Australian researchers have reported that daily cleaning of contact lenses with a multipurpose disinfection solution (MPDS) did not significantly reduce ocular adverse events with extended wear, however they found daily cleaning did reduce significant corneal infiltrative events.
In a study published in Optometry & Vision Science research optometrist Jerome Ozkan from the Brien Holden Vision Institute and colleagues wrote: “Practitioners should advise patients that without sufficient exposure to MPDS (as recommended by manufacturers), lenses are not likely to be properly disinfected. Although the eye has robust defenses against pathogens, bacteria appear able to exploit the presence of contact lenses. Although there is a reduced risk of complications with daily lens wear compared with overnight wear, without development of lens surfaces that resist bacterial adhesion/colonisation throughout the lens wear period, the occurrence of inflammatory and infectious adverse events will remain an ongoing concern.”
One-hundred-ninety-three people participated in the prospective, randomised, parallel-group, controlled, open-label clinical study over three months which aimed to evaluate the efficacy of MPDS on extended wear. All participants wore Night & Day lotrafilcon A silicone hydrogel lenses, supplied by Alcon, on a 30-day extended-wear schedule.
Participants were divided into two groups. Control group participants were required to wear their lenses for 30 days without removing them unless they experienced irritation. Test group participants were required to remove their lenses each day after waking, and clean them with Biotrue (polyaminopropyl biguanide 0.00013 per cent and polyquaternium 0.0001 per cent, Bausch +Lomb). Contact lenses were then reinserted.
Lens contamination related to handling was measured at the baseline visit and at follow-up visits after one week, one month and three months.
Results showed no significant difference in mechanical events, significant corneal infiltrative events or total corneal infiltrative events between the two groups.
In their report, the authors wrote: “Although the intervention of daily cleaning of the lens surface with an MPDS during extended wear did not significantly reduce inflammatory adverse events, a 74 per cent reduction in significant corneal infiltrative events was observed in the daily lens cleaning (test) group… Brief cleaning of lenses with an MPDS did not significantly impact lens or finger contamination before lens insertion.”
The research was funded by the Australian Federal Government through the Cooperative Research Centres scheme.