文档介绍：Page 1 of 33
Distributed Large-Scale Simulation of MR Imaging
Andreas R. Brenner, Jürgen Kürsch and Tobias G. Noll*
Chair of Electrical Engineering puter Systems
Aachen University of Technology
Germany
*Address for correspondence:
Chair of Electrical Engineering puter Systems, RWTH Aachen,
Schinkelstr. 2, 52056 Aachen, Germany
e-mail: ******@-
Tel.: ++49 241 80 97601
Fax: ++49 241 80 92282
Keywords:
MRI, simulation, bloch equation, puting, education
Total number of pages: 33
Total number of figures: 11
Total number of tables: 1
Published in MAGMA 5(2), 1997
Page 2 of 33
Abstract
The concept and the implementation of a parallelized and spin based simulator for MR imag-
ing is presented. The dynamics of ization are modelled using the Bloch equation cover-
ing arbitrary RF pulses, gradients, main field inhomogeneity and relaxation. A temporal
position of a given sequence is introduced leading to basic sequence elements called
atoms. A concept of spatial sampling of the object by spins is proposed, in the course of which
Shannon‘s sampling theorem must be respected. In biomedical MR imaging, spins can be
modelled as non-interacting entities, permitting an efficient parallelization of the simulation.
The simulator ParSpin was implemented on a heterogeneous, interconnected cluster of work-
stations based on existing message passing libraries. munication overhead has been
kept moderately small. The puting performance of many processors enables the
research into plex problems, . three-dimensional or steady-state MR experiments
requiring up to106 spins. Additionally, ParSpin allows prehensive visualization for edu-
cational purposes.
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Introduction
The simulation of MR imaging is an plement to performing real MR experi-
ments. Not only is simulation a tool for acquiring general theoretical understanding, but the
independent analysis of the parameters of the plex MR technology also permits the
i