๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Dynamic image reconstruction: MR movies from motion ghosts

โœ Scribed by Qing-San Xiang; R. Mark Henkelman


Book ID
102905195
Publisher
John Wiley and Sons
Year
1992
Tongue
English
Weight
759 KB
Volume
2
Category
Article
ISSN
1053-1807

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โœฆ Synopsis


Abstract

It has been previously shown that an image with motion ghost artifacts can be decomposed into a ghost mask superimposed over a ghostโ€free image. The present study demonstrates that the ghost components carry useful dynamic information and should not be discarded. Specifically, ghosts of different orders indicate the intensity and phase of the corresponding harmonics contained in the quasiโ€periodically varying spinโ€density distribution. A summation of the ghosts weighted by appropriate temporal phase factors can give a timeโ€dependent dynamic image that is a movie of the object motion. This dynamic image reconstruction technique does not necessarily require monitoring of the motion and thus is easy to implement and operate. It also has a shorter imaging time than pointโ€byโ€point imaging of temporal variation, because the periodic motion is more efficiently sampled with a limited number of harmonics recorded in the motion ghosts. This technique was tested in both moving phantoms and volunteers. It is believed to be useful for dynamic imaging of timeโ€varying anatomic structures, such as in the cardiovascular system.


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