Efficient kidney perfusion imaging using non-segmented coronal slab 3D echo planar imaging with pseudo continuous arterial spin labeling

Arterial spin labeling (ASL) of the kidneys provides several advantages for the evaluation of kidney perfusion including contrast agent free studies while allowing multiple scans over a short time period. 3D acquisition provides higher SNR and with centric k-space encoding provides a well-defined post-labeling delay which makes background suppression pulses more effective. Prior techniques for 3D ASL perfusion imaging employed segmented GRASE with multi-TI FAIR and segmented TSE with pCASL. These acquisition schemes can be limited in resolution or require coached breathing along with providing limited coverage over an extended scanning time. In this work, we used non-segmented 3D EPI pCASL with coronal acquisition to efficiently image the two kidneys in a shorter time (nominal time 2:15) with increased control-label pairs. Background suppression and saturation pulses were also employed to reduce tissue related noise and signal from aorta, respectively. Cortical and medullary perfusion values were calculated in seven subjects which matched well with values from literature. In addition, good correspondence with transverse slab acquisition as well as good repeatability was shown.