title: A correction algorithm for undersampled images using dynamic segmentation and entropy based focus criterion.
abstract: A post-processing technique is presented for correcting images undersampled in k-space. The method works by taking advantage of the image's background zeros (dynamically segmented through the application of a threshold) to extrapolate the missing k-space samples. The algorithm can produce good quality images from a small set of k-space frequencies with only a few iterations of simple matrix operations, using the image entropy as the focus criterion. It does not require any special patient preparation, extra pulse sequences, complex gradient programming or specialized hardware. This makes it a good candidate for any application that requires short scan times or where only few frequencies can be sampled.
authors.affiliation: Departamento de Ingeniería Eléctrica, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Lisboa
authors.forename: Marcelo
authors.initials: M
authors.lastname: Guarini
authors.forename: Pablo
authors.initials: P
authors.lastname: Irarrazaval
mesh_terms: D000465:Algorithms; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*