contact lens care
Keeping Clean Cases
BY MICHAEL A. WARD, MMSc, FAAO

Sight-threatening microbial keratitis is the most significant adverse event associated with contact lens wear. Prevention of this and other contact lens-associated infections has been a primary industry goal since the introduction of contact lenses to the eyecare market. The reported incidence of contact lens-associated ulcerative keratitis is approximately four cases for every 10,000 daily wear patients. The incidence is purportedly less for silicone hydrogel lens wearers. How can we make lens wear even safer for patients?

Figure 1. Contact lens-associated Acanthamoeba sp. corneal ulcer.

Know Your Enemies

Fortunately we have an innovative and responsive lens care industry. The incidence of hypersensitivity and toxicity reactions has greatly diminished since chlorhexidine and thimerosal have essentially disappeared from the contact lens market. Today's lens care products are safe, effective and convenient -- when used properly.

Practitioners must do their part in providing proper patient instruction. Simply telling a patient to do something isn't sufficient. Provide patients with a valid reason for each step of your instructions. When patients understand why they should do something a certain way, it reinforces positive behavior. Augment verbal instructions with appropriate care product demonstration and written reference materials.

Patient compliance with lens replacement schedules and care product usage remains a challenge. A study by Jones (2002) indicated that approximately one-half of patients using two-week and one-month soft lenses are noncompliant in their lens replacement schedules.

Practitioners can influence patient compliance by providing simple instructions, reasoning, stressing the importance of proper hygiene and questioning patients at each visit about their lens care and lens replacement practices. Further, avoid fitting contact lenses on patients whose hygiene is questionable and whom you suspect of risky or noncompliant behaviors.

	Figure 2. Contaminated contact lens case.

Streamline Your Instruction

The contact lens storage case is the most likely potential reservoir for contact lens-related infections (Figure 1). Therefore, put case care high on your list of important lens wearing instructions to patients. Your case care instructions should include this advice:

• Don't top off storage solutions in the case
• Empty the lens case after removing lenses and rinse with either fresh solution or hot water
• Leave the lens case open, allowing it to air dry during the day
• Scald the case with freshly boiled water once a week
• Replace the case often

Keep it Safe

Contact lens case care is necessary in preventing the formation of bacterial biofilms in the case wells (Figure 2). Once formed, these biofilms become persistent and protect the bacteria from the disinfecting effects of the storage solutions. Some care products provide a new storage case with each new bottle of solution. Encourage patients to actually use the new cases.

Appropriate product use and proper lens care promote good, safe ocular health for our contact lens wearing patients.

Mr. Ward is an instructor of ophthalmology at Emory University School of Medicine and is director, Emory Contact Lens Service.