Ocular complications associated with the use of cosmetic contact lenses from unlicensed vendors

Impact of contact lens hygiene risk factors on the prevalence of contact lens-related keratitis in Alexandria-Egypt

BACKGROUND

This study aimed at measuring the effect of contact lens hygiene risk factors on the prevalence of contact lens-related keratitis and identifying the specific risk factors to both microbial and non-microbial keratitis independently.

METHODS

A cross-sectional study was conducted at Alexandria Ophthalmology Hospital from May to October 2023. All contact lens wearers attending the outpatient clinic had undergone face-to-face interviews using a standardized validated questionnaire which included demographic data and contact lenses (CLs) hygiene risk factors. Participants were classified into two groups; normal group and keratitis group. Keratitis group was further subdivided into non-microbial and microbial group.

RESULTS

The study included 245 contact lens wearers; 149 normal cases, 50 (20.4%) contact lens-related non-microbial keratitis (CLNK) cases, and 46 (18.8%) contact lens-related microbial keratitis (CLMK) cases. Sharing contact lenses and eye trauma were significant risk factors for both CLNK (p=0.036), (p=0.001) and CLMK (p=0.003), (p=0.017). CLs wear duration for more than 12 hours was associated with an increased risk of CLNK by about 4 times (p=0.030) and overnight wear of contact lenses increased the risk of CLNK by 2.6 times (p=0.030). Showering or swimming in lenses was identified as a significant risk factor for CLMK (p=0.012), moreover washing lenses with tap water increased the risk of CLMK (p=0.030).

CONCLUSIONS

Poor compliance with contact lenses hygiene rules results in a high prevalence of contact lens-related keratitis. Eye trauma and sharing contact lenses were significant hygiene risk factors for both contact lens-related non-microbial keratitis and contact lens-related microbial keratitis.

Cosmetic Contact Lenses in the United Kingdom: Assessment of Online Regulation and Quality of Consumer Health Information

OBJECTIVES

To determine the compliance of online vendors to the UK Opticians Act 1989 Section 27 requirements and safety regulations for cosmetic contact lens (CCL) sales and the quality of online CCL health information.

METHODS

The top 50 websites selling CCLs on each three search engines, namely Google, Yahoo, and Bing, were selected. Duplicates were removed, and the remaining websites were systematically analyzed in February 2023. UK legal authorization for CCL sales was assessed using the Opticians Act Section 27 and safety regulations determined by the presence of Conformité Européene (CE) marking. The quality and reliability of online information was graded using the DISCERN (16-80) and JAMA (0-4) scores by two independent reviewers.

RESULTS

Forty-seven eligible websites were analyzed. Only six (12.7%) met the UK legal authorization for CCL sales. Forty-nine different brands of CCLs were sold on these websites, of which 13 (26.5%) had no CE marking. The mean DISCERN and JAMA benchmark scores were 26 ± 12.2 and 1.3 ± 0.6, respectively (intraclass correlation scores: 0.99 for both).

CONCLUSIONS

A significant number of websites provide consumers with easy, unsafe, and unregulated access to CCLs. Most online stores do not meet the requirements set out in the Opticians Act for CCL sales in the United Kingdom. A significant number of CCLs lack CE marking, while the average quality of information on websites selling CCLs is poor. Together, these pose a risk to consumers purchasing CCLs from unregulated websites, and therefore, further stringent regulations on the online sales of these products are needed.

Gone Viral: A Cross-Sectional Analysis of Contact Lens-Related Videos on TikTok

OBJECTIVES

To evaluate the content, sources, and quality of contact lens (CL)-related videos on TikTok, the fastest growing social media platform worldwide.

METHODS

TikTok was queried on October 25, 2021 for the top 200 posts with the hashtag "#contactlenses." Posts meeting inclusion criteria were characterized and assessed for quality with DISCERN, a validated scoring instrument for the appraisal of consumer health information (score range 1-5 with a higher score indicating a higher quality video).

RESULTS

The included 113 posts showed a mean quality of 1.94±0.44. Content included product displays (42%), patient experiences (23%), educational (22%), and comedy (12%). Most product displays featured decorative lenses (98%). Although videos by eye-care providers (ECPs) accounted for most educational content (52%) and showed significantly higher mean quality compared with posts by non-ECPs (2.57±0.18 vs. 1.85±0.13, P <0.001), they were a minority (12%) and showed poor overall quality. Contact lens representation was greatly skewed toward decorative lenses (74%), whereas only 3.5% of videos promoted seeing an ECP.

CONCLUSIONS

Poor quality and skewed representation of posts indicate that CL-related information on TikTok has serious shortcomings. These findings are particularly concerning given that most TikTok users are adolescents and young adults, the same population who tend to be decorative lens wearers and who are at increased risk of CL-related complications. Eye-care providers, professional organizations, and regulatory agencies should be urged to increase their engagement with the platform, especially regarding educational content creation and CL marketing oversight.

