Meeting Banner
Abstract #4041

MR-ARFI for the Quantification of Tissue Elastic Properties

Tetiana Dadakova 1 , Ali Caglar zen 1 , Axel Joachim Krafft 1 , Jurgen Ftterer 2 , Martijn Hoogenboom 2 , Jrgen Walter Jenne 3 , Erik Dumont 4 , Christakis Damianou 5 , Jan Gerrit Korvink 6 , and Michael Bock 1

1 Department of Radiology - Medical Physics, University Medical Center Freiburg, Freiburg, Germany, 2 Department of Radiology and Nuclear medicine, Radboud University Medical Center, Nijmegen, Netherlands, 3 Fraunhofer MEVIS, Bremen, Germany, 4 Image Guided Therapy, Pessac, France, 5 Department of Electrical Engineering, Computer Engineering and Informatics, Cyprus University of Technology, Limassol, Cyprus, 6 Department of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany

High intensity focused ultrasound (HIFU) under MR guidance allows for pre-treatment planning, post-treatment assessment and real-time temperature monitoring during treatment in ablative hyperthermia of tumors. In addition to heating, HIFU causes micrometer transient displacements in the tissue, which is most pronounced at the focal spot. The displacement can be visualized with MRI (acoustic radiation force imaging, ARFI) using motion encoding gradients. The time-dependency of the displacement can be described by an overdamped harmonic oscillator model, which has two parameters: the maximum tissue displacement ∆x, and the rise time τ. The rise time is related to the mechanical tissue properties, and its quantification is needed for modelling of the tissue response during ARFI, and to distinguish tissues based on their stiffness. In this work we developed a method to quantify τ from MR-ARFI data. To assess whether tissue stiffness changes with heating, τ was calculated in 4 regions of a porcine muscle ex vivo phantom, which received different thermal doses.

This abstract and the presentation materials are available to members only; a login is required.

Join Here