title: Dynamic MR venography: an intrinsic benefit of time-resolved MR angiography.
abstract: OBJECTIVE
  To investigate the possibility of obtaining dynamic contrast-enhanced magnetic resonance venography (DCE-MRV) images of the lower extremities.
  
  
  METHODS
  Peripheral contrast-enhanced magnetic resonance angiography (CE-MRA) was performed on 20 patients using a time-resolved sequence that combined undersampled projection reconstruction (PR) in-plane and Cartesian slice encoding through-plane. The contrast dynamics of distal vessels were depicted. An automated segmentation algorithm based on a contrast arrival time (CAT) threshold was used to generate contrast dynamics in the venous system. The signal difference between the vein and artery was measured to evaluate the effectiveness of this technique in isolating the venous contrast dynamics.
  
  
  RESULTS
  The automatically generated image series depicted the contrast dynamics of both the arterial and venous systems, including asymmetric venous enhancement and background tissue enhancement. Quantitative measurement showed a mean venous/arterial signal ratio increase from 1.58 to 4.82 for the peak venous frame after arterial signal suppression.
  
  
  CONCLUSIONS
  DCE-MRV is a minimally invasive technique for evaluating the venous side of the systemic vascular anatomy. Time-resolved MRA has the potential clinical benefit of enabling both arterial and venous disease to be detected in patients undergoing CE-MRA.
authors.affiliation: Department of Medical Physics, University of Wisconsin-Madison, Wisconsin, USA. jiangdu@ucsd.edu
authors.forename: Jiang
authors.initials: J
authors.lastname: Du
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Thornton
authors.forename: Charles A
authors.initials: CA
authors.lastname: Mistretta
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Grist
mesh_terms: D003287:Contrast Media; D005240:Feasibility Studies; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000175:diagnosis*
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA