contact lens care
In-Office Disinfection of Contact Lenses
BY SUSAN J. GROMACKI, OD, MS, FAAO
We all know how to instruct patients on contact lens disinfection, but are we properly disinfecting the trial lenses we place on their eyes? In this column, I will summarize the recommendations of the Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), the American Optometric Association (AOA), as well as various contact lens textbooks. This will help you establish an in-office protocol that is both safe for your patients and uncomplicated for you and your staff.
The CDC has established standards of care to prevent transmission of the HIV virus through the tears (1985). Before addressing contact lens disinfection, the document emphasized the importance of hand washing and using disposable latex gloves if cuts or open wounds are present on the hands. It then specifies that all instruments that come in direct contact with the external surfaces of the eye or bodily secretions should be wiped clean and then disinfected with a five to 10 minute exposure to one of the following:
- A fresh solution of 3% hydrogen peroxide
- A fresh solution containing 5,000 parts per million free available chlorine
- A 1/10 dilution of common household bleach
- 70% ethanol
- 70% isopropanol
The devices should then be dried before reuse.
To date, there are no documented cases of HIV transmission through tears or contact lenses; the CDC has not included tears on its list of body fluids that are classified as "potentially infectious." For soft lenses, the best mode of precaution is discarding trial lenses, especially with a known HIV positive patient. For PMMA, gas permeable and non-disposable soft contact lenses, the CDC instructs practitioners to use a 3 percent hydrogen peroxide contact lens disinfection system that has been approved for soft contact lenses. Non-contact lens-approved hydrogen peroxide has not been tested and may contain preservatives that discolor soft lenses.
Heat is the only in-office disinfection system approved by the FDA. As a result, the CDC also recommends heat disinfection for low water content hydrogels and PMMA contact lenses. It notes that high water content soft lenses cannot routinely undergo heat disinfection, and GPs may warp. The AOA has accepted the CDC's disinfection policies as its own.
In my practice, after washing our hands, we digitally rub all non-disposable trial soft contact lenses with a surfactant daily cleaner, rinse with saline, disinfect with one of the hydrogen peroxide systems and transfer the lenses to vials containing a multi-purpose solution approved for 30 days of soaking. Neutralized hydrogen peroxide is non-preserved and should not be used for long-term storage. We digitally rub GPs with Boston Laboratory Cleaner (Bausch & Lomb) and rinse with saline. We disinfect with hydrogen peroxide and store the lenses dry. Most studies show that microorganisms are less likely to adhere to dry lenses.
Vinita Henry, OD, makes two excellent points in The Clinical Manual of Contact Lenses. One, trial lenses should be re-disinfected at least once a month to prevent contamination. Second , vial stoppers (especially if placed on the counter or dropped on the floor) are a potential source of contamination. To disinfect the stopper, turn the vial upside down to allow contact with the chemical disinfecting solution.
Dr. Gromacki has a specialty contact lens practice as part of a multi-subspecialty ophthalmology group in Fishkill, NY, and has served as a faculty member at the University of Michigan Department of Ophthalmology and Visual Sciences.