SOFT CONTACT LENSES account for the majority of contact lens fittings. According to the Contact Lens Spectrum“International Contact Lens Prescribing in 2023” feature, of 13,127 contact lens fits reported, 90% were soft contact lenses and 75% were silicone hydrogel lenses (Morgan et al, 2024). However, their utilization ranged from as low as 19% of soft lens fittings in Taiwan to as high as 96% in Colombia. Approximately one-third of all contact lenses were monthly replacement lenses. Another publication reported that approximately half of contact lens wearers use reusable lenses, which are replaced every four weeks or more frequently (Jones et al, 2023).
Reusable contact lens wear necessitates proper hygiene and contact lens care. All reusable lenses must be disinfected daily with a solution. According to the Contact Lens Spectrum “International Contact Lens Prescribing” report, 91% of contact lens wearers received a prescription for a multipurpose solution (Morgan et al, 2024).
Noncompliance with appropriate contact lens wear and care is common among wearers. At some point, every contact lens wearer displays at least one hygiene risk behavior (Cope et al, 2015). More than 80% of lens wearers routinely practice noncompliance, which increases their risk of experiencing a serious complication (Cope et al, 2017).
Povidone-iodine, a type of oxidative disinfectant, has been shown to be safe and effective and is utilized in ophthalmic surgery (Itokawa et al, 2024). Povidone-iodine can mitigate some types of adenovirus conjunctivitis by decreasing ocular symptoms and scarring (Itokawa et al, 2024). Povidone-iodine and hydrogen peroxide are the primary disinfecting agents in preservative-free solutions.
The povidone-iodine contact lens disinfecting system developed in Japan has exhibited superior antiviral and antimicrobial properties (Itokawa et al, 2024). Compared to multipurpose solutions, disinfecting solutions with oxidative properties demonstrate higher efficacy (Yasir et al, 2022). Povidone-iodine and hydrogen peroxide are both oxidative solutions.
When compared to multipurpose solutions, both povidone-iodine and hydrogen peroxide provide enhanced antiviral activity against coronavirus unless a complete regimen of rub, rinse, and disinfect is used with the multipurpose solution. Both hydrogen peroxide and povidone-iodine solutions effectively reduce coronavirus counts to less than detectable levels (Yasir et al, 2021).
Povidone-iodine has been used with soft contact lenses since 2001 and with rigid lenses since 2010 (Yamasaki et al, 2020). Typically, iodine is placed in a chemical carrier called povidone to allow the slow release of iodine (Yamasaki et al, 2021). Once iodine reaches a cell, it oxidizes several cellular components and iodinates lipids of the cell membrane. Iodine permeates microbial cell walls, oxidizes their components, disrupts their C–H, N–H, and S–H bonds, and incorporates within the cells to reduce toxicity (Willcox et al, 2021). An ascorbic acid tablet is used with povidone-iodine to finalize neutralization.
With the increased use and diversification of specialty lenses, including scleral lenses and orthokeratology, there is a potential application for povidone-iodine solution, a safe biocide with robust disinfecting efficacy.
REFERENCES
1. Morgan PB, Woods, CA, Tranoudis IG, et al. International Contact Lens Prescribing in 2023. Contact Lens Spectrum. 2024 Jan 1. Available at clspectrum.com/issues/2024/januaryfebruary/international-contact-lens-prescribing-in-2023/. Accessed 2024 July 9.
2. Jones L, Efron N, Bandamwar K, et al. TFOS Lifestyle: Impact of contact lenses on the ocular surface. Ocul Surf. 2023 Jul;29:175-219.
3. Cope JR, Collier SA, Rao MM, et al. Contact lens wearer demographics and risk behaviors for contact lens-related eye infections–United States, 2014. MMWR Morb Mortal Wkly Rep. 2015;64:865-870.
4. Cope JR, Collier SA, Nethercut H, Jones JM, Yates K, Yoder JS. Risk behaviors for contact lens-related eye infections among adults and adolescents - United States, 2016. MMWR Morb Mortal Wkly Rep. 2017;66:841-845.
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6. Itokawa T, Yamasaki K, Suzuki T, Koh S. Advances in Contact Lens Care Solutions: PVP-I Disinfectant and HAD Wetting Agents From Japan. Eye Contact Lens. 2024 Feb 1;50:91-101.
7. Yasir M, Kumar Vijay A, Willcox M. Antiviral effect of multipurpose contact lens disinfecting solutions against coronavirus. Cont Lens Anterior Eye. 2022 Oct;45:101513.
8. Yasir M, Kumar Vijay A, Willcox M. Antiviral effect of multipurpose contact lens disinfecting solutions against coronavirus. Cont Lens Anterior Eye. 2021 Aug 27:101513.
9. Yamasaki K, Mizuno Y, Kitamura Y, et al. The antimicrobial activity of multipurpose disinfecting solutions in the presence of different organic soils. Eye Contact Lens 2020;46:201-207.
10. Willcox M, Keir N, Maseedupally V, et al. CLEAR - Contact lens wettability, cleaning, disinfection and interactions with tears. Cont Lens Anterior Eye. 2021 Apr;44:157-191.
11. Yamasaki K, Mizuno Y, Kitamura Y, McCanna DJ, Ngo W, Jones LW. The efficacy of povidone-iodine, hydrogen peroxide and a chemical multipurpose contact lens care system against Pseudomonas aeruginosa on various lens case surfaces. Cont Lens Anterior Eye. 2021 Feb;44:18-23.
