Motion of the distal renal artery during three-dimensional contrast-enhanced breath-hold MRA.
OBJECTIVE
To study the potential detrimental effects of renal motion on breath-hold three-dimensional contrast-enhanced (CE) magnetic resonance angiography (MRA).


METHODS
A computer model simulating linear motion was applied to MRA pulse sequences. Subsequently, to study whether renal motion was present, 24 patients being evaluated for possible renovascular hypertension underwent a breath-hold nonenhanced single slice two-dimensional dynamic turbo field-echo magnetic resonance imaging (MRI) scan with a typical duration of 32 seconds. This sequence was followed by breath-hold three-dimensional CE renal MRA. CE-MRA images were evaluated by two independent observers.


RESULTS
The computer model revealed linear renal motion to cause artifacts. The severity of these artifacts correlated with velocity. Significant (P < 0.001) near linear cranial motion of the kidneys and diaphragm during a sustained breath-hold was found for the right kidney, left kidney, right diaphragm, and left diaphragm (0.26 +/- 0.21 mm/second, 0.25 +/- 0.23 mm/second, 0.43 +/- 0.43 mm/second, and 0.29 +/- 0.33 mm/second [mean +/- SD], respectively). CE-MRA images showed artifacts of the distal renal artery that corroborated the computer model findings.


CONCLUSIONS
The observed cranial motion of the kidneys during a breath-hold adversely affects distal renal artery image quality on three-dimensional CE-MRA and jeopardizes reliable clinical evaluation. Shortening scan time may be beneficial for decreasing image degradation caused by this phenomenon.
Vasbinder
G Boudewijn C
GB
Department of Radiology, Maastricht University Hospital, Maastricht, The Netherlands. vasbinder@rad.unimaas.nl
Maki
Jeffrey H
JH
Nijenhuis
Robbert J
RJ
Leiner
Tim
T
Wilson
Gregory J
GJ
Kessels
Alfons G H
AG
Lemaire
Etienne E L E
EE
Kaandorp
Dave W
DW
Ho
Kai Yiu J A M
KY
van Engelshoven
Jos M A
JM
Lemarie
Etienne E L E
EE
D000328:Adult; D000368:Aged; D016477:Artifacts; D003198:Computer Simulation; D005260:Female; D006801:Humans; D006978:Hypertension, Renovascular / Q000175:diagnosis; D021621:Imaging, Three-Dimensional; D016014:Linear Models; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009068:Movement; D012077:Renal Artery / Q000502:physiology*; D018709:Statistics, Nonparametric