The effect of a compliance enhancement strategy (self‐review) on the level of lens care compliance and contamination of contact lenses and lens care accessories

Effect of text messages designed to change contact lens compliance: A randomised controlled trial

PURPOSE

Contact lens behaviours such as poor hand and lens hygiene are common and are associated with increased risk of microbial keratitis. Evidence for health promotion strategies to address this gap is required. The trial examined the effectiveness of a customised text-messaging intervention on compliance, discontinuation rate and wearer satisfaction in contact lens wearers.

METHODS

The parallel group, double masked, randomised clinical trial was pre-registered with the Australian and New Zealand Clinical Trials Registry (ACTRN12621001719820). Contact lens wearers were recruited using social media and optometry partners in clinical practice. Participants (n = 76) received the intervention and usual care. The control group (n = 75) received usual care. Intervention text messages (range 56-76) were customised, provided education, reminders, and motivation and were delivered over six months. Outcomes were validated self-report online surveys for compliance (0-100), satisfaction (0-100) and discontinuation (Y/N), at 3 months and 6 months. Secondary outcomes were intervention feasibility and acceptability.

RESULTS

Participants mean age was 38 years, 105/151 (70 %) female and 83 % completed the trial (intervention 60/76, control 65/75). The intervention group demonstrated better compliance than control with an adjusted between-group-difference at 3 months of 5.2, 95 % confidence interval (CI), 1.6-8.7, P = 0.004 and at 6 months 3.9, 95 % CI 0.2-7.6, P = 0.04. This difference in compliance is clinically significant, equivalent to a single change in a behaviour such as starting to handwash or ceasing overnight wear. There was no adjusted between-group-difference in satisfaction at 3 months (0.8, 95 % CI -4.3-6.0, P = 0.75) or at 6 months (-0.4, 95 % CI -5.7-4.9, P = 0.89). Few participants (7/151, 4.6 %) discontinued contact lens wear (3 intervention, 4 control). The messages were delivered successfully (98 %), at A$11 per participant. Participants reported appropriate message content (75 %), language (80 %) and delivery timing (97 %).

CONCLUSION

This customised text message intervention was a feasible and acceptable method for improving contact lens compliance.

How Can We Better Inform Patients of the Importance of Contact Lens Compliance?: Current Perspectives

Compliance with contact lens care is important for successful contact lens wear and for minimizing the risk of complications related to lens wear. There are many components of overall lens care guidelines that may potentially be disregarded, forgotten, or misunderstood. Literature has reported copious data on rates of poor compliance for separate lens care recommendations. Knowing the areas of contact lens care where lens wearers perform poorly is helpful when creating strategies for improving patient education. As science evolves and new best-practices are determined, eye care providers must be engaged in educating new lens wearers and reeducating existing wearers. It is vital to make wearers mindful of proper lens care and why proper lens care should be important to them. Various educational strategies can help practitioners to communicate with their patients more effectively. The purpose of this narrative review is to discuss studies of noncompliance with contact lens wear; consequences of these noncompliant behaviors; and studies of lens care education which were found with a literature search. The resulting discussion also includes strategies to improve compliance with patient contact lens wear.

Hand-Washing Habits in a Sample of Spanish Soft Contact Lens Wearers

Contact lens (CL) wear is a safe method for the correction of refractive errors. However, rare, severe ocular complications may occur which may lead to visual loss. As most of these complications are related to poor patient compliance with care and maintenance instructions, resulting in the contamination of hands, CLs and accessories, it was the purpose of this study to assess hand-washing habits in a sample of Spanish soft CL wearers. Hand hygiene was explored through a self-reported online survey and via an in-office practical demonstration in a subset of those users answering the survey. A total of 198 surveys were analyzed, and 18 CL users participated in the practical demonstration. Overall, hand-washing habits were not adequate, with 35 (17.8%) and 103 (52.2%) participants reporting not always washing their hands prior to CL or storage case manipulation, respectively. While 161 (81.3%) participants dried their hands after washing, 132 of these (82.1%) used non-disposable cloth towels. Participants receiving specific hand-washing information from their practitioners (141, or 71.1%) had better hand hygiene (p < 0.05). During the practical demonstration, 13 (72.2%) participants used water and soap to wash their hands, but only 3 (16.7%) displayed correct hand washing routines. Complete patient education, as well as practical reminders at all follow-up visits, are essential to ensure better hand hygiene in order to reduce the probability of ocular complications and to guarantee safe and satisfactory CL use.

