The 2020 Global Specialty Lens Symposium (GSLS) covered a range of specialty contact lens topics, from myopia management and practice management to the ocular surface and ocular pain. This article will review the lectures that focused on my personal favorite topic: contact lens hygiene and care.

BUGS ALL AROUND

Some common eyecare procedures that may contribute to the spread of infection include foreign body removal, gonioscopy, and diagnostic contact lens fitting. In “‘Bugs All Around,’ A New Era in Standards for Contact Lens Practice,” Louise Sclafani, OD, and Loretta Szczotka-Flynn, OD, PhD, discussed strategies to mitigate these in-office infection risks, including the latest standards for disinfecting diagnostic contact lenses.

Dr. Szczotka-Flynn presented data from a study to detect the human adenovirus pathogen among inpatients in an ophthalmology ward.¹ The researchers found that mild or asymptomatic infection is common during conjunctivitis outbreaks and may contribute to nosocomial infections. A separate study reported a five-fold increased risk of corneal inflammatory events (CIEs) in daily soft contact lens wearers who had substantial lid margin bacterial bioburden.² Specifically, the frequency of substantial lid margin bioburden was about 11% for both coagulase-negative staphylococci (CNS) and Staphylococcus aureus among CIE-free soft contact lens wearers, while patients in the CIE group presented with lid margin bioburden frequencies of 23% for CNS and 8.7% for S. aureus. These findings are important reminders that even asymptomatic patients may contribute to the spread of disease; therefore, thorough disinfection of medical equipment and devices is paramount.

This topic segued into Dr. Sclafani’s discussion of the comprehensive standards for disinfection of diagnostic contact lenses that were recently developed by the International Organization for Standardization (ISO). The ISO is an independent, non-governmental organization that develops voluntary, consensus-based, market-relevant international standards. The contact lens fitting process can lead to pathogen transfer when lenses are reused on multiple patients; therefore, standardized guidelines were needed.

ISO 19979:2018 applies to reusable soft, rigid (GP and PMMA), and hybrid contact lenses.³ Not only are these standards important for preventing the spread of infection, but as Dr. Sclafani explained, without written protocols in place, the Centers for Disease Control and Prevention recommends disposal of diagnostic lenses after each use. She noted that disposal of diagnostic lenses is still recommended under certain conditions including cases of hepatitis, human immunodeficiency virus (HIV), prion disease, adenovirus, Acanthamoeba keratitis, herpes ocular infection, and active bacterial or fungal infection.

The process for cleaning and disinfecting diagnostic lenses (Table 1) begins with thorough handwashing and the use of gloves. The lenses should not be returned to their storage containers following use. Rather, they should be placed temporarily in a disposable container until they are cleaned.

Lenses of all materials should be cleaned with a surfactant cleaner, rinsed with saline or multipurpose solution (MPS), and visually inspected for damage or defects. All lenses and associated vials, stoppers, and plungers should be soaked in non-neutralized, ophthalmic grade, 3% hydrogen peroxide for three hours. Following this step, GP and PMMA lenses should be rinsed with saline or MPS and stored dry in a disinfected case. Hybrid and soft lenses should be transferred to a new case with fresh hydrogen peroxide solution and neutralized as recommended by the solution manufacturer. After neutralization, these lenses should be rinsed with saline or MPS and stored in a sealed container with fresh MPS.

The ISO standard recommends comprehensive documentation and labeling of lens vials. Lens parameters, material, and last date of disinfection should be written on each lens vial. A separate log should be maintained for each fitting set, noting how and when disinfection took place, the dates of use, and a patient reference for each trial lens. Any lens that is stored wet should be disinfected every 28 days.

Given the cumbersome nature of this process, which requires additional time and resources, Dr. Sclafani encouraged practitioners to use single-use trial lenses when available, to attempt empirical fitting whenever possible, and to appeal to contact lens manufacturers to produce inexpensive diagnostic lens sets. She noted that the Section on Cornea, Contact Lenses and Refractive Technologies of the American Academy of Optometry and the Contact Lens & Cornea Section of the American Optometric Association plan to collaborate on a publication to help decipher and outline the ISO standards.

SPECIALTY LENS CARE

The penultimate GSLS general session, “A 2020 Vision on Specialty Lens Care,” focused on the often undervalued topics of contact lens care, maintenance, and safety. Much of a patient’s success with specialty contact lens wear depends on lens hygiene, handling, and the use of appropriate care solutions and accessories. During this two-part session, the academic team presented the best and most conservative approaches, and the clinical team translated these recommendations into realistic and feasible practices.