A Review of Contact Lens-Related Risk Factors and Complications

The purpose of this article is to develop a modern strategy for handling difficulties related to contact lenses and their care. A growing number of people throughout the world are currently concerned by eye-related undesirable activities in allergy sufferers and those wearing contact lenses. While many wearers who experience ocular discomfort exhibit dryness as a symptom, many other contact lens-related pain symptoms also include irritation and fatigue, and managing coexisting diseases must be done in accordance with aspects of wearing contact lenses, all of which undoubtedly increase discomfort.

It is typical for contact lens storage containers to have persistent microbial contamination, which has been linked to microbial keratitis (MK) and clear corneal invasion. Contact lens-associated MK is an interesting, potentially sight-threatening complexity arising from wearing soft contact lenses. Estimates show that for every 10,000 persons who wear contact lenses each year, there are 2 to 5 occurrences of MK. Investigating separate determinants for contact lens-associated MK and evaluating their impact on infection load is one of the challenges in their administration. It is hoped that this will offer a useful outline of the complicated issues of contact lens wear that are both infectious and non-infectious. Recent epidemiological studies detailing the risk factors associated with contact lens use, and the effect of pathogen and individual immune profiles on the severity of diseases have enlightened how we might interpret the prophylaxis and prevention of contact lens-related corneal infection. The most dreaded side effect of contact lens use, infectious keratitis linked with contact lenses, will be reviewed, along with the most recent advancements in its diagnosis and treatment.

Cosmetic Contact Lens-Related Corneal Infections in Asia

PURPOSE

To explore demographics, disease characteristics, and wear habits in cosmetic contact lens (CL)-related corneal infections in Asia.

DESIGN

Prospective multicenter cross-sectional study.

METHODS

Cases of CL-related corneal infection presenting over a 12-month period were prospectively identified from 11 centers in 8 countries in Asia. Case demographics, clinical features, microbiology, and compliance characteristics were compared between wearers using CLs for cosmetic purposes and those using CLs for the correction of refractive errors.

RESULTS

Six hundred and ninety-four CL wearers with corneal infection presented: 204 cosmetic CL (29.4%) and 490 (70.6%) refractive CL wearers. Cosmetic CL infections comprised 7%-54% of cases across the region. Compared with noncosmetic CL wearers, cosmetic CLs wearers were significantly more likely to be female (90% vs 59%), young (aged <25, 68% vs 44%), and to have a shorter period of wear experience. Lenses worn by cosmetic CL wearers were more likely to be hydrogel materials and manufactured with the pigment located on the back surface of the CL. Presenting disease characteristics and visual outcomes were similar in both groups. Causative organisms were similar between the 2 groups; however, there was a higher rate of Acanthamoeba disease (9%) in cosmetic wearers, compared with refractive wearers (1%; P < .005).

CONCLUSIONS

Cosmetic CL infections represent a significant proportion of CL-related infections in Asia. Cosmetic CL users with corneal infections are generally young, female, and wearing hydrogel CLs. Internet supply, quality control, and regulation of the sale of these products provide significant challenges in managing this population of vulnerable wearers.

A web-based survey of contact lens-related adverse events among the Japanese female population

To assess the safety of cosmetic contact lenses and to identify other factors of contact lens (CL)-related complications for Japanese females. A web-based, cross-sectional, observational survey of complications related to CL use was performed. The frequencies of complications were compared between transparent and cosmetic CLs. Besides lens pigmentation, age, replacement schedule, total experience, daily wear time, location of purchase, stacking of CLs, CL exchange with friends, compliance to hygiene procedure, replacement of CLs at intervals longer than recommended, and CL wear overnight were considered as risk factors. Logistic regression analyses were performed to calculate the odds ratios. A total of 3803 Japanese females were analyzed. The frequency of adverse events was 33.4% (95%CI 31.3-35.4%) and 35.7% (95%CI 33.5-38.0%) for transparent and cosmetic CLs, respectively. In a multivariate model, statistically significant factors associated with complications included the following: quarterly schedule lenses, replacement at intervals longer than recommended, compliance to hygiene procedure, overnight wearing, purchase at physical shops and on the internet, and longer daily wearing time. Most of the risk-increasing behaviors are preventable. The role of public health ophthalmology is to increase awareness and to improve CL use behaviors.

Photoablative cosmetic iridoplasty: effective, safe, and predictable-eye color change in 1176 eyes

Purpose

To evaluate photoablative cosmetic iridoplasty (PCI), and its efficacy, safety, predictability, and satisfaction with the 532 nm Crystal Q-switched Nd: Yag laser, with 3–4 ns pulses, for depigmentation of the anterior epithelium of the iris in cases of heterochromia, nevus, or cosmetic indications (eye color change).

Design

Prospective clinical study on efficacy, safety, predictability, and satisfaction.

