Contact Lens Care & Compliance
Using Enzymatic Cleaners
BY ANDREW D. PUCKER, OD, MS, FAAO
With the advent of the daily disposable contact lenses, the need to remove firmly adhered deposits has lessened because we can simply discard soiled lenses on a daily basis. Nevertheless, some contact lens wearers are not good candidates for daily disposable lenses, and they need to be fit into daily wear soft lenses or specialty lenses. While traditional cleaning agents such as multipurpose lens care solutions typically work well for these modalities (Rosenthal et al, 2003), they may still leave behind deposits that could lead to decreased comfort or even cause chronic conditions such as papillary conjunctivitis (Korb et al, 1983; Nilsson and Lindh, 1988). When standard cleaning systems are not getting the job done, you might want to consider supplementing your patients’ cleaning regimen with an enzymatic contact lens cleaner.
How the Cleaners Are Used
Enzymatic contact lens cleaners are typically used on a weekly basis (Nilsson and Lindh, 1988). While there is limited literature on recent contact lens materials, enzymatic cleaners historically have been effective at removing deposits from both soft and rigid contact lenses (Korb et al, 1983; Begley et al, 1990). Formulations and cleaning procedures vary from product to product, yet enzymatic cleaners are typically used in conjunction with a patient’s typical lens care system (Nilsson and Lindh, 1988).
After application, the enzymes are allowed to work for a few hours. Then, the contact lenses are removed from the solution, rinsed to remove the cleaner, and then used as normally directed.
Three of the most commonly used cleaning enzymes are papain, pancreatin, and subtilisin (Nilsson and Lindh, 1988; Begley et al, 1990). Papain (isolated from papaya plant) and subtilisin (isolated from Bacillus licheniformis) primarily degrade proteins, while pancreatin (isolated from the pancreas of a pig or cow) is able to degrade proteins, lipids, and mucins (Nilsson and Lindh, 1988; Begley, 1990). While these enzymes target different biomolecules, they perform roughly equally at removing contact lens deposits (Begley et al, 1990).
Enzymatic cleaners may improve visual acuity (Lowther, 1977), and they are able to improve contact lens wear time and comfort (Korb et al, 1983; Nilsson and Lindh, 1988). In addition, their effectiveness is dependent upon how deposits are distributed over the contact lens (e.g., poor effectiveness against internally bound deposits) (Lowther, 1977). Furthermore, tear breakup time may increase over enzymatically cleaned contact lenses (Nilsson and Lindh, 1988).
Enzymatic cleaners are able to reduce the number of bacteria adhered to contact lenses (Stern and Zam, 1987). And, they may improve contact lens-associated papillary conjunctivitis symptoms (Korb et al, 1983).
Also of note: Papain-based cleaners have been associated with mild ocular allergic reactions, while pancreatin and subtilisin cleaners are not associated with allergic responses (Barton et al, 1988; Bernstein et al, 1984).
With the increased popularity of scleral contact lenses (Bennett, 2015), enzymatic cleaners may have a new place in modern eye care; they may serve as a much-needed cleaning supplement to maximize the life of these lenses, while allowing for improved comfort and clearer vision (Lowther, 1977; Korb et al, 1983; Nilsson and Lindh, 1988). Therefore, when you are struggling to maintain good comfort and vision with a previously well-fit specialty contact lens, you might also want to consider your patients’ contact lens care plan before you refit them into a different contact lens; this approach could save both you and your patients time and money. CLS
For references, please visit www.clspectrum.com/references and click on document #244.
Dr. Pucker earned his OD and MS degrees from The Ohio State University. He is currently a senior research associate at The Ohio State University. He has also received research funding from Johnson & Johnson Vision Care. You can reach him at firstname.lastname@example.org.