In vitro antimicrobial efficacy of riboflavin, ultraviolet-A radiation, and combined riboflavin/ultraviolet-A radiation on ocular pathogens

Abstract

PURPOSE: There is a lack of studies evaluating the antimicrobial effect of riboflavin and ultraviolet-A (UVA) radiation using an epithelium-off cross-linking technique (Dresden protocol) in the literature. This study aimed to demonstrate the antimicrobial properties of riboflavin and UVA radiation and combined riboflavin/UVA radiation on various ocular pathogens Dresden protocol. MATERIALS AND METHODS: This was a prospective and comparative study. This study included four groups: Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Acanthamoeba . All the groups were tested 12 different times with riboflavin alone, UVA light alone, and combined riboflavin with UVA. The growth inhibition zones were measured. Descriptive statistics were expressed as mean and standard deviation. The main outcome was measurement and analysis of growth inhibition zones. RESULTS: The mean growth inhibition zones following riboflavin and UVA exposure were 9.70 ± 1.63 mm for P. aeruginosa and 7.70 ± 1.08 mm for S . aureus . The mean growth inhibition zones for P. aeruginosa were greater than for S . aureus (t = 2.395, P = 0.038). The mean growth inhibition zones for C. albicans and Acanthamoeba were 0. The mean growth inhibition zones following UVA exposure alone and riboflavin alone for all organisms were also 0. CONCLUSION: Combined riboflavin and UVA in the clinical dose was effective against P. aeruginosa and S . aureus but ineffective against C. albicans and Acanthamoeba . Our study shows the potential of combined riboflavin and UVA in the treatment of bacterial keratitis.

Advancing beyond our recent advances in ocular surface disease and corneal surgery

“…'s[ 7 ] paper on establishing a new dry eye model in rabbits is very relevant and will set the stage for future studies that will advance our understanding of this common condition. Furthermore, continued studies on the in vitro antimicrobial efficacy of riboflavin and ultraviolet radiation on ocular pathogens, as reported by Sharma et al .,[ 8 ] provide further insights into its appropriateness for use in patients with specific types of infectious conditions of the cornea. The study also suggests to us for which patients we should not use this procedure.…”