Nuclear magnetic resonance (NMR) techniques have been applied to the measurement of steady or quasi-steady flow by using, principally, the tag-detect method. This paper describes a two-magnet NMR flowmeter that can be used to measure pulsatile flow. The pulsatile nature of the flow causes a pulsed magnetization of the fluid, which is detected by a flow-sensitive NMR detector. A parabolic velocity profile has been assumed. The results of theoretical computations closely approximate in vitro data from a 1.6-mm ID rigid tube with respect to the shape of the NMR signal and to the proportionality of the NMR signal amplitude to flow rate. Selected in vivo results are also presented.
ASJC Scopus subject areas
- Biomedical Engineering