Design and evaluation of a 32-channel phased-array coil for lung imaging with hyperpolarized 3-helium.
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 alpha-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 (3)He lung imaging and demonstrate its ability to speed up imaging (3)He. 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 x 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.
Meise
Florian M
FM
Section of Medical Physics, Department of Diagnostic and Interventional Radiology, Johannes Gutenberg University Medical Center Mainz, Mainz, Germany.
Rivoire
Julien
J
Terekhov
Maxim
M
Wiggins
Graham C
GC
Keil
Boris
B
Karpuk
Sergej
S
Salhi
Zahir
Z
Wald
Lawrence L
LL
Schreiber
Laura M
LM
D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006371:Helium; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D007554:Isotopes; D008168:Lung / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers
D007554:Isotopes; D019275:Radiopharmaceuticals; D006371:Helium