title: Accuracy of segmented MR velocity mapping to measure small vessel pulsatile flow in a phantom simulating cardiac motion.
abstract: The purpose of this study was to investigate the accuracy of conventional, segmented, and echo-shared MR velocity mapping sequences to measure pulsatile flow in small moving vessels using a phantom with simulated cardiac motion. The phantom moved either cyclically in-plane, through-plane, in- and through-plane, or was stationary. The mean error in average flow was -2% +/- 3% (mean +/- SD) for all sequences under all conditions, with or without background correction, as long as the region of interest (ROI) size was equal to the vessel cross-sectional size. Overestimation of flow as a result of an oversized ROI was less than 20%, and independent of field of view (FOV) and matrix, as long as the offset in angle between the imaging plane and flow direction was less than 10 degrees. Segmented velocity mapping sequences are surprisingly accurate in measuring average flow and render flow profiles in small moving vessels despite the blurring in the images due to vessel motion. J. Magn. Reson. Imaging 2001;13:722-728.
authors.affiliation: Department of Clinical Physiology, Lund University Hospital, Lund, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Arheden
authors.forename: M
authors.initials: M
authors.lastname: Saeed
authors.forename: E
authors.initials: E
authors.lastname: Törnqvist
authors.forename: G
authors.initials: G
authors.lastname: Lund
authors.forename: M F
authors.initials: MF
authors.lastname: Wendland
authors.forename: C B
authors.initials: CB
authors.lastname: Higgins
authors.forename: F
authors.initials: F
authors.lastname: Ståhlberg
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008432:Mathematical Computing; D008955:Models, Cardiovascular; D019047:Phantoms, Imaging; D011673:Pulsatile Flow / Q000502:physiology*; D012680:Sensitivity and Specificity