Microbial Contamination in Contact Lenses, Lens Care Solutions, and Accessories Among Asymptomatic Soft Contact Lens Users

Objective This study aimed to evaluate microbial contamination of contact lenses (CL) and their accessories among asymptomatic lens users and identify behavioral risk factors that might exacerbate the said contamination. Methodology Ninety-five asymptomatic soft CL users were recruited. In total, 380 samples were collected from the inner surface of lenses, the base of lens cases, the tip of the multipurpose solution bottle, and the solution itself. All swabs with samples were inoculated onto Columbia 5% sheep blood agar, MacConkey agar, Pseudomonas agar with cetrimide, and Sabouraud dextrose agar. Blood agar, MacConkey agar, and Pseudomonas agar with cetrimide were incubated at 37 °C for 24-48 hours. Fungal growth was investigated on Sabouraud dextrose agar, incubated at 25 °C, and examined daily for three weeks. Microscopic examination, culture-based methods, and biochemical tests were used to identify isolated microorganisms. A self-administered questionnaire on compliance with care and hygiene procedures was completed by each participant. Results The overall microbial contamination of tested samples was 38.7%. The most frequently contaminated items were lens cases (59, 62.1%), followed by bottles (44, 46.3%) and lenses (35, 36.8%). Meanwhile, the lowest incidence of contamination was seen in lens multipurpose solutions (9, 9.5%). The predominant microorganisms recovered were Coagulase-negative Staphylococci (CoNS) (94, 64%) and Gram-positive rods (29, 19.7%). Other identified potential pathogens were Staphylococcus aureus (11, 7.5%), Pseudomonas aeruginosa (5, 3.4%), Escherichia coli (1, 0.7%), and Candida albicans (2, 1.4%). The questionnaire revealed that contact lens users aged 18 to 20 showed a lack of compliance with proper hygienic care for contact lens maintenance. Risk factors such as male gender, smoking, showering, or swimming while wearing CL were related to microbiological contamination in at least one of the samples (P > 0.05). Conclusions The highest degree of contamination with highly virulent pathogens was determined in lens cases owing to insufficient lens care practices among study participants. Noncompliance with the lens cleaning procedures can lead to microbial colonization of the lens and its accessories, prompting inflammatory events in the eyes in the future.

Compliance of Soft Contact Lens Care and Bacterial Contamination Among University Students in Palestine

PURPOSE

This study investigated the contact lens care compliance, noncompliance reasons, bacterial contamination rate, and the behaviors associated with contamination among university students in Palestine.

PATIENTS AND METHODS

133 Habitual soft contact lens wearers were recruited in this study and interviewed using a face-to-face questionnaire, to obtain data on demographics, contact lenses, modifiable lens care behaviors and the reasons for non-compliance. High, moderate, and low lens care behaviors were identified. Additionally, a sample of the participant's storage cases was collected for bacterial contamination testing.

RESULTS

The participants' mean age was 22.4±4.4, with female predominance (62.4%). The average compliance rate was 76.8%. Total CL care compliance (100%) was found in filling the case with adequate solution, not sharing the lenses or storage case with others, while the poorest compliance (>40%) was found in attending after-care visits, checking the solution's expiry, and re-disinfecting the lenses with a fresh solution before insertion after prolonged storage. Poor understanding of the instructions contributed significantly to a low level of compliance (P≤0.05). Gram-positive and gram-negative bacteria were detected in 19.55% of the participants' cases. Poor hand and case hygiene, no replacement of lens cases (monthly), and water exposure were linked to bacterial contamination of storage cases.

CONCLUSION

This study indicated moderate to high compliance in CL care, averaging 76.8%. Poor compliance was found in attending after-care visits, checking the solution's expiry, and re-disinfecting the lenses with a fresh solution after an extended storage interval. 19.55% of the cases had bacterial contamination, with Staphylococcus Aureus being the most common. Poor hand and lens case hygiene and water exposure are found to be associated with lens case contamination. These findings emphasize the importance of patient education on safer lens wear modalities, proper wearing schedules, and hygiene regimens to reduce the risks of developing contact lens complications.

Reduction of disinfection efficacy of contact lens care products on the global market in the presence of contact lenses and cases

Objective

Sight-threatening infections can be caused by pathogenic micro-organisms colonising the cornea, leading to microbial keratitis (MK). These micro-organisms can be introduced to the eye via improper contact lens use and care. MK can also result from ineffective contact lens care solutions (CLCs), even if the patient is following best practice guidelines. Therefore, it is critical to understand the differences between the effectiveness of popular CLCs on the global market.

