Comparison of inversion recovery asymmetrical spin-echo EPI and gradient-echo EPI for brain motor activation study.
An inversion recovery asymmetric spin-echo (IR-ASE) echo-planar imaging (EPI) sequence has been developed for functional studies of the brain. This technique uses an 180 degrees inversion pulse with a long inversion time (TI) to suppress the pulsatile cerebrospinal fluid and an asymmetric spin-echo readout to obtain activation signals from brain capillaries. Because gradient-echo sequences are most sensitive to large vessels, motor cortex activation studies using a gradient-echo technique also were conducted for comparison with the IR-ASE method. The results suggest that the IR-ASE pulse sequence may be a useful complement to the gradient-echo technique for the study of neuronal activity of the human brain.
Zheng
J
J
Department of Radiology, College of Medicine, University of Iowa, Iowa City 52242, USA.
Ehrhardt
J C
JC
Cizadlo
T
T
Yuh
W T
WT
D001931:Brain Mapping; D017352:Echo-Planar Imaging / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods; D009043:Motor Activity / Q000502:physiology; D009044:Motor Cortex / Q000502:physiology*; D019047:Phantoms, Imaging; D012016:Reference Values; D012680:Sensitivity and Specificity