Why Lens Care Matters
Contact lens-related complications -- particularly microbial keratitis -- are significantly reduced by proper lens care and hygiene. The CPOA is a key educator on these practices and must be able to explain the function of different lens care solutions and correct common patient errors. Even a single instance of improper lens care (like rinsing lenses with tap water) can lead to sight-threatening infections.
Types of Contact Lens Solutions
Multipurpose Solutions (MPS)
Multipurpose solutions are the most commonly used lens care system. A single solution cleans, rinses, disinfects, and stores contact lenses. Steps:
- Rub the lens with solution for 20 seconds on each side (digital rubbing improves effectiveness even with "no-rub" labeled products)
- Rinse with fresh solution
- Store in a lens case with fresh solution
- Replace case every 1-3 months
MPS contain preservatives (such as PHMB, alexidine, or polyquad) to kill organisms. Some patients develop preservative sensitivity, causing lens discomfort and redness -- switching to preservative-free hydrogen peroxide systems is often helpful.
💡 Clinical Tip: Instruct patients to always use fresh solution in the lens case. "Topping off" (adding new solution to old) dramatically reduces disinfection efficacy because the preservative concentration drops and biofilm can form. Empty, air-dry, and refill the case completely each time.
Hydrogen Peroxide Systems (H2O2)
Hydrogen peroxide (H2O2) care systems use 3% hydrogen peroxide to disinfect lenses, then neutralize it with a catalytic disc in the case, converting it to water and oxygen. Examples: ClearCare, ClearCare Plus.
Key points:
- Requires a minimum 6-hour neutralization period -- lenses inserted before neutralization is complete will cause severe corneal pain and chemical burn
- No preservatives -- excellent for preservative-sensitive patients and allergy sufferers
- Superior disinfection compared to MPS -- preferred for patients with compliance issues or recurrent infections
- Cannot be used as a rinse or eyedrop -- only in the designated case
⚠️ Common Mistake: Patients sometimes mistakenly use hydrogen peroxide solution as a rinse directly on the lens or eye. This causes immediate, severe pain from chemical corneal injury. Emphasize to patients that H2O2 solutions must ONLY be used in the neutralizing case and never directly on the eye.
Saline Solutions
Sterile saline solution is used to rinse lenses (not disinfect). It is used as a lens bath and for rinsing after enzymatic cleaning. It contains no preservatives or disinfectants and should not be used as a sole storage solution.
Enzymatic Cleaners
Protein deposit buildup on lenses reduces comfort and clarity. Enzymatic cleaners (usually containing protease enzymes) are used weekly or monthly to remove protein deposits from extended-replacement soft lenses. Daily disposables do not need enzymatic cleaning because the lens is discarded before significant deposits accumulate.
Rigid Gas-Permeable (RGP) Solutions
RGP lenses require specific daily cleaner, conditioning solution, and saline for rinsing. They cannot generally be used with soft lens multipurpose solutions (which may damage the material). An RGP wetting/storage solution conditions the lens surface and improves comfort on insertion.
Tap Water: A Major Hazard
Tap water should never contact contact lenses, lens cases, or the lens care system. Tap water can contain Acanthamoeba, a free-living amoeba found in municipal water supplies that causes Acanthamoeba keratitis -- a devastating, treatment-resistant corneal infection that can lead to corneal transplant or permanent vision loss. Patients who shower, swim, or use hot tubs while wearing contacts are at elevated risk.
| Water Source | Risk |
|---|---|
| Tap water | High (Acanthamoeba contamination) |
| Swimming pools | High (chlorine does not kill Acanthamoeba) |
| Ocean / lakes | Very high |
| Hot tubs / spa | Very high |
| Sterile saline | Safe for rinsing |
Lens Case Hygiene
The lens case is a primary source of contamination. Key patient education points:
- Rinse the case with fresh multipurpose solution (not water) after each use
- Allow the case to air dry face-down on a clean tissue
- Replace the case every 1-3 months or with each new bottle of solution
- Never share a lens case
Compliance Issues
Studies consistently show that most contact lens wearers do not fully comply with care instructions. Common non-compliance behaviors:
- Sleeping in lenses not approved for extended wear
- Topping off solution in the case
- Not replacing lenses on schedule (wearing monthlies for 2+ months)
- Using lenses after expiration date
- Swimming or showering in lenses
The CPOA plays a critical role in motivating compliance through patient education and reinforcing safe practices at each visit.
Key Takeaways
- Multipurpose solutions clean, disinfect, rinse, and store; digital rubbing is still recommended even with "no-rub" solutions
- H2O2 systems require a 6-hour neutralization period; placing lenses on the eye before neutralization is complete causes a chemical burn
- Never allow tap water to contact lenses or the lens case -- risk of Acanthamoeba keratitis
- Never top off old solution in the case; always use fresh solution
- Replace lens cases every 1-3 months
- Daily disposable lenses require no care solutions and have the lowest infection risk