PhD defense : Interventional Magnetic Resonance Elastography dedicated to the monitoring of percutaneous thermal ablations

PhD defense : Nadège CORBIN

Team : AVR

Title : Interventional Magnetic Resonance Elastography dedicated to the monitoring of percutaneous thermal ablations

Abstract : Percutaneous thermal ablations have emerged as an efficient alternative to open-surgery for the destruction of cancerous tissue while minimizing the complication rate. Magnetic Resonance Imaging (MRI) is appreciated to monitor these minimally-invasive procedures, especially because the temperature of the ablated region can be measured in real-time. Nevertheless, no information related to structural properties of the tissue is available during the procedure. The possibility of measuring mechanical properties by Magnetic Resonance Elastography (MRE ) has already been clearly demonstrated but the current systems do not meet the demanding conditions of interventional MRI in terms of bulk and update rate. The objective of this doctoral work is therefore to develop interventioanl MRE dedicated to the monitoring of percutaneous thermal ablations. The designed system is composed of a needle MRE driver that generates waves directly within the region of interest, a fast and interactive MR pulse sequence that encodes the motion on MR phase images and an inverse problem solver that reconstructs elasticity maps in real-time. Thanks to this interventional MRE system, the temporal evolution of elasticity and temperature induced by thermal ablations were successfully observed in real-time. An innovative method for MRE data processing was also proposed in order to avoid challenging steps of the conventional process. This alternative consists in obtaining elasticity information without reconstructing any phase image. Promising results obtained in phantoms and in vivo have demonstrated the relevance and the feasibility of the method.

The presentation will take place on Monday 14th December 2015 at 1.30pm at the IRCAD building in Strasbourg. This thesis will be supported in english.