Abstract

Purpose: Commercial eyewash solutions are widely used in Japan for the removal of foreign bodies from the ocular surface and relief from unpleasant symptoms, and many individuals use them daily. However, the effects of habitual eye washing on the conjunctival bacterial flora have not been investigated yet. In this study, the bacterial flora in healthy eyes was evaluated after one month of continuous use of a commercial eyewash solution.

Methods: In total, 29 participants with healthy eyes were recruited. Eyebon^® W, a commercial eyewash solution available in Japan, was used as the test eyewash. The eyes were randomly designated as treatment (group 1) and no treatment (group 2). The eyes in group 1 were washed twice daily with Eyebon^® W for one month. The eyes in group 2 were not treated with any eyewashes or eye drops. Samples were collected from the inferior palpebral conjunctiva. Ultimately, a sufficient amount of cDNA for analysis was obtained from 11 individuals (22 eyes). The viable bacterial count was determined and the bacterial flora was analyzed using next-generation sequencing of 16S rRNA amplicons.

Results: In both groups, the bacterial flora was mainly composed of 6–7 genera. There were no statistically significant differences in the average rates for each genus in the conjunctival bacterial flora, regardless of the eyewash condition (P > 0.05).

Conclusion: Our findings suggest that washing eyes twice a day using eyewash is unlikely to have a significant impact on the conjunctival bacterial flora.

Conclusion: Eyebon®; Eyewash; Ocular Surface; Microbial Flora; Safety; Long Time-use

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Citation

Citation: Takafumi Saeki., et al. “Long-term Effects of Eyewash Solution Use on the Conjunctival Bacterial Flora”.Acta Scientific Ophthalmology 4.1 (2021): 27-42.

Copyright

Copyright: © 2021 Takafumi Saeki., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.