Star artifact

The Star artifact is a peripheral signal artifact that appears as a bright spot close to the middle of the image. This artifact is caused from signals generated outside the desired FOV that are detected by the receiver. Star artifact signals originate very far from isocenter. In that non-linear region, the FID signal coming off the RF 180 pulse or from a SAT pulse is not crushed out and aliases back into the image.

The FSE sagittal thoracic spine image below presents a Star artifact. The image was acquired with spine48, 28 cm FOV, and the phase and frequency swapped. The artifact could have been prevented by not swapping phase and frequency and using a 2-tile selection, such as spine32 so the surface coil coverage would closer match the scan FOV.