In vitro validation of phase-contrast flow measurements at 3 T in comparison to 1.5 T: precision, accuracy, and signal-to-noise ratios.
OBJECTIVE
To evaluate the signal-to-noise ratio (SNR), precision, and accuracy of phase-contrast flow measurements at 3 T with the help of an in vitro model and to compare the results with data from two 1.5-T scanners.


METHODS
Using an identical setup of a laminar flow model and sequence parameters, measurements were done at one 3-T and at two 1.5-T systems. Precision, accuracy, and SNR were obtained for velocity encodings ranging from 55 up to 550 cm(-1). SNRs were calculated from the magnitude as well as the flow encoded images.


RESULTS
Precision and accuracy for the in vitro flow model were similarly high in all scanners with no significant difference. For velocity encodings from 55 cm(-1) up to 550 cm(-1), the SNR in magnitude as well as phase encoded images of the 3-T measurements was approximately 2.5 times higher than the SNR obtained from the two 1.5-T systems.


CONCLUSIONS
Even without optimization for the 3-T environment, flow measurements show the same high accuracy and precision as is known from clinical 1.5-T scanners. The superior SNR at 3 T will allow further improvements in temporal and spatial resolution. This will be of interest for small-size vessels like coronary arteries or for slow diastolic flow patterns.
Lotz
Joachim
J
Department of Diagnostic Radiology, Hannover Medical School, 30625 Hannover, Germany. lotz.joachim@mh-hannover.de
Döker
Rolf
R
Noeske
Ralph
R
Schüttert
Meike
M
Felix
Roland
R
Galanski
Michael
M
Gutberlet
Matthias
M
Meyer
Gerd Peter
GP
D001783:Blood Flow Velocity / Q000502:physiology*; D066298:In Vitro Techniques; D018810:Magnetic Resonance Angiography / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results