Comparative efficacies of four soft contact lens disinfection solutions

We compared the antimicrobial activity of four soft contact lens disinfection solutions: Opti-One (Alcon), Opti-Free (Alcon), Complete (Allergan), and ReNu (Bausch & Lomb). Opti-One, Complete, and ReNu are multi-purpose solution systems which use a single solution for cleaning, rinsing, and disinfecting. Opti-Free is a rinsing and disinfecting solution designed to be used in conjunction with a daily cleaner. Each solution was tested on two different species of bacteria: Pseudomonas aeruginosa and Staphylococcus epidermidis. Inocula of 10⁸ colony-forming units per milliliter were tested in 9-ml aliquots of each test solution. Samples were taken at 10, 20, 40, 60, 120, and 240 minutes after inoculation, and the surviving bacteria were grown on plate media and enumerated after 48 hours. We found that Opti-Free and Opti-One were more effective than ReNu and Complete against S. epidermidis, and Complete was marginally more effective than the other three solutions against P. aeruginosa. None of the four multipurpose disinfection solutions tested was effective in completely eliminating P. aeruginosa by disinfection alone; therefore, it is important that contact lens wearers always clean and rinse their contact lenses before disinfection.