Subject-Specific Circular Artifacts in ASL Perfusion Imaging with 3D Stack-of-Spirals FSE Readout

In perfusion images of ASL scans of brain, artifacts originated from unlabeled blood inflow can be effectively suppressed by inferior saturation. In our study with spiral-based readout, artifacts in the patterns of bright spots and concentric rings were determined to arise from arterial blood inflow. We discovered that the emergence of the artifacts is directly related to the carotid artery anatomies of human subjects. The artifacts appeared persistently for just one out of four participating volunteers. The application of inferior saturation should be favored to avoid such artifacts, which had been a fact not fully recognized from recent ASL studies.