Theory and application of static field inhomogeneity effects in gradient-echo imaging

• Published in: Journal of magnetic resonance imaging Vol. 7; no. 2; p. 266
• Main Authors: Reichenbach, J R, Venkatesan, R, Yablonskiy, D A, Thompson, M R, Lai, S, Haacke, E M
• Format: Journal Article
• Language: English
• Published: United States 01.03.1997
• Subjects: Brain - anatomy & histology; Brain Diseases - diagnosis; Brain Mapping - methods; Echo-Planar Imaging - instrumentation; Echo-Planar Imaging - methods; Humans; Models, Theoretical; Radiographic Image Enhancement; Reference Values; Sensitivity and Specificity
• ISSN: 1053-1807
• DOI: 10.1002/jmri.1880070203

The influence of local static magnetic field inhomogeneities on gradient-echo imaging is discussed and the underlying theoretical aspects are reviewed. A high-resolution approach is suggested to suppress image distortion and restore signal loss due to spin dephasing. Acquisition of three-dimensional data sets not only overcomes part of the limitations associated with gradient echoes but also makes it possible to extract local information about the strength or direction of background gradients and relative susceptibility changes between different tissues. Applications of the suggested approach in the human brain for anatomical imaging as well as for extraction of physical and physiological parameters are presented and discussed.