Methods and analysis

Following the International Standards Organisation standards 14 729 and 18259, bacteria (Pseudomonas aeruginosa, Serratia marcescens, Staphylococcus aureus), fungi (Candida albicans, Fusarium strains) and Acanthamoeba strains were inoculated into each CLC with and without contact lenses, and held for the manufacturer’s stated disinfection time. Plate counts were conducted to determine the number of surviving micro-organisms.

Results

All CLCs examined met the primary log reduction criteria during stand-alone testing for Pseudomonas, Staphylococcus, Candida and Fusarium. renu Multiplus, All Clean Soft, and Kombilösung Super did not meet the primary criteria when challenged with Serratia. Only OPTI-FREE Express exceeded 4 log reduction for both strains of Acanthamoeba tested. We noted a substantial reduction in disinfection efficacy when CLCs were challenged with Fusarium in the presence of lenses and cases versus stand-alone testing. OPTI-FREE Express demonstrated significantly less net log reduction loss than the other four CLCs tested.

Conclusion

Of the popular CLCs on the global market, the product which relies on dual biocides polyquaternium-1 and myristamidopropyl dimethylamine demonstrated the highest disinfection efficacy in microbial disinfection challenges in the absence and presence of contact lenses.

Comparison of compliance with care procedures performed by orthokeratology wearers and their parents and factors affecting compliance

PURPOSE

To compare the levels of compliance with care routines of orthokeratology (ortho-k) wearers and their parents and to identify factors affecting compliance in a hospital setting in Chengdu, China.

METHODS

Patients who had worn ortho-k lenses for at least one month were invited to participate in a survey on compliance. Wearers or their parents were required to complete a questionnaire to determine their compliance with hand hygiene, ortho-k lenses and accessory care procedures.

RESULTS

A total of 200 wearers, 78 male wearers and 122 female wearers, median age 12 (range 8-18) years were enrolled. Except for use of lens solution, the percentage of participants reporting total compliance with all procedures did not differ significantly between lens wearers and their parents. However, compliance for some items was significantly higher when performed by parents p < 0.001-0.01). 'Eye care practitioner provided instructions' was a significant protective factor for most procedures (p < 0.001-0.04). Age and sex were significant risk factors for some items (p < 0.001-0.04; p = 0.03-0.04, respectively), with girls having higher compliance than boys. 'Parental supervision' was a significant protective factor for some items (p = 0.02-0.04) when wearers performed the procedures themselves. When parents performed lens care procedures, only 'eye care practitioner provided instructions' was a significant variable (p = 0.001-0.04).

CONCLUSION

Some degree of non-compliance was noted in the majority of ortho-k wearers, particularly for the care of the lens case and suction holder. Compliance with care of some items was higher when performed by parents. Regular reinforcement of care procedures by practitioners is important, especially for older and male lens wearers. Parental supervision is necessary when children perform lens care procedures themselves, even for older wearers.

Addressing common myths and misconceptions in soft contact lens practice

Advances in contact lens technology over the past 50 years since the commercialisation of the first soft lenses in 1971 have been incredible, with significant changes in contact lens materials, frequency of replacement, care systems and lens designs occurring. However, despite the widespread availability of contact lenses, penetration rates for those who need vision correction remain in the low single digits and many practitioners seem to hold on to concepts around the potential value of contact lenses that appear based in the dim and distant past and are certainly no longer valid today. This review addresses 10 common 'myths and misconceptions' around soft contact lenses using an evidence-based approach that can hopefully dispel some of these incorrect assumptions.

Effect of Water Exposure on Contact Lens Storage Case Contamination in Soft Lens Wearers

SIGNIFICANCE

Water exposure during contact lens wear can transfer pathogenic microorganisms to the eye, causing ocular complications. This study determined that water exposure is prevalent among lens wearers and is independently associated with higher case contamination. Contact lens compliance education to minimize water exposure should be reenforced by contact lens organizations and practitioners.

PURPOSE

Given the increasing association between water exposure and contact lens disease, this study aimed to explore the effect of water exposure and storage case contamination in soft contact lens users.

METHODS

A total of 165 daily soft lens wearers completed a self-administered questionnaire on contact lens hygiene. Lens cases were collected, and microbial analysis was conducted using an adenosine triphosphate assay (for overall microbial bioburden) and limulus amebocyte lysate assay (for endotoxin levels). The lens hygiene (excellent, >35; moderate, 28 to 35; poor, <28) and water contact (≤1, good; >1, poor) scores measured the compliance and water exposure during lens wear, respectively. Multiple regression determined the association between water behaviors and case contamination.

