Design and evaluation of a 32‐channel phased‐array coil for lung imaging with hyperpolarized 3‐helium

Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts, USA
Magnetic Resonance in Medicine (Impact Factor: 3.4). 02/2010; 63(2):456 - 464. DOI: 10.1002/mrm.22265

ABSTRACT Imaging with hyperpolarized 3-helium is becoming an increasingly important technique for MRI diagnostics of the lung but is hampered by long breath holds (>20 sec), which are not always applicable in patients with severe lung disease like chronic obstructive pulmonary disease (COPD) or α-1-anti-trypsin deficiency. Additionally, oxygen-induced depolarization decay during the long breath holds complicates interpretation of functional data such as apparent diffusion coefficients. To address these issues, we describe and validate a 1.5-T, 32-channel array coil for accelerated 3He lung imaging and demonstrate its ability to speed up imaging 3He. A signal-to-noise ratio increase of up to a factor of 17 was observed compared to a conventional double-resonant birdcage for unaccelerated imaging, potentially allowing increased image resolution or decreased gas production requirements. Accelerated imaging of the whole lung with one-dimensional and two-dimensional acceleration factors of 4 and 4 × 2, respectively, was achieved while still retaining excellent image quality. Finally, the potential of highly parallel detection in lung imaging is demonstrated with high-resolution morphologic and functional images. Magn Reson Med, 2010. © 2010 Wiley-Liss, Inc.

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