Free breathing myocardial perfusion MRI with SW-CG-HYPR using motion correction
- PDF / 1,415,521 Bytes
- 3 Pages / 610 x 792 pts Page_size
- 41 Downloads / 197 Views
BioMed Central
Open Access
Poster presentation
Free breathing myocardial perfusion MRI with SW-CGHYPR using motion correction Lan Ge*1, Aya Kino1, Mark Griswold2, James Carr1 and Debiao Li1 Address: 1Northwestern University, Chicago, IL, USA and 2Case Western Reserve University, Cleveland, OH, USA * Corresponding author
from 13th Annual SCMR Scientific Sessions Phoenix, AZ, USA. 21-24 January 2010 Published: 21 January 2010 Journal of Cardiovascular Magnetic Resonance 2010, 12(Suppl 1):P205
doi:10.1186/1532-429X-12-S1-P205
Abstracts of the 13th Annual SCMR Scientific Sessions - 2010
Meeting abstracts - A single PDF containing all abstracts in this Supplement is available here. http://www.biomedcentral.com/content/files/pdf/1532-429X-11-S1-infoThis abstract is available from: http://jcmr-online.com/content/12/S1/P205 © 2010 Ge et al; licensee BioMed Central Ltd.
Introduction The diagnostic value of first-pass perfusion MRI is limited by the low spatial coverage, resolution, SNR, and motion artifacts. Sliding-Window Conjugate-Gradient HYPR [1] (SW-CG-HYPR) has been proposed to acquire perfusion images with increased spatial coverage, better spatial resolution, and improved SNR [2]. However, this method is sensitive to the respiratory motion and thus limited to the breath hold. Motion correction may be useful to reduce motion artifacts and allow for free-breathing first-pass perfusion.
Purpose To develop and test a non-model-based motion correction method combined with SW-CG-HYPR to perform free-breathing myocardial MR imaging.
Methods An ECG-triggered, multi-slice FLASH sequence with radial sampling was used. As shown in Figure 1, radial sampling was applied in a segmented interleaved fashion. Multiple slices were acquired after each saturation recovery prepulse. The motion correction method is illustrated in Figure 2. Both translation and rotation of the heart were detected in image domain by calculating the normalized cross-correlation coefficients. Motion correction was performed in k-space by rotating the undersampled k-space and shifting the phase by a factor of exp(-2πi(δx/Nread+δy/ Npe)), where δx and δy are the number of pixels to shift in × and y direction, and Nread and Npe are the total number of pixels along readout and phase encoding direction. Sliding window was used to reconstruct the composite
images, and the time-resolved images were reconstructed after CG-HYPR processing. Six healthy volunteers were scanned using a 1.5 T system, with and without breath hold, during first-pass of the contrast agent. Imaging parameters included: TR/TE/flip-angle = 3.2/1.6 ms/10º, spatial resolution = 1.3 × 1.3 × 10 mm3, and number of slices = 6. The images were qualitatively graded by a reviewer using a score of 1-4 (1: worse; 4: best), and the signal changes vs. time curves were compared.
Results The average image quality score of the free-breathing images with motion correction (3.09 ± 0.37) is significantly higher than those without motion correction (2.26 ± 0.40), and is comparable to the suc
Data Loading...