RESULTS

The average (standard deviation) age of participants was 28 (13.5) years (18 to 78 years), and 65% were female. The average overall microbial bioburden of storage cases was 3.10 (0.98) log colony-forming unit/mL (1.09 to 5.94 log colony-forming unit/mL). Forty-five percent of participants reported showering, 49.7% reported swimming while wearing lenses (65.4% of whom swam without goggles), 27.8% used wet hands to handle lenses, and 17.5% used tap water to rinse storage cases. Showering with lenses significantly increased the risk of higher storage case bioburden (P = .001), whereas using wet hands (P = .01) doubled the risk of higher case endotoxin levels (odds ratio, 2.41; confidence interval 1.19 to 4.86).

CONCLUSIONS

Water contact behavior while wearing lenses is prevalent among soft lens wearers and is associated with higher case contamination. Practitioners may improve contact lens education to reduce water exposure and case contamination to reduce the risk of lens-related adverse events.

Regular soft contact lens wearers' comprehension of graphical symbols labelled on multipurpose solutions

CLINICAL RELEVANCE

Symbols are commonly used to represent information of health care products included multipurpose solutions (MPSs) for contact lens (CL) care.

BACKGROUND

Little knowledge is available about recognition and comprehension by regular soft CL wearers of commonly used symbols in the instructions of CL MPSs marketed worldwide.

METHODS

CL wearers from the UK and Spain were invited to answer an anonymous on-line questionnaire (distributed though Facebook and Twitter) concerning the recognition and comprehension of seven common symbols (ISO 15223:2017 and EN 980:2008) included in MPS package instructions.

RESULTS

Answers of one hundred-ten soft CL wearers who use MPS (27 in the UK and 83 in Spain) were analysed showing low recognition and comprehension of the surveyed symbols even in wearers with > 5 years of CL wear (71.8%). The CE marked was the most recognised (96% in the UK and 88% in Spain, P = 0.29) and understood (78% in the UK and 85% in Spain, P = 0.25) symbol, but other important symbols, such as 'Caution' and 'Do not reuse', were under recognised (22% in the UK and 19% in Spain, P = 0.78 and 11% in the UK and 6% in Spain, P = 0.40 respectively) and understood (close to 30% in both countries P > 0.15). Participants with > 5 years of experience, showed slightly higher comprehension (P < 0.05) in some symbols ('Sterilised'; 'Do not reuse'; 'Use by date' and 'CE marked').

CONCLUSION

These results suggest an insufficient comprehension of seven common symbols included in MPS instructions among regular CL wearers in the UK and Spain without high impact of CL wear experience. Improving the education and symbol comprehension of regular CL wearers could help to get better patients' behaviour and safe use of MPS in soft CLs care.

CLEAR - Evidence-based contact lens practice

Evidence-based contact lens -->practice involves finding, appraising and applying research findings as the basis for patient management decisions. These decisions should be informed by the strength of the research study designs that address the question, as well as by the experience of the practitioner and the preferences and environment of the patient. This reports reviews and summarises the published research evidence that is available to inform soft and rigid contact lens history and symptoms taking, anterior eye health examination (including the optimised use of ophthalmic dyes, grading scales, imaging techniques and lid eversion), considerations for contact lens selection (including the ocular surface measurements required to select the most appropriate lens parameter, lens modality and material selection), evaluation of lens fit, prescribing (teaching self-application and removal, adaptation, care regimen and cleaning instructions, as well as -->minimising risks of lens wear through encouraging compliance) and an aftercare routine.

The impact of patient behaviour and care system compliance on reusable soft contact lens complications

Reusable soft daily wear contact lenses (CLs) remain popular and were fit to just over half of all wearers in the most recent international CL prescribing survey. Unlike daily disposable CLs, reusables require cleaning and disinfecting after every use, along with storage in a CL case. These additional requirements add a number of steps to the daily wear and care routine, increasing the opportunities for CL wearers to exhibit non-compliant behaviour. The impact of non-compliance ranges from poor lens comfort through to potentially sight-threatening infective keratitis. The coronavirus pandemic has refocused the profession on the importance of hand hygiene in particular, and the need for promoting safe CL wear in general. This review summarises typical non-compliant behaviour related to reusable CLs, and examines strategies and opportunities to better support wearers. Patient education has a central role in encouraging compliant behaviour, although patient recall of information is low, and personal belief systems may result in continuation of non-compliant behaviour despite awareness of the risks. CL care solutions are required for the daily disinfection of lenses, however misuse of multipurpose solutions (MPS) and hydrogen peroxide (H₂O₂)-based care systems can challenge their ability to be fully efficacious. Standard efficacy testing is reviewed, with consideration of how well current protocols model real-world use of CL solutions. Although some recommendations are in place for the inclusion of additional variables such as lens cases, CL materials, organic soil and efficacy against Acanthamoeba, opportunity still exists to reevaluate global standards to ensure consistency of testing in all markets. Finally, potential future innovations are discussed which may further support increased safety in reusable lens wear through novel antimicrobial additions to both CL materials and cases.

