Impact of prospective motion correction, distortion correction methods and large vein bias on the spatial accuracy of cortical laminar fMRI at 9.4 Tesla
Jonas Bause,
Jonathan R. Polimeni,
Johannes Stelzer,
Myung-Ho In,
Philipp Ehses,
Pablo Kraemer-Fernandez,
Ali Aghaeifar,
Eric Lacosse,
Rolf Pohmann,
Klaus Scheffler
Affiliations
Jonas Bause
Department for Biomedical Magnetic Resonance Imaging, University Hospital Tuebingen, Germany; High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany; Graduate School of Neuronal and Behavioral Sciences, University of Tuebingen, Tuebingen, Germany; Corresponding author. Max-Planck-Ring 11, 72076, Tuebingen, Germany.
Jonathan R. Polimeni
Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Harvard Medical School, Massachusetts General Hospital, Charleston, MA, USA; Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA
Johannes Stelzer
Department for Biomedical Magnetic Resonance Imaging, University Hospital Tuebingen, Germany; High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
Myung-Ho In
Department of Radiology, Mayo Clinic, Rochester, MN, USA
Philipp Ehses
German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
Pablo Kraemer-Fernandez
Department of Prosthodontics, University Hospital Tuebingen, Tuebingen, Germany
Ali Aghaeifar
High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany; Graduate School of Neuronal and Behavioral Sciences, University of Tuebingen, Tuebingen, Germany
Eric Lacosse
High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany; Autonomous Learning Group, Max-Planck Institute for Intelligent Systems, Tuebingen, Germany
Rolf Pohmann
High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
Klaus Scheffler
Department for Biomedical Magnetic Resonance Imaging, University Hospital Tuebingen, Germany; High-Field Magnetic Resonance Center, Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
Functional imaging with sub-millimeter spatial resolution is a basic requirement for assessing functional MRI (fMRI) responses across different cortical depths and is used extensively in the emerging field of laminar fMRI. Such studies seek to investigate the detailed functional organization of the brain and may develop to a new powerful tool for human neuroscience. However, several studies have shown that measurement of laminar fMRI responses can be biased by the image acquisition and data processing strategies. In this work, measurements with three different gradient-echo EPI BOLD fMRI protocols with a voxel size down to 650 μm isotropic were performed at 9.4 T. We estimated how prospective motion correction can help to improve spatial accuracy by reducing the number of spatial resampling steps in postprocessing. In addition, we demonstrate key requirements for accurate geometric distortion correction to ensure that distortion correction maps are properly aligned to the functional data and that strong variations of distortions near large veins can lead to signal overlays which cannot be corrected for during postprocessing. Furthermore, this study illustrates the spatial extent of bias induced by pial and other larger veins in laminar BOLD experiments. Since these issues under investigation affect studies performed with more conventional spatial resolutions, the methods applied in this work may also help to improve the understanding of the BOLD signal more broadly.
