Renal artery blood flow: quantitation with phase-contrast MR imaging with and without breath holding.
OBJECTIVE
To compare the accuracy of 16-frame cine phase-contrast (PC) magnetic resonance (MR) imaging with those of two breath-hold PC techniques in the measurement of renal artery blood flow.


METHODS
In vitro flow measurements were performed in a segment of harvested human artery embedded in gel. For the cine PC acquisition, respiratory motion was simulated. In eight subjects with recently obtained para-amino-hippurate-clearance renal blood flow data, renal artery flow measurements were subsequently performed with two breath-hold imaging techniques and with cine PC imaging during shallow respiration.


RESULTS
Breath-hold sequences were significantly more accurate than conventional cine PC sequences both in vitro (P < .005) and in vivo (P < .05). Cine PC imaging tended to overestimate flow (in vivo mean, 24.47% +/- 9.94), reflecting artifactual enlargement of the apparent vessel size.


CONCLUSIONS
Reliable blood flow measurements in the renal artery are possible with breath-hold PC MR imaging.
Debatin
J F
JF
Department of Radiology, Stanford University School of Medicine, Calif.
Ting
R H
RH
Wegmüller
H
H
Sommer
F G
FG
Fredrickson
J O
JO
Brosnan
T J
TJ
Bowman
B S
BS
Myers
B D
BD
Herfkens
R J
RJ
Pelc
N J
NJ
D000328:Adult; D001783:Blood Flow Velocity; D006801:Humans; D066298:In Vitro Techniques; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D008961:Models, Structural; D012077:Renal Artery / Q000033:anatomy & histology / Q000502:physiology*; D012082:Renal Veins / Q000033:anatomy & histology / Q000502:physiology; D012119:Respiration