Could telehealth help eye care practitioners adapt contact lens services during the COVID-19 pandemic?

The COVID-19 pandemic has necessitated government-imposed restrictions on social interactions and travel. For many, the guidance has led to new ways of working, most notably a shift towards working remotely. While eye care practitioners (ECPs) may continue to provide urgent or emergency eye care, in many cases the travel restrictions present a unique challenge by preventing conventional face-to-face examination. Telephone triage provides a useful starting point for establishing at-risk and emergency patients; but patient examination is central to contact lens patient care. The indeterminate period over which conventional practice will be suspended, and the risk that resumption of 'normal' practice could be impeded by a potential secondary peak in COVID-19 cases, hastens the need for practitioners to adapt their delivery of eyecare. Specifically, it is prudent to reflect upon supportive evidence for more comprehensive approaches to teleoptometry in contact lens practice. Smartphone based ocular imaging is an area which has seen considerable growth, particularly for imaging the posterior eye. Smartphone imaging of the anterior eye requires additional specialised instrumentation unlikely to be available to patients at home. Further, there is only limited evidence for self-administered image capture. In general, digital photographs, are useful for detection of gross anterior eye changes, but subtle changes are less discernible. For the assessment of visual acuity, many electronic test charts have been validated for use by practitioners. Research into self-administered visual acuity measures remains limited. The absence of a comprehensive evidence base for teleoptometry limits ECPs, particularly during this pandemic. Knowledge gaps ought to be addressed to facilitate development of optometry specific evidence-based guidance for telecare. In particular, advances in ocular self-imaging could help move this field forwards.

Hand hygiene is linked to microbial keratitis and corneal inflammatory events

Lack of or inadequate hand washing is a risk factor in the development of contact lens related microbial keratitis and corneal inflammatory events. In the public health domain there is compelling evidence that proper hand washing with soap can save lives. The purpose of this review is to draw attention to some of the public health literature in support of hand washing and how education can influence patients' hand hygiene behavior. Contact lens wearers are also guilty of poor hand washing behavior but there is scant evidence that education of hand washing procedures of lens wearers alters patient non-compliance. It is well known that pathogenic microbial contamination of contact lenses, lens cases, care solutions and anterior ocular components have been found with contact lens wear. However while the originating source may be hands or water, it is most likely both of these. Besides proper hand washing this paper will include mitigating strategies for avoiding microbial contamination.

Bacterial Bioburden Decrease in Orthokeratology Lens Storage Cases After Forewarning: Assessment by the DNA Dot Hybridization Assay

BACKGROUND

The aim of this study was to measure the changes in the bacterial bioburden in orthokeratology (OK) lens storage cases using the DNA dot hybridization assay (DHA) after forewarning patients about their bacterial contamination severity.

METHODS

Thirty-one OK lens wearers were prospectively enrolled in this study. Dot hybridization assay was used for serial measurements of bacterial bioburden in OK storage cases after lenses had been soaked for approximately 6 hr. After the first assessment, the lens wearers were informed of the extent of case contamination and the possible risk of microbial keratitis (MK), and best practices for lens care and lens case hygiene were reviewed and reinforced. A second assessment by the same DHA method was performed after approximately 6 months.

RESULTS

Two universal bacterial probes confirmed a significant decrease in bacterial bioburden at the second assessment (P<0.01 and P<0.001). Genus-specific probes showed significant reductions in Acinetobacter and Klebsiella (P=0.02 and P=0.01), but not in Pseudomonas (P=0.42).

CONCLUSIONS

Making OK lens wearers aware of the bacterial bioburden in their lens cases resulted in improved quality of case care and reduced bioburden. Our results suggest that a strategy of bioburden assessment with forewarning could be a useful method to decrease the incidence of OK-related MK.

Contact Lens Care among Teenage Students in Italy: A Cross-Sectional Study

AIM

To assess the attitude and practice of contact lens (CL) wearers among teenage school students and to evaluate how much the teenagers adhere to the CL care procedures according to the proper care of CL guidelines.

METHODS

A cross-sectional descriptive study of Italian teenagers from high schools in Rome who wear CL. We inquired about the different aspects of CL care through a questionnaire.

