CONTINUOUS INVERSION ANGIOGRAPHY

A subtractive time-of-flight technique for magnetic resonance angiogra phy is described. In this approach, the arterial supply to an organ is inverted in a steady-state fashion by applying off-resonance irradiat ion in the presence of a linear magnetic field gradient. An angiogram is formed by subtracting an image acquired with arterial inversion fro m a control image acquired with no arterial inversion. A single coll i s used to apply both the inversion and observation pulses. Intracrania l angiograms obtained from normal volunteers using a two-dimensional p rojective implementation of this technique at 1.5 T illustrate excelle nt small vessel detail and background suppression.