A Novel Algorithm for Fast 3D Localisation of N Fiducial Markers from 1D Projections

Djordje Brujic¹, Francesca Galassi¹, Marc Rea¹, Michael Ristic²

We propose an algorithm for localising N fiducial markers within the imaging volume of the MR scanner to accurately track devices in real-time. Our algorithm computes the 3D position of fiducial markers from a set of 1D projections in space using a novel approach which improves previous methods. The algorithm was verified through extensive simulations, implemented and tested using wireless fiducial markers and a modified FLASH sequence. We achieved a computational time of 5 ms with 3 fiducial markers, a refresh rate of 10 times/s and a maximum error of 2.4 mm. Our algorithm is in line with the requirements of interventional procedures.