Dry eye is a common condition that is treated primarily by topical lubricants, immunomodulation, and a variety of punctal and canalicular plugs (occluders). Biofilm formation has been reported as an ongoing problem with the clinical use of occluders. In order to explore the role of biofilm formation on occluders, we tested the bacteria strain, Staphylococcus aureus, with three different types of occluders, DeltaR, OdysseyR, and AlphamedR. Scanning electron microscopy (SEM) of these occluders revealed a variation in surface appearance, with OdysseyR being the smoothest (but with grooves), followed by DeltaR, and AlphamedR. Exposing each type of occluder to dynamically grown bacterial cultures of S. aureus, a ~3 fold statistically significant difference in bacteria colonization between the OdysseyR and AlphamedR occluder and a ~2 fold higher trend between OdysseyR and DeltaR were detected. These quantitative results were also verified with SEM, showing extensive S. aureus colonization and biofilm formation on the surface of the OdysseyR occluder. The results also indicate that bacterial colonization readily occurs on all three types of occluders. The occluder with the smoothest but grooved surface (OdysseyR), displayed increased biofilm formation when compared to those with rougher surfaces.
Keywords: S. aureus; bacteria; biofilm; dry eye disease; occluders; plugs; punctal.