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Prospective motion correction of 3D echo-planar imaging data for functional MRI using optical tracking.

Todd N, Josephs O, Callaghan MF, Lutti A, Weiskopf N - Neuroimage (2015)

Bottom Line: Metrics were developed to quantify the amount of motion as it occurred relative to k-space data acquisition.The PMC system did not introduce extraneous artifacts for the no motion conditions and improved the time series temporal signal-to-noise by 30% to 40% for all combinations of low/high resolution and slow/fast head movement relative to the standard acquisition with no prospective correction.The numbers of activated voxels (p<0.001, uncorrected) in both task-based experiments were comparable for the no motion cases and increased by 78% and 330%, respectively, for PMC on versus PMC off in the slow motion cases.

View Article: PubMed Central - PubMed

Affiliation: Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London, UK. Electronic address: nicholas.todd@ucl.ac.uk.

No MeSH data available.


Example plots of motion data from Volunteer #2. The plots in panels A and B show the three translation and three rotation measurements from the optical camera (fast motion case). Panels C–E show the motion metrics calculated from the camera data for cases of no motion (C), slow motion (D), and fast motion (E, with data corresponding to plots in panels A and B). The grid lines indicate the timing of the MR volume acquisition. Note the different scale on the axes for panels C–E.
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f0010: Example plots of motion data from Volunteer #2. The plots in panels A and B show the three translation and three rotation measurements from the optical camera (fast motion case). Panels C–E show the motion metrics calculated from the camera data for cases of no motion (C), slow motion (D), and fast motion (E, with data corresponding to plots in panels A and B). The grid lines indicate the timing of the MR volume acquisition. Note the different scale on the axes for panels C–E.

Mentions: Fig. 2 shows an example of the motion data that the camera captures and how it is used to create the motion metrics. The three translation and three rotation measurements shown in Figs. 2A and B were from Volunteer #2 during experimental conditions of 1.5 mm resolution imaging, PMC off, and fast head motion. The amplitude of the movements shown in these plots was similar across volunteers. It is larger and more frequent than the type of motion typically seen in fMRI studies with healthy volunteers but roughly in line with the amplitude of motion seen in certain patient populations (Kochunov et al., 2006; Lemieux et al., 2007; Schulz et al., 2014; Versluis et al., 2010). Figs. 2C–E show the motion metrics of total speed, integrated motion, and partition-weighted integrated motion, all from Volunteer #2 with PMC off and no, slow, and fast motion respectively. The data shown in Fig. 2E corresponds to the data shown in Figs. 2A and B, giving an indication of how the metrics M and MPW are related to the translation and rotation measurements. The grid lines indicate the timing of the MR data acquisition per image volume and the dot markers on the motion metrics indicate the timing of the central k-space partition.


Prospective motion correction of 3D echo-planar imaging data for functional MRI using optical tracking.

Todd N, Josephs O, Callaghan MF, Lutti A, Weiskopf N - Neuroimage (2015)

Example plots of motion data from Volunteer #2. The plots in panels A and B show the three translation and three rotation measurements from the optical camera (fast motion case). Panels C–E show the motion metrics calculated from the camera data for cases of no motion (C), slow motion (D), and fast motion (E, with data corresponding to plots in panels A and B). The grid lines indicate the timing of the MR volume acquisition. Note the different scale on the axes for panels C–E.
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4441089&req=5

f0010: Example plots of motion data from Volunteer #2. The plots in panels A and B show the three translation and three rotation measurements from the optical camera (fast motion case). Panels C–E show the motion metrics calculated from the camera data for cases of no motion (C), slow motion (D), and fast motion (E, with data corresponding to plots in panels A and B). The grid lines indicate the timing of the MR volume acquisition. Note the different scale on the axes for panels C–E.
Mentions: Fig. 2 shows an example of the motion data that the camera captures and how it is used to create the motion metrics. The three translation and three rotation measurements shown in Figs. 2A and B were from Volunteer #2 during experimental conditions of 1.5 mm resolution imaging, PMC off, and fast head motion. The amplitude of the movements shown in these plots was similar across volunteers. It is larger and more frequent than the type of motion typically seen in fMRI studies with healthy volunteers but roughly in line with the amplitude of motion seen in certain patient populations (Kochunov et al., 2006; Lemieux et al., 2007; Schulz et al., 2014; Versluis et al., 2010). Figs. 2C–E show the motion metrics of total speed, integrated motion, and partition-weighted integrated motion, all from Volunteer #2 with PMC off and no, slow, and fast motion respectively. The data shown in Fig. 2E corresponds to the data shown in Figs. 2A and B, giving an indication of how the metrics M and MPW are related to the translation and rotation measurements. The grid lines indicate the timing of the MR data acquisition per image volume and the dot markers on the motion metrics indicate the timing of the central k-space partition.

Bottom Line: Metrics were developed to quantify the amount of motion as it occurred relative to k-space data acquisition.The PMC system did not introduce extraneous artifacts for the no motion conditions and improved the time series temporal signal-to-noise by 30% to 40% for all combinations of low/high resolution and slow/fast head movement relative to the standard acquisition with no prospective correction.The numbers of activated voxels (p<0.001, uncorrected) in both task-based experiments were comparable for the no motion cases and increased by 78% and 330%, respectively, for PMC on versus PMC off in the slow motion cases.

View Article: PubMed Central - PubMed

Affiliation: Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, University College London, London, UK. Electronic address: nicholas.todd@ucl.ac.uk.

No MeSH data available.