Malte Riedel (né Steinhoff)1, Kawin Setsompop2,3,4, Alfred Mertins1, and Peter Börnert5,6
1Institute for Signal Processing, University of Lübeck, Lübeck, Germany, 2Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 3Department of Radiology, Harvard Medical School, Boston, MA, United States, 4Harvard‐MIT Health Sciences and Technology, MIT, Cambridge, MA, United States, 5Philips Research, Hamburg, Germany, 6Department of Radiology, C.J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, Netherlands
1Institute for Signal Processing, University of Lübeck, Lübeck, Germany, 2Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, United States, 3Department of Radiology, Harvard Medical School, Boston, MA, United States, 4Harvard‐MIT Health Sciences and Technology, MIT, Cambridge, MA, United States, 5Philips Research, Hamburg, Germany, 6Department of Radiology, C.J. Gorter Center for High-Field MRI, Leiden University Medical Center, Leiden, Netherlands
The
proposed method offers navigated retrospective 3D rigid motion correction per
EPI-shot for interleaved SMS brain DWI. Simulations
confirm small submillimeter target registration errors.
In-vivo
DTI results show improved image quality at a high temporal resolution of 3 Hz.
Figure 4: In-vivo examples from 4-interleave 3-SMS
full-volume DWI reconstructions. a: SMS-IRIS
and MoSaIC examples. b: Shot-wise shift and rotation parameters for MoSaIC (see
color code). In the static case (blue), the parameters are almost constant and
the images appear similar. The SMS-IRIS images of the next two examples (orange
and green) are visibly blurred by in-plane motion, which is improved by MoSaIC.
The last two SMS-IRIS images (red and purple) are mainly affected by
through-plane motion, which is detected as x-rotations and y-shifts and
improved by MoSaIC.
Figure 1: MoSaIC
scheme for navigated DWI reconstruction per diffusion direction including 3D
rigid motion correction. SMS
navigators are unfolded using 2D-SENSE. The shots from the first
diffusion-weighted TR are assumed motion-free and stacked to the reference
volume. The navigator SMS groups are registered by SMS2Vol registration, the
shot diffusion phases
are extracted and rejection criteria
are
calculated. All shot parameters are included into a motion-corrected
full-volume reconstruction combining the high-resolution image data.