Method

The selection of patients was carried out in healthy individuals, over 18 years of age, with iris heterochromia (congenital-7% or acquired, secondary to topical medication-1%, trauma-0.5% or surgery-0.25%), nevus-0.25% and cosmetic cases-91%. Data were collected independently by assistant optometrists and classified in database. Excel statistical program was used to perform a general descriptive study, calculation of correlation factors, and statistical significance analysis between quantitative variables (Student T Test). PCI was performed in 1176 eyes of 588 patients. The procedures were planned in 2–3 phases of 4 consecutive sessions spaced 4–6 months apart. The IRÎZ^® (Eyecos^®) scanner was used to evaluate the cases, with photography, optical coherence tomography, and pneumotonography modules, along with the following software programs: Predictor^®, Simulator^® 3D, Analyzer^® and Planner^® (Eyecos^®).

Results

This study began in 2012, so far 9 years of follow-up, to compare and choose the most suitable among 4 types of lasers to perform cosmetic iridoplasty. Finally, after 5 years, the Crystal Q-switched Nd: Yag at double frequency (532 nm) with 3–4 ns pulses demonstrated the highest efficacy, safety and predictability, so since early 2017 only this equipment has been used. Significant differences were found after 5-year follow-up between 1064, 532, 577 and 532/3–4 ns p = 0.09172, 0.06377 and 0.10183. From 9 January 2017 to 28 February 2020, 1176 eyes have been treated in 588 patients, with a mean age of 33.7 years (SD = 9.68 years, range = 18–70 years). 46.2% were male, and 53.7% were female. The efficacy, as quantified with the Analyzer^® comparison software, was nearly 87–95%. There were no significant differences in corrected vision (9 years total follow-up p = 0.78235; last 4 years FU p = 0.99999) and ocular pressure (9 years total FU p = 0.68251; last 4 years FU p = 0.63204) before and after the procedure. The only notable complications (25%) were delayed and brief iritis, which were self-limited with routine topical treatment. The predictability was 80–90%. In the lightest-colored eyes, turquoise blue colors were obtained as a rule, in varying brightness; and in the darkest ones, gray blue tones of varying lightness. The patients’ subjective satisfaction at the end of treatment was 95%.

Conclusion

After 9 years of uninterrupted follow-up, PCI has demonstrated a high effectiveness to selectively depigment superficial melanin of iris, with a high predictability and patient satisfaction, without remarkable long-term complications. Only for a week, appropriate pre- and postoperative medication was necessary to guarantee the absence of discomfort, thus confirming security. PCI is effective, safe, and predictable for the treatment of pigmentary disorders in the iris and for the elective cosmetic indications in eye color change.

Passive Verification: A Flawed System Putting Patients' Sight at Risk

OBJECTIVE

To assess the rate of erroneous or expired (invalid) contact lens prescriptions submitted for passive verification at two practice sites in Cleveland, OH.

METHODS

Passive verification facsimile (FAX) requests were collected from office staff at a county hospital (MetroHealth [MH]), and at a private ophthalmology group office (University Ophthalmology Associates [UOA]) in Cleveland, Ohio, from January 2013 to January 2018.

RESULTS

A total of 415 verification requests were evaluated (339 MH, 75 UOA), 28.2% (104 MH, 13 UOA) were expired, 11.8% (48 MH, one UOA) were not under the care of the doctor to whom the request was directed, 8.9% (32 MH, 5 UOA) were incorrect, and 3.9% (16 MH, 0 UOA) did not complete fitting. The total rate of invalid prescriptions was 52.8% (200 MH, 19 UOA).

CONCLUSIONS

There is a high rate of invalid prescriptions presented for passive verification. Although the majority of prescriptions are simply expired, there is a fraction of prescriptions that contain incorrect specification of lens parameters or no record of prescription by that doctor. The current mechanism of passive verification, with the burden on the provider for denial within a short time window, makes it likely that such prescriptions would be filled, potentially putting patient comfort and safety at risk.

Novel Polyvinyl Pyrrolidone-Loaded Olopatadine HCl-Laden Doughnut Contact Lens to Treat Allergic Conjunctivitis

Olopatadine HCl is an antiallergic drug used for the management of allergic conjunctivitis. Currently, it is delivered via eye drop solution, which is highly inefficient due to low bioavailability. Silicone contact lenses can be used to sustain the release of ophthalmic drugs. However, the presence of drug alters the optical transmittance and physical properties of the contact lens. The objective was to design a novel polyvinyl pyrrolidone (PVP)-coated olopatadine-ethyl cellulose microparticles-laden doughnut contact lens to sustained ocular delivery with limited alteration to the optical and swelling properties of the contact lens. The doughnut was implanted within the periphery of the lens using modified casting technique. Olopatadine HCl was loaded by soaking (SM-OL), direct loading (DL-OL), and doughnut casting method (DNT-OL). PVP (comfort agent) was loaded on the surface of contact lens for all the batches via novel curing technique. The in vitro olopatadine HCl release data of SM-OL (up to 48-72 h) and DL-OL batches (up to 72 h) showed high burst release, whereas DNT-OL batch showed sustained release up to 120 h without significant (p > 0.05) alteration in the optical and swelling properties of contact lens. All the batches showed sustained release of PVP up to 120 h. The in vivo studies in the rabbit tear fluid showed improvement in the olopatadine HCl and PVP retention time in comparison to eye drop solution. The PVP-loaded DNT-OL-500 lens showed tear stabilization (comfort wear) in Schirmer strip test (rabbits) with no protein adherence in comparison to DNT-OL-500 lens without PVP. The study demonstrated the successful delivery of olopatadine HCl and PVP-K30 from the doughnut contact lens for the extended period with limited alteration to the optical and swelling properties of contact lens.

