Reconstruction of undersampled dynamic images by modeling the motion of object elements

Prieto, C; Batchelor, PG; Hill, DLG; Hajnal, JV; Guarini, M.; Irarrázaval P.

Abstract

Dynamic MRI is restricted due to the time required to obtain enough data to reconstruct the image sequence. Several undersampled reconstruction techniques have been proposed to reduce the acquisition time. In most of these techniques the nonacquired data are recovered by modeling the temporal information as varying pixel intensities represented in time or in temporal frequencies. Here we propose a new approach that recovers the missing data through a motion estimation of the object elements ("obels," or pieces of tissue) of the image. This method assumes that an obel displacement through the sequence has lower bandwidth than fluctuations in pixel intensities caused by the motion, and thus it can be modeled with fewer parameters. Preliminary results show that this technique can effectively reconstruct (with root mean square (RMS) errors below 4%) cardiac images and joints with undersampling factors of 8 and 4, respectively. Moreover, in the reconstruction process an approximation of the motion vectors is obtained for each obel, which can be used to quantify dynamic information. In this method the motion need not be confined to a part of the field of view (FOV) or to a portion of the temporal frequency. It is appropriate for dynamic studies in which the obels' motion model has fewer parameters than the number of acquired samples. © 2007 Wiley-Liss, Inc.

Más información

Título según WOS: Reconstruction of undersampled dynamic images by modeling the motion of object elements
Título según SCOPUS: Reconstruction of undersampled dynamic images by modeling the motion of object elements
Título de la Revista: MAGNETIC RESONANCE IN MEDICINE
Volumen: 57
Número: 5
Editorial: LIPPINCOTT WILLIAMS & WILKINS
Fecha de publicación: 2007
Página de inicio: 939
Página final: 949
Idioma: English
URL: http://doi.wiley.com/10.1002/mrm.21222
DOI:

10.1002/mrm.21222

Notas: ISI, SCOPUS