The Technology of Magnetic Resonance Angiograph
Wang Jinhuai, et al
Magnetic Resonance Angiography (MRA) is introduced, which is a kind of technology of MRI applied in blood flow. MRA shows only the blood flow and suppresses the static tissue. Various aspects about this technology such as potential clinical application, background, methods and pluse sequences are presented, The techniqes of MRA have been developed today and fallen into two classes. The first class is the time-of-flight methods which tag a bolus of material in one region and detect in another region. The second class is the phase contrast methods which rely on motion-induced phase shifts in transverse spin magnetization. The present difficulties in MRA are presented and discussed.