For imaging the upper abdomen or chest, cardiac gating with respiratory triggering or navigator echoes is commonly employed to reduce motion artifacts. An optional chemical shift selective fat suppression pulse (e.g. SPIR) is also frequently applied immediately before readout. Alternatively, water excitation or a Dixon method may be used.
In some cases additional obliquely oriented saturation bands may be placed over the kidneys as well. To further suppress signal from the inferior vena cava, a third inversion band is sometimes applied inferior to the larger first (blue) band at an intermediate TI value (e.g., 400-800 msec). Many variations are possible.
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Inflow-enhanced balanced SSFP MRA techniques are sometimes classified as a type of arterial spin labeling (ASL) method. I do not like this classification because the fresh blood flowing into the saturated slab has not been specifically labelled by an RF-pulse as would occur in a true ASL sequence. The inflowing blood gives off a high signal because it remains fully magnetized (unlike the saturated blood and background tissue within the imaging volume). So to me this is more of an IR-based saturation technique more similar to TOF MRA than a spin-labeling technique.
Katoh M, Buecker A, Stuber M, et al. Free-breathing renal MR angiography with steady-state free-precession (SSFP) and slab-selective spin inversion: initial results. Kidney Internat 2004; 66:1272-1278.
Rick M, Kaarmann N, Weale P, Schmitt P. How I do it: Non contrast-enhanced MR angiography (syngo NATIVE). MAGNETOM Flash 2009; 3:18-23.