Abstract:
:The purpose of this work was to implement autocalibrating GRAPPA-based parallel imaging (PI) for in vivo high-resolution (HR) MRI of cartilage and trabecular bone micro-architecture at 7T and to evaluate its performance based on comparison of MR-derived morphology metrics between accelerated and conventional images and comparison of geometry factor measures between 3T and 7T. Using an eight channel coil array for trabecular MRI at the ankle, a higher maximum feasible acceleration (R) = 6 and lower geometry factor values than that at 3T were observed. The advantages of two-dimensional acceleration were also demonstrated. In knee cartilage and bone acquisitions, feasibility of PI with a dual-channel quadrature coil was investigated. Robust quantification of bone and cartilage metrics could be derived from accelerated ankle and knee acquisitions. PI can enhance the clinical feasibility of in vivo bone and cartilage HR-MRI for osteoporosis and osteoarthritis at 7T.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Banerjee S,Krug R,Carballido-Gamio J,Kelley DA,Xu D,Vigneron DB,Majumdar Sdoi
10.1002/mrm.21455subject
Has Abstractpub_date
2008-03-01 00:00:00pages
655-60issue
3eissn
0740-3194issn
1522-2594journal_volume
59pub_type
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