the follow-up period. The follow-up period includes the primary visit (baseline), and at one day, one week, one month and six months after wearing the lens.

RESULTS

In terms of dry eye symptoms, we found that OSDI scores were significantly high after one day of wearing the lens (P<0.05). Additionally, TBUT values significantly decreased after one day (P<0.01) and one week (P<0.05) of wearing the OK lens. Corneal staining grade also significantly increased after one day and one week of wearing the OK lens. Furthermore, Schirmer's Test I values slightly, but not significantly, increased after one day and one week of wearing the lens. All variables returned to pre-wear levels at one month after wearing the lens, which remained stable up to six months of wearing the OK lens.

CONCLUSION

Our study is the first reveal that OK lens wear in children leads to dry eye symptoms and disturbs the tear film during the initial period of OK lens wear. However, this did not significantly interfere with tear secretion during the follow-up period.