Abstract
Purpose :
Good compliance with hygiene practices during use of contact lenses may play an important role in reducing microbial contamination of lenses and cases. This study evaluated whether people identified as being deficient in their hygiene practices had higher levels or frequency of contact lens case contamination, and whether the use of a silver-containing contact lens case could help overcome these deficiencies.
Methods :
A prospective, randomized, double-blind, crossover study was conducted using silver or control barrel cases over a two-month period. At each visit, compliance with contact lens hygiene practices was evaluated using a self-administered questionnaire. Contact lens cases were collected, and the frequency and type of microbial contamination evaluated using culture and standard identification methods.
Results :
Forty-eight participants with an average age of 29 ± 13 completed the study. Overall, 13 (27%) silver and 16 (33%) control lens cases (p < 0.005) were contaminated, predominantly with Gram positive bacteria. Approximately, 0.16 (0 - 4.2) and 0.25 (0 – 4.98) Log10 CFU/case of microbes were recovered in silver and control lens cases, respectively (p > 0.05). Upon analysis of the hygiene compliance, only 12% were classified as having good compliance (9 out of 12 correct behaviors), 46% had average compliance (7 out of 12 correct behaviors) and 43% had poor compliance (6 or fewer out of 12 correct behaviors). Approximately, 85% of the participants had good hand hygiene, washing their hands with soap prior lens use. During lens cleaning 69% of lens wearers reported rubbing and rinsing their contact lenses, but only 37% participants reported rubbing their contact lens storage cases after lens removal with the fresh disinfecting solution (p < 0.005). However, no correlation was found between the level of lens case contamination and the compliance scores irrespective of the type of storage cases used.
Conclusions :
Most contact lens wearers in this study were non-compliant with many aspects of contact lens hygiene. Although compliance did not correlate with contamination of lens cases in this study, the use of silver lens cases was associated with lower rate and level of lens case contamination. Therefore it appears that antimicrobial lens cases are more effective at reducing lens case contamination than compliant behaviours.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.