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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.


Related in: MedlinePlus

Mini bite bar set up used to securely attach the tracking marker to the subject. A) Each bite bar was individually molded to the volunteer's upper front teeth using a medical grade hydroplastic (TAK Systems) and included a two-hinge mounting system for flexible placement of the tracking marker. B) Image of a volunteer with the mini bite bar and tracking marker taken from approximately the same angle as where the camera would be located in the scanner bore.
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f0005: Mini bite bar set up used to securely attach the tracking marker to the subject. A) Each bite bar was individually molded to the volunteer's upper front teeth using a medical grade hydroplastic (TAK Systems) and included a two-hinge mounting system for flexible placement of the tracking marker. B) Image of a volunteer with the mini bite bar and tracking marker taken from approximately the same angle as where the camera would be located in the scanner bore.

Mentions: All scanning was performed on a Siemens TIM Trio scanner using a standard 32-channel head coil and with volunteer informed consent obtained under the approval of the institution's local ethics committee. Five healthy volunteers were scanned under task-free fMRI conditions and one of the volunteers was also scanned in two separate task fMRI sessions. Custom made mini bite bars were used to rigidly attach the Moire phase marker to the front upper teeth of the volunteer, thereby ensuring the best coupling of marker and head movement (see Fig. 1).


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)

Mini bite bar set up used to securely attach the tracking marker to the subject. A) Each bite bar was individually molded to the volunteer's upper front teeth using a medical grade hydroplastic (TAK Systems) and included a two-hinge mounting system for flexible placement of the tracking marker. B) Image of a volunteer with the mini bite bar and tracking marker taken from approximately the same angle as where the camera would be located in the scanner bore.
© Copyright Policy - CC BY
Related In: Results  -  Collection

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

f0005: Mini bite bar set up used to securely attach the tracking marker to the subject. A) Each bite bar was individually molded to the volunteer's upper front teeth using a medical grade hydroplastic (TAK Systems) and included a two-hinge mounting system for flexible placement of the tracking marker. B) Image of a volunteer with the mini bite bar and tracking marker taken from approximately the same angle as where the camera would be located in the scanner bore.
Mentions: All scanning was performed on a Siemens TIM Trio scanner using a standard 32-channel head coil and with volunteer informed consent obtained under the approval of the institution's local ethics committee. Five healthy volunteers were scanned under task-free fMRI conditions and one of the volunteers was also scanned in two separate task fMRI sessions. Custom made mini bite bars were used to rigidly attach the Moire phase marker to the front upper teeth of the volunteer, thereby ensuring the best coupling of marker and head movement (see Fig. 1).

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.


Related in: MedlinePlus