As part of the EUROTECH visiting researcher programme, Asst. Prof. Irena Zivkovic was hosted by the CIBM MRI EPFL Animal Imaging and Technology Section from March 15-30, 2023.

This program promotes cooperation between researchers at its partner universities, among which are École polytechnique fédérale de Lausanne – EPFL and Eindhoven University of Technology – TU/e, The Netherlands.

About the visitor

Dr Irena Zivkovic obtained her PhD at the Institute of Applied Physics, University of Bern, Switzerland in 2012. Before obtaining her PhD, she was a research fellow at the California Institute of Technology (Caltech, Pasadena, USA). The topic of her research was applied electromagnetics – in astronomy (until and including her PhD) and in MRI (after obtaining PhD). She was a Max Planck fellow from 2013-2017 at the Max Planck Institute for Biological Cybernetics in Tuebingen, Germany, where she worked on 9.4T human MRI scanner. From 2017-2019 she held postdoctoral position in Radiology department at the Leiden University Medical Center (LUMC), Leiden, the Netherlands, where she worked mostly at 7T MRI but also at ultra-low field (50mT) and at clinical scanners (1.5T and 3T). In 2019, she was appointed as assistant professor in Electrical Engineering department, at the Technical University of Eindhoven, the Netherlands, where she is founder and PI of MRI hardware development reserch line. The main motivation for her work is to exploit full potential of MRI imaging modality across full spectrum of field strengths. Her main research interest is MRI engineering for manipulation of both static (B0) and the RF (B1) fields at both active and passive way. She worked on matrix shim approach for B0 field correction, new RF coils for high performance UHF imaging, implementation of high permittivity dielectric materials, design and implementation of metamaterial inspired structures, building of high performance low field scanners, MR guided interventions, etc.

“It was a very fruitful stay, we are drafting three ESMRMB abstracts and two journal publications (for now)”
Irena Zivkovic
“This is the most productive short-term research visit that I’ve ever seen! Thanks a lot for bringing all this positive energy!”
Dimitri Van De Ville

Visitor's Talk

Title: MRI Engineering – new ideas for maximized performances at the ultra-high and ultra-low field strengths

Abstract: Signal to noise ratio (SNR) is an important parameter which describes the performance of an MRI system. Motivation for moving towards the higher field strengths is increased SNR. One of the challenges to overcome at UHF is the coupling between the elements of the multichannel arrays which can cause SNR degradation. In this talk, new RF elements designed for operation at UHF which allow high performance human MR imaging of different ROIs, will be presented. Those elements are modified transmission line structures and are decoupled elements per se – there is no need for applying of additional decoupling methods. These elements are flexible and very robust towards bending and elongation comparing to the conventional elements. When elongated, these elements exhibit increased SNR in depth.
The biggest challenge at ultra-low field (mT) regime is low SNR which limits the application field and diagnostic value of low-field scanners and prevents their wide acceptance. In this talk, some new ideas and paradigms which overcome limitations of low field regime will be presented.

Talk Chaired by Dimitri Van De Ville, Ad Interim Head, CIBM MRI EPFL Animal Imaging & Technology Section, Head, CIBM SP EPFL-UNIGE Network Analysis & Functional MRI Section