RESULTS

We investigated 3,106 students from high schools in Rome (2% of all Roman high school students), 293 of whom wore CL (9%); 151 (52%) of participants responded, 42 (27.8%) male and 109 (72.8%) female. The mean age was 16.4 ± 1.6 years. 79.5% of students were daily users. 45.7% wore CL more than nine hours/day. 87.4% wore soft CL. 33.1% wore disposable CL; 7.9% weekly CL, 55% monthly CL. Thirty-four percent wore disposable lenses twice or more. 14.5% of students did not wash their hands before handling CL and 52.3% wore CL after it had fallen in the sink. 39.7% rubbed and cleaned CL before storing it. 10% used expired lens care solutions. Only 31.1% changed CL cases every three months. 38.4% wore CL in a swimming pool. 61.6% were having problems: redness (13.9%), itching (7.9%), and foreign body sensation (29.1%).

CONCLUSION

Many students don't properly care for their CL. Education regarding proper care and management of CL among users is advised in view of frequency of symptoms and complications reported.

The use of daily disposable lenses in problematic reusable contact lens wearers

PURPOSE

Replacing soft contact lenses (CLs) on a daily basis brings a number of advantages, most notably, reduced exposure to deposits, disinfectants, allergens, and other contaminants. This retrospective study estimated the prevalence of problems in current wearers of reusable soft CLs and tested the effect of refitting "problem" patients with daily disposable (DD) hydrogel lenses.

METHODS

Prevalence was estimated from 398 current reusable CL wearers for: frequent/constant discomfort or dryness, ≥2 h of uncomfortable wear, ≥grade 2 conjunctival hyperaemia (0-4), or ≥grade 3 corneal staining (0-15). In the second part of the study, 217 reusable CL wearers classified as problem patients were randomly refitted with DD lenses manufactured from one of two materials: etafilcon A (n=96) or nelfilcon A (n=121) and reassessed 1 week later.

RESULTS

Thirty-nine percent (154/398) had some qualifying criterion: reduced comfortable wearing time (CWT), 20%; dryness, 20%; irritation, 5%; corneal staining, 8%; and hyperaemia, 7%. After refitting with DDs, the prevalence of reduced CWT was decreased from 65% to 51% (P=0.0039), dryness from 60% to 41% (P < 0.0001) and corneal staining from 28% to 21% (P=0.04). There was no significant change in the prevalence of irritation, or hyperaemia. Some differences were noted between the two lens materials.

CONCLUSIONS

A high proportion of reusable soft lens wearers encounter clinically relevant signs or symptoms with their current CLs. This study provides evidence that refitting with DD lenses is a useful strategy for alleviating some of the common problems of CL wear.

Demographics and Behaviour of Patients with Contact Lens-Related Infectious Keratitis in Singapore

Introduction: This study aims to identify the demographics and hygiene behaviours associated with contact lens (CL)-related microbial keratitis in Singapore. Materials and Methods: The hygiene and social behaviours of lens wearers presenting with infectious keratitis in Singapore were examined using an externally validated questionnaire. Fifty-eight consecutive lens wearers who presented with infectious keratitis at Singapore National Eye Centre were surveyed using a self-administered questionnaire. Patients’ demographics, CL-related behaviour, attitude to aftercare visits and microbial study results were collected and analysed. Results: More than half (55%) of the patients surveyed were female, and the average age of the participants was 25.7 ± 6.4 years. Ninety-six percent of participants used soft CL, with the majority wearing monthly disposable lenses (74.1%). Myopia was the commonest reason for use of CL. CL overwear (81%), sleeping (50.9%) and swimming (33%) with their CL were the major non-compliant behaviours discovered. When encountered with eye discomfort as a result of lens-related infective keratitis, 83% of patients sought the advice of general medical practitioners prior to presentation at the hospital. Many (59%) patients have encountered media coverage but only 24% had any behavioural change as a result. Many patients relied on the recommendations of eyecare practitioners when purchasing disinfecting solutions (26%) and other hygiene practices. Pseudomonas Aeruginosa was the most common organism grown in 22.4% of patients while 47% of patients were culture-negative. Conclusion: Inadequate lens cleaning, poor aftercare, sleeping and swimming with CL were the major non-compliant behaviours among participants, and these are significant factors when assessing risks in acquiring CL-related infectious keratitis. General eyecare practitioners are the first-line of contact in patients presenting with keratitis symptoms and play an important role in emphasising the need for regular aftercare and good hygiene practices to CL wearers. Key words: Contact lens, Corneal ulcer, Infective keratitis

Microbial contamination of contact lens care accessories and compliance with care regimens in Nepal

PURPOSE

To determine the rates of microbial contamination and identify contaminants associated with contact lens (CL) care accessories. To investigate self-reported compliance levels with care of CL accessories and its association with contamination level.

