Image Guided Interventions Laboratory
Minimally invasive interventional techniques, in particular in the field of oncology, aim of minimizing damage of the healthy tissue that surrounds the pathology being treated and the systemic side effects. Intra-operative image guidance is a specialized area of medical imaging with particular robustness and real time requirements. High intensity focused ultrasound (HIFU) is currently the only extra-corporeal technology capable of depositing sharply delineated energy patterns deep inside the body, with a demonstrated potential for achieving thermal ablation of pathological tissue. Magnetic resonance imaging (MRI) offers excellent anatomic delineation of tumors and is capable of measuring functional changes such as blood flow alteration. Furthermore, MRI provides excellent capabilities for spatial guidance and on line therapy control, and is currently the only available technique for non-invasive temperature measurement within biological tissue.
Treatments using HIFU in the abdominal region remain challenging due to respiratory organ motion. We demonstrated in vivo a truly hybrid US-MRI guided HIFU method to plan and control inter-costal treatment in real time, based on prospective full three-dimensional motion-compensation with dynamic HIFU beam forming, MR thermometry slice following and reference-less PRFS MR thermometry. As a result, static-like elementary HIFU lesions were generated despite motion. Our longer term goal is to perform clinical trials using the MRgHIFU technology applied to neoplastic nodules in the liver (primary and secondary tumors) and also in the pancreas.
In order to enhance the therapeutic effects of ultrasound, thereby reducing the risk of side effects, we are participating in an international network which aims to develop nanotechnology that allows a targeted delivery and the controlled induction of cytotoxicity using sonosensitizers. Multi-nucleus MRI (19F, 129Xe) will be used to monitor the process. Dedicated NMR coils are under development for this purpose and have been designed such as to be integrated into the interventional environment.