Therapeutic ultrasound: Surgery and drug delivery

Abstract

The field of therapeutic ultrasound is emerging with strong potential and broad medical applications. Characterized by its ability to penetrate at depth inside the body without harming intervening tissue, ultrasound has posed the basis for a new array of noninvasive therapies. Al low intensities, important interactions occur in the tissue; wound healing is accelerated, functional recovery is enhanced, and bone growth is more rapid. At moderate intensities, cellular membranes show transient permeability, blood clots dissolution is increased, and gene-transfection is accomplished. At higher intensities, ultrasound produces lesions and stops bleeding by heating the tissue beyond its protein denaturalization threshold and thus provides a noninvasive, bloodless alternative to conventional surgery. This article presents a review of moderate and high intensity applications, including their mechanisms of action and the imaging modalities used for guidance and monitoring.