METHODS

A total of 46 CL cases and care solutions from asymptomatic soft contact lens wearers were collected. Samples from the CL cases and care solutions were cultured for microbiological identification and enumeration. A questionnaire regarding compliance to care and hygiene procedures were administered to each subject on their visit.

RESULTS

The percentage of microbial contamination for CL cases and care solutions was 50% and 10.9%, respectively. All the contaminants were bacterial. Staphylococcus aureus (37.0%, 17 of 46 cases) and Escherichia coli (8.7%, 4 of 46 cases) were the most common microorganisms detected in CL cases. In care solutions, S. aureus (8.7%, 4 of 46 samples), Pseudomonas aeruginosa (2.2%, 1 of 46 samples) were common contaminants. CL cases and care solutions that were used for <3 months were significantly less contaminated than those used for >3 months (10.9% versus 39.1%, p<0.05). Polyquad and Aldox based MPS solution showed no contamination. Subjects with medium or low compliance had highly significant rates of contaminations both in CL cases and solutions than for subjects with high compliance (p<0.05).

CONCLUSIONS

Nepalese Soft CL wearers are at high risk of developing ocular complications due to high CL case and solution contamination. Frequent replacement of CL cases and solutions, as well as good compliance is recommended to reduce risk of contamination.

Non-compliance with contact lens wear and care practices: a comparative analysis

PURPOSE

To compare the effects of existing patient awareness of lens-related complications and underlying risk factors on actual patient behavior during contact lens wear and care practices in two different clinical study populations.

METHODS

Established contact lens wearers (n = 281) completed an anonymous written questionnaire on presenting to their habitual eye care practitioner in the Dallas-Fort Worth metroplex. Data were analyzed and compared against a second study population, which comprised established contact lens wearers (n = 152) who were sequentially evaluated after their routine contact lens examination at the University of Texas Southwestern Medical Center at Dallas, TX (UTSW). All patients were questioned regarding his or her lens care practices and knowledge of complications and risk factors associated with contact lens wear.

RESULTS

Fifty-eight percent of patients in the general community could identify by name a complication associated with lens wear compared with 91% within the medical center. The most frequent complications reported were related to comfort and handling (72%, Dallas-Fort Worth) and infection (47%, UTSW). The majority of patients could correctly identify risk factors associated with lens-related complications; awareness for topping-off solutions, tap water exposure, and hygiene varied between groups. Overall, 85% of patients perceived themselves as compliant with their lens wear and care practices. Using a standard scoring model to determine actual compliance, 2% of patients demonstrated good compliance; however, only 0.4% of patients were fully compliant with contact lens wear and care practices.

CONCLUSIONS

The data reveal some study bias in complication and risk awareness between populations; however, despite this limitation, a significant proportion of patients exhibited actual non-compliant behavior despite acknowledged awareness of risk. Although most patients consider themselves to be complying with standard practitioner guidelines for lens wear and care practices, essentially all contact lens wearing patients exhibit behavioral non-compliance with resulting increased risk for significant complications.

Contamination risk of reusing daily disposable contact lenses

PURPOSE

This study investigated contamination of saline and daily disposable contact lens (DDCL) stored overnight after use in the original blister pack and the practices of a group of DDCL users.

METHODS

Twenty DDCL wearers placed their lenses after 1 day's use back into the blister pack saline (BPS) and left them overnight before transferring both lens and BPS to a new CL case. The lens and BPS were cultured the following day, and total number of organisms, Staphylococci, and gram negative organisms enumerated. Each subject submitted five pairs of lenses over a 1 month period.

RESULTS

Ninety-five percent of subjects had at least one pair of contaminated lenses, and the BPS yielded similar results to the contaminated lenses, with staphylococcal contamination being predominant. Three subjects admitted to not washing their hands before handling their lenses and six to habitual reuse of their lenses with storage in the BPS. There was a higher risk of contamination in male subjects.

CONCLUSIONS

Reuse of lenses poses an important risk for DDCL users because they are unlikely to have received proper training in cleaning and disinfection of lenses and do not use a lens case or disinfecting solutions. Overnight storage in BPS results in contaminated lenses which if reused increases the infection risk especially with Staphylococci. It is important that practitioners carefully educate their patients in correct use of DDCL and, as cost of lenses is a major factor in willingness to reuse, ensure that DDCL is the most suitable choice when prescribing.

Adherence of acanthamoeba to lens cases and effects of drying on survival

PURPOSE

To compare the effects of drying the lens case with tissue on the presence of Acanthamoeba with cases left wet and to determine adherence to the lens case of varying concentrations of Acanthamoeba suspensions. The effect of drying on viability of Acanthamoeba in new, used, and soiled lens cases was compared over a 24 h period.

