Actuation and Tracking of Ferromagnetic Objects Using MRI

The MRI is a common medical imaging modality with powerful properties for diagnostic imaging. In order to enable robotic approaches for medical therapies like targeted drug delivery and others, the MRI systems suitability for actuation has been evaluated and exploited recently. The technologies used for imaging like coils, etc., can also be used to exert forces on ferromagnetic objects. In this article, a tracking algorithm for the three-dimensional tracking of ferromagnetic objects inside the MRI is presented. It only relies on the acquisition of single slices, which intersect the generated artifact volume. Additionally, some factors influencing the imaging and tracking are discussed, as well as the generated force measured and compared to theoretical values.