Rub and rinse is the proven standard for proper cleaning and disinfecting of contact lenses, and the no rub approach should be eliminated, an FDA panel concluded. The panel also dismissed a proposal to incorporate two-hour staining testing (Andrasko), due to lack of substantive data about the methodology.
These are additional recommendations that came from the FDA Ophthalmic Devices Panel, which met on June 10 to address safety and compliance issues related to the incidence of Acanthamoeba and Fusarium keratitis.
Evidence presented to the panel shows that failure to use a manual cleaning-disinfection procedure (rub and rinse) as well as poor contact lens storage case hygiene may help explain the increased incidence of Fusarium keratitis. 1 One study also suggested that failure to rub lenses as part of the lens care regimen explains the increased incidence in fungal keratitis among contact lens wearers. 2 Another study tied an Acanthameoba outbreak in the Chicago area to solution re-use, lack of rubbing and infrequent case replacement as well as changes in the water supply. 3
Panel members agreed that rubbing and rinsing should be included on product labeling, but they could not agree on a set amount of time required for the rubbing portion.
I think that if rubbing gives you one log unit [of reduction of microbes], its worth it, William D. Mathers, M.D., told the committee. And, it doesnt mean that you cant have an effective solution that gives you more log units, but an additional log unit of efficacy is worth it for a rub.
The quick summary is that rinsing works somewhat; rubbing works even better. The combination of the two is best of all, and not doing either is worst of all, added Timothy McMahon, O.D.
Dr. McMahon recommended that the panel encourage rubbing and rinsing contact lenses and eliminate the no rub approach. However, he said, the no rub approach could be reinstated in the future if a solution meets certain standards as far as micro-efficacy.
The American Optometric Associations Contact Lens and Cornea Section already advises patients to rub lenses for enhanced cleaning even when using a solution with no rub labeling.
The FDA panel also rejected a proposal to incorporate an additional follow-up visit at two hours in order to assess for solution-related corneal staining. This was another reason to reinforce why we shouldnt try to make correlations between the staining and a products performance, said Loretta Szczotka-Flynn, O.D., M.S.
My take on it was there wasnt a lot of correlation with corneal staining and subsequent understanding of these problems from contact lenses, Dr. Mathers said. So, I think the links havent been established correctly, or solidly, and therefore making a recommendation for two hours is not valid at this point.
Further, what practitioners observe might not be actual staining of the cornea. What we may be seeing is basically the preservative somehow binding to this mucin, said Dr. Szczotka-Flynn.
1. Butcko V, McMahon TT, Joslin CE, Jones L. Microbial keratitis and the role of rub and rinsing. Eye Contact Lens 2007 Nov;33(6 Pt 2):421-5.
2. Ahearn DG, Simmons RB, Zhang S, et al. Attachment to and penetration of conventional and silicone hydrogel contact lenses by Fusarium solani and Ulocladium sp. in vitro. Cornea 2007 Aug;26(7):831-9.
3. Joslin CE, Tu EY, Shoff ME, et.al. The association of contact lens solution use and Acanthamoeba keratitis. Am J Ophthalmol 2 007 Aug;144(2):169-80.