Contact Lens Care & Compliance
In-Office Care and Disinfection of Diagnostic GP Lenses
By Michael A. Ward, MMSc, FAAO
I previously addressed this topic in Contact Lens Spectrum columns in September 2006 and November 2009. However, because of recent inquiries by GP lens manufacturers and practitioners regarding proper disinfection and storage of GP diagnostic contact lens sets, I have updated previous articles to address this very important subject.
GP diagnostic lens sets will last for years with proper care and storage. Some trial lens sets will receive regular use, while others may be used only rarely. Regardless of their frequency of use, diagnostic lens sets must be properly cleaned, disinfected, and maintained to ensure parameter accuracy and safety.
Regularly Check Parameters
Unlike soft lenses, GP contact lens parameters can be accurately measured with standard office instrumentation. A magnifying loupe may be used to inspect contact lens surfaces for scratches and debris and to verify optic zone and overall lens diameters. A lensometer can be used to check GP lens power (for high powers, front versus back vertex becomes important) and optical quality. A radiuscope can accurately measure the base curves of spherical and toric lenses as well as detect any lens warpage or posterior surface lens deposits. However, one thing these instruments can't tell us is whether the contact lens surfaces are free from microbial contamination.
Periodically inspect all GP diagnostic lenses to ensure that each is in its correctly labeled container and that the parameters haven't altered over time; replace lenses as necessary.
Preventing Microbial Contamination
Diagnostic GP contact lenses are best stored dry. If GP lenses are stored wet in conditioning/disinfecting solution, they will require regular maintenance to ensure an aseptic state. No contact lens disinfecting solution is approved for lens storage for greater than 30 days. Diagnostic lenses (and storage cases) must be re-cleaned and disinfected at least every 30 days if stored in a wet state. Solution evaporation, drying film formation, and chemical aging may alter the composition of the storage solution, which can compromise its antimicrobial efficacy.
All diagnostic contact lenses must be cleaned and disinfected prior to their reuse. The Centers for Disease Control and Prevention recommends using ophthalmic grade 3% hydrogen peroxide for disinfection of rigid diagnostic lenses. Specifically, “Contact lenses used in trial fittings should be disinfected after each fitting by using a hydrogen peroxide contact lens disinfecting system for 10 minutes.” The two primary peroxide systems available in the United States are Clear Care (Ciba Vision) and Oxysept UltraCare Formula (Abbott Medical Optics).
Diagnostic GP Lens Care Recommendations
Clean GP diagnostic contact lenses after each use with a surfactant cleaner such as Boston Advance Cleaner (Bausch + Lomb), Optimum Extra Strength Cleaner (Lobob Laboratories), or Extra Strength Daily Cleaner (Walgreens, CVS) after each use and rinse thoroughly.
Disinfect the lenses with an approved peroxide system (Clear Care or Oxysept) for a minimum of 10 minutes; rinse and dry.
Store rigid diagnostic lenses dry for long-term storage.
Prior to reuse, clean the diagnostic lenses with an approved cleaner, then rinse and wet them with an appropriate wetting or conditioning solution. CLS
To obtain references for this article, please visit http://www.clspectrum.com/references.asp and click on document #190.
Mr. Ward is an instructor in ophthalmology at Emory University School of Medicine and Director, Emory Contact Lens Service. You can reach him at email@example.com.