![]() ![]() The contact lenses used in the tests were sterile, non-ionic low water content lenses (Medalist Polymacon, Bausch and Lomb), and high water content ionic contact lenses (Acuvue daily disposable, Johnson and Johnson). It is a small battery operated device which produces incredible turbulence within the lens case, resulting in very thorough cleaning. At the heart of the system is a multidirectional, vibration generating device which is completely new to this field. The device is commercially available and is manufactured by a LensCare Ltd. 10 Efron et al evaluated a standing wave device and an ultrasound unit, 11 with standing wave providing little if any reduction to the micro-organisms tested and ultrasound producing only minimal reduction over a 22 minute period of operation. 9 Therefore, an ideal care system needs to eliminate the qualitative test of “rub and rinse” and substitute a more reliable method for cleaning contact lenses.ĭevices for cleaning lenses that were marketed in the past, were generally found to be limited when tested with normal saline alone. Use of monthly disposable lenses may encourage less diligence in cleaning lenses. 1 7 This indicates that many commercially available lens care systems may not be adequate on their own. 7 8 Levels of microbial contamination of 10 8 cfu/ml and above are common in used contact lens cases. 6ĭaily cleaning of contact lenses is not always properly performed by lens wearers. ![]() The studies show that bacteria can survive chemical disinfection 5 and they describe resistance to hydrogen peroxide by Candida parapsilosis, a yeast associated with cutaneous infections. Studies indicate that several multipurpose solutions and peroxide systems are not able adequately to disinfect concentrations of bacteria (for example, Staphylococcus aureus) of 10 7–10 8 cfu/ml. 4Ĭontact lens wearers and eye care practitioners may rely too much upon contact lens solutions to reduce microbial contamination. 3 Physical cleaning of lenses and lens cases, helps to reduce micro-organisms before chemical disinfection. 2 A contributing factor to lens wear complication is microbial contamination, and reports suggest that up to 95% of lenses in use are contaminated. 1 Lens wearers are increasingly seen in accident and emergency departments of certain hospitals. The incidence of microbial keratitis in contact lens wear appears to be increasing and indications are that up to 30% of corneal ulcers are associated with contact lens wear. ![]()
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