Carlos
Sing-Long1,2, Vicente Parot1,2, Carlos Lizama3,
Sergio Uribe, 2,4, Cristian Tejos1,2, Pablo Irarrazaval1,2
1Department of Electrical Engineering,
Pontificia Universidad Catolica de Chile, Santiago, Chile; 2Biomedical
Imaging Center, Pontificia Universidad Catolica de Chile, Santiago, Chile; 3Department
of Mathematics and Computer Science, Universidad de Santiago de Chile,
Santiago, Chile; 4Department of Radiology, Pontificia Universidad
Catolica de Chile, Santiago, Chile
In
Magnetic Resonance Imaging (MRI) the distortions produced by field
inhomogeneities can be corrected with post processing techniques, e.g. linear
correction and conjugate phase reconstruction methods. However, these methods
do not provide a theoretical framework to analyze the distortions. In this
work, we propose the Fractional Fourier Transform (FrFT) as a way to study
the distortions produced by quadratic field inhomogeneities. We analyze some
commonly used sequences to exemplify the usefulness of this method. We also
show how this analysis can be used to reconstruct artifact-free images
obtained from non homogeneous fields.