Journal of ophthalmology
Ultraviolet-C Light Emitter as a Method for Reducing Bacterial Contamination of Ophthalmic Instruments
By Velez-Montoya R, Franco-Ramirez KC, Vargas-Fernández AT and 4 others.
Abstract
Background
To assess the efficacy of an ultraviolet light type C (UVC) emitter in reducing bacterial load in common surgical equipment used during in-office ophthalmological procedures.
Methods
We used 7 steam-sterilized lid speculums. The first one was the negative control. The second was left unprotected in a high-traffic area for 24 h before being cultivated. Lid speculums 3 to 7 were contaminated with a strain of Staphylococcus epidermidis, recovered from an active case of postoperative endophthalmitis. The third one was cultivated immediately after contamination. Lid speculums 4 to 7 were exposed to UVC for 30 s, 2, 5, and 10 min, respectively (continuous 254 nm UVC, irradiance > 160 mW/cm2). All speculums were cultivated on Mueller-Hinton agar plates for 48 h (≈21% O2). Differences in bacterial load, observed colonies, and colony-forming units were assessed with a Kruskal-Wallis test. All experiments were done in triplicate.