METHODS

New (16) and scratched (16) lens cases were rinsed with a range of Acanthamoeba suspensions. Eight of each group were dried with tissue and the presence of Acanthamoeba was determined in all cases using polymerase chain reaction. To examine effects of drying, forty-two lens case wells were scratched to simulate use and 21 of these were artificially soiled with serum Bovine albumin. These cases and a further 21 unused wells were contaminated with Acanthamoeba (×10/ml) and then left to dry in a cool, dry environment. Three wells of each group were sampled at time 0, 2, 4, 6, 8, 12, and 24 h, and the number of viable Acanthamoeba were determined.

RESULTS

Acanthamoeba were more likely to adhere to used than unused lens cases (p < 0.05). Detection of Acanthamoeba in wiped lens cases was at 2-log dilutions less than in cases left wet for both new and used lens cases. Adherence were significantly different between rinse and rinse/dried cases (p = 0.015). Air drying significantly reduced the numbers of viable amoebic cysts and trophozoites and the effect was time dependent. Survival was significantly higher in used and soiled wells.

CONCLUSIONS

Drying with tissue after rinsing significantly reduces numbers of adhering Acanthamoeba. Acanthamoeba were found to be able to adhere even to new unused cases, so the importance of proper cleaning and disinfection of lens cases cannot be underestimated. Air drying reduces viability but some viable cells were present at 24 h in soiled cases, confirming the role of biofilm in protecting organisms from desiccation.

Multipurpose solutions and rates of biocidal efficacy

OBJECTIVE

To investigate the hypothesis that reasonable levels of disinfection are achievable over relatively short exposure durations of microorganisms to multipurpose solutions, this study examined the stand-alone disinfection efficacy at 10, 20, and 30 min of five different multipurpose solutions products, each against five different pathogens eye care practitioners may encounter in their contact lens practice.

METHODS

ReNu MultiPlus, ReNu Multi-Purpose, AQuify, OptiFree Express, and OptiFree RepleniSH were evaluated for their microbiocidal efficacy using the stand-alone method at 10, 20, and 30 min of exposure to either Fusarium solani, Candida albicans, Staphylococcus aureus, Serratia marcescens, or Pseudomonas aeruginosa.

RESULTS

Solutions which showed significantly higher rates of disinfection at 30 min were ReNu MultiPlus against Fusarium solani and Candida albicans, and both ReNu MultiPlus and AQuify against Staphylococcus aureus and Serratia marcescens. There were no statistically significant differences at 30 min amongst solutions against Pseudomonas aeruginosa.

CONCLUSIONS

The product attribute of rapid rate of disinfection may give a greater level of assurance to practitioners when patients are noncompliant and do not follow the recommended time period for lens disinfection. The results of this study, however, should not be interpreted as a recommendation to use any of the solutions tested for a disinfection period less than the recommended soak time. Patient compliance with recommended lens care regimens is essential in minimizing the risk of contamination of contact lenses and lens care accessories.

Patient compliance during contact lens wear: perceptions, awareness, and behavior

OBJECTIVES

Patient noncompliance with recommended hygienic practices in contact lens wear is often considered a significant risk factor for microbial keratitis and adverse contact lens-related events. Despite advancements in lens materials and care solutions, noncompliant behavior continues to hinder efforts to maximize contact lens safety. The objective of this pilot study was to assess the relationship between perceived and actual compliance with awareness of risk and behavior.

METHODS

One hundred sixty-two established contact lens wearers were sequentially evaluated after their routine contact lens examination at the Optometry Clinic at the University of Texas Southwestern Medical Center at Dallas, TX. Each patient was questioned by a single trained interviewer regarding his or her lens care practices and knowledge of risk factors associated with lens wear.

RESULTS

Eighty-six percent of patients believed they were compliant with lens wear and care practices; 14% identified themselves as noncompliant. Using a scoring model, 32% demonstrated good compliance, 44% exhibited average compliance, and 24% were noncompliant; age was a significant factor (P = 0.020). Only 34% of patients who perceived themselves as compliant exhibited a good level of compliance (P<0.001). Eighty percent of patients reported an awareness of risk factors, but awareness did not influence negative behavior. Replacing the lens case was the only behavior associated with a positive history for having experienced a prior contact lens-related complication (P = 0.002).

CONCLUSIONS

Perceived compliance is not an indicator for appropriate patient behavior. A large proportion of patients remain noncompliant despite awareness of risk. Education alone is not a sufficient strategy to improve behavior; newer approaches aimed at improving compliance with lens care practices are urgently needed.