Introduction

Diagnostic ultrasound imaging is a common imaging modality and familiar to many as a means to visualize the fetus in utero.  This imaging technique demonstrates a useful feature of ultrasound:  the ability to pass through tissues of the body without disrupting them. However, if the beam of ultrasound is sufficiently powerful and is brought to a focus, energy deposition at the focal point causes the tissues to be heated sufficiently to cause tissue necrosis.  High Intensity Focused Ultrasound (HIFU) or Focused Ultrasound (FUS) can thus be used to ablate unwanted tissue deep within the body without damaging the surrounding healthy tissues.  The challenge is to focus the ultrasound beam on the unwanted tissue and control the ultrasound energy deposition so any damage to the adjacent healthy tissue is minimized.

Magnetic Resonance Imaging (MRI) guidance allows the target region to be visualized allowing for accurate treatment planningand targeting.  In addition, MRI provides a means to measure the change in tissue temperatures in 3D allowing for real-time, accurate monitoring of the target region.

The Focused Ultrasound Group at the University of Utah has several active research interests in Magnetic Resonance Guided Focused Ultrasound (MRgFUS).  We have pioneered technical advancements in focused ultrasound modeling including beam aberration correction, magnetic resonance temperature imaging (MRTI) and magnetic resonance acoustic radiation force imaging (MR-ARFI). We specialize in MRgFUS hardware design and the design of FUS compatible radiofrequency coils that are required in MR imaging.  In collaboration with several clinical colleagues, we are currently using our technical advancements to study using MRgFUS to treat breast cancer, control resistant hypertension through renal denervation, transcranial neuro applications, localized drug delivery and several other applications.