A 24-ch Phased-Array System for Hyperpolarized Helium Gas Parallel MRI to Evaluate Lung Functions.
Hyperpolarized 3He gas MRI has a serious potential for assessing pulmonary functions. Due to the fact that the non-equilibrium of the gas results in a steady depletion of the signal level over the course of the excitations, the signal-tonoise ratio (SNR) can be independent of the number of the data acquisitions under certain circumstances. This provides a unique opportunity for parallel MRI for gaining both temporal and spatial resolution without reducing SNR. We have built a 24-channel receive / 2-channel transmit phased array system for 3He parallel imaging. Our in vivo experimental results proved that the significant temporal and spatial resolution can be gained at no cost to the SNR. With 3D data acquisition, eight fold (2x4) scan time reduction can be achieved without any aliasing in images. Additionally, a rigid analysis using the low impedance preamplifier for decoupling presented evidence of strong coupling.
Lee
Ray
R
New York University Medical Center, 660 First Ave. First Floor, New York, NY 10016.
Johnson
Glyn
G
Stefanescu
Cornel
C
Trampel
Robert
R
McGuinness
Georgeann
G
Stoeckel
Bernd
B