Toward treatment of abscesses using non-thermal HIFU

Abstract

Abscesses are infected walled-off collections of pus and bacteria. They can affect any part of the body. Current treatment is typically limited to antibiotics, catheter drainage and hospitalization, or surgical wash-out when inaccessible, loculated or unresponsive to initial care efforts. Although bacteria can develop drug resistance, they remain susceptible to thermal and mechanical damage. High Intensity Focused Ultrasound (HIFU) generates localized heating and cavitation, and represents a potential new noninvasive treatment modality. This talk describes initial experiments in which non-thermal HIFU treatment was used to inactivate small volumes (100 μL—10 mL) of Escherichia colisuspensions (~1 × 109 cells/mL) with 1 or 2-MHz transducers. Free-field focal acoustic pressures were as high as 16 (9.9) MPa peak positive (negative). Survival was assessed by coliform counting, and by alamarBlue® vital staining. At duty factors of 0.01 or 0.2, and the highest acoustic pressures, there was no biologically signi...