International Journal on Magnetic Particle Imaging
Vol 3 No 1 (2017): Int J Mag Part Imag

Research Articles

Submillimeter-Accurate Marker Localization within Low Gradient Magnetic Particle Imaging Tomograms

Main Article Content

Florian Griese (Section for Biomedical Imaging, University Medical Center Hamburg, Hamburg, Germany), Tobias Knopp (Section for Biomedical Imaging, University Medical Center Hamburg, Hamburg, Germany), René Werner (Section for Image Processing and Medical Informatics, University Medical Center Hamburg, Hamburg, Germany), Alexander Schlaefer (Institute of Medical Technology, Hamburg University of Technology, Germany), Martin Möddel (Section for Biomedical Imaging, University Medical Center Hamburg, Hamburg, Germany)

Abstract

Magnetic Particle Imaging (MPI) achieves a high temporal resolution, which opens up a wide range of real-time medical applications such as device tracking and navigation. These applications usually rely on automated techniques for finding and localizing devices and fiducial markers in medical images. In this work, we show that submillimeter-accurate automatic marker localization from low gradient MPI tomograms with a spatial resolution of several millimeters is possible. Markers are initially identified within the tomograms by a thresholding-based segmentation algorithm. Subsequently, their positions are accurately determined by calculating the center of mass of the gray values inside the pre-segmented regions. A series of phantom measurements taken at full temporal resolution (46 Hz) is used to analyze statistical and systematical errors and to discuss the performance and stability of the automatic submillimeter-accurate marker localization algorithm.

Article Details