the contact lens exam
Deep Clean GP Lenses for Improved Comfort and Vision
BY JOHN MARK JACKSON, OD, MS, FAAO
Clean lenses are comfortable lenses. We see this every day in our practices as patients marvel at how comfortable their new trial lenses feel compared to their old, dirty lenses. It�s also a major reason why we use disposable soft lenses. Even with the best of intentions and habits, lenses will have deposits that patients can't remove. I usually use dentistry as an analogy with patients: no matter how well they brush and floss, they still need the dentist to deep clean their teeth. For most soft lenses the solution is to throw them out as they soil. GP lenses, however, aren't as inexpensively replaced. Fortunately, they are easy to deep clean in your office.
A Problem With GP Comfort
I recently saw a GP multifocal wearer who complained that her lenses were bothering her; the comfort had declined as well as her acuity. Her right lens was particularly uncomfortable. My initial thought was that it was time to replace the lenses as they were more than two years old.
When I viewed the lenses with the slit lamp, both had protein buildup, visible as a white haze on the surfaces. On the right lens, a dried plug of mucus had formed in the drill-mark (Figure 1). The plug protruded from the lens and had a jagged surface. With lid eversion I noted a localized area of papillary conjunctivitis on the tarsal plate that exhibited mild injection. Although the protein deposits were likely making the lenses less comfortable and decreasing acuity, this mucous plug was the true culprit.
Figure 1. Mucous plug in drill mark of patient's GP lens.
Deep Cleaning the Lenses
To clean her lenses, I used a twostage approach. First, I held the right lens between my fingers and viewed it through the slit lamp. I used a cotton-tipped applicator soaked in Boston Lab Cleaner (Bausch ' Lomb) to swipe the plug until it dislodged. I then soaked the lenses in Menicon Progent for 30 minutes. This system thoroughly cleans deposits from the lens surfaces and disinfects them, too. After soaking, I thoroughly rinsed the lenses with saline and conditioned them with Boston Simplus (B'L). The patient noticed an immediate improvement in comfort and an improvement in acuity as well (from 20/40 to 20/25 at near). I suggested she not wear the lenses for a few days to allow the lid to recover from the irritation of the mucous plug.
Easier and Safer than Polishing
Before Progent was available, the usual method to remove protein deposits from GP lenses was to polish the surfaces with a sponge pad on a lens modification unit. This method has worked well, but it is labor intensive (i.e., usually done by the practitioner) and lenses can be damaged. Ortho-k lenses in particular are very precisely made, and polishing the surfaces could alter the parameters enough to ruin their effectiveness. Progent allows a technician to perform the lens cleaning with little labor or lens risk involved. I now use it almost exclusively for in-office GP cleaning.
While GPs are more deposit resistant and easier to clean than soft lenses are, they still require some extra attention when patients present for exams. A thorough cleaning will keep your GP patients� eyes feeling and seeing well, and patients will appreciate the extra service provided. CLS
Dr. Jackson is an associate professor at Southern College of Optometry where he works in the Cornea and Contact Lens Service, teaches courses in contact lenses, and performs clinical research.