Paper Info
Title
Susceptibility, echo time shifts, and T2* considerations for functional magnetic resonance imaging
Abstract
Magnetic susceptibility differences exist near the interface of air/tissue in the ventral brain in fMRI (functional magnetic resonance imaging). These susceptibility differences will not only cause field inhomogeneity and its gradients which will result in image artifacts, but also cause shifts in the echo time for gradients echo acquisitions. The echo time shifts are caused by shifts in the effective k-space trajectory due to the gradients of the field inhomogeneity. Previous work has shown and validated methods for estimating the echo time shift based on the effective k-space trajectory. In this work, we demonstrate that accurate estimation of the R2* decay map (R2*=1/T2*) not only need to account for the field map and its gradients, but also needs to include the echo time shift. These changes in T2* sensitivity are directly related to changes in sensitivity in BOLD (blood oxygenation level dependent) fMRI studies.
Year
DOI
Venue
2009
10.1109/ISBI.2009.5193146
ISBI
Keywords
Field
DocType
magnetic susceptibility difference,decay map,fmri study,effective k-space trajectory,field inhomogeneity,previous work,echo time,functional magnetic resonance imaging,echo time shift,field map,magnetic fields,image reconstruction,data acquisition,trajectory,magnetic resonance imaging,magnetic susceptibility
Magnetic susceptibility,Iterative reconstruction,Magnetic field,Functional magnetic resonance imaging,Computer science,Blood oxygenation level dependent,Nuclear magnetic resonance,Trajectory,Magnetic resonance imaging
Conference
Citations 
PageRank 
References 
0
0.34
5
Authors
2
Name
Order
Citations
PageRank
Brad Sutton119927.18
Yue Zhuo2182.90