Premium
Measurement of tissue blood flow using intravascular relaxation agents and resonance imaging
Author(s) -
Gore John C.,
Majumdar Sharmila
Publication year - 1990
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.1910140210
Subject(s) - blood flow , magnetic resonance imaging , nuclear magnetic resonance , relaxation (psychology) , biomedical engineering , medicine , radiology , physics
Simple concepts of indicator‐dilution techniques are described, and the theoretical basis of measuring regional blood flow via transit time measurements of a blood pool marker is discussed. Using very fast imaging of the effects of an appropriate and efficient relaxation agent, the concentration‐time curve of the agent can be quantified. Preliminary measurements of the transit of superparamagnetic iron oxide through a rat brain at 2.0 T have been obtained. There are problems, however, in relating the NMR signal change to the tissue concentration of an intra vascular relaxation agent when there is not fast exchange of the tissue water with the water in the vasculature, or when the precise efficacy of the agent varies with the geometrical arrangement of the capillaries. Studies of the effects of superparamagnetic iron oxide particles in different media confirm that the in vivo efficacy varies among different tissues, which complicates their use as blood flow markers. © 1990 Academic Press, Inc.