ToF-SIMS and AFM Characterization of Brown Cosmetic Contact Lenses: From Structural Analysis to the Identification of Pigments

Over the years, soft contact lenses for vision correction and cosmetic and therapeutic purposes have been greatly improved. For cosmetic contact lenses, the pigments need to be nontoxic, and the position of the pigment layer is particularly important because of the risks posed by pigment elution and the roughness of the lens surface. In this paper, we characterized the properties of brown cosmetic contact lenses made by three different manufacturers using surface analytical techniques. The surface topographies of the noncolored and colored parts were obtained by atomic force microscopy (AFM), and the position and composition of the pigment layer were determined by analyzing the cross section of the contact lenses using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). The influence of pigment location on surface roughness was also examined. In addition, to find the method of the evaluation for the risk of surface elution of the pigments in the colored parts, the mass spectra and ion images of the surfaces were obtained by time-of-flight secondary ion mass spectrometry (ToF-SIMS) with a new sample preparation. From the ToF-SIMS spectra, we observed specific fragment ions of the poly(hydroxyethyl methacrylate) (PHEMA) polymer and found differences in the composition of the pigment layer depending on the manufacturers. The cross-sectioned image and 3D chemical characterizations of metallic and specific ions in the brown cosmetic contact lenses clearly indicated the spatial distribution and location of the pigment layer that can be used for the evaluation of pigment elution.

Identifying Pigment Enclosure in Cosmetic Contact Lenses

Supplemental Digital Content is Available in the Text.

The presence of surface pigment in cosmetic contact lenses may influence possible ocular health issues and contact lens discomfort. Two in vitro test methods were developed to investigate whether a variety of cosmetic contact lenses are manufactured with a visible clear layer, indicating that the pigment bulk is enclosed within the lens matrix.

Use and misuse of cosmetic contact lenses among US adolescents in Southeast Texas

Background

Cosmetic contact lenses (CCL) are popular among adolescents, but incorrect use can harm the eye.

Methods

This study assessed CCL hygiene behaviors among adolescents attending a Texas pediatric clinic. Anonymous surveys about CCL hygiene practices were administered to adolescents 13–18 years old.

Results

We found that 14% (53/392) of respondents had worn CCL, of which 83% were females. Over 70% reported first use at <15 years old. Knowledge about CCL was low and two-thirds of users had not been instructed on proper care. More than half stored them in water and did not rinse them with contact solution after removal. Over one-third wore CCL >8 hours/day. Moreover, 15% of CCL users reported borrowing someone else’s CCL. Complications resulting from wearing CCL were common.

Conclusion

This study highlights poor CCL hygiene among adolescents. These data demonstrate the need to develop interventions to educate adolescents on proper care and risks associated with CCLs.

Review of Contact Lens-Related Complications

The purpose of this article is to provide a review of existing literature describing complications with contemporary contact lenses and their management. It is envisioned that this will serve as a useful summary of noninfectious and infectious complications associated with contact lens wear.

Evaluation of Pigment Distribution and Depth Analysis Methods for Decorative Soft Contact Lenses

OBJECTIVES

This study evaluates pigment component distribution and depth in decorative soft contact lenses (DSCLs) using a variety of analytical methods.

METHODS

We sampled 18 DSCLs using optical microscopy, optical coherence tomography analysis, Z-stack analysis, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX), and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to evaluate the distribution and depth of pigment components.

RESULTS

Pigment distribution in DSCLs was easily observed with optical methods including Z-stack analysis. X-ray photoelectron spectroscopy, SEM/EDX, and TOF-SIMS were used to evaluate the level of pigment exposure on the lens surface and the results showed significant differences between the methods. Pigment components were detected in 16 samples by SEM/EDX, but not by XPS. Pigment components were only detected in eight samples using TOF-SIMS.

CONCLUSIONS

It may be necessary to show that a nanometer-thick monomolecular film does not exist on the surface of DSCLs, to demonstrate the exposure of a pigment particle. Taking into account the principle behind each of the measurement methods and the resolution and sensitivity of each of the analytical methods compared, TOF-SIMS may be the most appropriate method to accurately judge pigment exposure on DSCLs. The Z-stack method may be useful for estimating the depth of pigment components in DSCLs.

