German MR, radar prototype corrects for heart movement during imaging
A prototype has been developed at the Physikalisch Technische Bundesanstalt in Braunschweig, Germany, to correct for heart movements during MRI with the aid of an ultra-broadband radar device.

The interdisciplinary research project ultraMEDIS is aimed at using ultra-wideband (UWB) radar techniques for the detection of tumours, as well as for navigation technology in MRI.

UWB electromagnetic pulses (spectral bandwidth up to 10 GHz) generated by an UWB radar and transmitted by an antenna are able to probe the human body with low integral power (~ 1 mW), because electromagnetic waves can propagate through the body and are reflected at interfaces between materials with different dielectric properties. The receiving antenna detects the reflected signals coming from different depths of the body, according to PTB researchers.

At the institute, a demonstrator for the evaluation of the principal feasibility of an MR-UWB combination has been realized, the researchers said. With an MR-compatible UWB radar, the characteristic landmarks of the heart muscle during breathing could be followed without disturbing the actual MR measurement. Thus, both a real-time adjustment of the MR frequency according to the current position of the heart or a retrospective position correction of the MR data could be carried out.

The project is being carried out in cooperation with the Technical University of Ilmenau in Ilmenau, Germany, and with medical partners from University of Jena in Thuringia, Germany. The project is funded by the German Research Foundation, which will support research for six years.