Phase contrast, line-scanned method for NMR angiography.

摘要

An NMR angiogram is produced using a line scan data acquisition. Each line of NMR data is acquired twice, once with a velocity sensitizing gradient having a positive first moment and once with a velocity sensitizing gradient having a negative first moment. The two signals from the acquisition are subtracted to cancel signals from stationary spins while enhancing signals from flowing spins. The magnitude of the velocity sensitizing gradient moment is changed during the cardiac cycle so that aliasing does not occur at high blood velocities and the signal strength does not drop too low at low blood velocities. An angiogram is produced by reconstructing an image from line scan data acquired from a series of slices.