Laser-Generated Shockwaves as a Treatment to Reduce Bacterial Load and Disrupt Biofilm

Abstract

Objective: The goal of this paper is to demonstrate and evaluate the potential efficacy of laser-generated shockwave (LGS) therapy on biofilm infected tissue. Methods: To demonstrate proof of concept, Staphylococcus epidermidis was allowed to proliferate on ex vivo pigskin, until mature biofilm formation was achieved, and then subjected to LGS. Bacterial load between control and treated samples was compared using the swab technique and colony counting. Scanning electron microscopy (SEM) was then used to visualize the biofilm growth and resulting reduction in biofilm coverage from treatment. Images were false colored to improve contrast of biofilm, and percent biofilm coverage was computed, along with biofilm cluster size. Results: LGS reduced bacterial load by 69% (p = 0.008). Imaging showed biofilm coverage reduced by 52% and significantly reduced average cluster size (p < 0.001). Conclusion: LGS therapy reduced the burden of bacterial biofilm on ex vivo pigskin and can be visualized using SEM imaging. Significance: LGS therapy is a new treatment for infected wounds, allowing rapid disruption of biofilm to 1) remove bacteria and 2) increase susceptibility of remaining biofilm to topical antibiotics. This can lead to improved wound healing times, reduced patient morbidity, and decreased healthcare costs.

Sensitizing bacterial cells to antibiotics by shape recovery triggered biofilm dispersion

“…Eradicating established biofilms remains challenging. Previous research on biofilm removal has been largely based on the use of forces generated by air bubble [62,63], shock wave [64,65], water jet [66], acoustic energy [67], and magnetically rotating microrods [68,69]. These conditions can be harsh and require additional equipment, which may hinder in vivo applications.…”

Chronic tonsillitis and biofilms: a brief overview of treatment modalities

“…Such interventions will promote patients’ quality of life by reducing healing times and morbidity, and save health care costs. 136 …”

Laser-generated shockwaves enhance antibacterial activity against biofilmsin vitro

“…Similarly, an increase in gentamicin susceptibility was also observed, when the samples were first treated with LGS. A possible mechanism for this is that, since LGS therapy can fragment the biofilm as previously seen in scanning electron microscopy studies , this increased permeability may allow antibiotics to reach the bacteria more effectively. There may also be a second mechanism, where LGS can disrupt the cell wall, increasing its permeability to gentamicin.…”

“…Early work by Krespi et al and Nigri et al strongly suggested the efficacy of LGS in disrupting biofilms in vitro , while Doukas et al expanded on this research by showing that LGS increased transdermal drug delivery by affecting surface permeability . Our group has further expanded on LGS applications in infected wounds in in vitro models , and is currently underway in translating this concept to in vivo studies. However, the ability of LGS to remove biofilm has not been directly quantified.…”