A review of cosmetic contact lens infections

This paper provides a comprehensive review of the existing literature surrounding cosmetic contact lens infections. In this paper, lens-related, dispensing-related and patient-related factors are examined in detail.

Materials and Applications of Smart Diagnostic Contact Lens Systems

Contact lenses were originally developed for the purpose of vision correction, but they have recently been used for various purposes. Because contact lenses are minimally invasive, they are used in diagnostic and drug delivery applications. In particular, interest in using contact lenses for the purpose of diagnosing diseases by fusing contact lenses with information technology (IT), nanotechnology (NT), and biotechnology (BT) is increasing. These contact lens-based platforms are getting more attention as Google and Novartis develop contact lenses for diabetes diagnosis. Therefore, this chapter introduces materials that can be used for contact lens materials and diagnostic contact lenses, and discusses future prospects.

The use of contact lenses among university students in Chengdu: Knowledge and practice of contact lens wearers

PURPOSE

To assess the prevalence and general knowledge of contact lens wearers among college students in Chengdu, a metroplolitan of Chinaand find out the routine habits of use and hygienic conditions when wearing contact lenses.

METHOD

The questionnaire was distributed to 1,600 ametropic participants who were from 8 different universities. Data about demographics, general contact lens handling habits, personal attitudes, hygiene behaviors and eye health conditions were collected. We made the analysis ofthe demographics and wearing of contact lenses. Possible reasons for behaviors related to the care of contact lenses were analyzed.

RESULTS

The prevalence of contact lens use was 19.80%. Most users (82.15%) were females. An aesthetic effect was cited as the first reason for using (57.91%). The comfort of eyes was the first consideration (75.76%) when buying. To keep clean and use safe, 86.20% subjects washed hands before handling and 83.50% cleaned the lens carefully after removing. There was significant difference between males and females regarding the replacement of the solution (p=0.014). 32.66% wears knew the removal of protein deposits. A total of 54.88% were not informed of the potential complications of contact lens. The incidence of ocular discomfort was 44.78%. Only 3.03% of the students paid regular visits to ophthalmic clinics.

CONCLUSION

The prevalence of contact lenses was relatively low in Chengdu. The wears had limited knowledge about using and careof contact lens. More education on standard lens wear and care should be provided to wearers.

The diagnosis and management of contact lens-related microbial keratitis

Contact lens-associated microbial keratitis poses a diagnostic dilemma for optometrists on two fronts. The distinction between sterile inflammation and microbial infection is often blurred. In addition, there is a requirement with nearly 50 per cent of the Australian and New Zealand optometric profession being therapeutically endorsed, to distinguish between cases of infection that can be managed in the community verses those that require escalation to public hospitals that have access to laboratory diagnostic tools and advanced imaging techniques, such as in vivo confocal microscopy. Pattern recognition and incorporation of knowledge of aetiology and risk factors assists optometrists to decide on optimal management strategies. Skilled optometrists will utilise emerging diagnostic and therapeutic technologies to ensure safe management strategies and better outcomes for these cases.

Risk Factors for Contact Lens-Related Microbial Keratitis: A Case-Control Multicenter Study

PURPOSE

The most feared complication of contact lens (CL) wear is microbial keratitis (MK), even though its incidence remains low. This study aimed to identify the risk factors of CL-related MK in a large, prospective, multicenter case-control study.

METHODS

A multicenter case-control study was designed. The CL-related MK subpopulation (Case) was compared with healthy CL wearers (Control) using a 52-item anonymous questionnaire designed to determine subject demographics and lens wear history. Univariate and multivariate logistic regression analyses were performed to compare both groups.

RESULTS

The study enrolled 499 cases and 508 controls. The risk factors associated with the greatest increased odds of CL-related MK were as follows: using disinfecting solution more than 3 months (odds ratio [OR]=1.94), cosmetic CL wear and use of multipurpose disinfection solution (1.37 each), overnight wear, and soft lens use (OR=1.24 each). The protective factors associated with the greatest reduction in OR were fitting by an ophthalmologist (OR=0.73) and hyperopia versus myopia (OR=0.75).

CONCLUSIONS

The infectious determinants were linked to the type of lenses, hygiene routine, CL handling, disinfecting solution, and storage case. This study aimed to highlight the increasingly CL-related MK, which likely occurs because of lack of patient information regarding basic rules of hygiene and CL care and handling.

Scanning Electron Microscopy Findings With Energy-Dispersive X-ray Investigations of Cosmetically Tinted Contact Lenses

To investigate the surfaces and principal elements of the colorants of cosmetically tinted contact lenses (Cos-CLs).

Effect of the pigment-free optical zone diameter of decorative tinted soft contact lenses on visual function

AIMS

We investigated changes in visual function after wearing decorative tinted soft contact lenses with different pigment-free optical zone diameters.

METHODS

A prospective study was performed in 30 eyes of 30 healthy volunteers. Best-corrected visual acuity (BCVA), ocular higher-order aberrations (HOAs), modulation transfer function (MTF), Strehl ratio and contrast sensitivity were evaluated after wearing clear lens and tinted lenses with different pigment-free optical zone diameters (4, 5 and 6 mm).

