Dependence of venous enhancement on the field of view in 3D contrast-enhanced MRA using the elliptical centric view order

The dependence of venous suppression on the acquisition field of view (FOV) in elliptical centric 3D contrast-enhanced magnetic resonance angiography (CE-MRA) is studied theoretically and experimentally. It is hypothesized th at a reduced FOV in an arterial phase acquisition results in improved venou s suppression. An expression is derived linking the k-space representation of a vein to venous return time and acquisition parameters. For a y x z FOV reduction from 24 cm x 7.2 cm to 18 cm x 3.6 cm, equivalent voxel size, an d venous return times ranging from 0-7 s, the mean improvement in venous su ppression ranged from 7.0% for the 19-mm-diameter vein to 32,1% in the 6-mm -diameter vein, assuming a step function-shaped venous enhancement profile. Decreased venous enhancement with reduced FOV is also observed for scans w ith equivalent acquisition times, although the degree of suppression is dep endent on the shape of the venous enhancement curve. (C) 2001 Wiley-Liss, I nc.