Premium
Improvements in MR Angiography Using Phase‐Corrected Data Sets
Author(s) -
Chenevert Thomas L.,
Fechner Klaus P.,
Gelblum Daphna Y.
Publication year - 1989
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.1910100104
Subject(s) - dephasing , projection (relational algebra) , subtraction , phase (matter) , digital subtraction angiography , image subtraction , signal (programming language) , computer science , artificial intelligence , algorithm , mathematics , computer vision , angiography , physics , image (mathematics) , image processing , radiology , medicine , binary image , arithmetic , quantum mechanics , programming language
The objective of this work is refinement of an MR angiography technique via postprocessing removal of phase errors which inhibit static signal subtraction. Projective views of the object are obtained using interleaved flow‐compensated and noncompensated gradient waveforms. Complex subtraction of data sets is required since a projection dephase pulse is used for static signal suppression. This renders the difference image susceptible to systematic phase errors which are modeled asa smoothly varying multiplicative phase function. The error function is estimated by comparison of heavily spatial filtered renditions of the object acquired without projection dephasing in order to minimize influence of flow. The phase correction is then applied to high‐resolution data sets collected with projection dephasing to enhance flow sensitivity. The technique is demonstrated by improvement of MR angiograms of rats acquired on a 2‐T, 31‐cm‐bore system. © 1989 Academic Press. Inc.