Akademska digitalna zbirka SLovenije - logo
E-resources
Peer reviewed Open access
  • Are Movement Artifacts in M...
    Havsteen, Inger; Ohlhues, Anders; Madsen, Kristoffer H; Nybing, Janus Damm; Christensen, Hanne; Christensen, Anders

    Frontiers in neurology, 05/2017, Volume: 8
    Journal Article

    Movement artifacts compromise image quality and may interfere with interpretation, especially in magnetic resonance imaging (MRI) applications with low signal-to-noise ratio such as functional MRI or diffusion tensor imaging, and when imaging small lesions. High image resolution has high sensitivity to motion artifacts and often prolongs scan time that again aggravates movement artifacts. During the scan fast imaging techniques and sequences, optimal receiver coils, careful patient positioning, and instruction may minimize movement artifacts. Physiological noise sources are motion from respiration, flow and pulse coupled to cardiac cycles, from the swallowing reflex and small spontaneous head movements. Par example, in resting-state functional MRI spontaneous neuronal activity adds 1-2% of signal change, even under optimal conditions signal contributions from physiological noise remain a considerable fraction hereof. Movement tracking during imaging may allow for prospective correction or postprocessing steps separating signal and noise.