ARTIFACT SIMULATING SUBARACHNOID AND INTRAVENTRICULAR HEMORRHAGE ON SINGLE SHOT FAST SPIN ECHO FLAIR IMAGES: A TRAP FOR THE UNWARY
Bydder G, Martin M, Cianfoni A, Hesselink J, Du J, Bradley W, Imbesi S
University of California, San Diego
Single-shot-fast-spin-echo fluid attenuated inversion recovery (SS-FSE-FLAIR) images frequently show high signal artifacts in regions not associated with high CSF flow when confused patients are examined. Experiments on volunteers showed that these were due to head motion between the initial inversion pulse and the subsequent 900 pulse. Similar patterns were seen in patients. The artifacts represent a trap since single-shot sequences are frequently used in uncooperative patients who are at risk of intracranial hemorrhage and they simulate this condition on otherwise non-artifacted images. They could be controlled by increasing the width of the initial inversion pulse or using a non-selective pulse.