RESULTS

BCVA decreased from 0.00 logMAR after wearing a clear lens to 0.04±0.04 logMAR after wearing 4 mm optical zone lens (p<0.001). As the optical zone diameter decreased, ocular aberrations were induced. Total HOAs, coma aberration and secondary astigmatism showed significant difference between clear lens and 5 or 4 mm optical zone lenses (p<0.050). Spherical aberration and trefoil showed significant difference between clear lens and 4 mm optical zone lens (p<0.050). The results for Strehl ratio revealed poorer optical quality for both 5 and 4 mm optical zone lens (both p=0.002). The entire ocular MTF was significantly different, corresponding to the decreased optical zone diameter. The HOAs showed a correlation with the blocked pupil covered by the tinted part (r=0.435, p<0.001). In photopic and mesopic conditions, the contrast sensitivity decreased significantly with the reduced pigment-free optical zone diameters.

CONCLUSION

Decorative tinted contact lenses significantly increased ocular aberrations and decreased optical quality and contrast sensitivity, as the pigment-free optical zone diameter decreased. Therefore, consumers of tinted lenses should be informed about the possible disturbance in visual function.

TRIAL REGISTRATION NUMBER

NCT02537275.

Review of complications associated with contact lenses from unregulated sources of supply

OBJECTIVE

To review existing studies and case reports regarding complications associated with contact lenses (CLs) from unregulated sources of supply and to identify any relevant trends.

METHODS

A systematic literature search was performed to locate publications concerning complications associated with CLs obtained from unregulated sources of supply.

RESULTS

A total of 23 articles were identified that represent 70 individual cases. All 8 of the pre-2006 case reports originated from the United States and the United Kingdom, whereas from 2006 onwards, only 2 of the 15 reports came from these locations. Over-the-counter supply accounted for 73% (51/70) of cases, whereas 17% (12/70) were borrowed or shared lenses and 6% (4/70) lenses were obtained through the Internet. Nearly, three quarters of patients (30/42, 71%) waited longer than 48 hours after the onset of symptoms before seeking medical attention; 10 patients waited longer than a week, and 5 longer than a month. Microbial keratitis (MK) was reported in 43 (61%) patients, with permanent damage occurring in 72% (31/43) of patients followed to conclusion. Known risk factors associated for MK were present in all cases irrespective of whether the patients developed MK.

CONCLUSIONS

There are various reasons to presume that the unregulated supply of CLs might result in the use of inappropriate lenses, increase the risk of poorer lens hygiene, and militate against the prompt treatment of any consequent complications. There is some indication that the introduction of regulations to control the supply of plano CLs has alleviated the level of complications.

Atomic force microscopy and scanning electron microscopy analysis of daily disposable limbal ring contact lenses

BACKGROUND

Limbal ring (also known as 'circle') contact lenses are becoming increasingly popular, especially in Asian markets because of their eye-enhancing effects. The pigment particles that give the eye-enhancing effects of these lenses can be found on the front or back surface of the contact lens or 'enclosed' within the lens matrix. The purpose of this research was to evaluate the pigment location and surface roughness of seven types of 'circle' contact lenses.

METHODS

Scanning electron microscopic (SEM) analysis was performed using a variable pressure Hitachi S3400N instrument to discern the placement of lens pigments. Atomic force microscopy (Dimension Icon AFM from Bruker Nano) was used to determine the surface roughness of the pigmented regions of the contact lenses. Atomic force microscopic analysis was performed in fluid phase under contact mode using a Sharp Nitride Lever probe (SNL-10) with a spring constant of 0.06 N/m. Root mean square (RMS) roughness values were analysed using a generalised linear mixed model with a log-normal distribution. Least square means and their corresponding 95% confidence intervals were estimated for each brand, location and pigment combination.

RESULTS

SEM cross-sectional images at 500× and 2,000× magnification showed pigment on the surface of six of the seven lens types tested. The mean depth of pigment for 1-DAY ACUVUE DEFINE (1DAD) lenses was 8.1 μm below the surface of the lens, while the remaining lens types tested had pigment particles on the front or back surface. Results of the atomic force microscopic analysis indicated that 1DAD lenses had significantly lower root mean square roughness values in the pigmented area of the lens than the other lens types tested.

CONCLUSIONS

SEM and AFM analysis revealed pigment on the surface of the lens for all types tested with the exception of 1DAD. Further research is required to determine if the difference in pigment location influences on-eye performance.

Microbial adherence to cosmetic contact lenses

AIM

To investigate whether cosmetic contact lenses (CCL) with surface pigments affect microbial adherence.

