Assessment and compensation of susceptibility artifacts in gradient echo MRI of hyperpolarized 3He gas.
The effects of macroscopic background field gradients upon 2D gradient echo images of inhaled (3)He in the human lung were investigated at 1.5 T. Effective compensation of in-slice signal loss in (3)He gradient echo images was then demonstrated using a multiple acquisition interleaved single gradient echo sequence. This method restores signal dephasing through a combination of separate images acquired with different slice refocusing gradients. In vivo imaging of volunteers with the sequence shows substantial restoration of signal at the lung periphery and close to blood vessels. The technique presented may be useful when using (3)He MRI for volumetric measurements of lung ventilation and in studies using (3)He combined with intravenous contrast as a means of assessing lung ventilation/perfusion (V/Q).
Wild
Jim M
JM
Unit of Academic Radiology, University of Sheffield, Sheffield, UK. j.m.wild@sheffield.ac.uk
Fichele
Stan
S
Woodhouse
Neil
N
Paley
Martyn N J
MN
Swift
Andrew
A
Kasuboski
Larry
L
van Beek
Edwin J R
EJ
D016477:Artifacts; D003287:Contrast Media; D006371:Helium / Q000008:administration & dosage; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007554:Isotopes; D008168:Lung / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging; D012123:Pulmonary Ventilation
D003287:Contrast Media; D007554:Isotopes; D006371:Helium