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New Cleaning System for Heavy Depositors Frequent
replacement soft contact lens systems have dramatically reduced many of the
complications seen with traditional yearly replacement lenses. Despite this,
some patients still experience problems with surface deposition. This is borne
out in electron microscopy studies by Fowler et al. which show that a variety
of deposits attach to the surfaces of hydrogel lenses in as little as eight
hours.
To reduce surface contamination, manufacturers have developed new lens care
systems and deposit-resistant polymers, while practitioners have emphasized
patient education, and have prescribed frequent lens replacement systems more
often.
THE FRUSTRATIONS OF A COMPLIANT PATIENT
This month's case history involves a 32-year-old woman with a
seven-year history of daily wear, custom toric soft contact lenses. Her present
lenses are OD +5.25 -3.75 x 005; OS +4.75 -3.50 x 170, and are manufactured in
a methafilcon A, 55 percent water material. The patient wears her lenses 14
hours a day and her visual acuity is stable at 20/30 OU. She disinfects her
lenses nightly with a preservative-free hydrogen peroxide system. Despite
diligent surfactant and enzymatic cleaning, new lenses were significantly
spoiled within two to three months (Fig. 1).
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We recommended that the patient try The Cleaner Accessory (Eaton Medicals
Corp., Memphis), a weekly disposable foam pad designed to enhance the nightly
digital cleaning process (Fig. 2). After wetting the pad with preservative-free
saline followed by six to eight drops of daily cleaning solution, the patient
places a lens on the tip of the thumb or index finger and rubs it on the pad
for 20 seconds, then rinses the lens thoroughly with saline and disinfects.
FIG. 1: Patient's Right Lens After Three Months of
Daily Wear
FIG 3: Sem 500x Anterior Lens Surface After One Month of In-The-Palm Cleaning
THE 30-DAY CHALLENGE
To test the efficacy of the cleaning pad, we ordered two identical
lenses for the patient's right eye. Figure 3 illustrates scanning electron
microscopy results on the anterior lens surface after one month of daily wear
with a traditional in-the-palm cleaning technique.
Figure 4 shows the second lens after one month of daily wear with
nightly use of The Cleaner Accessory pad.
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In both cases, the patient used
the same preservative-free hydrogen peroxide system for nightly disinfection
with weekly enzyme cleaning This case illustrates the potential of an auxiliary
cleaning pad to augment a patient's cleaning regimen. We have found this system
to be helpful in deposit-prone individuals wearing custom soft contact lenses
with parameters outside the ranges of present daily disposable or frequent
replacement systems. The cleaning pad has also been helpful for individuals
prone to surface deposition between frequent replacement schedules. CLS
FIG. 2: The Cleaner Accessory Pad
(Eaton Medicals Corp.)
FIG. 4: Sem 500x Anterior Lens Surface After One Month of Foam Pad Cleaning.
Dr. Campbell is medical director of the Park Nicollet Contact Lens
Clinic & Research Center, Minnetonka, Minn. Patrick Caroline is an
assistant professor of optometry at Pacific University, Forest Grove, Ore., and
director of contact lens research at Oregon Health Sciences University in
Portland.
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