METHOD

Fifteen brands of CCL were purchased from optical, non-optical retail outlets, and via the Internet. A standardized rub-off test was performed on each CCL (five lenses per brand) to confirm the location of the pigments. The rub-off test comprised gentle rubbing on the surfaces of each CCL with wetted cotton buds for a maximum of 20 rubs per surface. A new set of CCL (five lenses per brand) were incubated in Pseudomonas aeruginosa overnight. Viable counts of adhered bacteria were determined by the number of colony-forming units (CFU) on agar media on each lens. The adherence of P. aeruginosa as well as Staphylococcus aureus and Serratia marcescens to three brands of CCL (A-C) (five lenses per brand) were also compared to their adherences on their clear counterparts.

RESULTS

Only two of the 15 brands of CCL tested (brands B and C) had pigments that did not detach with the rub-off test. The remaining 13 brands of CCL all failed the rub-off test and these lenses showed higher P. aeruginosa adherence (8.7 × 10(5)-1.9 × 10(6) CFU/lens). Brands B and C lenses showed at least six times less bacterial adhesion than the other 13 brands. Compared to their clear counterparts, bacterial adherence to brands B and C lenses did not differ significantly, whereas brand A lenses showed significantly higher adherence.

CONCLUSION

Surface pigments on CCL resulted in significantly higher bacterial adherence.

A meta-analysis of studies on cosmetically tinted soft contact lenses

BACKGROUND

Concerns regarding the safety of cosmetically tinted contact lenses have been reported in the literature. The purpose of this paper is to evaluate the safety of cosmetically tinted contact lenses in a large number of patients across six clinical trials that varied from 1 week to 3 months in duration.

METHODS

LENSES TESTED INCLUDED: Naturelle limbal ring daily disposable, Lacelle limbal ring daily disposable, Lacelle colored cosmetic daily disposable, Lacelle limbal ring planned replacement at 2 weeks, and Alamode traditional/annual colored cosmetic lens. The primary safety outcome was slit-lamp examination, including epithelial edema, epithelial microcysts, corneal staining, bulbar injection, limbal injection, upper lid tarsal conjunctival abnormalities, corneal neovascularization, and corneal infiltrates. High contrast logMAR visual acuity with lenses, and lens wearing time, movement, and centration, are also presented.

RESULTS

A total of 871 subjects (1,742 eyes) and 23 clinical investigators participated in the six studies, with an average completion rate of 96.4% across all studies. The mean age of the patients was 26.8 ± 6.6 years, and 86.7% of participants were female. The total number of slit-lamp examinations across the six studies was 2,456 visits by eye (1,228 visits by patient). There were no slit-lamp signs > grade 2 for any finding, with the exception of corneal staining in one study. In this study, grade 3 corneal staining was noted in one eye (0.1%) at follow-up visit 1 and four (0.6%) of all eligible dispensed eyes at follow-up visit 2, with no eyes requiring medical treatment. No adverse events were reported during any of the trials.

CONCLUSION

The cosmetically tinted lenses evaluated in this meta-analysis appear to be safe when properly prescribed by an eye care professional and used in a compliant manner.

Colored cosmetic contact lenses: an unsafe trend in the younger generation

PURPOSE

To identify the microbiological profile and evaluate the clinical course and outcomes in patients who developed severe infectious keratitis after colored cosmetic contact lens wear.

METHODS

This case series includes 13 patients who developed severe infectious keratitis after colored cosmetic contact lens wear. A detailed history regarding contact lens availability and storage and handling techniques was taken. All patients underwent standard diagnostic microbiological evaluation followed by culture-guided topical antimicrobial therapy.

RESULTS

Of 13 patients, 8 were male and 5 were female, with mean age at presentation of 19 ± 3.8 years. All patients were emmetropic, and lenses were worn solely for cosmetic purposes. Seven lenses were dispensed without prescription or fitting from an unlicensed optical shop, 5 patients had shared lenses with friends/relatives, and 1 patient obtained the lens from the garbage. None of the patients followed the recommended contact lens handling and storage techniques. The causative microorganisms included Pseudomonas aeruginosa (54%), Staphylococcus aureus (25%), and Staphylococcus epidermidis (17%), with 1 case of viral keratitis. In 62% of cases, ulcer size was ≥5 × 5 mm and posttreatment corrected visual acuity was 6/24 or less. All patients responded well to topical antimicrobials, and none required surgical intervention.

CONCLUSIONS

Over-the-counter use of decorative lenses as a cosmetic aid is rapidly increasing. Easy and unmonitored availability of these cosmetic lenses is followed by severe sight-threatening complications in young emmetropic individuals.

Antibiotic susceptibility patterns of pseudomonas corneal ulcers in contact lens wearers

PURPOSE

To evaluate the resistance or susceptibility of Pseudomonas aeruginosa, the most common pathogen in contact lens keratitis and corneal ulcer, to different antibiotic regimens.

