Comparison of magnitude and complex data fitting for quantitative water/fat imaging
نویسندگان
چکیده
INTRODUCTION Magnitude fitting has been proposed as an alternative to complex data fitting for quantitative chemical shift-encoded water/fat imaging. Advantages of magnitude fitting include the removal of sensitivity to phase errors in the signal (e.g., caused by eddy currents) [1] and suppression of B0 field inhomogeneity effects (i.e., removal of one nonlinear parameter from the signal model) [2]. However, the noise performance of magnitude fitting, relative to complex fitting, has not been established. In this work, we perform a quantitative comparison of both methods, based on the bias and standard deviation of their estimates. The comparison uses theoretical Cramer-Rao Lower Bound (CRLB) results, simulation results and phantom data.
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