AUTHORS: Alexey Protopopov
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ABSTRACT: Gradient recalled echo (GRE) sequences are nowadays routinely used in clinical applications of magnetic resonance imaging (MRI). Contrast of GRE images is determined by several different physical mechanisms, like proton density, T2 relaxation time, gradients of magnetic field, and spatial heterogeneities of spin-spin interaction. Although the combined effect of all these parameters is of great value for physicians, it is possible that their separate mapping may reveal new features, that are masked in traditional GRE images. Separate mapping of physical parameters, contributing to contrast of GRE images, is called the parameterization, and has not been entirely solved by now. The present publication reports on development of the necessary tools for the solution. Finally, results obtained on volunteers are presented
KEYWORDS: Gradient recalled echo (GRE); relaxation function; least squares; magnetic gradients
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