title: Motion of the distal renal artery during three-dimensional contrast-enhanced breath-hold MRA.
abstract: 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.
authors.affiliation: Department of Radiology, Maastricht University Hospital, Maastricht, The Netherlands. vasbinder@rad.unimaas.nl
authors.forename: G Boudewijn C
authors.initials: GB
authors.lastname: Vasbinder
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Maki
authors.forename: Robbert J
authors.initials: RJ
authors.lastname: Nijenhuis
authors.forename: Tim
authors.initials: T
authors.lastname: Leiner
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Wilson
authors.forename: Alfons G H
authors.initials: AG
authors.lastname: Kessels
authors.forename: Etienne E L E
authors.initials: EE
authors.lastname: Lemaire
authors.forename: Dave W
authors.initials: DW
authors.lastname: Kaandorp
authors.forename: Kai Yiu J A M
authors.initials: KY
authors.lastname: Ho
authors.forename: Jos M A
authors.initials: JM
authors.lastname: van Engelshoven
authors.forename: Etienne E L E
authors.initials: EE
authors.lastname: Lemarie
mesh_terms: 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