Magnetic resonance flow-space angiography means that the flow-space effect of magnetic resonance is used to visualize blood vessels. The essence of magnetic resonance angiography is that it causes the hydrogen atoms in the tissues of the body to appear as a signal, and when the hydrogen atoms are in the blood, as the blood flows, those hydrogen atoms that appear as a signal will flow to other parts of the body, causing the signal to disappear, so that the image of the blood vessels appears as a low signal black on both the T1 image and the T2 image. This condition can be used to identify the presence and degree of stenosis, and the advantage of performing angiography in this way is that it is noninvasive and does not require the use of contrast agents, so the flow-space effect of magnetic resonance can be used to visualize blood vessels.