In his opening remarks, co-moderator Eef van der Worp, BOptom, PhD, noted that the exponential increase in scleral lens publications over the last few years demonstrates the increased global popularity of this lens type.⁴ He proceeded to discuss some of the well-established microbial keratitis (MK) incidence data for corneal GP lenses and for daily and extended wear soft lenses. He also noted that the incidence of MK in orthokeratology lenses is roughly between that of daily wear and extended wear soft lenses. Importantly, no such data exist concerning the incidence of infectious events in scleral lens wear.

Dr. van der Worp explained that although lens fit, design, material, and oxygen permeability are important factors to consider during the fitting process, they have little impact on the potential for infectious corneal conditions. This is where the necessity of proper lens handling and care is realized.

Co-moderator Karen DeLoss, OD, introduced the topic of specialty contact lens exposure to water by presenting data from The Dry Eye Foundation.⁵ The results from these patient surveys indicate that not only are patients regularly exposing their lenses and lens accessories to tap water, but very few practitioners are discussing the risks of tap water exposure with patients.

BEST PRACTICES

As a presenter for the academic team in this session, I kicked off the academic viewpoint with a discussion of patients’ contact lens hygiene compliance. Although about 85% of patients report good compliance with lens hygiene practices,⁶ in reality, almost all lens wearers exhibit at least one risky hygiene-related behavior.⁷

Before discussing any contact lens-specific practices, it is crucial to emphasize the importance of proper hand hygiene. Thorough handwashing is the single most important means of preventing infection in a hospital setting, and the same can be said for private practice and academic settings. Studies have reported the associations between poor hand hygiene and keratitis risks: 50% higher risk for contact lens-associated MK and 90% higher risk for contact lens-associated CIEs.^8,9 In addition, the use of soap and water for handwashing is associated with less overall lens case contamination when compared to cases used by patients who either do not wash their hands or who use only water.¹⁰

Tap water has no role in specialty lens care because of the increased risks of infiltrative and infectious conditions associated with water contamination. Despite the recommendation for complete avoidance of tap water, a 2017 study reported that 91% of GP lens wearers and 31% of soft contact lens wearers rinse their lenses with tap water.¹¹ This finding corresponds with the product recommendations included in the majority of inserts for GP lens cleaning and disinfecting systems, 83% of which recommend the use of tap water for rinsing lenses, lens cases, or both.¹² Approximately 60% of practitioners advise patients who wear specialty contact lenses to avoid exposing them to tap water;^13,14 thus, many patients never receive the water-avoidance message from their eyecare practitioners.

Some of the dangers associated with swimming and showering while wearing contact lenses include increased risks of lens storage case contamination, MK, and CIEs. It is also important to instruct patients about proper disinfection of lens accessories, as studies report microorganism contamination of 58% of plungers¹⁵ and 85% of lens storage cases.¹⁶ Discussing these topics with every patient at every visit helps to reinforce best practices.

Lyndon Jones, PhD, DSc, provided the second academic perspective, focusing on care solutions and lens surface treatments. Dr. Jones emphasized the importance of choosing an appropriate care system, particularly because patients who wear specialty lenses often have ocular surface disease and preservative sensitivities. He noted that because of these considerations, many practitioners favor hydrogen peroxide-based systems, a preference that matches the product recommendations from the Scleral Lenses in Current Ophthalmic Practice Evaluation (SCOPE) study.¹³

Lens storage cases can harbor a wide variety of microorganisms, particularly on surfaces that do not regularly come into contact with disinfecting solutions. Dr. Jones presented data from a study that compared the level of bacteria adhered to lens cases after disinfection with a povidone iodine-based solution, a traditional peroxide solution, or a PHMB-containing solution.¹⁷ The hydrogen peroxide and the PHMB-based solutions each demonstrated approximately 1 log unit reduction in colony-forming units (CFUs) on the lens case surfaces. This was in contrast to the povidone iodine-based solution, which demonstrated a 4.7 log unit reduction in CFUs, likely owing to the effect of liberated iodine gas against adhered bacterial species.

Dr. Jones touched on the variety of products suitable for filling scleral lens bowls, including important factors to consider when recommending a filling solution, such as the addition of buffers, the ion content, U.S. Food and Drug Administration approval status, and product volume. He then discussed lens rubbing and rinsing. These steps, which many contact lens wearers fail to complete on a daily basis, result in more effective disinfection by reducing the number of adherent microbial species on the lens surface.¹⁸

A recent study explored the effect of digital rubbing on removing surface deposits from orthokeratology lenses.¹⁹ For this study, researchers applied mascara or hand cream to the lens surfaces to simulate stubborn and loosely bound deposits, respectively. Using a pre-set visible grading scale, masked examiners graded the results after digital rub or no rub with one of two disinfection solutions. Failing to rub the lenses was ineffective in removing the stubborn deposits, regardless of which disinfection solution was tested.

