Abstract
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 intravascular 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.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
