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Samarawickrama C, Li YC, Carnt N, et al. Reducing oral contamination during corneal scrapes. BMJ Open Ophthalmol. 2017;1(1):e000044doi: 10.1136/bmjophth-2016-000044.
Samarawickrama, C., Li, Y. C., Carnt, N., Willcox, M., Dutta, D., & Watson, S. (2017). Reducing oral contamination during corneal scrapes. BMJ open ophthalmology, 1(1), e000044. https://doi.org/10.1136/bmjophth-2016-000044
Samarawickrama, Chameen, et al. "Reducing oral contamination during corneal scrapes." BMJ open ophthalmology vol. 1,1 (2017): e000044. doi: https://doi.org/10.1136/bmjophth-2016-000044
Samarawickrama C, Li YC, Carnt N, Willcox M, Dutta D, Watson S. Reducing oral contamination during corneal scrapes. BMJ Open Ophthalmol. 2017 Feb 25;1(1):e000044. doi: 10.1136/bmjophth-2016-000044. eCollection 2017. PMID: 29354701; PMCID: PMC5721650.
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BMJ Open Ophthalmol. 2017 Feb 25;1(1):e000044. doi: 10.1136/bmjophth-2016-000044. eCollection 2017.

Reducing oral contamination during corneal scrapes.

BMJ open ophthalmology

Chameen Samarawickrama, Yi-Chiao Li, Nicole Carnt, Mark Willcox, Debarun Dutta, Stephanie Watson

Affiliations

  1. Save Sight Institute, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia.
  2. Corneal Unit, Sydney Eye Hospital, Sydney, New South Wales, Australia.
  3. School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia.

PMID: 29354701 PMCID: PMC5721650 DOI: 10.1136/bmjophth-2016-000044

Abstract

AIMS: To identify potential contaminants of the corneal sampling procedure and examine the effect of wearing surgical face masks on the rate of contamination.

METHODS: Ten surgeons recited out loud a 30 s standardised script for corneal scraping with blood agar plates positioned 30 cm away from them. Three groups were identified: in group 1 a surgical mask was worn; group 2 had no mask worn; and group 3 had no mask but used agar plates pretreated with 5% povidone-iodine as a negative control. Each surgeon repeated the process 10 times for all groups, totalling 30 plates per surgeon and 300 plates for the experiment. All plates were masked and incubated aerobically at 37°C for 24 hours, and the number of colony forming units (CFUs) was determined.

RESULTS: At 24 hours, group 1 had a mean of 0.3 CFUs per surgeon; group 2 had 6.4 CFUs per surgeon and group 3 had 0.1 CFUs per surgeon. The difference between group 1 and group 2 was significant (p<0.001) whereas the difference between group 1 and group 3 was non-significant (p=0.4). Use of face masks decreased the number of plates with CFUs by 93% (from 29 to 2 plates) and decreased the total number of CFUs by 95% (from 63 to 3 CFUs). The most common microbiota identified was

CONCLUSIONS: Oral bacterial microbiota may contaminate the slides and media used to collect samples during corneal sampling. Use of a face mask can significantly decrease the rate of contamination of such samples.

Keywords: contamination; corneal scrape

Conflict of interest statement

Competing interests: None declared.

References

  1. Eye (Lond). 2012 Feb;26(2):185-93 - PubMed
  2. Br J Ophthalmol. 2000 Jul;84(7):687-91 - PubMed
  3. Exp Eye Res. 2013 Dec;117:99-105 - PubMed
  4. Br J Ophthalmol. 2011 Jun;95(6):762-7 - PubMed
  5. J Med Assoc Thai. 2012 Apr;95 Suppl 4:S8-17 - PubMed
  6. Open Ophthalmol J. 2012;6:110-24 - PubMed
  7. Optom Vis Sci. 2009 Apr;86(4):312-7 - PubMed
  8. Optom Vis Sci. 2014 Jan;91(1):13-23 - PubMed
  9. J Ophthalmol. 2015;2015:769436 - PubMed
  10. Br J Ophthalmol. 1995 Aug;79(8):777-86 - PubMed
  11. Indian J Ophthalmol. 2009 Jul-Aug;57(4):273-9 - PubMed
  12. Eye (Lond). 2009 Jan;23(1):153-60 - PubMed
  13. Biomed Res Int. 2013;2013:181564 - PubMed
  14. J Clin Microbiol. 2003 Jul;41(7):3192-7 - PubMed
  15. Br J Ophthalmol. 2003 Sep;87(9):1103-8 - PubMed
  16. Br J Ophthalmol. 2015 Nov;99(11):1498-502 - PubMed
  17. Sultan Qaboos Univ Med J. 2009 Aug;9(2):184-95 - PubMed
  18. Retina. 2012 Mar;32(3):473-6 - PubMed
  19. Bull World Health Organ. 2001;79(3):214-21 - PubMed

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