This study demonstrates the importance of including digital lens rubbing as part of proper lens care, and Dr. Jones encouraged practitioners to counsel patients about this key step. He urged practitioners to stay up-to-date with the latest developments in disinfection solutions, application solutions, and lens accessories to ensure the best experiences for patients.

REAL-WORLD APPROACH

In the second half of this GSLS session, Dr. Szczotka-Flynn switched gears and offered practical experiences and clinical pearls for specialty lens care and diagnostic lens storage. She opened by discussing a series of infiltrative keratitis cases among scleral contact lens wearers within her practice. After thoroughly questioning the affected patients, she discovered that they were exclusively using nonpreserved saline to rinse, fill, and store their lenses. These CIEs presented similarly to those in soft contact lens wearers (Figure 1) and were likely associated with CNS, which are part of the normal eyelid and hand flora.

Fortunately, proper hygiene education can address the behaviors that led to these isolated incidents, and Dr. Szczotka-Flynn offered some practical clinical pearls:

• Ask patients to repeat lens care instructions after training.
• Provide patients with written lens care instructions.
• Ask patients to describe their lens care regimen at each follow-up visit.

In addition to giving patients the “no water” stickers available through the AAO and the British Contact Lens Association, Dr. Szczotka-Flynn mentioned an idea she’d heard from Brian Tompkins, BSc(Hons), FCOptom, and Keyur Patel, BSc(Hons), OD, to label care solution bottles with large “clean,” “store,” and “fill” stickers to avoid confusion and misuse by patients.

Dr. Szczotka-Flynn next tackled some common situations and temptations with regard to patients’ lens wear and care, starting with patients who nap while wearing contact lenses. For example, suppose a scleral lens wearer properly disinfects his or her lenses before application and later wants to take a nap but does not have the appropriate supplies on hand. In this situation, Dr. Szczotka-Flynn stated that napping while wearing the lenses is acceptable, particularly considering that scleral lenses are not in direct contact with the corneal surface. This is in stark contrast to a patient who naps while wearing soft contact lenses, a behavior that should prompt the highest level of concern, even with situational naps.

The next example involved needing a diagnostic lens that had not yet been disinfected after a previous patient encounter for a subsequent patient encounter. In this situation, it is not sufficient to disinfect the dirty lens with hydrogen peroxide for a shorter period of time, as its effectiveness directly relates to exposure time to the microorganism. A 10- or 15-minute soak may be sufficient to kill the majority of bacterial species and HIV, but fungal and Acanthamoeba species will still be viable until the lenses have soaked for two hours.²⁰

What about using MPS or neutralized hydrogen peroxide in place of non-neutralized hydrogen peroxide to disinfect in-office diagnostic lenses? The literature does not support this substitution, Dr. Szczotka-Flynn said, and she cited a study that examined the efficacy of traditional disinfection systems against communicable adenovirus types.²¹ After one cycle of disinfection, 100% of lenses tested positive for adenovirus type 19, which is one of the etiologic agents of epidemic keratoconjunctivitis.

Dr. Szczotka-Flynn concluded her presentation by encouraging practitioners to use single-use trial lenses whenever possible and to adapt to empirical fitting when feasible by using technology, consultation services, and nomograms.

Shalu Pal, OD, wrapped up the session by discussing how she implements hygiene recommendations and guidelines into her specialty lens private practice. She considers product availability, staff time, cost efficiency, and practicality when developing her practice strategies. She emphasized the importance of developing clear and consistent hygiene rules for patients to avoid ambiguity and uncertainty. She reviews hygiene and handling instructions at every follow-up visit via verbal discussion and observation of patients’ behaviors, making sure to provide a supportive and helpful environment for patients. She reinforces safe hygiene practices through handouts, video links, emails, and product labels; by providing new lens cases and sample products; and by selling all recommended products at her practice.

Dr. Pal concluded her talk by highlighting the importance of staff support. She encouraged practitioners to invest in their staff by providing training, by bringing staff into the examination room to hear how patients are educated and counseled, and by recognizing and encouraging staff skills, strengths, and autonomy. Dr. Pal empowers her staff by asking them to develop handouts and procedure manuals, by allowing them to develop professional relationships with product representatives, and by encouraging a learning environment.

CONCLUSION

Contact lens care and hygiene may not be as flashy as a new scleral topographer or a multifocal scleral lens, but it is essential to a successful specialty lens fit. Patients are counting on us as their eyecare providers to be up to date with the latest evidence-based recommendations, advances in lens products and accessories, and clinical best practices. Be the example in your practice; your patients will thank you for your care and attention. CLS

REFERENCES

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