MATERIALS AND METHODS

This cross-sectional study included all patients with recently diagnosed contact lens corneal ulcer whose culture results were positive for P. aeruginosa, from March 2009 to March 2010. The empirical antibiotic therapy was changed to appropriate antibiotics according to the culture results, provided that satisfactory clinical improvement was not achieved with the initial antibiotic regimen. The overall sensitivity or resistance of P. aeruginosa to the most commonly used antibiotics was assessed based on the results of the antibiograms.

RESULTS

Fifty-two patients (43 females and 9 males) were included. Forty-five patients (86%) were wearing cosmetic contact lenses, while 7 patients (14%) were using therapeutic contact lenses. Thirty-nine patients (75%) were hospitalized and13 patients (25%) were followed up through an outpatient clinic. Thirty patients (58%) had central ulcers, whereas 22 patients (42%) had peripheral ulcers. Twelve patients (23%) had hypopyon in their first exam. The mean time to diagnose the ulcer after the last time wearing was 2 days (range: 12 hours to 5 days). AMT was required for 10 patients (19%). Based on the antibiograms, PA was shown to be sensitive in 100% of cases to ceftazidime and ciprofloxacin. Amikacin, imipenem, and gentamicin were the second most effective antibiotics.

CONCLUSION

P. aeruginosa was highly sensitive to ceftazidime, ciprofloxacin, and amikacin. All cases were resistant to cefazolin. Resistance to multiple antibiotics might be a significant concern in patients with corneal ulcers. In referral centers dealing with corneal ulcers, the initial antibiotic regimens should be changed from time to time to prevent this phenomenon.

Microbial keratitis as a foreseeable complication of cosmetic contact lenses: a prospective study

PURPOSE

A recent study shows that the relative risk of contact lenses (CL)-related microbial keratitis (MK) is highly increased with cosmetic contact lenses (CosCL). The aim of our study is to illustrate the implications of the CosCL on the occurence of MK and to describe the subpopulation of CosCL wearers.

METHODS

A prospective multicenter study was conducted in 12 French University Hospitals on all lenses wearers presenting with MK between July 2007 and July 2009, including CosCL wearers. Patients had a complete ophthalmological examination and were interviewed by a 50 items anonymous 'questionnaire' to determine subject demographics and lenses wear history. The CosCL-related MK subpopulation (case) was described and finally compared to (noncosmetic) CL-related MK (control).

RESULTS

Two hundred and fifty-six patients were included for contact lenses-related MK. Thirty-two of them (12.5%) were seen for MK after wearing CosCL. Compared with CL, CosCL wearers are younger (21 versus 27 years of age) and recent wearers (3 versus 9 years). CosCL were rarely dispensed by eye care professionals increasing the risk of MK (OR, 12.3). Education about lens care and handling was deficient for most of CosCL wearers (OR, 26.5). Sixty per cent of CosCL cases versus 13% of CL-related MK had a final visual acuity less than 20/200.

CONCLUSION

Patients who acquire CosCL are less likely to be instructed on appropriate lenses use and basic hygiene rules. Consequently, CosCL wearers are experiencing acute vision-threatening infections.

Pigment deposition of cosmetic contact lenses on the cornea after intense pulsed-light treatment

We report a case of corneal deposition of pigments from cosmetic contact lenses after intense pulsed-light (IPL) therapy. A 30-year-old female visited our outpatient clinic with ocular pain and epiphora in both eyes; these symptoms developed soon after she had undergone facial IPL treatment. She was wearing cosmetic contact lenses throughout the IPL procedure. At presentation, her uncorrected visual acuity was 2/20 in both eyes, and the slit-lamp examination revealed deposition of the color pigment of the cosmetic contact lens onto the corneal epithelium. We scraped the corneal epithelium along with the deposited pigments using a no. 15 blade; seven days after the procedure, the corneal epithelium had healed without any complications. This case highlights the importance of considering the possibility of ocular complications during IPL treatment, particularly in individuals using contact lenses. To prevent ocular damage, IPL procedures should be performed only after removing the lenses and applying eyeshields.

[Infectious keratitis and cosmetic lenses: a five-case retrospective study]

PURPOSE

To determine the characteristics of infectious keratitis related to plano cosmetic lenses.

METHODS

Retrospective case study of a series of infectious keratitis among plano cosmetic lenses wearers. The main parameters were demographic data, medical history, risk factors for infectious complications and keratitis severity criteria, microbiological results, clinical course, and final visual acuity.

RESULTS

Five patients were included, all females, ranging from 15 to 50 years of age. Four were emmetropic. One patient had undergone refractive photokeratectomy a few months before. All had risk factors for infectious complications. The fundamental causes of infections were diverse: bacterial abscesses, keratomycosis, and amoebic keratitis. All presented severity criteria. In two cases, the keratitis led to severe consequences with legal blindness requiring penetrating keratoplasty in one case.

DISCUSSION

Infectious keratitis in plano cosmetic lenses wearers is not rare and may have dramatic consequences. Sales are specifically regulated and the lenses are considered cosmetic products, not medical devices. The sales regulations for plano cosmetic lenses should be updated, as several countries have already done after encountering many serious incidents.