PURPOSE: We examined the spatial factors influencing magnetic resonance (MR) flow velocity measurements in a small tube phantom and used the same measurements obtained with an intraluminal Doppler guidewire as reference. MATERIALS AND METHODS: We generated constant flow velocities from approximately 40 to 370 cm/s in a tube 4 mm in diameter. We then performed segmented k-space, phase-contrast cine-MR imaging to quantify spatial peak flow velocities of one pixel and of five adjacent pixels as well as spatial mean velocities within regions of interest in a cross section of the phantom. Pixel dimensions ranged from 1.00 x 1.00 mm to 2.50 x 2.50 mm. We compared the MR measurements with the temporally averaged Doppler spectral peak velocities. RESULTS: For one pixel (r > 0.99: MR flow velocity for pixel dimension 1.00 x 1.00 mm = 1.03x + 9.8 cm/s), the linear correlation was excellent between flow velocities by MR and Doppler guidewire methods. However, for the five adjacent pixels, MR measurements were significantly underestimated using pixels 1.25 x 1.25 mm to 2.50 x 2.50 mm and for mean velocities for all pixel dimensions. CONCLUSION: Relatively high spatial resolution allows accurate MR measurement of constant flow velocity in a small tube at spatial peak velocities for one pixel.
PURPOSE: We examined the spatial factors influencing magnetic resonance (MR) flow velocity measurements in a small tube phantom and used the same measurements obtained with an intraluminal Doppler guidewire as reference. MATERIALS AND METHODS: We generated constant flow velocities from approximately 40 to 370 cm/s in a tube 4 mm in diameter. We then performed segmented k-space, phase-contrast cine-MR imaging to quantify spatial peak flow velocities of one pixel and of five adjacent pixels as well as spatial mean velocities within regions of interest in a cross section of the phantom. Pixel dimensions ranged from 1.00 x 1.00 mm to 2.50 x 2.50 mm. We compared the MR measurements with the temporally averaged Doppler spectral peak velocities. RESULTS: For one pixel (r > 0.99: MR flow velocity for pixel dimension 1.00 x 1.00 mm = 1.03x + 9.8 cm/s), the linear correlation was excellent between flow velocities by MR and Doppler guidewire methods. However, for the five adjacent pixels, MR measurements were significantly underestimated using pixels 1.25 x 1.25 mm to 2.50 x 2.50 mm and for mean velocities for all pixel dimensions. CONCLUSION: Relatively high spatial resolution allows accurate MR measurement of constant flow velocity in a small tube at spatial peak velocities for one pixel.
Authors: George P Chatzimavroudis; Haosen Zhang; Sandra S Halliburton; James R Moore; Orlando P Simonetti; Paulo R Schvartzman; Arthur E Stillman; Richard D White Journal: J Magn Reson Imaging Date: 2003-01 Impact factor: 4.813
Authors: Hermann Körperich; Jürgen Gieseke; Peter Barth; Romhild Hoogeveen; Hermann Esdorn; Andreas Peterschröder; Hans Meyer; Philipp Beerbaum Journal: Circulation Date: 2004-04-05 Impact factor: 29.690
Authors: R Zivadinov; R Galeotti; D Hojnacki; E Menegatti; M G Dwyer; C Schirda; A M Malagoni; K Marr; C Kennedy; I Bartolomei; C Magnano; F Salvi; B Weinstock-Guttman; P Zamboni Journal: AJNR Am J Neuroradiol Date: 2011-04-07 Impact factor: 3.825