ELECTRONIC POSTER - ismrm

14:00 5032. Prospective Motion Correction for Single-Voxel 1 H MR Spectroscopy
Brian Keating 1 , Weiran Deng 1 , J Cooper Roddey 2 , Nathan White 3 , Anders Dale 2 , V
Andrew Stenger 1 , Thomas Ernst 1
1 Department of Medicine, University of Hawaii, Honolulu, HI, United States; 2 Department of Neuroscience,
University of California at San Diego, La Jolla, CA, United States; 3 Department of Cognitive Science,
University of California at San Diego, La Jolla, CA, United States
Motion during brain 1 H MR spectroscopy acquisitions can compromise spectral quality. We adapted an image-based adaptive motion
correction module for use with a PRESS sequence. Sets of three orthogonal spiral navigator images are acquired in each TR period, to
estimate head motion in real-time. By applying the appropriate rotations and translations, the voxel can be made to remain stationary
with respect to the brain. Adaptive motion correction recovered original metabolite values (Cho/Cr ratio) to within a few percent even
for extensive head movements (20-30°), whereas non-navigated spectra showed marked changes in metabolite levels as well as
increased variability.
14:30 5033. PROspective MOtion Correction (PROMO) Results in Improved Image and
Segmentation Quality of High-Resolution MRI Scans of Children
Joshua M. Kuperman 1,2 , Timothy T. Brown, 23 , Matthew J. Erhart, 23 , J Cooper Roddey, 23 ,
Nathan Cooper White, 2,4 , Ajit Shankaranarayanan 5 , Eric T. Han 5 , Daniel Rettmann 6 ,
Anders M. Dale, 23
1 Radiology, UCSD, La Jolla, CA, United States; 2 Multimodal Imaging Lab, UCSD, La Jolla, CA, United States;
3 Neurosciences, UCSD, La Jolla, CA, United States; 4 Cognitive Science, UCSD, La Jolla, CA, United States;
5 Applied Science Lab, GE Healthcare, Menlo Park, CA, United States; 6 Applied Science Lab, GE Healthcare,
Rochester, MN, United States
In order to test the utility of PROspective MOtion correction (PROMO) for pediatric MRI research, nine children, ages 9-12, were
scanned four times with a high-resolution T1-weighted sequence. For each subject, PROMO on and off scans were collected in a
counterbalanced alternating pattern. Results show a qualitative enhancement in image clarity and reduction of apparent motion
artifacts with the use of PROMO. Furthermore, automated segmentations of PROMO-enabled images show significant improvements
in quality and reliability as compared to PROMO-off images. Volumetric segmentations of structures show consistently greater
percent volume overlap when PROMO is enabled.
15:00 5034. Pulsed Continuous Arterial Spin Labeling (PCASL) with Prospective Motion
Correction (PROMO)
Jian Zhang 1,2 , Greg Zaharchuk 2 , Michael Moseley 2 , Eric Han 3 , Nate White 4 , Cooper
Roddey 4 , Daniel Rettmann 5 , Anders Dale 4 , Joshua Kuperman 4 , Ajit Shankaranarayanan 3
1 Department of Electrical Engineering, Stanford University, Stanford, CA, United States; 2 Department of
Radiology, Stanford University, Stanford, CA, United States; 3 Global Applied Science Lab, GE Healthcare,
Menlo Park, CA, United States; 4 Department of Neuroscience, University of California, San Diego, La Jolla,
CA, United States; 5 Global Applied Science Lab, GE Healthcare, Rochester, MN, United States
Pulsed Continuous Arterial Spin Labeling (PCASL) is a promising whole-brain perfusion imaging technique, with good properties
such as high efficiency, 3D multi-slice capability, and low hardware demands. However, this sequence is vulnerable to patient motions
due to its long scan time. We demonstrate an improved perfusion imaging strategy by integrating the original PCASL sequence with a
PROspective MOtion (PROMO) correction module. The new sequence is much more robust against brain motion with little
interference between the imaging volume and PROMO navigators.
Thursday 13:30-15:30 Computer 121
13:30 5035. Catadioptric RGR Motion Tracking for Prospective Motion Compensation in MR
Acquisitions
Brian S. R. Armstrong 1 , Todd P. Kusik 1 , Robert T. Barrows 1 , Brian Andrews-Shigaki 2 ,
Julian Maclaren 3 , Maxim Zaitsev 3 , Oliver Speck 4 , Thomas Prieto 5 , Thomas Ernst 2
1 Electrical Engineering, Univ. Wisc.-Milwaukee, Milwaukee, WI, United States; 2 Medicine, University of
Hawaii, Honolulu, HI, United States; 3 Dept. of Diagnostic Radiology, University Hospital Freiburg, Freiburg,
Germany; 4 Biomedical Magnetic Resonance, Otto-von-Guericke University; 5 Neurology, Medical College of
Wisconsin, Wauwatosa, WI, United States
A retro-grate reflector (RGR) optical system for tracking motion in an MR bore is presented, including an RGR motion tracking
camera comprising a camera, lighting system and custom drive electronics in an RF enclosure, and a rib that has been engineered to
grip the inside surface of the MR bore and support a mirror, which permits viewing through a head coil opening with the RGR camera
positioned outside the head end of the MR bore. Evaluations of RF interference, mirror stability and tracking system noise are
presented.